# Question
Title: How does displaying existing votes to a poll influence subsequent voting behaviour?
Some polls involve a question where the existing votes received for each response option are displayed. I have heard that on such polls the existing votes influence the answers provided by subsequent respondents.

* Is it true that the displayed results influence voting behaviour by subsequent respondents?
* How does it influence the respondents?
* How strong does it influence the respondents?
* Do smart respondents resist this influence?

# Answer
> 3 votes
Yes, this does happen. It is called an information cascade. From Wikipedia:

> An information (or informational) cascade occurs when people observe the actions of others and then make the same choice that the others have made, independently of their own private information signals.

There is lots of evidence that people will abandon their own opinions and conform to the opinion of the masses (see the Asch conformity experiments). Depending on the domain, there could be many explanations for this. A non-exhaustive list includes:

* the decision-maker may be uncertain and believe that the masses, on average, will make the correct decision
* the decision-maker may want to avoid being on the 'losing' end of things (social pressure)
* the decision-maker may want to avoid responsibility
* the decision-maker may not want to expend cognitive resources making a difficult decision

**Do smart respondents resist this influence?**

My brief research did not turn up any articles on the effect of intelligence on susceptibility to this effect. However it should be noted that there is no reason a "smart" voter should resist a cascade, and in fact it may be smarter to *conform* to the cascade. Consider the situation where your favored candidate is losing in the polls. Your second-favorite and least-favorite candidates are in a dead heat for first place. A rational voter might actually vote for his second-favorite candidate to prevent his least-favorite candidate from winning.

**Does this happen in real-life major governmental elections?**

While information cascades certainly exist, I'm not aware of any proof that an information cascade has affected a real-world, major governmental election. Which isn't to say this hasn't happened, only that the evidence is contentious. (It's generally hard to *prove* this kind of stuff outside a laboratory.)

Battaglini (2004) states:

> Despite the fact that much attention in the theoretical literature has been focused on simultaneous voting mechanisms, many important decisions are actually taken in sequential mechanisms. This is certainly the case of presidential primaries, and of roll-call voting in legislatures; but it is often the case that even mechanisms that are supposed to be simultaneous, are not in practice, because late voters generally have access to exit polls and other information describing the choice of early voters.1 A famous example is the 1980 Presidential election in which the news that Ronald Reagan was winning by a landslide changed expectation “suddenly and dramatically.”2 The “popular” intuition, therefore, is that because of bandwagon eﬀects, timing matters. This view is also supported with strong historical and experimental evidence (see Hung and Plott, 2000, and Morton and Williams, 2000a and 2000b).

This literature is not my area of expertise, but this article seems relevant and provides several pertinent citations:

> Battaglini, M. (2005). Sequential voting with abstention. Games and Economic Behavior, 51(2), 445-463. PDF

---
Tags: decision-making, political-psychology
---


title: Can sleep become addictive?

text:
# Question
Title: Can sleep become addictive?
Can a person become dependent on sleeping (more than they otherwise physically *need*) in a way that fits the definition of addiction, in the same way some psychology professionals may describe a person as being addicted to other standard needs, such as food, work, exercise?

If so, is there a way to determine whether the "need" for more sleep is due to actual physical needs or due to an addictive response?

Have there been any studies on this topic?

# Answer
> 10 votes
Not aware of any studies on this topic. I think this is a tricky question because of the nature of sleeping.

Hypersomnia does not fit in with physiological nor psychological dependence because of the following (from the proposed DSM-V revision, but similar enough to the DSM-IV-TR) symptom:

"The sleep periods are non-restorative (unrefreshing) or so prolonged in length that this causes clinically significant distress or impairment in social, occupational, or other important areas of functioning."

Now, sleep would not fit in with the class of substance-related disorders. I cannot see one having impaired control over or compulsive use of sleep. Can one really derive that much pleasure, and thus, a reward response from sleep? Would one have a tendency to keep increasing the dose, to chase "a high"? Abrupt cessation of sleep after excessive "use" may trigger negative feelings but if one were to, say, give the sleep-craving individual stimulant medication, I doubt serious withdrawal effects will take place.

The only proposed behavioral addiction for the DSM-V (at least I think at this point) is Gambling Disorder, or pathological gambling. The proposed criteria are as follows.

A. Persistent and recurrent maladaptive gambling behavior as indicated by five (or more) of the following:

1. is preoccupied with gambling (e.g., preoccupied with reliving past gambling experiences, handicapping or planning the next venture, or thinking of ways to get money with which to gamble
2. needs to gamble with increasing amounts of money in order to achieve the desired excitement
3. has repeated unsuccessful efforts to control, cut back, or stop gambling
4. is restless or irritable when attempting to cut down or stop gambling
5. gambles as a way of escaping from problems or of relieving a dysphoric mood (e.g., feelings of helplessness, guilt, anxiety, depression)
6. \[Not relevant.\]
7. lies to family members, therapist, or others to conceal the extent of involvement with gambling
8. has jeopardized or lost a significant relationship, job, or educational or career opportunity because of gambling
9. \[Not relevant.\]

Can a psychological dependence on sleep fit in with the above criteria if one were to mold it to pertain to "pathological" sleeping?

I could not think of analogous "Sleep Addiction" criteria to match that of Gambling Addiction's A-6/A-9 symptom points, but from the above, it appears that a psychological dependence /can/ apply to a dependence on sleep(ing). From this loose argument alone.

1. Preoccupied with sleep. \[Sure.\]
2. Needs get an increasing amount of hours of sleep to achieve the same response. \[Eh. I was thinking "resorts to increasing doses of sedatives to achieve longer periods of sleep" but felt that ventured into substance abuse territory.\]
3. Has repeated unsuccessful efforts to control, cut back, or stop (ha) \[excessive\] sleep. \[Sure, why not.\]
4. Is restless or irritable when attempting to cut down on sleep. \[Can see this happening.\]
5. Sleeps as a way of avoiding problems or of relieving dysphoric mood. \[Most definitely, this symptom reminds me of some subtypes of Major Depressive Disorder. But I digress.\]
6. Lies to family members, others, to conceal the extent of excessive sleep. \[Why not.\]
7. Has jeopardized or lost a significant relationship, job, or educational or career opportunity because of excessive sleep. \[Can easily see this.\]

If I can interject my own opinion on the matter, I just cannot see anyone developing a physical need for sleep. Our basic biological or evolutionary make-up does not allow for that, I feel. But I know little about, say, narcolepsy - but to my knowledge they find their excessive sleepiness unwanted and detrimental. Nor can I see potential for one to become psychologically dependent or addicted to sleep. I just can't see someone deriving pleasure from more and more sleep.

# Answer
> 9 votes
"Nor can I see potential for one to become psychologically dependent or addicted to sleep."

I believe someone can become "psychologically dependent on sleep".

I am 47 and have used sleep for 40 years to escape from life. I typically sleep 4-6 hours too much each day. I don't really physically need this sleep, since I then am often awake the next night for oversleeping that day, or I get a very strange tingling feeling in my body when I am forcing myself to sleep more and my body simply can't sleep any more. Also, I wake up after a normal 8hrs, feel like I can't face the day and force myself to go back to sleep with more breaks of waking up and forcing myself back to sleep for the next 4-5 hours.

My sleep gets in the way of living a full day and being productive. When I finish my day, I am frustrated that I lost so many hours to sleep.

I have tried everything for the last 25 years to address this. I have tried 7 years of psychotherapy, personal will power, all kinds of sleep and activity schedules, full physical examinations, talking with a sleep specialist, etc.

I always seem to eventually drift back into using sleep as a way of getting out of life.

I am generally an intelligent, capable person, have a college degree, reached a decent level professionally, travelled around the world, etc. I look like a normal person but the sleep problem makes functioning difficult.

I have had some childhood trauma, depression, anxiety which I have worked with extensively with psychotherapy.

Sleep feels like an addiction to me because . I crave it several times a day and am looking forward to how I can sneak it in. . I don't seem to be able to control it with will power for very long. . If I have a successful period, I seem to always eventually slip back into it. . I only have short periods when this isn't a problem. . When I am under stress it is at it's worse. . If I have any free or unstructured time, I can't control how much I sleep excessively. . When my time is heavily scheduled, I really struggle with keeping a full schedule and crave the time off when I can sleep for hours. . If I know I'll have a few hours in between activities free, I will find ways to sneak in some sleep. . I am embarrassed about this, don't tell the people around me the extent of the problems and devise ways to sneak in sleep without people knowing. . If I am anxious, I use sleep as a way to reboot my system, calm myself down or get another perspective. . After I have chosen excessive sleep over being up, I struggle with self-recriminations about how much of my life I have wasted, how I didn't accomplish the things I wanted, why it was not good for me, how most of my day was gone, etc.

The upside is my addition only hurts me.

For me, sleep addiction (and perhaps food addiction for others) are different than gambling, alcohol, smoking, drugs. Sleep is something you must do each day to live. I have no problem with total abstinence of things that aren't good for me (like drugs, etc). However, I really struggle day after day with getting up out of sleep.

