# Question
Title: Does CBT help with non-sexual crime recidivism rates?
In the same vain as a previous question I asked, (Are Sex Offender Treatment Programmes (SOTPs) effective?) I am wondering if CBT (Cognitive Behavioural Therapy) based therapies and interventions have helped with recidivism rates of non-sexual crimes.

Considering SOTPs are CBT based, and the fact that, as pointed out in my answer to Cognitive-Behavioral Therapy Limitations,

> The Countess of Mar in the House of Lords suggested the results of a trial into the effectiveness of CBT and GET (graded exercise therapy) had been artificially inflated

I do not hold much hope.

An answer to the question What do experts consider best mental techniques to avoid succumbing to temptations? has an *n*=1 case study where a kleptomaniac was supposedly treated with CBT (Schwartz & Hoellen, 1991).

But, is it possible that client went on and started again just like many sex offenders who have gone through SOTPs?

## References

Schwartz, D., & Hoellen, B. (1991). "Forbidden Fruit Tastes Especially Sweet." Cognitive-Behavior Therapy with a Kleptomaniac Woman-A Case Report. *Psychotherapy in private practice, 8*(4), 19-25. https://www.tandfonline.com/doi/abs/10.1300/J294v08n04\_03

# Answer
A psychoanalytic approach seems to suit treatment of sex offenders, more so than CBT. Generally speaking, the past is prioritized more is psychoanalysis. Research shows that sex offenders commonly have their own unresolved trauma.

However, I'm thinking that the treatment of kleptomania may warrant an eclectic approach in theoretical orientation (to therapy). More specifically, one that incorporates CBT to help make more practical decisions in the moment, and to control thoughts that lead to making an irrational decision to steal. At the same time, a psychoanalytic approach can be used to address more complex issues that lead to these behaviors in the fist place.

Please add relevant research to the chain on treatment of kleptomania, regarding what theoretical orientations have been used, and research on the benefits/ and disadvantages of approaches.

One important piece that will vary by individual, is whether kleptomania is the only symptom of mania in the patient, or if kleptomania is only one feature of mania that materializes. In the former, kleptomania may be a symptom of a larger issue, such as bipolar disorder. Related, or a feature of a crisis, related to bipolar disorder.

**References**

Costopoulos, J. S., & Juni, S. (2018). Psychoanalytic understanding of the origins of sexual violence. Journal of Forensic Psychology Research and Practice, 18(1), 57-76.
> 1 votes

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Tags: abnormal-psychology, clinical-psychology, criminology
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# Question
Title: "Polysemous heuristics": people trusts Tesla Inc more if they already trusted Nikola Tesla, even though those two are unrelated
For example, because of massive number of films and online short videos, the population is convinced that Tesla is a great inventor. The population is more likely to give a positive opinion (or positive familiarity) and more attention on Tesla Inc, even though the greatness of an 19th inventor is unrelated with the trustworthiness of Tesla Inc.

Example 2: ZOOM technology, a company irrelevant with the online video conferencing technology, surged from 1.05 USD to 10.40 USD per share during the outbreak of Covid in early 2020. At the same time, Corona popularity also vastly increased.

**What is the academic terminology or related papers on this heuristic?**

Examples of similar effects include "stereotype heuristic".

# Answer
> 1 votes
Associating Zoom Technologies with Zoom Video Communications is just a case of misattribution through lack of knowledge. https://markets.businessinsider.com/news/stocks/publicly-listed-zoom-video-communications-traders-buying-zoom-technologies-2019-4

Popularity of Corona (the pale lager) could be associated with the covid-19 outbreak but only through the coincidental pun association.

I cannot see how Tesla Inc. can be associated with the 19th/20th century engineer, Nikola Tesla, when he died long before the company was formed. I think that it is a tall order to associate the 2 together.

This is a prime example of **correlation vs causation**. Correlates do not necessarily mean causes. Or, as Wikipedia puts it

> Correlation does not imply causation

You said in comments that

> I understand that N. Tesla died a long time ago. However, recently after 2010, there are vast number of movies and short films about N. Tesla, and thus the popularity of N. Tesla increased (as identified by google metrics). Then comes the raise of Tesla Inc.

I don't know what metrics Google used, but please think about this.

Just because more people are aware of Nikola Tesla and his contributions toward electrical technology, it does not mean the increase in the stock market share price of Tesla Inc. was not due to the fact that there is a drive to get people to buy electric cars rather than fossil fueled cars for their environmental benefits.

Maybe it was another case of misattribution. After all, Ford was named after Henry Ford, the inventor of the Model T Ford, one of the first mass production vehicles, allowing Ford to achieve his aim of manufacturing the universal car. Bell Telecommunications was named after the inventor of the telephone,

> Alexander Graham Bell, who also co-founded Bell Telephone Company in Boston, Massachusetts.

The list can go on.

Maybe there is a large group of investors who see the benefit of the work Tesla are doing and wish to invest in order to help Tesla Inc. to produce more efficient electric cars.

Maybe there is a large group of environmentalists who want to do the same.

It may be down to the "Halo Effect", put across in the answer by @ArnonWeinberg to What is the name of the bias that associate a thing as good because it has a relation to another good thing?

There is a lot of opinion and supposition within your question which needs to be addressed before these correlations can truly be attributed to the cause of these rises in figures.

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Tags: cognitive-psychology, terminology, experimental-psychology, bias, heuristics
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# Question
Title: What is the most ideal way to study the effect of a drug on a person over time?
What is the theoretically most optimal way of determining the longterm effects of a drug? Is it large scale population studies in which questionnaires determine frequency of use of a drug and comprehensive, detailed measurements attempt to rate a level on a wide variety of health characteristics?

# Answer
I don't think it's possible to say any approach is "most ideal"; every approach has drawbacks and benefits, but these are not measurable on the same scale. Comparing the alternatives is about making judgments between those distinct pros/cons.

Free of time, money, and possible ethical constraints, a prospective randomized controlled trial is the best option. I suppose for "theoretically", this is probably the answer you'd find in a textbook, though that isn't specific to long-term effects but rather just about anything. Barriers are the cost of following individuals over time, loss of subjects to follow-up as they change addresses/phone numbers or move in and out of care facilities, ethical concerns assuming the drug you're giving is intended to treat some condition (hence you're maintaining a control group that loses access to any benefits), failure to adhere to the study design (people in the test group stop taking the drug; people in a control group are prescribed the drug or a different one to treat the same condition), and more. There is also sometimes a lack of validity in controlled trials, in that the conditions of a trial do not replicate well in the real-world, where dosing actually does vary: people miss doses or double up, temporarily wean on-and-off drugs as their finances or healthcare personnel change, or people are prescribed drugs despite not fitting into the originally intended population (off-label use, pediatric use, use in pregnancy).

Retrospective designs or natural experiments (such as before and after a drug is introduced to a population, or in different geographic locations that have or don't have access to a drug) can cover a lot of the cost and practical problems with randomized trials, but come with biases that make it harder to attribute causality. There is a lot of selection bias in who gets prescribed a drug. It can also be dangerous to make inferences from certain statistics, like causes of death. One might expect rates of cancer to increase in a population that is newly introduced to a heart medication simply because everyone eventually dies of something, and every person who lives 10 years longer because they didn't die of heart disease has more time to develop cancer.

Mechanistic studies or surrogate endpoints may let you make strong educated guesses about long-term effects without having to wait. For example, changes in liver enzymes may indicate liver toxicity: you need not wait until actual liver disease develops. Same for effects on blood pressure or heart rate.
> 1 votes

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Tags: drugs
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# Question
Title: Are there studies on politeness towards machines?
I noticed in several places (usually on web forms, but also with virtual assistants) that there is sometimes (or usually) an expectation of being polite towards the computer or device.

An example would be a button "yes, please" or "no, thank you" instead of a "yes" or "no".

I also read about a casual review of how people interact with Alexa or Google Assistant - a sizable part (I think it was 30%) would say "yes please".

**I was wondering whether there was interesting research in that area, which could give some substance to hand-waving theories.**

Notes:

* I work in IT for the past 30 years so I am used to talking to my computer (asking him to please go faster, or telling because my code does not work. I do not have "casual exchanges", though.
* for the less serious aspect of that question, see https://www.youtube.com/watch?v=NMS2VnDveP8 (2:25 for the politeness part, but the whole video is worth watching)

# Answer
> 4 votes
There seems to be a bit of information on this topic, with this type of research starting in the 1990s, according to Nielsen, Pfattheicher, and Keijsers (2021), who believe that humans tend to have often mindless, or automatic, prosocial attitudes and behaviors towards machines and that their use in research can help open new doors into human cognition as machines give some flexibility within some elements in research design (confederates, moral issues, etc).

On the other end of the spectrum, Brščić, D., Kidokoro, H., Suehiro, Y., & Kanda, T. (2015), found that children were often mean or abusive to robots, with the children being more aggressive towards the machines given two factors: how many other children were present and how much time was spent with the robot.

It seems that kids might be the exception to the rule when it comes to prosocial interactions with machines, of course it should be noted that sample size is an issue with this line of research, at least at the moment as pointed out by Nielsen et al.,(2021).

These articles might help in getting you started on human machine interactions, though it appears to be in preliminary stages.

References:

Brščić, D., Kidokoro, H., Suehiro, Y., & Kanda, T. (2015, March). Escaping from children's abuse of social robots. In Proceedings of the tenth annual acm/ieee international conference on human-robot interaction (pp. 59-66). https://doi.org/10.1145/2696454.2696468

Nielsen, Y. A., Pfattheicher, S., & Keijsers, M. (2021). Prosocial behavior towards machines. Current Opinion in Psychology. doi: 10.1016/j.copsyc.2021.08.004

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Tags: cross-cultural-psychology
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# Question
Title: What is the inverse of anthropomorphism?
Anthropomorphism is the attribution of human traits, emotions, or intentions to non-human entities. However, one often can observe the inverse happening as well. Namely the attribution of non-human entities’ traits, emotions, or intentions to human entities. For example the biography book about Winston Churchill is called “The Last Lion” or professional boxers being nicknamed “Pitbull”, “Tiger”,”The Hammer”, etc.