I have researched this and I have not found any studies on "sleep addiction". However, in medical sleep science journals and among a few psychiatric journals there are recent studies on "delayed sleep phase syndrome" and "non- 24 hour sleep phase syndrome", whereby people who appear to sleep excessively simply have a malfunction of how melantonin is secreted in the system (perhaps due to the recent advent of the electric lightbulb) and do not sleep when most humans sleep. Studies are showing that a much larger percentage of the population unknowingly struggle with this disorder in isolation all their lives. This is turning out to be the be the biggest sleep disorder affecting the most number of people, even above insomnia and apnea. This is very little understood and has only been discovered and documented in science journals since 1981. DSPS is a recognized disability in the government disability system.

It seems that there is a huge gulf between the studies and expertise of medical sleep science and that of psychology/psychiatric studies on the sleep difficulties and the use of excessive sleep as a psychological coping mechanism.

# Answer
> 1 votes
According to Dr Piotr Wozniak, no.

### Oversleeping

To summarize what Dr Wozniak says, people need sleep to **optimize memory**. While there is an evolutionary benefit to overeating (conserving fat for the future), there is **none to oversleeping**.

Sleepiness is a combination of

1. a circadian component (the hours you usually sleep)
2. a homeostatic component (e.g. staying awake too long, learning too much).

What causes oversleeping is people who often sleep while they are tired before their bedtime, and the circadian component launches hormones that keep you asleep.

For example, if your usual bedtime is about 10 PM, your usual wake time is around 4-6 AM, which is when the circadian sleepiness wears off. If you are extremely tired and fall asleep at 6 PM, your circadian sleepiness hormones kick in at about 10 PM, leaving you sleepy until around 4-6 AM. You will fall asleep for about 12 hours and feel like you've slept for only 6, which is what many people interpret as oversleeping.

If you happen to sleep at 4 PM that day and sleep off the homeostatic component, you'll lack enough 'sleepiness' to fall asleep when the circadian part kicks in, and you'll get insomnia.

Thus, early sleepers will either get insomnia or oversleep, depending on how different from their usual circadian rhythm it is. Eventually, people's circadian rhythm will adjust to the new cycle, but people who keep adjusting their cycles and travel often (e.g. 2 AM one week, 6 PM the next) will often face oversleeping issues.

### Can sleep become addictive?

I'm no expert on how addiction works, so someone should correct me on this if mistaken.

Addiction is a habitual psychological or physiological dependence on a practice that is beyond voluntary control. Quite often, it occurs when you have a reward at the end of a cue.

E.g. someone starts drinking or smoking when they get stressed out. As they repeat this, they gain a psychological addiction to drinking or smoking every time they are stressed. The reward of nicotine/alcohol triggers and enforces the habit loop. After enough of the substance in the system, they become physiologically addicted to alcohol or nicotine.

Or someone begins gambling every time they are bored and have money in their pocket. The reward of getting money enforces a habit loop, creating psychological addiction. The cue of being bored and having money triggers the addiction, the reward of getting money enforces it.

Being unable to retrieve these rewards creates craving and thus, psychological addiction.

However, with sleep is difficult to do as a reaction to anything. One can easily overeat as a response to stress, but one cannot easily sleep as a response to stress.

There's little euphoria associated to sleeping; when you wake up, you'd normally feel a little drowsy instead of 'satisfied'. While someone lacking sleep can have a craving for sleep, it's difficult to form a habit loop of sleeping as a reaction to anything.

So, I'd argue that while very rare circumstances would make one addicted to sleep, it'd have to be a deliberately developed habit. The most likely case would be a craving to sleep whenever one opens a textbook. A 'craving' to sleep at night is quite normal, much like the 'craving' to eat several times a day caused by low blood sugar levels.

---
Tags: sleep, addiction
---


title: Why do humans like being touched?

text:
# Question
Title: Why do humans like being touched?
Why do people like to be touched so much, why would it make sense from a evolutionary perspective.

I know people enjoy hugs and company of opposite sex, but even people from the same sex hug and touch each other.

I wonder how this behavior could have evolved. Was it the struggle to keep warm that drawn people physically together? Does it all have to do with mating?

Maybe there just isn't enough data to specify how this behavior started out?

# Answer
Of all the senses, touch is the one that most connects a person to the external environment. When two people touch each other (a handshake, a hug, a kiss, etc.) a connection/bond is made. This bonding is deeply involved with social development and emotional interaction.

Interpersonal relationships are essential for social interactions. It is important to known where the boundaries are in your culture, so that personal space is respected. This varies widely between cultures and persons.
> 2 votes

---
Tags: social-psychology, developmental-psychology, evolution
---


# Question
Title: What does the literature suggest about the optimal strategy for quickly memorizing various types of content?
I just finished reading *Moonwalking with Einstein*, a journalistic piece on the World Memory Championships. The book explicates the various techniques used by participants to memorize different types of contest materials-- for example, there are techniques for memorizing large lists of numbers, foreign language vocabulary, packs of cards, and poetry.

The Dominic System, for example, is often used for memorizing numbers, the PAO system is often used for memorizing for packs of cards, etc.

However, a lot of these techniques have not been rigorously tested in a scientific setting to determine which forms of techniques are empirically optimal. Often, they're just circulated in underground communities, without any objective way to adjudicate between the merits of competing systems.

I was wondering what the research on memory suggests is the best way to memorize the above types of content. I suppose you need a metric to qualify "the best way", so let's say that preference is given to speed over duration of memory. I'm in the process of learning a new language, so I'm also particularly interested in foreign language techniques.

# Answer
The first and most obvious answer would be that repetition cements new information into memory. The second technique is that an event that involves a strong emotion will be more easily remembered then an event where little or no emotion is felt. If you are learning foreign languages, you could practice sentences or paragraphs in a dramatic way, like learning the lines of a play. This could be done verbally or non-verbally, but verbally would be preferred for the auditory feedback. Flashcards, mind maps, and similar tools would help with visual feedback, helpful as this article suggests. Handwriting and typing would help with tactile feedback.
> 1 votes

---
Tags: memory
---


# Question
Title: Can we draw conclusions about content of thoughts from neural firing patterns?
Can the neural firing patterns of animals be associated with specific kinds of thoughts? (ie Thoughts related to food, mating, or neighborly aggression?)

I am curious about the speculations in yesterday's Neuroskpetic blog post, "What is My Cat Thinking" on Discover Magazine's site. The author ponders if measuring his cat's neural firing patterns upon confronting a neighbor's cat, and then observing if similar patterns appear at other times when the neighbor's cat is not present, can be used as evidence for his cat's "thinking" or memory of the other cat.

The author concludes, preemptively, that such an experiment would not demonstrate anything about the content of thought: "We have no idea how neural firing relates to consciousness in humans, let alone animals."

However, I am quite sure I have seen various papers published that use fMRI and neural patterns as evidence of particular states of mind. There are also social science experiments in which participants' brains are electrically stimulated, resulting in particular actions (grabbing of a pencil, for example), and then asked to explain the motivations for this action. These experiments would suggest that it is already assumed that specific brain patterns correlate to specific thoughts and actions.

I am wondering to what extent biologists have already studied neural firing in relation to consciousness and the content of thoughts. More specifically, can we infer the recall of specific memories from a neural firing pattern?

# Answer
This is a complicated and loaded question. As Neuroskeptic noted, our understanding of consciousness is very poor (in fact, we don't know how to define it most of the time). To see some of the best current definitions, take a look at:

What are current neuronal explanations and models of 'consciousness'?

We definitely can't infer arbitrary properties of consciousness from something like fMRI. In general, we don't have a clear mapping from brain to mind, and thus all studies are inherently correlational in nature. Since all the work is correlational, it is thus not usually mentioned and the popular press tends to misconstrue this as a for-sure causal connection. But does that mean we can't infer any thoughts? No!

We can "read thoughts" well enough to produce an brain-computer interface. Adapted from my earlier answer:

Erik Ramsey is locked-in syndrome patient and is incapable of movement apart from his eyes. However, he has control of his brain enough to be distinguished by electrodes implanted into his cerebral cortex (Guenther, 2009). Although the sensors were implanted in the motor-area responsible for speech (which you would expect typical inviduals to have control over, since they can speak), the understanding of how to decode this is not full. Thus, the patient had to train in order to adapt to the system:

> Accuracy of the volunteer's vowel productions with the synthesizer improved quickly with practice, with a 25% improvement in average hit rate (from 45% to 70%) and 46% decrease in average endpoint error from the first to the last block of a three-vowel task.

In a much more dramatic experiment, Adrian Owen has used brain imaging techniques as means of communicating with vegetative-state patients. It is known that visualizing playing-tennis and walking around the house produce very distinct (to an fMRI) activation in the brain. So Owen used that capability to allow a vegetative-state patient to answer yes-or-no questions. He asked the patient to imagine playing tennis for yes, navigating the house for no (Monti et al., 2010). Hence, neuroscientists think they can distinguish the thought of walking around the house versus playing tennis.