Or would this be just an extension of anthropomorphism in which humans attribute human traits, emotions, or intentions onto non-human entities and then relate them back to humans again? Because, in order to attribute non-human entities’ traits, emotions, or intentions onto humans, one would first need to attribute human traits, emotions, or intentions onto non-human entities?

# Answer
Wikipedia explains zoomorphism,

> Contrary to anthropomorphism, which views animal or non-animal behavior in human terms, zoomorphism is the tendency of viewing human behavior in terms of the behavior of animals.
> 3 votes

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Tags: psychology
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# Question
Title: How can the action of drugs be determined by so few neurotransmitters?
It seems that there is a huge variety of mind-altering drugs with unique mental characteristics in terms of qualitative experience, yet the action of drugs is frequently explained as being the result of influencing the amount of key neurotransmitters in the brain, often dopamine, serotonin and neuroepinephrine.

Is this an overly reductionistic view of how drugs change brain activity? Why should the effect of drugs so often be explained just in terms of these common neurotransmitters?

# Answer
The brief answer to your question is that:

* Serotonin to be clear is not a primary neurotransmitter, as it is not a primary driver or inhibitor of action potential generation --- the core signal by which we understand our brain encodes information --- but rather a neuromodulator that tends to indeed 'modulate' the effect of glutamate and GABA among other classical neurotransmitters.
* So, serotonin is likely best thought of as a mechanism akin to the effect of weather or social pressure on human conversations.
* Thus, as serotonin levels change, they affect the tone, the tempo, and the general intensity of the signaling without distorting the signals at their core level - this is part of the reason why they work without causing substantial dysfunction which is what can happen if you cause significant changes in the effect of primary neurotransmitters (e.g., Ketamine for glutamate, EtOh for GABA).

The somewhat longer answer to your question has to do with coding. In computer chips, you just have one encoding signal, that is electrons. The 1s or 0s of digital circuitry are stored simply on whether the number of electrons at a certain physical location is below or above a certain intensity threshold. Reframing your question, one could ask, how is it that computer chips can do so much with just one 'encoding signal?' Is such a viewpoint overly reductionist? We know it is not overly reductionistic because we know that is actually how computers work. Rather, digital 1s and 0s vary in significance and effect depending on where they are stored.

As it relates to neural signals, the same neurotransmitter means 'different things' not just depending on where it is released in relation to a particular neuron, but also depending on the following:

1. timing
2. duration
3. intensity
4. dendritic location (closest equivalent to the "where")
5. neuronal map location
6. coincidence of signals
7. presynaptic neuromodulation
8. postsynaptic neuromodulation
9. intracellular 2nd messenger
10. transcriptional activity
11. post-transcriptional effects
12. methylation effects
13. cross-brain synchrony
14. interactions with supporting cells (e.g., astrocytes)
15. mirror neurons incl. language-speaking more broadly
16. transaxonal transport mechanisms
17. retrograde signaling
> 3 votes

# Answer
Put simply, this is because many "mind-altering drugs" work by changing levels of neurotransmitters at the synapse. The most common example perhaps is the use of SSRIs (Selective Serotonin Reuptake Inhibitors) for depression, like Paxil or Prozac. These drugs increase the amount of serotonin by blocking the reabsorption of the neurotransmitter at the pre-synapse. Thus, increasing the amount of serotonin for the post-synaptic neuron, and increasing the amount of serotonin absorbed there.

LSD (the psychedelic drug) also binds to receptors of neurons to influence the way serotonin is absorbed (more specifically acts as a receptor agonist). This is what induces the psychedelic effect, such as changes in auditory and visual processing.
> 0 votes

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Tags: neuro-transmitters
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# Question
Title: Isn't fluid intelligence necessarily influenced by crystallized intelligence?
In this article, it is said:

> Conversely, Gf \[general fluid intelligence\] represents the ability to employ a type of mental operation to independently reason and solve novel problems; it does not benefit from acquired experience.

I can't see how any mental operation wouldn't be influenced by acquired experience, no matter the novelty of the problem it is being applied to. Humans draw analogies; see patterns. My problem-solving skills are just becoming better and better the more I learn, and I find myself using pieces of knowledge to help solve problems seemingly disparate from those pieces of knowledge.

So, during any assessment of Gf, how can one know that there isn't any Gc involved in the problem-solving? What kind of problems only have solutions that evade the influence of Gc?

**EDIT:** Someone in the comments said that they couldn't find the quote, so here are some directions:

It's in the second paragraph within the *Introduction* section.

# Answer
> 2 votes
I think you are thinking about the concepts a bit differently than they are intended to be thought about. It isn't like Gc and Gf are completely separate software programs that solve problems, it's that they are two possible dimensions which can explain performance on certain tasks. Together, they make up the overall "g" factor which represents correlation in performance on tasks that are otherwise different. Some people seem to be simply better or worse at tasks than others, rather than better or worse at each specific task.

It seems that part of this difference can be explained by different levels of acquired knowledge and experience. However, part of it still can't be explained by that, and that remaining part is the fluid part.

> I can't see how any mental operation wouldn't be influenced by acquired experience

There isn't any claim that this is the case for fluid intelligence. Rather, it seems there is variation in how people perform mental operations *even if they have the same acquired experience*; the Cattell theory calls this difference "fluid intelligence". Yes, it's difficult to measure, and that's partly why so many different tests have been proposed to try to measure it; Wikipedia has a partial list at https://en.wikipedia.org/wiki/Fluid\_and\_crystallized\_intelligence Most (all?) of these tests use peculiar puzzles that are highly unlikely to be encountered outside of these tests to minimize contributions of crystallized intelligence solutions.

I think it's better to think about all of these concepts as "differences from average" or differences from some hypothetical matched case. There is no concept of having "only fluid intelligence" or using only fluid intelligence in the theory. You might see something similar in evaluating athletic ability, where you could have separate dimensions for speed and agility. It doesn't make sense to think of anyone as having zero speed or agility, yet it is clear that some athletes are better than the average because of their speed yet have average agility, and other athletes have better than the average agility yet have average speed.

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Tags: measurement, terminology, intelligence, problem-solving
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# Question
Title: What is the relationship between identity and personality?
I would like to know whether identity and personality are the same thing, as they both answer the question of who you are. Nevertheless in a cognitive approach, identity is considered a part of personality, concretely it's considered as a brain structure inside of the memory.

# Answer
> 1 votes
I think the relation is more or less subjective.

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***Identity*** is something that you give yourself. It has to do with what you stand for, morals, values, etc.

It is who your are physically and legally, but that's just a basic "*you already know that*" statement.

***Personality*** is the way in which you portray or "live in" your identity.

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For example, you can identify parts of someone's personality: *humorous, attractive, intelligent, funny.*

Both adapt and change over time, but your identity changes less often, I believe. Together, they are what makes **a whole person.**

It's really difficult to give a concrete answer because a lot of this can be subjective, debatable and complex.

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It's also important to remember that while in some cases your personality and identity may be the same, in the end, they serve different "roles." If someone says "you're unique", it's true. Both your ***identity*** and ***personality*** are what makes you unique. They help each other in that way.

**Let's take a look at this from a different angle:** Let's say that we know this guy named Tom is a murderer. That is his identity. His personality, however, may **not** portray that and can come off as fun or charming. Personality is how someone behaves. They both go really well together but that doesn't mean that they are always similar. In most cases, you will find that they are similar, though.

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**Sources**

1. Personality vs. Identity | Authentic Systems - Motivation Research & Development
2. Discover Your Personality | Truity
3. The Difference Between Personality & Identity | HiNative

# Answer
> 1 votes
Identity as defined by the American Psychological Association (APA). Some key characteristics include:

1. self-defined (i.e. an individuals sense of self)
2. sense of continuity over time
3. physical, psychological, and interpersonal characteristics, including values, beliefs and expectations pertaining to the self

Personality as defined by the APA. Some key characteristics include:

1. emerges from individual’s unique adjustment to life (dynamic integration of nature and nurture, such as hereditary and social influence)
2. includes major traits, interests, drives, values, self-concept, abilities, and emotional patterns
3. continuity over time

One key distinction, based on the APA definition of concepts, is that identity is self-defined. Emotional patterns and traits are exclusively personality domains, whereas interpersonal roles (i.e. mother, brother, group member) are exclusively identity domains.

At the same time, there is some grey area between the two domains. Such as values. For example, Latin Americans (compared to those in the US) may be more likely to have collectivistic (as opposed to individualistic) value systems (relating to identity), centering around prioritizing the needs of the group over that of your own, likewise, have extroverted personality types.

# Answer
> -1 votes
In my opinion, I think identity is a kind of inheritance. Something that the world gives you that you can't change. For example, you can't change your date of birth or where you were born. My birthday is part of my identity. I'm Iranian and being Iranian is a part of my identity. My parents gave me a name so it's another part of my identity. Although, personality is something that makes me unique. For example, there are many people who were born on the same date and even live in the same place. Many people have the same name as me, but not my rules, demands, priorities, experiences, education, and so on. None of them think and act like me. Personalty is all of those covers and masks I use on myself in the world. This is my personalty. Maybe all I said was false, but I just wanted to share my opinion.

# Answer
> -2 votes
Personality is both something we're born with - inate personality traits - and something we develop based on our environment, hopes and dreams.

Identity is something we grow into as a result of society reflecting back on us who the wish us to be, who they demand us to be, and the individual circumstances of our existence - where we fit into different status roles.

Our personality can imact our identity and how adapative we are to life's turn of events. We can be stubborn (a personality trait) and that makes it hard to change when needed, such as an identity loss occurs (from married to single) and we need to figure out who we are now, with that irretrivable loss.

On the other hand, our identity can be so fragile that we often adapt our personality to fit the needs of others over our own needs. The people pleaser identity.

Both words are comopeltey intertwined and it's a chicken or the egg phenomonon. And to me - identity is the gestalt, defined by the roles we play and our beliefs about our status.

While personality is more about behaviour - actions that others can actually see.

In the end, identity is the answer to the question "Who are you?"

Personality is the answer to the question "What type of person are you?"

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Tags: cognitive-neuroscience, personality
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# Question
Title: How do I counter the argument that since each person is different, there can't ever be a general scientific theory to blanket the minds?
I am interested in psychology and psychiatry but often a counter argument given by others when I bring up this topic is that since each person is different mentally, there can't be a general all encompassing theory. In response, I agree to what they say and say that it is the same case with medicine. All our physiologies are technically different in slight ways from each other, but still similar enough to be studied, but, this argument is a bit weak since the idea of the mind and processes relating to it is on a more abstract level than that of our physical body.

What would be a stronger counter argument in defense of psychology and psychiatry?

# Answer
From a neuroscientific point of view, our brains are really quite similar. Two mechanisms come into play during the brain's development: nature and nurture (the extent of each giving birth to a major debate over the years).

The "nature" part is our genome, which sets the ground rules. The genome means that our nervous tissue is always made of the same types of cells: neurons and glia. Additionally, from a developmental biology point of view, a human embryo develops the same way across individuals, and this is the case for brain development as well. This results in a similar structure of the brain: we all have the same components, arranged roughly the same way. We all have a cerebellum, a cerebrum, a thalamus, our cortex always has 6 layers, etc. This is the first source of variation: for instance, Einstein was reported to have many astrocytes (a type of glia) compared to average people. However, the variation is small enough to allow us to construct very comprehensive theories of the brain.

The "nurture" part is due to the brain's plasticity. Most of the wiring in the brain, its synapses, are formed as a result of a learning process. This is where most of the variation comes from. Fundamental mechanisms of the brain are similar between individuals: for instance, the primary visual cortex shows the same kind of retinotopy for everyone, the primary motor cortex the same kind of somatotopy, most memories are stored in neuronal assemblies which can be modeled as attractor networks (e.g. Hopfield networks) to enable retrieval, etc. However, the more you move up the cognitive ladder, the more differences start to arise. For instance, people can have vastly different personalities.

The pivotal argument, however, is that we start with almost identical "hardware", and the "software" is a result of processes which can be generalized among groups of people, leading to a great deal of commonality among people, thus allowing theories to be constructed, abstracting away some of the myriad idiosyncrasies of each person. For instance, people who go through a romantic relationship are bound to react in a way that presents common aspects.

To sum it up, the more you move up the cognitive ladder, the less general rules you can come up with, and the more complex theories get.
> 1 votes

# Answer
Over the past few decades developmental systems approaches to psychology, encompassing relational systems, embed nature and nurture, or organism and context, accommodating for a unique developmental trajectory for each individual. There are many approaches to developmentmental systems theory. Bronfenbrenner's bio-ecological model (incorporating both proximal and distal levels to that of the individual), and Sameroff's transactional model (emphasizes transactions between organism and environment) are two.

Moreover, Lerner (2018) explains that “the mutual embeddedness of organism and context” follows that a person’s “natural attributes” can influence an infinite number of developmental outcomes based on the variations of context and time. Similiarly, Schneirla’s work helped to advance this *discontinuous* framework for development (Schneirla labels as *probabilistic epigenesis*).

One way Schneirla advanced his probabilistic epigenesis view that supports discontinuity between levels of nature and nurture, is by proposing the idea of the structure-function relationship. In human development especially, our behaviors and thoughts (function) cannot be reduced to the characteristics of specific areas in the brain (structure). Rather, Schneirla explains that humans show brain *plasticity*, that is, an ability to respond differently to the same input.

**References**

Lerner, R.M. (2018). Concepts and Theories of Human Development (4th ed.). Routledge. https://doi.org/10.4324/9780203581629
> 1 votes

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Tags: psychology, psychiatry
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# Question
Title: How do "ideas" or "concepts" appear in the brain?
I'm new to neuroscience and psychology and recently learned about Hubel & Wiesel cat experiment where "some neurons fired rapidly when presented with lines at one angle, while others responded best to another angle" link.

That made me wonder, how are "ideas" or "concepts" appear in the brain? If a single neuron can represent a certain line angle, do several of these represent a concept of a shape? Or a house? That is, is a collection of neurons that fire at the same time a "concept" or "idea"?

I was trying to find resources on this question but didn't find many other theories.

# Answer
First of all, let's look at human perception. Humans have several sensory modalities: sight, hearing, touch, etc... Note that there are many more than I just enumerated, and certainly not merely the traditionally considered 5 senses: sometimes overlooked senses include for instance chronoception (i.e. sensing the passage of time) and thermoception (feeling temperature). To illustrate my point, we will look at the best studied modality: sight. Usually, external stimuli will reach specialized neurons which act as transducers: rods and cones in the retina turn light into an electrical potential. This information, which has just entered the nervous system, will sometime undergo some limited local processing near the sensory organ: once again, this is the case for the retina, as the initial transducers are connected to other kinds of neurons in the retina itself (e.g. retinal ganglion cells, RGCs). Notably, the amacrine cells do some of this processing in the retina. The information then eventually makes its way to the thalamus (sort of a "relay station"), from which it reaches a primary dedicated processing area. For sight, this primary dedicated processing area is the primary visual cortex V1 in the occipital lobe.

Here is where it starts to get interesting. Certain cells, named simple cells, are tuned to a specific orientation of a line in a certain area of the retina, termed the receptive field: this is what you are referring to in your question. That responsiveness takes the form of the neuron firing more rapidly the closer the orientation of the line is to its preferred orientation. These neurons detect the simplest of features of an image, just small line fragments. However, they are connected to other neurons, which respond to slightly more complex features (e.g. squares, circles, etc.), which are in turn connected to other neurons, and so on and so forth. This paradigm of emergent complexity is very similar and perhaps even more striking in the convolutional neural networks (CNNs) in machine learning, which structure their neurons on layers, each layer representing more abstract features (e.g. lines to geometric primitives to body parts to humans). CNNs were actually initially inspired by the brain, and the same phenomenon of emergent complexity can be seen in the ventral pathway of the visual system, responsible for identifying an object you are looking at. The visual signal actually goes through multiple areas after V1 (V2, V3, etc., not in strict sequential order), which each deal with different more abstract information.

You should now have a pretty good idea of how individual neurons can encode information. Unfortunately, the brain isn't that simple, and the first degree of additional complexity we can consider is groups of neurons that represent information. To illustrate this, let's look at the intention of moving a limb and thus at the primary motor cortex M1. Just like for the visual system, each neuron is tuned to a specific direction of movement, and we can once again see that they fire more rapidly as that direction of movement is matched to their preferred one. But many neurons in M1 will fire at the same time when executing a movement: how to then tell which way the limb will move? The answer is simple, but requires us to account for a group of neurons which we call a neuron population. The movement is then represented as a weighted average of the neuron preferred directions, where the weights come from the firing rate of the neurons at the time: this average is called the population vector, as shown in this seminal paper.

All good, but we're still far from done. Although firing rate coding is quite common, the nature of the neural code is still a subject of debate, and there seem in fact to be multiple neural codes. For instance, temporal coding, where the precise timing of spikes carries information, has been shown to be present in certain brain areas.

Reaching now the final step (for this answer, because we can go infinitely further), information representation can involve cell assemblies in complex ways, for instance to store and retrieve memories. A memory can be stored by a group of interconnected neurons in the pattern and strength of the synapses between them. To recall that memory, once the neurons start firing, this cell assembly will converge to a stable pattern of activation, achieving memory recall.

### Resources and further learning

If the basic level of information representation in the brain which I first described is what interests you, I would suggest you look into a field called psychophysics and into perceptual learning.

If the medium complexity processes such as memory storage and recall, or decision making, interest you, I would suggest an excellent course (or its associated textbook) called Neuronal Dynamics.

Let me know if you'd like further resources in one of these directions.
> 2 votes

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Tags: neuroscience, brain
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# Question
Title: where is the second electrode in case of electrostimulation
With electrostimulation or functional electrostimulation, a response from the neuron is generated by electrical impulses.

But I always read, for example, that a stimulating electrode is above position xy of the neuron (e.g. above the axon), but in order for current to flow, there must be a closed circuit? i.e. if cathodic stimulation is used (e.g. with a -0.5mA pulse lasting 0.05ms), then there must be an anodic pole somewhere so that the current can flow, or am I misunderstanding something?

# Answer
Current flows from a high potential to a low potential, so if you inject a great deal of current via an electrode it will still flow into the body. However, even in the case of unipolar setups for deep brain stimulation (DBS), a second electrode is used, but relatively far away from the first one. Doing it this way is quite uncommon though: most electrical stimulation uses two poles (or even more), as it limits the spread of current to unwanted areas.

Transcranial direct current stimulation (tDCS) will for instance use an electrode on one side of the scalp and one on the other side.
> 2 votes

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Tags: neuroscience, cognitive-neuroscience, theoretical-neuroscience, neurophysiology, electrophysiology
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# Question
Title: Name for the effect where people cause others to fulfill their expectations
I recall hearing a social cognition lecture a number of years ago in which the lecturer described a particular idea that centered around the role of self-fulfilling prophecies in relationships. For example, if I believe that *x* is a hostile jerk, I'll tend to treat them in a way that makes them more hostile. (A good example of a book that subscribes to this type of a view is *Feeling Good Together* by David Burns; I'm not sure if he subscribes to the exact theory that I'm trying to remember, though).