Of course, it is hard to say if this can be continued arbitrarily far, in practice or even in theory. For more info, see this question:

Is performance reducible to brain activity in an unambiguous way?

### References

Guenther, F.H., Brumberg, J.S., Wright, E.J., Nieto-Castanon, A., Tourville, J.A., Panko, M., Law, R., Siebert, S.A., Bartels, J.L., Andreasen, D.S., Ehirim, P., Mao, H., & Kennedy, P.R. (2009). A wireless brain-machine interface for real-time speech synthesis. PLoS ONE, 4(12)

Monti MM, Vanhaudenhuyse A, Coleman MR, Boly M, Pickard JD, Tshibanda L, Owen AM, & Laureys S. (2010). Willful modulation of brain activity in disorders of consciousness. New England Journal of Medicine, 362(7):579-89.
> 8 votes

---
Tags: memory, consciousness, theoretical-neuroscience, neuroimaging
---


# Question
Title: How to tell a diagnosis from an actual state?
Since diagnoses merely represent what a doctor is thinking, how can a mental patient know the difference between de facto "reality" and what decisions a doctor is planning?

We know planning is not real but a mental patient can't say that a decision from a doctor is not reality, even though a decision from a doctor is not anything that has a physical existence.

So if the doctor decides a 5150 or likewise, I'm not asking about the legal processes but how you could convince that a diagnosis is not just a model.

What is a mutual indicator for every sz or psychosis? IF there is no common indicator, how can it be a diagnosis or a condition? What is absolutely impossible with e.g. schizophrenia that is possible with no schizophrenia?

Since paranoid schizophrenia could be just a person who is worried, which doesn't exclude anything does it.

# Answer
Doctors are trained not to diagnose a patient subjectively, but to use objective criteria. Psychologists and psychiatrists worldwide have agreed on a set of criteria, by which each doctor should arrive at the same diagnosis, if faced with the same patient.

The current practice is that all mental disorders are defined by a list of symptoms. If a patient shows a certain minimum number of symptoms from this list (no matter, which), it is assumed that he is very probably suffering from that disorder. A sample can be found under the section "Criteria" in the Wikipedia article on Schizophrenia.

This is the currenty way to diagnose a mental disorder, because, despite all its weaknesses (see the section "Criticsm" in the DSM Wikipedia article for an overview), it is believed to be the best of all bad methods (akin to Churchill on democracy) and no replacement has yet been found (unless you count Antipsychiatry as helpful in dealing with mental problems).

The lists of criteria and the minimum number of symptoms are given in the Diagnostic and Statistical Manual of Mental Disorders (currently DSM-IV-TR) and the International Statistical Classification of Diseases and Related Health Problems (currently ICD-10).

As you can conclude from this, a mental disorder is not a reality. It is a construct that consists of a collection of possible symptoms. The "actual state", as you call it, the physiological reality, is not accessible to the psychologist or psychiatrist.
> 10 votes

---
Tags: abnormal-psychology, cognitive-modeling, psychiatry, schizophrenia, psychosis
---


# Question
Title: Are cortisol measures more reliable than self-reported fear measures for looking at difference scores?
I was sent an email by a researcher with the following question:

> You wrote that difference scores are okay to use if measurement error is minimised.
>
> * Does that imply that biological data are more reliable for statistically analysing change than say a self-report personality scale?
> * For example, I've measured fear via cortisol and also self-report scale, does this mean that I can look at hormone measurements in a difference score but not on the self-report scales?

# Answer
I think the relevant reliability would be the expected test-retest reliability of the measure at the two time points which are otherwise being used to examine difference scores. Thus, if you were looking at difference scores derived from an experiment where measures are taken one day apart where an intervention is applied on one of those days, then you would want to know the correlation between those two days in the absence of any intervention.

In general, I would question your assumption that hormone measures are more reliable than self-report personality measures. I'm not experienced with hormone reliability data, but a good personality scale should have test-retest reliability around .80 or 90. My intuition is that hormone measures have much lower reliability than this, but I'd be very interested in anyone who can cite test-retest reliability measures for various hormone measures.

I found this discussion of cortisol test-retest reliability (Nicolson):

> Test-retest reliability of acute stress response measures appears to be low, probably because of both the underestimated noise introduced by spontaneous pulsatile activity (Young, Abelson, & Lightman, 2004) and the tendency of the cortisol response to habituate following repeated exposures. Low reliability of cortisol outcome measures means that laboratory stress experiments are particularly vulnerable to Type 2 error. This issue is important in all studies, but especially needs to be taken into account in intervention studies, where stress reactivity is compared pre- and postintervention. More analyses are needed to determine how many cortisol measures per session and how many repeated sessions are necessary to obtain reliable measures of stress reactivity for different subject populations and stressors (Gunnar & Talge, 2007; Hruschka et al., 2005).

### References
> 1 votes

---
Tags: measurement, emotion, statistics
---


# Question
Title: Images on personal computers - Which aspect of size to keep constant?
For various reasons we're doing a reaction time study involving images that runs on unstandardized equipment: patients' personal computers (unless they don't meet certain requirements).
It's not about vision or individual differences, but group-level intraindividual change in reaction times (attention retraining), so it's not *that* important that participants all have the same experience as long as it's not confounded with the experimental condition.

Most reaction time studies run on standardised equipment, with a standardised distance from the monitor etc.

We can at most ask participants to keep a certain distance to the screen, but we can't ask them to buy new monitors of course.

So, three basic options arise (assuming our images are in a sufficiently high resolution):

1. Use constant number of pixels.
**Positive**: We can use the same images for everyone, if we use a medium number of pixels, we can accomodate most resolutions. Also, potentially everyone sees the same amount of information (i.e. no information lost due to down-scaling).
**Negative**: With high resolutions, images may look pretty small, and with large monitors, participants may usually position themselves further away from the monitor habitually, so some see "less information".
2. Use constant display size (i.e. 7 cm wide).
**Positive**: On large and small monitors with different resolutions, images are the same size.
**Negative**: Apparently the information used to compute actual display size can be unreliable, so we may end up with different display sizes. We'll probably need different images and people with larger monitors and higher resolutions will be able to see more details.
3. Use constant fraction of display (i.e. 70% percent wide).
**Positive**: Fraction of display may do the best job of letting people perceive considering that people probably sit further away from bigger monitors.
**Negative**: Need images in different sizes (dynamically computed with JS). They may see different levels of detail.

These options could be combined (i.e. constant pixels unless that is less than 50% of the monitor) and there's also the option of letting users zoom (will result in somewhat blurry images though).

Is there any research into this matter and if not, which option sounds best perception-wise?

# Answer
> 3 votes
I don't think that (2) works. The physical size of the screen is not available to you. You may be able to calculate the dimensions in pixels, but pixel density (dpi), pixel format and sampling pattern change from screen to screen. So you won't be able to calculate the centimeters from the pixels.

I would do what web designers have done for centuries: **rely on the user to resize content to their needs**.

I would provide images in high resolution, display them at an initial size\* that works well on the most common screen resolutions (1366 x 768 and 1024 x 768), and provide a highly visible request to resize the image to make viewing comfortable. With Javascript you can offer fluid, continuous resizing options easily (e.g. TwinHelix or, what I prefer, YUI), allowing the users to resize web content in the same way they would resize the browser window. Or you can offer a number of preset sizes (+/- 10% etc.) and link these to different style sheets.

\*A good measure for the initial size, in my opinion, is the em. You can rely on two factors with this: if the user uses the computer at its factory settings, then type size is adapted to the screen size; if the user changed the settings, then type size is adapted to his visual ability and preferences. If you give image size in em, i.e. in relation to type size, images will be scaled to the users needs.

This is, of course, no exact science, but that is what I do, when I design a website. It is the closest I manage to get to cross computer similarity in size. As soon as you read about cross browser web design, you'll lose all optimism that your goals at exactness can be achieved ;-)

---

# Answer
> 1 votes
2 sounds reasonable. The variability you introduce by sticking to pixels or display ratios seems like it outweighs the apparent unreliability of monitor size calculations.

Also, unlike TVs that scale the content to fit the size, most webpages do not scale -- so, when I drag a webpage from my laptop screen to my second (larger) monitor, the size stays constant. Therefore, I would predict that people do not end up sitting as far back from large screens as you might expect. Therefore, the subtended visual angle will be approximately the same if the image is the same size for everyone.

# Answer
> 1 votes
If I managed to understand, each participant may have a slightly different viewing experience, as long as it's constant through multiple sessions each participant has.

To achieve this, you may ask participants to sit an arm's reach from their monitor. Try to make the images span the same physical size (even though it's really hard to achieve programatically). This way, the viewing angle would be relatively constant between participants, but more importantly, would be constant for each participant.

If the experiment is dependent to the level of details they can see on the pictures, you might want to consider low-res, and large-detailed images, to eliminate the advantage of those with better monitors.