I'm pretty sure that there was a specific name for this, but I don't recall what it was.

Can someone help me identify which theory or term this is?

# Answer
> 3 votes
I believe what you might be referring to is the Pygmalion effect, an effect in social psychology where high expectations lead to improved performance in a given area: a sort of self-fulfilling prophecy.

An interesting idea, but one which has sparked a lot of criticism over the years. I won't go as far as saying it has been debunked, but you might want to have a look for yourself.

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Tags: social-psychology, terminology, social-cognition
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# Question
Title: How would human consciousness react to absence of violence stimuli?
**Introduction:**

Survival on this planet, inherently involves violence and so do human instincts for establishing social hierarchies (reference: Social dominance theory). Virtually any human being faces violence (at least) at some stage of their life.

Therefore we can state that aggression always finds its place in human psyche. While all of us possess some aggression we do express it in different manners. Some of us repress it, others let it explode uncontrollably, still others try to direct it at the source of violence against them, etc.

**Question:**

Are you acquainted with any research or scientific speculations what happens when a person is put in (the unnatural) circumstances of so low levels of violence in their life, that we could assume that violence stimuli are actually absent?

# Answer
> 2 votes
This may be difficult (close to impossible) in the social sciences to create an experiment that isolates one group so that that they are not exposed to violence for a long period of time (more than a few days). But, an important question. For example, its common for research in this area to examine the influence of community violence on externalizing behavior (aggression, etc.), as a result, participants report on exposure to violence in a natural setting. Moreover, there are no experimental manipulations that control the amount of violence participants are exposed to.

However, there is research on exposure to violent media, such as on television and video games, that applies an experimental design to compare a no/low violence exposure group to a violence exposure group. In this way, its common for this research to use an intervention to decrease the amount of media use (for a given period of time), and common to measure the immediate impact of violent media across experiment conditions, (rather than eliminate violence over a long period of time). Again, lower externalizing problems (i.e. aggression) are commonly reported as a result of reducing exposure to violent stimuli (the media).

Furthermore, Anderson's et al. (2010) meta-analysis on the effects of violent video games on aggression, prosocial behavior, and empathy provides strong evidence

> that exposure to violent video games is a causal risk factor for increased aggressive behavior, aggressive cognition, and aggressive affect and for decreased empathy and prosocial behavior

Moreover, no significant differences by culture or sex we're shown.

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Tags: aggression, stimulation
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title: Gestalt Principles of Perception

text:
# Question
Title: Gestalt Principles of Perception
I have studied that Gestalt Principles are principles/laws of human perception that describe how humans group similar elements, recognize patterns, and simplify complex images when we perceive objects. But can you give me real-life examples where this is applicable in day-to-day life not just looking at some patterns in the textbook.

# Answer
Perhaps seeing where it fails will help with understanding.

Consider Forced-Perspective Photography, where the gestalt effect causes your brain to see a false vision of what is actually there.
> 2 votes

# Answer
One area where Gestalt principles are widely applied is in graphic design: for instance, for logo design. Moving to a field that's a bit bigger, Gestalt principles are also used to guide web design processes.

If you're asking not about utilitarian, "artificial" applications of Gestalt theory, but about examples of where it comes into play during day-to-day life, Gestalt principles improve the correctness of how we interpret visual information. For instance, the principle of good continuation dictates that when you see a car partly covered by a tree so that you see two distinct fragments of it, your brain still perceives it as one car and not just two separate car fragments.
> 1 votes

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Tags: cognitive-psychology, cognitive-neuroscience, cognitive-modeling, bias, metacognition
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# Question
Title: Does the brain send signals continuously to muscles during movement?
If I make one swift movement with my arm, like just raising it, is my brain continuously sending signals throughout the whole movement? Or does it just send signals one time? The latter seems to make more sense to me. Like if I send someone a text message, I only click "send" once. But I'm just not sure how it works with the nervous system. Why would the brain need to continuously send signals?

What about if it's a move that consists of multiple movements, such as waving my hand? Like I'm sure my brain must be sending signals each time my hand moves left and right. I don't think it could be like my brain tells my hand to make 5 waves, even if that's my intention.

What about when I stop a movement? Does my brain tell the muscle to stop a movement? Or does it just stop sending the signals to move?

It seems like the signals are based on intention. For instance, if I am running and I get tired, I have the intention to slow down or eventually stop, so my brain sends my muscles signals to act accordingly. But there's been times where I went running and I had something else on my mind. If this thing on my mind becomes stronger, I start losing attention on the running and thus, slow down. But did my brain really send signals to my muscles to slow down, or did it just stop sending the signals to run?

# Answer
> 3 votes
An answer from the bottom up would be as follows. A group of muscle fibers is innervated by a single motor neuron: this is called a motor unit, as it activates together, since a unique axon carries the same signal to these muscle fibers. The actual message to contract the muscle is passed at the neuromuscular junction, the interface between the axon terminal and the sarcolemma (cell membrane of the muscle fiber). Here, the signal is passed chemically: the action potential reaching the presynaptic axon terminal causes the release of a neurotransmitter called acetylcholine (ACh) which travels across the synaptic cleft and binds to nicotinic acetylcholine receptors (nAChR), which then cause another action potential to fire postsynaptically at the motor endplate, travelling via the T-tubules to cause a synchronized release of calcium from the sarcoplasmic reticulum. The sarcoplasmic reticulum is sort of like a cobweb wrapped around the myofibrils (the muscle fibers) of a muscle cell, and that release of calcium, called a calcium spark, is what directly causes the muscle to contract.

Explaining precisely how the calcium causes the muscle to contract is more a matter of molecular biology, but the point is that this calcium spark only causes a temporary contraction. So it turns out, tracing this chain of transmission back to the presynaptic motor neuron, that action potentials need to be coming in constantly to keep the muscle contracted!

However, the signal to contract the muscle isn't initiated at the motor neuron, so let's trace it further. The signal travels through a ventral root of the spinal cord, coming down from the primary motor cortex, once the decision to move the muscle has been made (of course, I've skipped many steps here).

Your question of whether this is an on-and-off signal is quite interesting, as although we know that the continuous signal is required, this on-and-off idea could make sense at a higher level in the transmission chain.

So is there an on-and-off signal in the primary motor cortex (M1)? Georgopoulos et al. is the paper usually credited with discovering the way that M1 encodes muscle activation, and it turns out that as far as we're concerned, rate coding is used: that is to say, the more frequently a neuron in M1 fires, the more the muscle will contract (very roughly speaking).

Up until now, the answer is thus that a continuous signal is used, not an on-and-off one. Of course, the discussion could be taken even higher up the chain of transmission, and it very well could be that for instance the decision to move the muscle is an on-and-off signal, but the discussion would lengthen indefinitely then...

It seems to make sense to only send an on and an off signal as opposed to a continuous signal, as this is more economical, but the difficulty in actually implementing this should not be overlooked. Indeed, at some point, there would have to be a mechanism to convert the on-and-off signal to a continuous signal.

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Tags: neuroscience, cognitive-neuroscience, neural-network
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# Question
Title: Is there a mechanism in neurons to temporarily increase membrane resistance?
I learned that electrical signal flowing out through the membrane significantly deters the voltage to move down the axon. This seems like a "bad" thing, in that it reduces the efficiency of neurons to pass information.

First of all, is this understanding correct?

Second, are there are chemicals that improve this process, either produced internally or externally?

# Answer
Yes, current leaking out of the axon can be "bad": in saltatory conduction, enough signal needs to reach the next node of Ranvier for the action potential to be regenerated. Note, however, that as long as enough current reaches the next node of Ranvier, everything is great.

In a way, this current leak is "bad" if it's severe enough. Beyond that, however, it is actually having a high membrane resistance that is "bad". First of all, passive conduction, as it happens in dendrites, is part of the natural way of the brain to perform computations. Second, in axons, a higher membrane resistance actually *decreases* the nerve conduction velocity (CV), making your brain "work slower".

There isn't really a reason to increase the membrane resistance of axons past a certain point, and our bodies naturally do this already: cells called either oligodendrocytes (in the CNS) or Schwann cells (in the PNS) increase membrane resistance by wrapping around the axons.
> 2 votes

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Tags: neuroscience
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# Question
Title: Are memories stored as patterns of chemicals/emotions?
Lately, I (as someone with no experience or prior knowledge in the topic) have been thinking about...thinking. The part that intrigues me the most is memory. As a computer-y type person, I tend to think in logic and organized systems of bytes, but I understand this way of thinking about the brain is incorrect.

From what I can half-understand half-guess from the limited information I can find online, the brain is made up of neurons which build up memories in their interactions through synapses, which send chemicals to each other.

In order to visualize, say, a thumbtack, I would need a lot of information. I think trying to recall an image of a thumbtack would send a "trigger" to a neuron, telling it to pass it on to other neurons, building up an image from these chemicals. I think I've read these chemicals are also what causes emotions (dopamine especially being the one that comes to mind), but I could be mixing things up.

So when thinking about a thumbtack, those neurons would connect in a pattern, to ensure I get all the right signals to envision one. This makes a lot of a sense to me, and explains things like forgetting and the ability to imagine and visualize inexactly with ease, but not remember exact values or images.

Could anyone provide any insight into whether my somewhat informed guesses are correct, or to any more accurate explanations of what is currently known? Thanks!

# Answer
> 4 votes
Understanding how memories are stored and retrieved in the brain is actually a pretty popular topic in neuronal dynamics. The mathematical theory of dynamical systems comes in handy here. A population of neurons can be modeled as a complete weighted graph (all possible connections between nodes are present and have a weight). The weights of these connections (read, synapses) is what encodes the memory. To understand how retrieval works, we need to talk about attractors in the theory of dynamical systems. Attractors are states toward which a dynamical system tends toward and stabilizes in. An attractor network is a graph like ours, which invariably tends toward an attractor. A simple model of memory that is an attractor network is the Hopfield network. Once retrieval has been initiated, the population of neurons will eventually settle on a single memory.