Moreover, make sure they all use desktop computers, as many might want to user their tablet computers, or even their smartphones...

---
Tags: vision, software, internet, reaction-time
---


title: Practical Use For a Neuroimager

text:
# Question
Title: Practical Use For a Neuroimager
You may be aware that neuro-imagers have become much cheaper and many are available with a SDK. I think this will open up a huge gateway for much more intimate human interfaces. However, I am stumped at the practical uses and whether the human controlled interfaces will be much better to the user. A mind controlled TV remote (for hospital patients) came as an idea, but once again, I don't think it has much practical use. Could any point me to any practical uses of this device? I am sorry if I am posting in the wrong section or this is a very opened-ended question. Thanks for any input.

# Answer
In the context of this question, neuroimager refers to a commercial grade EEG/EMG device. For example the emotiv epoch (considered a high end of what is commercially available) had 3 or 6 electrodes. The output of these electrodes is available to a developer through a software interface created by the manufacturer.

I believe that Jsn is seeking ideas of what can be done using this technology. I have completed a small iPhone app for another commercial grade EEG device - there is way too many artifacts from motion, muscle activity and poor device placement.

Practically speaking, it's a fun "toy" to play with, and it is very mobile, compared to a hundred electrode arrays.
> 2 votes

---
Tags: neuroscience, computational-modeling
---


# Question
Title: Any research on how we use visual category information in visuomotor tasks?
So I've been reading up on the Two-streams Hypothesis\*, and it bothers me that the explanations both sides give only extend to tasks involving *one* type of visual information. For example, an experiment might require subjects to identify the category of an object (ventral stream) or correctly grasp an object (dorsal stream).

But surely there are tasks in the real world that require both sorts of information simultaneously...

For example, suppose I'm out picking apples: I want to put the ripe apples in my basket and knock the rotten apples to the ground. The ripeness categorization would presumably be a ventral task, whereas the action (grasping/knocking down) relies on dorsal information.

**Has there been any work on what mechanisms are behind our ability to perform such tasks?**

The closest I've come to an answer is this paper about we use rules to select actions, but the actions discussed don't involve the spatial properties of the rule defining object.

\*Brief summary of my understanding of the Two-streams Hypothesis: it posits two separate pathways in the brain for processing visual objects: a dorsal pathway for spatial and affordance information, and a ventral pathway for property and category information.

# Answer
From personal observation, the consensus seems to be that the two streams hypothesis is an oversimplification of the truth, albeit a useful one.

The primary reason that this hypothesis is seen as an oversimplification is because there is a lot of cross-talk between the two streams. For example, Zanon et al. (2010) provides evidence for functional connectivity using EEG and TMS. Himmelbach & Karnath (2005) provide evidence from neuropsychological patients with optic ataxia.

More direct evidence comes from Borra et al. (2008) and Felleman & Van Essen (1991), who provide evidence for cross-talk between streams in monkeys by tracing cortical connections.

Mahon et al. (2007) adresses your specific question, stating:

> In the course of manipulating and using objects, it is necessary to integrate the output of object recognition processes (ventral stream) with information about object motion (left middle temporal gyrus) and the motor commands necessary to realize the function of the objects (left inferior parietal lobule). The efficacy of such an information processing network would be increased if the organization of object recognition processes already anticipated the processing requirements of computations implemented ‘downstream.’ **(see article for more details)**

There have also been a few updated reviews of the two streams hypothesis, such as Milner & Goodale (2008), that might clear up some misconceptions.

Another oversimplification is that the functions of each stream are not entirely unique, as is often stated. For instance, areas in both the dorsal and the ventral stream contain neurons which respond to shape encoding (Lehky & Sereno, 2006), despite that this is generally considered a 'ventral' task.

Unfortunately the misconception that these two streams function completely independent of each other, and perform completely independent functions, is still being perpetuated in text books and journal articles.

# References

> Zanon, M., Busan, P., Monti, F., Pizzolato, G., & Battaglini, P. P. (2010). Cortical connections between dorsal and ventral visual streams in humans: evidence by TMS/EEG co-registration. Brain topography, 22(4), 307-317.
>
> Himmelbach, M., & Karnath, H. O. (2005). Dorsal and ventral stream interaction: contributions from optic ataxia. Journal of Cognitive Neuroscience, 17(4), 632-640. PDF
>
> Borra, E., Belmalih, A., Calzavara, R., Gerbella, M., Murata, A., Rozzi, S., & Luppino, G. (2008). Cortical connections of the macaque anterior intraparietal (AIP) area. Cerebral Cortex, 18(5), 1094-1111.
>
> Felleman, D. J., & Van Essen, D. C. (1991). Distributed hierarchical processing in the primate cerebral cortex. Cerebral cortex, 1(1), 1-47.
>
> Mahon, B. Z., Milleville, S. C., Negri, G. A., Rumiati, R. I., Caramazza, A., & Martin, A. (2007). Action-related properties shape object representations in the ventral stream. Neuron, 55(3), 507-520. PDF
>
> Milner, A. D., & Goodale, M. A. (2008). Two visual systems re-viewed. Neuropsychologia, 46(3), 774-785. PDF
>
> Lehky, S. R., & Sereno, A. B. (2007). Comparison of shape encoding in primate dorsal and ventral visual pathways. Journal of neurophysiology, 97(1), 307-319. PDF
> 6 votes

---
Tags: cognitive-psychology, perception, cognitive-modeling, vision
---


# Question
Title: Is there a learning style that involves learning best by teaching others?
**Background**: I'm familiar with the more common learning styles of hearing, seeing and doing. For lack of a better word I consider myself a 'vicarious' learner which is something similar to a Bodhisattva from Buddhism only without the enlightenment part. I learn best by helping other people learn it, or through explaining it successfully to someone else. Case in point algebra never made a lick of sense to me as a kid until I was able to get my mom to understand it (she's not math minded in the least).

**Questions:**

* Is there a term for someone who learns best by helping others learn?
* Are there only the three theoretical learning styles at present?

# Answer
> 6 votes
### Learning Styles

There is a large literature on learning styles particularly in educational psychology. See for example, the wikipedia page on learning styles.

You will soon discover that there are many different taxonomies of learning styles. Thus, there are certainly more than three "theorised" learning styles.

However, more importantly, there have been some serious critiques of the assumptions of learning styles. In particular, I would question whether people really have important domain general learning styles, and whether pedagogy should be adapted to such a domain general learning style.

I agree that instruction should be tailored to the individual. However, I think that generally it is more effective to consider what the individual already knows (and in some cases, think about their motivations) and tailor the format with regards to pre-existing knowledge and skills.

Furthermore, I think it is generally more useful to think about what makes for effective learning in general, as opposed to thinking about how people learn in different ways.

### Learning by teaching

In the case, of learning by teaching, I imagine that this could be a relatively effective learning methodology in general. From personal experience, I know that I learn a lot about a subject by teaching it. It forces you to understand the material. Students can ask you questions which forces you to learn more. Consideration of how to teach the material can encourage a deeper understanding in order to provide a structured teaching experience. The mere fact of spending time on a subject should also foster further learning.

I imagine there are many articles on the topic of learning through teaching. I found one article by Cortese (2005) who wrote:

> The great learning potential inherent in teaching would appear to be generated as the result of a particular aspect of the teaching process itself: the encounter with diversity, which on the one hand tends to increase reﬂexivity while on the other hand tends to break down resistance to change. ... Teaching also proved to be an important opportunity for recognizing one’s own ignorance and thereby rendering oneself open to the possibility of learning.

### References

* Cortese, C. G. (2005). Learning through teaching. Management Learning, 36(1), 87-115. PDF

# Answer
> 3 votes
I personally like Michelene Chi's taxonomy of instructional methods, which is related to your question although it's not specifically about learning styles. Chi distinguishes passive, active, constructive, and interactive learning activities. Passive means you're just receiving info from the instructor (or textbook, or whatever). Active means you're doing something in response to the info, e.g. highlighting. Constructive means you are MAKING something NEW in response to the info, e.g. you are writing an evaluation or commentary on what you read or heard. Interactive means you are talking with someone else about it, e.g. explaining it or asking questions about it. Each includes the previous one, i.e. constructive learning activities include active activities as part of them, interactive is a type of instructive, etc. Chi argues that the best learning occurs from interactive, followed by constructive, then active, and last passive.

Thus, to answer the original question, according to Chi it is generally true that you will learn best when you explain things to others - that should be true of everyone, not only people with a certain learning style.

> Chi (2009) Active-Constructive-Interactive: A Conceptual Framework for Differentiating Learning Activities. Trends in Cognitive Science.

---
Tags: learning, educational-psychology
---


# Question
Title: Does cognitive training enhance dopamine release?
Joe Hardy reports on a study by Backman et al (2011) in Science, where from the authors report:

> Updating of working memory has been associated with striato-frontal brain regions and phasic dopaminergic neurotransmission. We assessed raclopride binding to striatal dopamine (DA) D2 receptors during a letter-updating task and a control condition before and after 5 weeks of updating training. Results showed that updating affected DA activity before training and that training further increased striatal DA release during updating. These findings highlight the pivotal role of transient neural processes associated with D2 receptor activity in working memory.

Joe Hardy goes on to claim:

> This result shows that cognitive training with exercises similar to those on Lumosity can change the way the brain works at a fundamental chemical level. Indeed, we’ve known for several years that the right kind of cognitive training can enhance brain functions like working memory.

### Question

* Is it true that cognitive training enhances dopamine release ?
* Are there any studies that disprove this ?

### References

* Backman, L., Nyberg, L., Soveri, A., Johansson, J., Andersson, M., Dahlin, E., Neely, A.S., Virta, J., Laine, M. & Rinne, J.O. (2011). Effects of working-memory training on striatal dopamine release. Science, 333, 718.

# Answer
> 6 votes
The paper claims that training on updating (based on the influential view of executive function proposed by Miyake et al., 2000) tasks, which require maintaining and manipulating information in WM in response to new input or feedback, transfers to other memory tasks such as letter-memory and n-back, and that this transfer is associated with changes in phasic dopamine activity.

Hardy is therefore stretching the study conclusions quite far here. As Tyler Langan notes in his comment to the question, the effect of a neurotransmitter is enormously dependent on a number of factors beyond the type of transmitter, such as exactly *where* it is released, and for *how long* it is released, among others. In some sufficiently broad sense, it is probably true that "cognitive training leads to enhanced dopamine release," but I don't necessarily think that is meaningful in any explanatory sense.

When interpreting fMRI studies, it is always important to consider very, very carefully the exact relationship between the evidence and the claim, *especially* when venturing beyond the careful boundaries set down by the original authors. Consider, for instance, the carefully bounded conclusion reached by the original authors:

> Our data are consistent with findings of displacement of ligand binding to D2 receptors during cognitive processing (5, 8) and indicate a link between previously observed increases of BOLD activity after WM training (1) and DA release.

Contrast with Hardy's more free-style take on the matter:

> This result shows that cognitive training with exercises similar to those on Lumosity can change the way the brain works at a fundamental chemical level.

That's not technically incorrect, at least not as such, but it is disingenuous. In the particular sense his claim is "*not incorrect,*" it is also "*not incorrect*" to say that virtually any other activity performed over a long enough time-span (e.g. five weeks) "*can change the way the brain works at a fundamental chemical level*." Changing at the chemical level is a part of how the brain works, and what the study by Backman et al. illustrates is a *specific way* it changes under certain conditions.

**References**

> Miyake, A., Friedman, N. P., Emerson, M. J., Witzki, A. H., Howerter, A., & Wager, T. D. (2000). The unity and diversity of executive functions and their contributions to complex “Frontal Lobe” tasks: a latent variable analysis. Cognitive Psychology, 41(1), 49–100. doi:10.1006/cogp.1999.0734
>
> (link to pdf)

---
Tags: neuroscience, training, brain-training
---


# Question
Title: Does an exceptional working memory inhibit intelligence?
According to the Fox News article "Chimps Smarter Than Humans in Memory Test" chimps were able to significantly outperform humans in a simple working memory task. I quote one part of the article in particular:

> Matsuzawa speculated there was an evolutionary tradeoff between this kind of sharp memory and the higher mental functions seen in humans, such as our advanced capability for language.

Could this "trade-off" mean that training to improve working memory could cause your brain to adapt to such training at the expense of language and problem solving abilities?

Matsuzawa's 2012 article in Current Biology

# Answer
> 9 votes
No. Different parts of the brain are responsible for different functions, and the brain would not spontaneously reorganize based only on a improved WM.

Memory is a huge factor in intelligence, and improving WM would likely result in increased scores on intelligent tests, and in general is a good thing.

References:

Increased prefrontal and parietal activity after training of working memory

# Answer
> 12 votes
The conclusions drawn in Inoue & Matsuzawa's (2007) study, which seems to be available here, are suspect. First off, the sample sizes (6 chimp, 9 human subjects) are simply too small to draw good inferences about working memory, at least about human working memory, but as I imagine chimps are somewhat expensive subjects, c'est la vie.

Secondly, and more worryingly, the study design itself seems to have a real problem: Matsuzawa does not reveal how many hours of practice either group of subjects have had, but presumably, the humans have not had any practice, while it is explicitly noted that the chimps have had some. The mother-offspring pairs practiced the numerals task from offspring age 4, and then the block task from offspring age 5. Even if we ignore the sample size problems and take the reported results at face value, we are still left with a situation where the mother chimp Ai underperformed the humans, who in turn underperformed the offspring chimp Ayumu--also suggestive of a training effect.

This strikes me as a problem for Matsuzawa's claim, because we know that the ultimate limit of task-specific human memory span is very high compared to a task-general baseline. For instance, Ericsson, Chase and Faloon (1980) reported a case study of a subject who increased their memory span from 7 to 79 in 230 hours of practice, and one need look no further than the world memory records to see that the lack of control for practice seriously undermines Matsuzawa's claim about this unexpected "relationship" between chimp and human WMC.

A more restrained interpretation of the evidence presented in the article would suggest that sufficiently well-trained chimps can outperform untrained humans on the particular task. Any conjecturing about "evolutionary trade-offs" on the basis of these findings seem unwarranted to me, but that would have been the case even if these results had been ironclad.

### References

* Ericsson, K. A., Chase, W. G., & Faloon, S. (1980). Acquisition of a memory skill. Science, 208(4448), 1181–1182. doi:10.1126/science.7375930
* Inoue, S., & Matsuzawa, T. (2007). Working memory of numerals in chimpanzees. Current Biology, 17(23), R1004-R1005.

# Answer
> 9 votes
High working memory is associated with greater ability to learn meanings of abstract symbols, such as is required to do mathematics. I would be highly skeptical of a claim that there is a trade-off between WM and general intelligence.

> Ian M. Lyons, Sian L. Beilock, Beyond quantity: Individual differences in working memory and the ordinal understanding of numerical symbols, Cognition, Volume 113, Issue 2, November 2009, Pages 189-204, ISSN 0010-0277, 10.1016/j.cognition.2009.08.003.

Under some circumstances, high WM seems to be associated with poor problem solving under pressure, but not with poor problem solving in general.

> From poor performance to success under stress: Working memory, strategy selection, and mathematical problem solving under pressure. Beilock, Sian L.; DeCaro, Marci S. Journal of Experimental Psychology: Learning, Memory, and Cognition, Vol 33(6), Nov 2007, 983-998. doi: 10.1037/0278-7393.33.6.983

# Answer
> 3 votes
It looks like there is a developmental relationship between WM and general IQ:

Fry, A. F., & Hale, S. (1996). Processing speed, working memory, and fluid intelligence: Evidence for a developmental cascade. Psychological science, 7(4), 237-241.

Cole, M. W., Yarkoni, T., Repovš, G., Anticevic, A., & Braver, T. S. (2012). Global Connectivity of Prefrontal Cortex Predicts Cognitive Control and Intelligence. The Journal of Neuroscience, 32(26), 8988-8999.

# Answer
> 3 votes
The answer hinges on the definition of working memory. If we look at synthetics (people with synesthesia who have impressive massive visual memory correlations to time, numbers, etc) definitely **not**. They are worse in mathematics and stimulation will trigger unrelated memories. Synthetics with obsessive compulsive disorder that obsess about their personal memories are constantly cataloging everything they do.

On the other hand, the information-processing models by which we define intelligence hinge on the information storage capacities of working memory. Sufferers of ADHD show a 10 point drop in IQ because they are unable to persist towards more abstract goals, like learning multiplication tables, and get distracted. This is also what happens in older adults and women hitting menopause (Barkely, Adult ADHD).

---
Tags: intelligence, evolution, animal-cognition, working-memory
---


# Question
Title: Devices that detect when someone is falling asleep
I'm wondering what types of devices exist that can detect how close someone is to falling asleep. I have heard of several devices that may be able to do this, but I haven't been able to find very solid information.

* EEG: I assume these could detect falling asleep quite effectively; though, I'd like to know if there are any other devices that would work as well.
* EKG/ECG: I found this paper that claims you can use a Lorenz plot to detect correlation between heartrate and falling asleep.
* GSR: A lot of people say a GSR can be used, but I have yet to find any papers/data that describe the correlation between GSR and falling asleep
* Pulse Oximeter: someone mentioned to me that these work as well, though I haven't been able to find much information

# Answer
> 5 votes
The gold standard of sleep studies is polysomnography- using multiple sensors together to score sleep stages. It's very expensive and requires a lab. A night in a sleep lab costs about 3000$, last time I checked.