For instance, certain studies consider the existence of such attractor networks in the hippocampus, a major part of the brain's memory system.

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Tags: neuroscience, memory
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# Question
Title: Which area in the brain has the highest number of synapses?
To clarify, which structural area of the brain is the most dense in neuron synapses or connections?

I couldn't find any reliable link on the internet.

# Answer
> 1 votes
The cerebellum is the most densely packed with neurons, but its been difficult to isolate which functional region has the most neurons, and synaptic activity, because functional mapping of the cerebellum is more difficult than that of the cerebral cortex.

First, Wagner and Schnitzner (2017) explain

> there had been some hints of a larger role for the cerebellum, but scientists had a hard time following up on those hints in part because the neurons that make up most of the cerebellum are difficult to study. Those neurons, known as granule cells, account for 80 percent of the neurons in the brain – all packed into the cerebellum – but only about 10 percent of its volume. At that density, conventional techniques for recording cell activity don’t work well, and without an effective way of studying granule cells in real time, scientists were left with an incomplete picture of what the cerebellum was really doing.

Related, Essen, Donahue, and Glasser (2018) continue to explain that analysis of cells specific to functional regions (in sub-cortical regions, and in cortex) is necessary, especially to take into consideration change over time in evolution, but measurement has been a challenge

> Our analysis of numbers of neurons has so far been restricted to large brain divisions, such as the entire cerebral cortex and the ensemble of brainstem, diencephalon and basal ganglia, but an analysis of the cellular scaling of separate functional cortical areas and the related subcortical structures is underway. Such data should allow us to address important issues such as mosaic evolution through concerted changes in the functionally related components of distributed systems, and the presumed increase in relative number of neurons in systems that increase in importance (Barton and Harvey, 2000 ; Barton, 2006 ).

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Tags: neuroscience, brain
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# Question
Title: Has there been any neuroscientific study of polydactyly?
I have been reading about polydactyly and found that surgery is only necessary in certain cases. It depends on way the extra digit on the hand or foot is attached.

For example, central polydactyly (a very rare situation, in which the extra digit is on the ring, middle or index finger) requires early osteotomy and ligament reconstructions to prevent deformities, such as angular growth deformities.

What I am wondering about is the most common type which is ulnar polydactyly also called postaxial polydactyly (the extra digit is on the ulnar side of the hand, thus the side of the little finger).

Neuroscience and psychology have studied the consequences for humans of losing a limb or other body parts, including documenting the pain caused by the phantom limb effect (usually explained as due to reorganisation of the brain’s representation of missing part).

What has neuroscience been able to establish regarding the extra sensorimotor information the brain would be dealing with? Can those with extra fingers use their extra digits with no problems with coordination etc?

# Answer
> 1 votes
The extra finger seen in polydactyly is often connected only with a bit of skin, but it may contain bone and even joints (Fig. 1). According to the Boston's children's hospital, the extra finger (or thumb) is normally surgically removed at a young age. Surgery is deemed necessary to prevent disruption of normal motor behavior early in life.

However, in some instances the additional finger is fully functional (Fig. 2). In a small study including two persons with polydactyly (each had 6 fingers on their hands) the authors (Mehring *et al*., 2019) concluded that

* The supernumerary finger (between thumb and index) is actuated by nerves and muscles not existent in 5-fingered hands;
* That the extra finger has a distinct cortical representation.
* Both subjects could manipulate the extra finger independently from the others and were in fact able to perform tasks single-handedly with the aid of the extra finger that the control subjects were unable to do barred with two hands.

The study describes a radial type of polydactyly. You are interested in the ulnar type (Fig. 3). Because I think the functionality of the finger is determined mainly by its mechanical functionality, innervation and cortical representation, I don't think then location on the hand is the determining factor. Hence I think that the Mehring *et al*. (2019) paper would apply to a ulnar case as well, barred the finger is fully developed.

Fig. 1. Types of polydactyly. source: Chopin *et al*. (2018)

Fig 2. Mechanically fully functional extra index finger. source: (Mehring *et al*. (2019)

Fig. 3. Types of polydactyly. source: Medical News Life Sciences

**References**
**-** Chopin *et al*., *Hand (NY)* (2020); **15**(3): 303–10
**-** Mehring *et al*., *Nature Comm* (2019); **10**: 2410

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Tags: neuroscience, cognitive-neuroscience, brain, sensory-perception, coordination
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# Question
Title: Can our beliefs change without reassessment or new evidence?
Can our beliefs change without reassessment or new evidence?

I think the strength of our beliefs can change, say from 90-95% as the day wore on. But do people, people with or without psychosis, start and stop believing things without reasons?

Suppose when I stop and think I always know something is impossible. Does that mean, even in the throes of some irrational behaviour (I sleep with my cheating wife again), I know it is, at least without encountering new evidence to the contrary?

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As has been pointed out, how we feel about things may change without new evidence, and our feelings can change what we believe. Does that mean we have to "reassess" something in order to be overwhelmed by emotion and new belief?

> Appraisal theory is the theory in psychology that emotions are extracted from our evaluations (appraisals or estimates) of events that cause specific reactions in different people. Essentially, our appraisal of a situation causes an emotional, or affective, response that is going to be based on that appraisal.

https://en.wikipedia.org/wiki/Appraisal\_theory

So e.g. if my newly discovered emotions of desire for my wife cause me to believe in her fidelity, is that always from an appraisal or reappraisal of some possibility (her fidelity, our future together...)

# Answer
> 4 votes
Anyone can choose to change their beliefs without reassessment or new evidence at any time.

These choices can be made without reasons, assessment and reassessment but at the same time, they **can** involve reasons, assessment and reassessment. Again, there is a choice on whether to assess and/or reassess.

There are many cognitive biases and heuristics which can be in play.

As an example, you can be presented with evidence contradicting preconceived ideas and initially change your beliefs. But, if you later apply, say, confirmation bias

> The tendency to search for, interpret, focus on and remember information in a way that confirms one's preconceptions

because you maybe don't want to believe the opposite, you may stick with the previous beliefs and go on the search for evidence to back up your preconceptions.

See the full list of cognitive biases and heuristics which can be in play because:

> Cognitive biases are systematic patterns of deviation from norm and/or rationality in judgment.

Above all, you cannot change your beliefs without wanting to.

For example, a devout Christian would not want to disbelieve something written in the Bible. But, if they were presented with contradictory evidence, they have a choice.

Do they just shrug it off and disbelieve that false information is in the good book? Or, do they at least start to doubt it's accuracies?

If they start to doubt the Bible, do they look at the evidence and believe it, or do they try to discredit it with stronger evidence, which backs the biblical account?

If they don't find it, what do they believe?

There may be unconscious biases in play with some beliefs (Marcelin, et al. 2019, Fiarman, 2016, Page, 2009) but, ultimately there are choices involved.

## References

Fiarman, S. E. (2016). Unconscious bias: When good intentions aren’t enough. *Educational Leadership, 74*(3), 10-15. http://files.partnership-academy.net/200002623-049ce0690e/Unconscious%20Bias\_Educational%20Leadership.pdf

Marcelin, J. R., Siraj, D. S., Victor, R., Kotadia, S., & Maldonado, Y. A. (2019). The impact of unconscious bias in healthcare: how to recognize and mitigate it. *The Journal of infectious diseases, 220*(Supplement\_2), S62-S73 https://doi.org/10.1093/infdis/jiz214

Page, A. (2009). Unconscious bias and the limits of director independence. *University of Illinois Law Review*, 237-294. https://heinonline.org/HOL/LandingPage?handle=hein.journals/unilllr2009&div=9&id=&page=

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Tags: belief
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# Question
Title: Do neurons involved in reflex movements process information or they just transmit a signal?
According to Reflex

> A reflex, or reflex action, is an involuntary and nearly instantaneous movement in response to a stimulus. A reflex is made possible by neural pathways called reflex arcs which can act on an impulse before that impulse reaches the brain.

Is the magnitude, direction, etc. of this response evaluated somewhere in some type of neurons? Is there information processing in relation to, for this type of stimulus magnitude, it's evaluated which magnitude of response should be triggered by a neuron, or does the stimulus simple activate a neural pathway which activates a fixed response and the difference in the response is the result of how many neural pathways the stimulus activate?

To make an analogy, do reflexes work like turning several light switches for more or less light, or like inputing data into a program for different kind of responses?

# Answer
> 2 votes
**Short answer**
Reflex arcs can perform basic processing operations like inversion, summation and integration.

**Background**
Reflexes include a wide variety of responses and in fact an all-inclusive definition seems to be lacking. Mann defines a reflex on their website as

> \[A r\]elatively stereotyped movement or response elicited by a stimulus applied to the periphery, transmitted to the central nervous system and then transmitted back out to the periphery

In textbooks, reflex arcs are often depicted as simple on/off switches, and the one underlying the **knee jerk reflex** is one that is often cited (Fig. 1).The quadriceps is key here. When it contracts it extends the angle of the knee joint by raising the lower leg. Tapping the patellar tendon momentarily stretches the quadriceps muscle and causes the sensory receptor of the muscle, called a spindle fiber, to send a signal along the afferent neuron to the spinal cord. This causes the efferent neuron to return a signal to the quadriceps muscle to contract and lift the lower leg. This action resists the initial stretch and is a classic example of negative feedback.

The knee jerk reflex arc in Fig. 1 is a so-called **monosynaptic arc**; just a single synapse connects the sensory and motoneuron. As far as I know, this simple circuit is more like an on/off switch; tap the tendon and the neurons start firing. However, if you tap it softly, nothing may happen, either because the spindles' signal is too low to reach threshold of the afferent neuron, or too little afferent neurons are recruited for a visible jerk to occur.

There are also disynaptic and polysynaptic reflex arcs due to the presence of 1 or more interneurons within the spinal cord that connect the sensory and motoneuron.

The interneuron in a disynaptic arc is often inhibitory. In this case the excitatory input from the sensory neuron is 'reversed' into an inhibitory response, thereby for instance reducing muscle tone instead of increasing it. In terms of **logical circuits** the interneuron would act as a 'NOT' (inverter) port. In that sense, the reflex arc performs a type of very basic **Boolean** processing (Fig. 2).

It is also known that for instance clasping the hands together and pulling on one of them (the **Jendrassik maneuver**) the tendon tap reflex is increased in magnitude. So somehow the reflex arc is subject to integration of neuronal inputs, also akin to a processing step.

Likewise, reflex arcs can be subject to enhancement by repetitive stimuli, akin to a summation processing step somewhere in the arc (Eccles & Sherrington (1930); Johnson *et al*., (2017)).

Reflex arc of the knee jerk (patelllar reflex). source: Wikipedia

Fig. 2. The same knee jerk circuit as Fig. 1, but now with the accompanying disynaptic reflex arc drawn as well. This arc releases muscle tone of the antagonistic flexor muscle, such that the extensor muscle activated by the knee jerk can freely lift the leg. source: Human Physiology Academy

**Reference**
**-** Eccles & Sherrington, *J Physiol* (1930); **69**(1): 1–28
**-** Johnson *et al*., *Front Neural Circuits* (2017); *11*: 83

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Tags: neuroscience, neurophysiology
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# Question
Title: Is Tinnitus caused by damage to the dorsal cochlear nucleus (DCN) or Auditory Cortex, which can be repaired?
> It is well known that loud noises can lead to hearing problems such as temporary hearing loss or tinnitus (ringing in the ears) and even permanent hearing loss. But this is the first time scientists have been able to identify damages to nerve cells as a result of noise exposure.

The research allows us to understand the pathway from exposure to loud noises to hearing loss. Dissecting the cellular mechanisms underlying this condition is likely to bring a very significant healthcare benefit to a wider population. The work will help prevention as well as progression into finding appropriate cures for hearing loss", said the lead researcher Dr. Martine Hamann, from the University of Leicester in the UK. (Hear-it.org, 2014)

Listening to tailor-made notched sound or notched music reduces tinnitus loudness and tinnitus-related auditory cortex activity (Okamoto, et al., 2010)

> **Abstract**
> Maladaptive auditory cortex reorganization may contribute to the generation and maintenance of tinnitus. Because cortical organization can be modified by behavioral training, we attempted to reduce tinnitus loudness by exposing chronic tinnitus patients to self-chosen, enjoyable music, which was modified (“notched”) to contain no energy in the frequency range surrounding the individual tinnitus frequency. After 12 months of regular listening, the target patient group (*n* = 8) showed significantly reduced subjective tinnitus loudness and concomitantly exhibited reduced evoked activity in auditory cortex areas corresponding to the tinnitus frequency compared to patients who had received an analogous placebo notched music treatment (*n* = 8). These findings indicate that tinnitus loudness can be significantly diminished by an enjoyable, low-cost, custom-tailored notched music treatment, potentially via reversing maladaptive auditory cortex reorganization.

(Image Source: Notched Music Therapy App for Android)

The hear-it.org website at the paged linked above says:

> Loud music played on earphones causes hearing loss by having a similar effect on nerves as multiple sclerosis, research finds. The research shows that noise levels above 110 decibels strip insulation from nerve fibers carrying signals from the ear to the brain. Loss of the protective coating, called myelin, disrupts electrical nerve signals.

Looking for the source, it seems to be coming from John Von Radowitz's article within The Independent newspaper (2012), stating that:

> Loud music played on earphones causes deafness by having a similar effect on nerves as multiple sclerosis (MS)

With both articles mentioning Dr. Martine Hamann from the University of Leicester, I found that she was involved with three studies in that year.

The article which seems to be related is Pilati, et al. (2012), which states within the abstract:

> Here we investigate mechanisms contributing to excitability changes in the dorsal cochlear nucleus (DCN) shortly after exposure to loud sound that produces hearing loss. We show that acoustic overexposure alters synaptic transmission originating from the auditory and the multisensory pathway within the DCN in different ways. A reduction in the number of myelinated auditory nerve fibers leads to a reduced maximal firing rate of DCN principal cells, which cannot be restored by increasing auditory nerve fiber recruitment. In contrast, a decreased membrane resistance of DCN granule cells (multisensory inputs) leads to a reduced maximal firing rate of DCN principal cells that is overcome when additional multisensory fibers are recruited. Furthermore, gain modulation by inhibitory synaptic transmission is disabled in both auditory and multisensory pathways. These cellular mechanisms that contribute to decreased cellular excitability in the central auditory pathway are likely to represent early neurobiological markers of hearing loss and may suggest interventions to delay or stop the development of hyperactivity that has been associated with tinnitus.

The following is also in the article:

Acoustic overexposure (AOE):

* induces hearing threshold elevations (shifts of hearing thresholds of 20–30 dB sound pressure level were observed for frequencies above the frequency used during the AOE protocol),
* decreases fusiform cell excitability,
* down-regulates auditory nerve (AN) and multi-sensory (MS) synaptic transmission to fusiform cells (FCs)
* reduces FC maximal firing rate upon AN stimulations
* decreases the number of myelinated AN fibres in the cochlea
* reduces FC maximal firing rate upon MS input stimulation and
* decreases granule cell membrane resistance
* disables FC gain control by inhibitory synaptic transmission

## Auditory Nerve stimulations

>

> AN stimulations (25 V, 0.3 Hz) trigger smaller Excitatory post-synaptic potentials after AOE (blue)). Membrane potential was −70 mV. Histogram summarizes excitatory post-synaptic potential amplitudes measured at similar stimulating voltages in unexposed (25 ± 4 V, *n* = 4) and exposed conditions (28 ± 2 V, *n* = 6). * *P* \< 0.05,

>

> In unexposed condition (black), AN stimulations (40 V, 0.3 Hz) trigger action potentials in a FC (membrane potential of −60 mV). After AOE (blue), AN stimulations (40–45 V, 0.3 Hz) fail to trigger action potentials.

## Multisensory stimulations

>

> MS stimulations (15 V, 0.3 Hz) trigger smaller excitatory post-synaptic potentials after AOE (blue). Membrane potential was −70 mV. Histogram summarizes excitatory post-synaptic potential amplitudes measured at similar stimulating voltages in unexposed (16 ± 1 V, *n* = 8) and exposed conditions (19 ± 2 V, *n* = 6). \** *P* \< 0.01: unpaired t tests.

>

> In unexposed condition (black), MS stimulations (20 V, 0.3 Hz) trigger action potentials in a FC (membrane potential of −60 mV). After AOE (blue), higher stimulation voltages (25 V, 0.3 Hz) are required to trigger an action potential.

Not having a background in neurology, I am wondering if altered synaptic transmission originating from the auditory and the multisensory pathway within the DCN equates to brain damage or is the altered synaptic transmission caused by information received from the damaged cochlea?

**In other words, has it really been found that the cause of Tinnitus is brain damage which can be repaired through playing sounds or music with a "notch" in specific frequency spectrums?**

## References

Hear-it.org (2014) *Loud music damages the nerves in the brain* \[Online\]
Available from: https://www.hear-it.org/loud-music-damages-nerves-brain

Okamoto, H., Stracke, H., Stoll, W., & Pantev, C. (2010). Listening to tailor-made notched music reduces tinnitus loudness and tinnitus-related auditory cortex activity. Proceedings of the National Academy of Sciences, 107(3), 1207-1210.
DOI: 10.1073/pnas.0911268107

Pilati, N., Ison, M. J., Barker, M., Mulheran, M., Large, C. H., Forsythe, I. D., ... & Hamann, M. (2012). Mechanisms contributing to central excitability changes during hearing loss. *Proceedings of the National Academy of Sciences*, 109(21), 8292-8297.
DOI: 10.1073/pnas.1116981109

Radowitz J. V. (2012). *Loud music played on headphones causes deafness by having a similar effect on nerves as multiple sclerosis (MS) - The Independent*
Available at: https://www.independent.co.uk/life-style/health-and-families/health-news/loud-music-on-headphones-causes-deafness-by-having-a-similar-effect-on-nerves-as-ms-8091683.html

# Answer
**Short answer**
Sensory tinnitus is not caused by brain damage, but is due to degeneration of peripheral auditory neurons, and specifically the hair cells in the inner ear.

**Background**
Tinnitus can be either somatic or sensory in nature. You are enquiring on the latter type here.

Sensory tinnitus is generally associated with sensorineural hearing loss (HL), meaning that the mechanosensory cells, the hair cells (HCs) in the inner ear (cochlea) have been damaged. When this is a permanent ailment, the auditory nerve fibers (ANFs) connected to the HCs may degenerate and the auditory cortex becomes deprived of stimuli. A commonly encountered hypothesis is that the deafferented cortical cells start to actively seek new input (it's also possible that something similar happens in brainstem auditory nuclei; you could perhaps call this "damage" but it would be better described as dysfunction). They might be recruited for visual processing in the process, or they may actually generate endogenous activity on their own. Typically this results in tinnitus corresponding to the frequencies that are lost in the cochlea. This is caused by the tonotopy that is maintained from cochlea up to the primary auditory cortex (for a review see Møller (2016).

To get to your question - the auditory cortex and DCN are *not* damaged by sensorineural HL. The DCN receives input from the AN. While the HCs and AN are known to degenerate after prolonged HL, more central nuclei and cortical structures do not. They may become remapped but they won't regress.