Actigraphy is a cheaper way of monitoring sleep by looking at the users motion. When 19 out of 20 minutes are scored as "no activity", the first minute of the 20 minutes sequence is classified as sleep onset. such Actigraphy algorithms that detect sleep onset latency have to 87% accuracy compared with polysomnography, and at very low cost. Chances are your iPhone or android device can be used as an Actigraphy to detect sleep onset. I wrote one such app for android and 2 for iPhone. Zeo is similar, although it works also by detecting motion related artifacts due to sleep stages, maybe as much as real brain waves.

# Answer
> 7 votes
I've used the Zeo (http://www.myzeo.com/sleep/). It seems to work pretty well. It tracks which stage of sleep you are using a very basic EEG. There are some details on how it operates here: http://radar.oreilly.com/2009/10/how-the-zeo-sleep-device-works.html

As I said, I've used it in the past and from what I can tell, it seems to be pretty accurate, assuming you don't knock the sensor off while you're sleeping.

---
Tags: sleep, eeg, devices
---


# Question
Title: What is the study which shows that babies can teach young children empathy?
I saw a fascinating segment on the PBS NewsHour which said that studies have shown that young children (ages 5 - 8 years of age) can be taught empathy by having a class where they observe and learn to care for an infant. The segment stated that this study showed the children would experience increased attention in class and a decreased likelihood that they would bully other children.

However, the report did not mention the actual name of the study. I'd like to read it to get further information. What is the study which shows that babies can teach young children empathy?

# Answer
I found the actual report on the PBS NewsHour. The program which teaches children empathy using infants is known as Roots of Empathy. It's Wikipedia article states:

> The Roots of Empathy program effectiveness has been evaluated nine different times by independent reviewers. Overall, the results were positive. The results showed that students who participated in the demonstrated several qualities including an increase in social knowledge, a decrease in aggression, an increase in sharing/inclusive/helping behavior, and an increase in emotional perception. These effects appeared to be lasting.

It does not, however, name these nine different reviews. It *does* name three publications:

> * *Roots of Empathy: Changing the World Child* by Child Gordon, Mary. Toronto: Thomas Allen, 2005.
> * *Family Literacy in Canada: Profile of Effective Practices*, Edited by Adele Thomas. Chapter: "Parenting and Family Literacy Centres of the Toronto District School Board" by Mary Gordon, editions Soleil publishing inc., 1998.
> * *Child Honoring: How to Turn This World Around*, Edited by Raffi Cavoukian, Sharna Olfman. Chapter: "The Power of Empathy" by Mary Gordon, Homeland Press, 2006.

On the Roots of Empathy website I was able to find a PDF Report on Research, which states:

> Researchers at the University of British Columbia have taken a lead role in early evaluations of ROE, under the direction of Dr. Kimberly SchonertReichl. Starting in 2000, the team conducted several studies across different grades and populations

and it also mentions eight "Research outcome evaluations to date":

> * UBC 2000-2001 Primary Grade Evalution,1-3
> * HCMO 2001-2004 Randomized Controlled Trial
> * UBC 2001-2002 National Evaluation
> * UBC 2002-2003 Rural/Urban Evaluation
> * UBC 2003-2004 Randomized Controlled Trial
> * UA 2006 Whole Schools Project
> * UA 2006 Grade One Project
> * UBC 2008 Fifth and Sixth Grade Evaluation

But does not provide actual links to the methods, data and results of those evaluations. I *was* able to find one of them: searching Google for "HCMO 2001-2004 Randomized Controlled Trial" yielded Effectiveness of School-Based Violence Prevention for children and Youth (Robert G. Santos, Mariette J. Chartier, Jeanne C. Whalen, Dan Chateau, Leanne Boyd) which appars to be one of the studies I was seeking.

I would still welcome a complete list with links, but I expect I might not be able to get that, the articles might be behind paywalls.
> 11 votes

---
Tags: reference-request, educational-psychology
---


# Question
Title: How long can a person stay happy, excited and motivated about something new?
I'm interested in learning more about studies or experiments that determine how long a typical person can stay excited about something new:

```
New job
new project
new relationship
new idea
new purchase/toy

```

Is there any evidence to support the hypothesis that humans are excited by new things/prospects, but only for a short time? If so, how short? Is it days, weeks or a "honey moon"?

A while ago I've heard a talk on TED.com that happy people are up to 30% more productive (Does happiness affect productivity?), and I'm wondering if this is applicable to "being excited about something new" - **i.e: are people more effective/smart when they are taking on new project, new job or a new relationship?** Are people more excited, energized and engaged **when they conceive new ideas?**

It would also help if I get to learn what the search term for "being excited about something new" is.

Update: Looking into happiness and productivity produced two terms: "Happiness economics" and Hedonic Adaptation. The article on hedonic adaptation says that happiness is homeostatic in nature

> a system that regulates its internal environment and tends to maintain a stable, relatively constant condition of \[its\] properties

Reading that happiness regulates itself (as in negative feedback) sounds very reasonable to me, and I recall reading about antidepressants and Serotonin, which also mentioned that Serotonin production uses negative feedback, where more Serotonin released now inhibits release of more Serotonin, thus antidepressants dont work immediately and require a couple weeks to take effect\[looking for a link\].

**I'm wondering if the process of being excited about something new is also homeostatic in nature?**

# Answer
Probably the most striking evidence of "happiness homeostasis" is a now classic study by Brickman, Coates and Bulman (1978) which compared the self-reported happiness of lottery winners and accident victims with a control group. The following quote describes the part of the outcome you'd be interested in succinctly:

> Lottery winners and controls were not significantly different in their ratings of how happy they were now, how happy they were before winning (or, for controls, how happy they were 6 months ago), and how happy they expected to be in a couple of years.

Except for one, the lottery winners were between one and 18 months removed from their winnings, while the group of accident victims were one to 12 months removed from their accident. This seems to indicate that yes, happiness is broadly speaking a homeostatic process (but as with most homeostatic processes, it's likely complex).

That's probably not the precision level you were looking for, but there's quite a literature--almost 1600 citations on Scholar for this paper alone. One other limitation of it is that it uses interviews instead of ecological momentary assessment, which a more modern paper would likely want to employ. That might be another term to keep in mind.

**References**

> Brickman, P., Coates, D., Janoff-Bulman, R. (1978). Lottery winners and accident victims: Is happiness relative?. Journal of personality and social psychology, 36(8), 917-927.
> 12 votes

---
Tags: emotion, performance, motivation, ideation
---


# Question
Title: What is the effect of not sub-vocalizing on reading comprehension?
Sometimes when reading, text segments are not so important or relevant, when that happens I tend to read between lines in a visual manner, without sub-vocalizing or pronouncing the words in my mind.

Could that way of reading affect text comprehension?

# Answer
> 6 votes
Yes, inhibiting sub-vocalization is likely to impair comprehension.

Here is the abstract from Slowiaczek & Clifton (1980):

> Two experiments demonstrated that subvocalization is of value in reading for certain types of meaning. Blocking subvocalization by requiring subjects to count or say “cola-colacola …” aloud impaired their reading comprehension but generally not their listening comprehension. The effect of blocking subvocalization was found to be specific to tests that required integration of concepts within or across sentences, as contrasted with tests that required only memory of individual word concepts. Two hypotheses were offered: first, that subvocalization results in a more durable memory representation needed for integration of concepts; and second, that subvocalization enables a prosodic restructuring that makes information needed for sentence comprehension accessible.

# Reference

> Slowiaczek, M. L., & Clifton Jr, C. (1980). Subvocalization and reading for meaning. Journal of Verbal Learning and Verbal Behavior, 19(5), 573-582.

---
Tags: reading
---


# Question
Title: Why does speaking with rhythm help a subject get into a trance?
Various hypnotism teachers tell you to speak with a relaxed voice with rhythm. You can see Derren Brown on this in The Experiment - The Assassin (from 4:48 to 5:40):

> Soft, rhythmical language, repeated phrases ...

Also here, in a paper from Robin Allott:

> A number of elements in successful oratory can be identified. Oratory uses some of the techniques also found in poetry: sound patterns (assonance, alliteration, repetition); strongly marked rhythmic patterns.

Why does rhythm help getting the subject in a trance?

# Answer
> 6 votes
This is not exactly my area, but I suspect it simply may not be anyone's area.

It is not clear from the research literature that speaking rhythmically does help get into a trance, mostly because it is not currently clear that "trance" is distinct from other forms of dissociation (though dissociation is often confusingly described as "trance-like" or variations thereof). The closest recent paper I could find (Becker-Blease, 2004), simply reports on subjectively reported associations between certain kinds of music and the experience of a "trance" state, but this does not answer the questions of why or whether speaking rhythmically induces dissociative states.

A non-paywalled review of dissociation and dissociative states in a clinical context can be found in a Review of Psychiatry chapter by Putnam, 1991. Putnam employs the following definition of dissociation:

> Dissociation is a process that produces a discernible alteration in a person's thoughts, feelings or actions so that for a period of time certain information is not associated or integrated with other information as it normally or logically would be.