**Therapies for tinnitus** often involves the fitting of hearing aids to reestablish input to the auditory system, or masking the sounds that are generated internally by external stimuli, such as pink noise or simply listening to music. Often psychologists get involved in severe cases to deliver coping strategies to the patient. Severe tinnitus cases are associated with considerable suffering, depression and increased chance of suicide.

Early surgical interventions included the severing of the AN, as they thought tinnitus arose peripherally. This made the situation, obviously, often only worse. Currently cochlear implantation is also considered experimentally to reestablish input to the auditory system by means of electrical stimulation (Baguley & Atlas, 2007).

<sub>**References**
**-** Baguley & Atlas, *Progr Brain Res* (2007);**166**: 347-55
**-** Møller, Int J Otolaryngol (2016): 2830157</sub>
> 5 votes

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Tags: perception, brain, hearing, brain-injury, tinnitus
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# Question
Title: Can awareness directly influence activity of our immune system in certain regions?
Recently I talked with a colleague about general physical health. He revealed to me that he had not visited a dentist in 13 years. I followed up and asked the obvious if he has any complications with caries, gum disease etc. He denied having any problems. 2 days after our talk I saw him again and the left side of his face was swollen. He told me that 1d after our talk he experienced severe pain and swelling stemming from one of his teeth.

The question is, can awareness of bodily functions influence immune function of the body? Could our talk about dental health triggered an immune reaction? Are there any studies which have investigated this? I'm aware of mind-body connection through hormones, but can awareness directly influence the immune system. For example, can activity of the immune system in certain regions be increased by placing them at the center of awareness?

# Answer
> 1 votes
The short answer is no, you cannot direct immune responses to specific areas, but you can boost or lower immune responses throughout the body via mood and mindfulness.

What you are talking about here is Mind Over Matter, and while many poo-poo the idea, there are cases where it does seem to work.

While the link provided isn't directly related to the question *per se*, it gives you an incite into some areas of *mind over matter* that have been studied.

If you are familiar with the movie, Patch Adams (1998), it told the story of the real Patch Adams (Hunter Doherty "Patch" Adams) who founded the Gesundheit! Institute in 1971.

Hunter Adams,

> urges medical students to develop compassionate connections with their patients. His prescription for this kind of care relies on humor and play, which he sees as essential to physical and emotional health.

The way he has personally seen this is that this kind of care speeds up the recovery process and patients can go home earlier. D'Acquisto, F. (2017) found this to be the case and called for a new scientific area of research called **affective immunology**.

> Studies over the last few decades have provided sufficient evidence for similarities and overlaps between the immune and emotional responses. The majority of living beings use both systems to adjust dynamically to the ever-changing conditions of the external environment. Both systems can either be protective for the body if kept under control or detrimental to it when they are in disarray. Despite the vast body of knowledge we have gathered on the links between these two systems, there have been very few attempts to move this area of research from bench to bedside. This might be due to many causes, including the perceived impression that the world of immunology and that of psychology or psychiatry are completely different, if not polar opposites.
>
> One of the main aims of this review is to help overcome this skepticism and to highlight the importance of these similarities in clinical settings.

The *New Scientist* magazine highlighted that you can heal yourself by thinking positive.

> Go on, try to convince yourself, because realism can be bad for your health. Optimists recover better from medical procedures such as coronary bypass surgery, have healthier immune systems and live longer, both in general and when suffering from conditions such as cancer, heart disease and kidney failure Aspinwall & Tedeschi, 2010

They also highlighted that

> There is some evidence that meditation boosts the immune response in vaccine patients and people with cancer, protects against relapse in major depression, soothes skin conditions and even slows the progression of HIV.

Fiacco, et al. (2017) conducted a cursory study into the effect of mindfulness over the immune response, highlighting that stress has been linked to diseases such as type 2 diabetes and rheumatoid arthritis. But, the study didn't really provide any strong evidence to back the theory, although:

> Participants with a higher mindfulness score revealed a more positive mood profile. Further research is needed to investigate the effect of trait mindfulness on other immune parameters.

This is probably due to the cursory nature of the study.

## References

Aspinwall, L. G., & Tedeschi, R. G. (2010). The value of positive psychology for health psychology: Progress and pitfalls in examining the relation of positive phenomena to health. *Annals of behavioral medicine, 39*(1), 4-15. https://doi.org/10.1007/s12160-009-9153-0

D'Acquisto, F. (2017). Affective immunology: where emotions and the immune response converge. *Dialogues in clinical neuroscience, 19*(1), 9. https://doi.org/10.31887/DCNS.2017.19.1/fdacquisto

Fiacco, S., Lozza, N., Kübler, U., Ehlert, U., Scheiwiller, M., Rüttimann, C., ... & La Marca, R. (2017). Mind over matter–The association between mindfulness, acute stress and the immune response. *Psychoneuroendocrinology, 83*, 16. https://doi.org/10.1016/j.psyneuen.2017.07.281

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Tags: health-psychology
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# Question
Title: Can unconscious wishes be fulfilled via actions based on conscious or unconscious identification?
Suppose I unconsciously want to sleep with my mother (I'm not sure I do: it's just a hypothetical). Can that unconscious wish to do so be fulfilled by sleeping with yours, if I consciously or unconsciously identify with you?

What is the word for that process?

# Answer
Catharsis is the technical term for the "release" of an unconscious conflict.

According to the definition, conflict may or may not be "resolved" if acted upon. For instance, consider someone who is primarily homosexual, has a brief homosexual encounter after coming out of the closet, but then proceeds to marry someone of the opposite sex (because that is what their family wants them to do).
> 3 votes

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Tags: unconscious, freud
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# Question
Title: Why do psychologists tend to associate guilt with auditory admonition?
Can you please expound the sentence that I marked with red lines? The green underlie refers to Wolfram Eberhard's 1967 book *Guilt and Sin in Traditional China*, page 12. But my library is closed because of COVID.

Axel Schuessler, *ABC Etymological Dictionary of Old Chinese* (2007), p 188.

# Answer
The book is available free online in Open Library and the Wolfram Eberhard reference seems to refer to

> Helen Lynd, *On Shame and the Search for Identity"* (New York, 1961), p. 207

The 1961 copy is not on Open Library, but there is a 1st edition copy from 1958. **Please read from the bottom paragraph on page 207**.

Among others, the book points out that guilt involves

> exposure of a misdemeanour, with emphasis to whom exposed; exposure to something that should be hidden in a closet.

The book then compares it to Erik Erikson’s 8 life stages of man, originally put together in 1950 in his book *Childhood and Society*, which I covered in an answer to another question about child development.
> 5 votes

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Tags: hearing
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# Question
Title: Do women see the phallus with the same amount of sexual excitement as a man seeing breasts?
Heterosexual men love to ogle breasts; the bigger(usually) the better and often are one of the first things they look at. Women have more erroneous zones than men and they don’t really have the pleasure of seeing the male penis since it is always covered up. So do women get the same charge out of seeing a phallus like a man would seeing breasts?

# Answer
### No, men and women process sexual stimuli differently.

Put succinctly, men are aroused by seeing sexual things, but women typically are not. Women, by contract, are more aroused by sexual relationships, which is why the female equivalent of a pornographic movie is a romance novel.

Here's a quote on the topic from an article on Psychology Today, which is in turn quoting the book *A Billion Wicked Thoughts* by Ogi Ogas and Sai Gaddam:

> "Women respond to a truly astonishing range of cues across many domains. The physical appearance of a man, his social status, personality, commitment, the authenticity of his emotions, his confidence, family, attitude toward children, kindness, height, and smell. . . . Unlike men, who become aroused after being exposed to a single cue, women need to experience enough simultaneous cues to cross an ever-varying threshold. Sometimes, just a few overwhelming cues can take a woman there. Other times, it takes a very large number of moderate cues ... For women, no single cue is either necessary or sufficient" (p. 212).
> 1 votes

# Answer
This goes along with Bem's (1996) developmental theory that proposes that the exotic becomes erotic.

More specifically, this is called the EBE (exotic becomes erotic) theory.

Generally speaking, EBE unravels the biological correlates of sexual orientation. More specifically, Peplau et al. (1998) explains that the theory proposes

> that adults are erotically attracted to the gender-based class of peers (males or females) who were dissimilar or unfamiliar to them in childhood.

This theory has been criticized as having several limitations. For example, Peplau et al. (1998) explains that EBE can not be applied to gender diverse individuals

> Bem's conceptualization of erotic desire and his analysis of gender nonconformity illustrate this problem.

Moreover, the theory is also criticized for being biased towards the perceptions of men, discounting perceptions of women and gender diverse.
> 0 votes

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Tags: sexuality, sex-differences, arousal
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# Question
Title: Empath vs. Covert Narcissist in high conflict context
Is it really possible to spot a narcissist under fog of war? I.e., apart from the lenses of high conflict, is there any other major difference between an empath and a covert narcissist?

To the layman, ego is described as good or bad. The good ego is the empath who, through his own ideals, cares about others, and wants others to care too, even if that means isolating the "covert narcissists" for health reasons. The bad ego is the covert narcissist who pretends to care, but has no visible ideals other than winning by hurting others, and does not receive feedback.

I believed all this until I read *High Conflict* by Amanda Ripley. From the publisher:

> When we are baffled by the insanity of the “other side”—in our politics, at work, or at home—it’s because we aren’t seeing how the conflict itself has taken over.
>
> That’s what “high conflict” does. It’s the invisible hand of our time. And it’s different from the useful friction of healthy conflict. That’s good conflict, and it’s a necessary force that pushes us to be better people.
>
> High conflict, by contrast, is what happens when discord distills into a good-versus-evil kind of feud, the kind with an *us* and a *them*. In this state, the normal rules of engagement no longer apply. The brain behaves differently. We feel increasingly certain of our own superiority and, at the same time, more and more mystified by the other side.

Now I reread the preceding paragraph and see no difference apart from the lenses of high conflict: one side has ideals and the other doesn't. One side listens and the other doesn't. But over time, I and the subjects in AR's book have found that solving the high conflict gets us to listen to the other side and see their ideals (curing the pathology without bothering to *agree* on the specific ideals underlying high conflict). High conflict seems to explain common psychological disagreements, for example each side sees their own rage as empathic but the other side's rage as narcissistic. Same pathology, different lens.

So, I am starting to wonder: apart from high conflict, is there really any major difference between an empath and a covert narcissist, and, if so, how common is that difference?

# Answer
The differences between narcissist and empath definitely go beyond any broader conflict. A narcissist is self-aggrandizing, envious, always worried about how others perceive him, feeds off others' praise, takes credit for other people's work, has poor interpersonal boundaries, and always wants to be the one hitting the ball. An empath would be more of a collegial team player.
> 0 votes

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Tags: personality-disorder, empathy, conflict
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# Question
Title: What is the neuroscientific difference between learning/memorizing and understanding in the brain?
I'm trying to understand how our brains - neurons or other chemical processes work in regards to learning/ memorizing and understanding.

I found a lot of "theoretical" discussions on the topic- e.g. learning is memorizing, and understanding is knowing how to apply something. But none of them talked about the actual process in the brain.

# Answer
According to this fascinating chapter, learning, memorization, and understanding are all related.

You might want to check it out. It basically assumes learning to be a process that involves coordination of the various cognitive sub-processes.
> 1 votes

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Tags: neuroscience, learning, memory, brain
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# Question
Title: Are there results on the null hypothesis of the "surgeon operating on my son" question?
There is a common question used to demonstrate the power of implicit assumptions about gender roles in our society.

Including it here for reference: A man and his son had a terrible car accident and were rushed to the hospital. The man died on the way, but the son was still barely alive. When they arrived, a surgeon was called in to operate. Upon seeing the young boy, the surgeon said, “I can’t operate – this is my son.”

Most people have difficulty thinking of the possibility that the surgeon is the son's Mother.

This riddle strikes me as having elements of the priming experiments whereby subjects primed with certain words perform better/worse in word-stem completion tests, intermixed with the social expectations of our culture. Here the "priming" would be using the male "father", "boy", and "son" throughout the question but asking for a female "mother" as the answer.

I was trying to find results on some sort of "control group" experiment to try and isolate the societal expectations element. Something like subjects being asked the same riddle but with a mother and daughter in a crash and the father a surgeon, or where it's the father and daughter in a car crash.

The only alternative I've seen is about "mother and daughter in crash, father is nurse" which is again combining the two effects.

N.b. I'm expect the priming effect is probably small, I just wanted to know by how much.

# Answer
The implicit-association test is a larger example of the same phenomenon. Words are paired that are congruent or incongruent with societal expectations; incongruent pairs take most people longer to match.

A caution on this test it is often used to measure bias in individuals and for some as a surrogate for bigotry. However, it does not account for intentional methods to avoid biased action, it only measures the "automatic", involuntary biases imposed by exposure to culture. It should be instructive to test-takers how the results might shape their behaviors in every day life, but shouldn't be taken as a measure of "how sexist" or "how racist" someone is. It is also not apparent that *individual* results are informative; population-level results trend with population-level biases, but individual performance on the test is not a valid way to find "who is more biased" or anything like that.
> 3 votes

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Tags: cognitive-psychology, measurement
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# Question
Title: How is the memory compressed when moving from the hippocampus to the PFC?
I have recently been intrigued by memory. I found that the hippocampus stores new memories. In sleep, the newly formed memories are moved to the neocortex.

I was curious about how this transition occurred, so I searched it up, and got this result. The website says that there is a part in the hippocampus called CA1, that compress the memory before it is transferred through connections to the prefrontal cortex. This can happen in Sleep or during Awakeness with Sharp-wave-ripples.

Please correct me if my interpretation is wrong. I would also like to know how the memory is compressed. And when the PFC receives the signal, I would also like to know how they expand the memory again.

Thank you.

# Answer
Asking about compression in this manner it seems you may be over-applying a computer analogy to the brain. The computer model of the brain is an existing resource here that I recommend reading.

As far as this paper itself, it's talking about associative memory in particular, which the hippocampus is highly involved in. The paper you link to is specifically talking about sequence replay, which is where an association (=memory) is built out of a sequence of neuronal activations. For example, you might represent a path through a maze or grocery store as a sequence of spatial navigation steps: moving straight through a corridor, taking a left turn at the milk, following the trail of eggs to the cheese.

In hippocampus, you'll see "replay" of the neural signatures of these sorts of steps. If you look at activity in hippocampus while a rodent runs through a maze, you'll find those same patterns of activity *repeat* later on when the rodent is just sitting there passively, or while they sleep.

However, these replay events need not take place at the same time scale as the original behavior. You can play this in your own memory, too: maybe it takes you 2-3 minutes to walk into the grocery store and find the cheese, but if you're retracing your steps later you can probably think about the path you took over just a couple of seconds. You also need not think about it in the *forward* sequence, you can just as well work backwards from your destination and "retrace your steps"; replay in the hippocampus will do this as well.

When these authors talk about *compression* in ripple events, this is the type of compression they mean: time compression, not a data compression algorithm like Lempel-Ziv. Of course, time is quite a valuable resource in the brain or two a behaving animal, so time compression can also be important for reasons of efficiency, but it's not the sort of thing that necessarily needs to be "decompressed" back to something useful. The associations you might form over several minutes doing some task can be transmitted between brain areas in just seconds or milliseconds. Here's a paper they cite about the "fast-forward" compression:

Euston, D. R., Tatsuno, M., & McNaughton, B. L. (2007). Fast-forward playback of recent memory sequences in prefrontal cortex during sleep. science, 318(5853), 1147-1150.

The paper you link to is a research paper; when learning about a new concept I'd highly recommend looking at relevant *review* papers, which combine many research results together in a form that's usually more digestible for someone new to the field. Research papers themselves often refer to earlier review papers to ground their results. Here are some of those from this paper that you might look at:

Diekelmann, S., & Born, J. (2010). The memory function of sleep. Nature Reviews Neuroscience, 11(2), 114-126.

Dudai, Y., Karni, A., & Born, J. (2015). The consolidation and transformation of memory. Neuron, 88(1), 20-32.

Eichenbaum, H. (2017). Prefrontal–hippocampal interactions in episodic memory. Nature Reviews Neuroscience, 18(9), 547-558.

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and some groundbreaking original papers as well, where you might first focus on their introductions to understand thinking in the field, and then look at their specific results next:

Jahnke, S., Timme, M., & Memmesheimer, R. M. (2015). A unified dynamic model for learning, replay, and sharp-wave/ripples. Journal of Neuroscience, 35(49), 16236-16258.

Karlsson, M. P., & Frank, L. M. (2009). Awake replay of remote experiences in the hippocampus. Nature neuroscience, 12(7), 913-918.

Kenet, T., Bibitchkov, D., Tsodyks, M., Grinvald, A., & Arieli, A. (2003). Spontaneously emerging cortical representations of visual attributes. Nature, 425(6961), 954-956.

Peyrache, A., Khamassi, M., Benchenane, K., Wiener, S. I., & Battaglia, F. P. (2009). Replay of rule-learning related neural patterns in the prefrontal cortex during sleep. Nature neuroscience, 12(7), 919-926.

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(paper that prompted this question)

Liu, X., & Kuzum, D. (2019). Hippocampal-Cortical Memory Trace Transfer and Reactivation Through Cell-Specific Stimulus and Spontaneous Background Noise. Frontiers in computational neuroscience, 13, 67.
> 2 votes

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Tags: neuroscience, memory, hippocampus
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# Question
Title: Are there any mental activities that can be detrimental for intelligence?
It is well known that we get better at the things we practice, but is it possible to stimulate the brain with activities in such a way that general or specific intelligence is weakened? Also, are there skills that can be practiced that have been proven to weaken other skills?

# Answer
While not necessarily lowering of one's IQ, two phenomena potentially detrimental to one's capacity for future learning and problem solving are **Einstellung Effect** and **Compartmentalisation**.

In the Einstellung Effect, an initial framing or initial experience with a particular type of problem or situation sets into habit a fixed way of behaving. Later, when a situation arises which evokes the same mental classification due to having a similar appearance, the person is left pursuing a suboptimal or perhaps dead-end approach. In other words, the person knows enough to be dangerous but may lack the insight needed to see this deficiency.

If one goes too long without encountering sufficient novelty, one's mind may become fixed. Neurologically this occurs because the same simple path is traversed too many times, very much like in addiction. Perhaps one solution is to move forward with one's learning and skills, never staying too long on the same level, always taking on new challenges, even when initial failure is likely. **Staying with what is known may be comfortable, but staying too long closes the mind.**

In Compartmentalisation, thoughts which conflict on some level of abstraction are separated into mutually exclusive mental boxes. A common example is separating work life from family life. If one partakes too readily in compartmentalising, however, the mind may become fragmented. The drive for compartmentalising is to escape cognitive dissonance, which, if done in excess, can slowly erode one's mental stability while dividing one's worldview into two or more inherently contradicting subsets. With standing contradictions, one's broken foundations may prevent the successful pursuit of higher truths.

Though not always practical, one solution to excessive compartmentalisation is to re-arrange one's life so as no longer to feel compelled to keep things separate. For example, one might find a career in better alignment with one's values. Another solution is to break down the mental barriers to integration by finding a more truthful, more encompassing worldview. One's existing perspective may have fallen prey to the Einstellung effect, having been set early in life without enough experience to see the holes.
> -1 votes

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Tags: intelligence
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