Unfortunately, while subsequent literature in the same line of research has tentatively described a difference between clinical and nonclinical dissociative experiences (Waller, Putnam and Carlson, 1996), this was only descriptive, and did not attempt to investigate ways of inducing dissociative states. The focus appears to have remained on clinical dissociation.

In conclusion, the literature and evidence currently does not seem to distinguish between the two possibilities that nonclinical dissociation either can or cannot be induced by rhythmic speech, and there does not seem to be any meaningful consensus or even particularly influential views on the cognitive processes underlying nonclinical dissociation. It simply does not seem to be an active area of psychological research.

# References

> Becker-Blease, K. A. (2004). Dissociative states through new age and electronic trance music. Journal of trauma & dissociation, 5(2), 89-100.
>
> Putnam, F. W. (1991). Dissociative phenomena. Review of psychiatry, 10, 145-160.
>
> Waller, N., Putnam, F. W., & Carlson, E. B. (1996). Types of dissociation and dissociative types: A taxometric analysis of dissociative experiences. Psychological Methods, 1(3), 300.

---
Tags: experimental-psychology
---


# Question
Title: At what point do multiple personas for social context cross into multiple personalities disorder?
Recently I took part in a conversation about the difference between the "many hats" of a successful corporate executive, and "multiple personality disorder." Although humorously bantered, the ideas shared in that conversation shed a light on the fuzziness between when consistent multiplicity of personality characteristics is useful and good (to better adapt to a variety of environments), and when is it counter-productive or self-defeating, and labeled multiple personality disorder? What are the "cross-over" points?

Multi-tasking in executive management positions require being able to speak in the vernacular of many stake holders and to be able to communicate effectively with a wide variety of groups and collaborators. Corporate cultures vary between industries, countries, even regions, and size of the enterprise, etcetera, and yet, a successful corporate executive can walk in any of these with ease. **How can the effective use of these "chameleon expressions" be distinguished from split personality?**

I use this example tongue in cheek, but Mitt Romney is the perfect example of someone whose personalities clashed in company with one another (fund raiser, 47% vs. 100%). He is a very successful businessman, did his changing faces in the media unravel a persona that didn't really exist?

# Answer
> 8 votes
I think the difference comes down to awareness and control. A person who "wears many hats" and can step into different archetypes is a sort of personality chameleon, whereas a person with dissociative identity disorder has little or no control over changing personalities, and certain personalities within that person may be only partially or completely unaware of other personalities.

# Answer
> 5 votes
The *cardinal diagnostic trait* of "multiple personalities," or dissociative identity disorder (DID), is dissociative states. Following Putnam (1991), dissociation can be defined as follows:

> Dissociation is a process that produces a discernible alteration in a person's thoughts, feelings or actions so that for a period of time certain information is not associated or integrated with other information as it normally or logically would be.

At first glance, executives and DID patients do both engage in multiple roles, to some extent. However, executives' coordinated, strategic utilization of multiple roles strongly imply that their roles exist in an integrated, interdependent form, rather than the disorganized form that characterizes DID patients. This means we have every reason to think the executives are not dissociated, and that the relationship is therefore likely spurious (something which seems plausible at a glance, but which is essentially a coincidence).

---
Tags: social-psychology, abnormal-psychology
---


# Question
Title: How can I use gamification to encourage people to complete workplace training?
I am looking for ways to improve the likelihood people will perform mundane but required workplace training. I am looking into gamification techniques.

My organisation requires that employees complete short online learning courses (think Health and Safety, Security Awareness, Risk Management, Company culture). We often find it a struggle to ensure everyone completes the required courses on schedule.

Admittedly the courses themselves can be a little dry. I can't change that yet. However I want to find some ways to improve the rate at which people complete the tasks.

I am familiar with gamification techniques and concepts.

* What specific techniques and concepts of gamification might work in increasing training compliance?
* what do I need to keep in mind when implementing them?

# Answer
> 6 votes
For applied purposes, gamification can be captured within a self-determination theoretical framework. Self-Determination Theory (SDT) is an influential theory of motivation which grew out of research on intrinsic/extrinsic rewards in the 1970's, and which has been applied to virtually every learning setting. The main proponents of SDT include Edward Deci and Richard Ryan, who in and of themselves have a lot of publications you may want to sift through.

# Self-Determination Theory

SDT holds that people become motivated to engage in work based on three properties: autonomy, competence and relatedness. Autonomy refers to a desire to experience feelings of individual freedom in how and when to perform the task; Competence refers to a desire to experience feelings of control and mastery from performing a task; Relatedness refers to a desire to experience feelings of connection to others from performing the task.

Further, SDT also makes a distinction between intrinsic and extrinsic motivation (Ryan and Deci, 2000). In more complex settings, this distinction becomes extremely important. However, for the purpose of encouraging participation in "mundane, required workplace training," it is likely not necessary to consider intrinsic motivation. An analysis of the degree to which any external rewards employed in implemented gamification techniques may reduce intrinsic motivation to engage in mundane workplace training seems to me like shooting birds with cannonballs.

# Evaluating Gamification

Following Aparacio et al. (2000), gamification techniques can be evaluated in terms of their motivational autonomy, competence and relatedness properties. A brief summary of their recommendations for evaluating gamification techniques follows.

> 1. Identify the main objective.
> 2. Identify one or more underlying objectives that are interesting to people.
> 3. Select game mechanics that match the objectives and support autonomy, competence and relation.
> 4. Analysis of the effectiveness gamification based on fun, quality indicators, satisfaction, and service quality.

# References

> Aparicio, A. F., Vela, F. L. G., Sánchez, J. L. G., & Montes, J. L. I. (2012, October). Analysis and application of gamification. In Proceedings of the 13th International Conference on Interacción Persona-Ordenador (p. 17). ACM.
>
> Ryan, R. M., & Deci, E. L. (2000). Intrinsic and extrinsic motivations: Classic definitions and new directions. Contemporary educational psychology, 25(1), 54-67.

---
Tags: learning, io-psychology, motivation, training, gamification
---


# Question
Title: Term for incentives working without conscious awareness
Is there a term that captures the idea that **incentives work** even when people deny their choices have been swayed by them?

For example, an individual amazon book reviewer may deny that a recent improvement in their rankings caused them to spend 10 minutes writing a review instead of 5. They may be honest that they weren't consciously aware of the connection in a single act. But statistically it might (by some well-controlled experiment) be evident there is likely a causative correlation, over time, over many participants.

Or changing scoring models on StackExchange might change behavior more than explainable by conscious decision.

Or a crowded store gets better sales due to social influences.

Of course perverse incentives and competing incentives (social, financial) will complicate, but I want a term to capture the concept that incentives influence choice to a degree **more than the participants are aware**.

So I'm not asking for argument how much or little this works, but for a well-accepted term for it.

# Answer
> 7 votes
Annoyingly, it depends what area of the research literature you happen to find yourself in. In the perception literature, the distinction lies between **subliminal and supraliminal**. In the memory and learning literature, the distinction lies between **implicit and explicit**. In dual-process decision-making theories, the distinction lies between **automatic and controlled**. The former terms broadly refer to "unconscious processing" while the latter terms refer to "conscious processing," but I wouldn't say unconscious/conscious is a well-defined distinction.

There is some general cross-overlap, but of these three distinctions and areas, the distinction that sees the most use in the other two areas would have to be explicit/implicit. They differ mostly in what stage of the process in the mind the researcher is interested in: perception, memory or thought. There is, to my knowledge, unfortunately no term which broadly captures all unconscious processing from input to output AND maps to the literature.

If you want the term to map to the literature, I think you'll have to commit to one or another. If it's for a lay audience, "implicit X" is fine, where X is whatever you think best fits the intended meaning.

---
Tags: terminology, motivation, unconscious
---


title: Memorizing sets of items

text:
# Question
Title: Memorizing sets of items
It is often useful to memorize a set of items. Many times ordering is not important and we need to memorize a lot of sets. I already know a method for memorizing lists where we memorize an item for each number and then create crazy associations between the new items and our memorized list of items. This method is not so good when we want to memorize e.g.

```
DivisionA = { John, Robert, Alex, Arnold, Sarah }
DivisionB = { another 5 names }
DivisionC = { another 5 names }
...
DivisionX = { another 5 names }

```

This is only a possible example. The sets can change during time, so the memory technique should be flexible. There are a lot of real life examples where is it useful to memorize a set, e.g. a doctor could learn a set of side effects of certain drug. A historian could learn family members of certain king. A movie-expert would like to remember filmography of certain director. There are a lot of such examples when people desire to remember higher number of sets.

Another technique that I don't find much smart is suggested here as converting the set to the list and then memorizing the successors of individual items with spaced repetition. Though, converting to some kind of ordering or association with something else seems to be unavoidable. The bad part is actually the pure memorization.

The disadvantage of the method of loci is that we have to memorize many locations (prepare them in advance) before we can store items to discrete places in that locations. Maybe this technique could be improved in some way.

Which memory techniques are appropriate for this task? It should have long time retention, good recall, be dynamic (sets can change a little during time).

# Answer
The literature generally provides strong support for the use of **self-testing** in cases like this, particularly via the use of flash cards (Karpicke and Roediger, 2008). The efficacy of self-testing for facilitating learning of arbitrary or complex sets of items has been suggested to be driven largely by the combination of two effects: the **generation effect** (Slamecka and Graf, 1978) captures the tendency for active retrieval of memory (e.g. fill-in-the-blank) information to increase the probability of successful future recall, as well as the **spacing effect** (Donovan and Radosevich, 1999), which captures the tendency for learning at a moderate intensity over time to outperform learning all at once.

# References

> Donovan, J. J., & Radosevich, D. J. (1999). A meta-analytic review of the distribution of practice effect: Now you see it, now you don't. Journal of Applied Psychology, 84, 795-805.
>
> Karpicke, J. D., & Roediger, H. L. (2008). The critical importance of retrieval for learning. Science, 319(5865), 966–968. doi:10.1126/science.1152408
>
> Slamecka, N. J., & Graf, P. (1978). The generation effect: Delineation of a phenomenon. Journal of experimental Psychology: Human learning and Memory, 4(6), 592-604.
> 5 votes

# Answer
Look up Memory Palaces. I taught my girlfriend all the a-typical antipsychotic drugs in about an hour (there were 10 or something. I don't remember.) It was her first time doing it and she still remembers the whole list, in order, 6 months later. Using that "palace," she can add all the drug side effects to each medication by filling the room she placed her item in.

The memory palace technique is perfect for people in science and medicine. For memorizing poetry word for word, I chunk a few words together and memorize the most significant word. It's much easier than filling a memory palace with a ton of words. You can also use this to receit speeches.

If you want a fun, quick read on this, dive into Moonwalking with Einstein.

It's a skill that takes practice and serious effort. And yes, memorizing a few Shakespeare poems has come in handy. Being asked unexpectedly if I brought a poem to a poetry reading, hands empty, was probably the smoothest moment of my life. It's like in Anchorman when Ron plays the jazz flute, except you can bring your jazz flute anywhere.

You'll always be entertained, too, if you memorize some good stuff. Just remember it again and you can experience it anywhere. When you're climbing uphill after a long bike ride, it's like you can turn on the TV.

Edit: Also good to learn memory techniques so you can remember all your map directions and not have to keep checking your phone to go somewhere new.

Double edit: Don't be discouraged by the hour figure. Any normal guy can remember a deck of cards in order after having 10 minutes to memorize it. It just takes practice and a diary to monitor your skill and become an expert.

Daniel Temmet, the math savant, went from normal to incredible by practicing memorization.

And if you memorize by route, just reading and re-reading until you get it in your head long enough to pass a test, you're doing it wrong.
> -4 votes

---
Tags: memory, long-term-memory
---


# Question
Title: What is it called when a student tends to speak about what he knows?
Sometimes, a student who has a lack of knowledge, tries to change the topic of a question so that it will be about what he knows and can speak about. Is this a known phenomenon in psychology?

# Answer
> 3 votes
Tom Boardman's suggestion in the question comments about the Law of the Instrument ("if all you've got is a hammer, everything looks like a nail") seems to capture an important aspect of this, especially with respect to illustrating that it's not necessarily done out of malice.

The simplest theoretical explanation would cast this in terms of **top-down processing and attention** (Ward, 2008), combined with the **availability heuristic** (Schwarz et al., 1991). These two factors lead to a situation where whatever a student is knowledgeable about is more likely to come to mind in a discussion, and then whatever is on the student's mind is incorporated into the discussion. When the student encounters something that doesn't fit into what they know well, they might inadvertently change the subject to something that does, simply because that's what comes to mind and thus ends up being what shapes their thoughts.

**References**

> Lawrence M. Ward (2008) Attention. Scholarpedia, 3(10):1538.
>
> Schwarz, N., Bless, H., Strack, F., Klumpp, G., Rittenauer-Schatka, H., & Simons, A. (1991). Ease of retrieval as information: Another look at the availability heuristic. Journal of Personality and Social psychology, 61(2), 195-202.

---
Tags: terminology, educational-psychology
---


# Question
Title: Do ability tests predict maximal more than typical job performance?
I have often read that ability tests are indicative of what people "can do", but that job performance also depends on what people "will do".

For example, Ackerman and Beier (2012) wrote that:

> There is a fundamental mismatch between what is measured by extant intelligence tests and the criteria one is most interested in, when predicting job-related performance measures, that is, the mismatch between typical and maximal behaviors. ... Although assessments of what someone can do will serve as an assessment of the upper bound of a person’s performance on the day that the applicant is assessed, I–O psychologists and managers are most interested in what the applicant will do on a day-to-day basis on the job—that is, the individual’s typical performance.

Thus, my questions are:

* What is the correlation between maximal job performance and typical job performance?
* To what extent do ability tests predict maximal performance more than typical performance?

I'm interested in learning about empirical studies that have tested these ideas. I also imagine that findings will vary based on factors related to the work setting, and so forth (e.g., some work environments permit greater variability in discretionary effort). Also, presumably the degree to which ability-performance correlations differ between typical and maximal will be greater where the correlation between typical and maximal is lower. I'm also interested in understanding more about the methodological challenges associated with operationalising typical and maximal performance.

### References

* Ackerman, P. L., Beier, M. (2012) The problem is in the defition: g and intelligence in I-O psychology. Industrial and Organizational Psychology, 5 149–188.

# Answer
The distinction between maximum and typical performance was originally established by Sackett et al. (1988), and since then, how to predict either and their relation to one another seems to have been a very active area of research. In fact, there is a prohibitively large literature on the matter for a full review.

Fortunately, your questions were recently addressed comprehensively, along with other inquiries about the relationship between typical and maximum performance, in the December 2007 issue of Human Performance. To start, one paper by Barnes and Morgeson (2007) which provides support for Ackerman and Beier's claim, in its descriptive sense, that typical performance is that which is of interest to employers, which found that compensation was predicted by typical performance and intra-individual performance variability, but not by maximum performance. I suspect the claim was made in a prescriptive sense, though, so let's continue and see where the evidence takes us.

In the same issue, Marcus et al. (2007) reported support for the long-standing claims that measures of cognitive ability, such as g, serve as predictors of maximum performance, whereas measures of personality serve as predictors of typical performance. Tables provided in this paper also suggest, to me, that a meaningful correlation between typical and maximum performance may be tricky or impossible to elicit, as does another paper in the same issue of the journal.

This paper, by Mangos et al. (2007), suggests that job performance in an ecologically valid setting tends to be characterized by a mixture of need for typical and maximum performance, which I think makes life somewhat difficult for Ackerman and Beier's claim about what IO psychologists and managers are interested in, in the prescriptive sense, with respect to performance. **Methodologically**, it is not clear how we ought to dissociate the two, and **theoretically**, it is not clear why we would want to.

In conclusion, based on this special issue on the matter, it seems the simplest answer to your question about ability tests and maximum performance is that **ability test scores seem to account for a large amount of the observed variance**. With respect to your question about the correlation between maximum and typical performance, it unfortunately appears the answer to your question is **complex and not readily summarized**.

# References

> Barnes, C. M., & Morgeson, F. P. (2007). Typical performance, maximal performance, and performance variability: Expanding our understanding of how organizations value performance. Human Performance, 20(3), 259-274.
>
> Mangos, P. M., Steele-Johnson, D., LaHuis, D., & White III, E. D. (2007). A multiple-task measurement framework for assessing maximum-typical performance. Human Performance, 20(3), 241-258.
>
> Marcus, B., Goffin, R. D., Johnston, N. G., & Rothstein, M. G. (2007). Personality and cognitive ability as predictors of typical and maximum managerial performance. Human Performance, 20(3), 275-285.
>
> Sackett, P. R., Zedeck, S., & Fogli, L. (1988). Relations between measures of typical and maximum job performance. Journal of Applied Psychology, 73(3), 482.
> 3 votes

---
Tags: intelligence, io-psychology, performance
---


# Question
Title: What is the field that studies community responses to incentives?
Having recently read Freakonomics I was particularly interested by the idea of the responses of a community to incentives - as an example, the tale of a school which tried to introduce a financial penalty for picking up children late, which inadvertently had the opposite effect, as it nullified the previously existing (but largely invisible) social penalty.

Is there a general theory for this kind of interaction of incentives with community? If so, what is its name, and where could I read more about it? I'm interested in books and papers on a variety of levels, from popular accounts (à la Freakonomics) to textbooks to research papers.

# Answer
There is a specific field of economics that deals with the process of changing people's responses through incentives: Behavioural Economics.

> study the effects of social, cognitive and emotional factors on the economic decisions of individuals and institutions and the consequences for market prices, returns and the resource allocation.

A recent issue of The Economist covers some of the current approaches used by governments to change individual behaviour:

> Behavioural economists have found that all sorts of psychological or neurological biases cause people to make choices that seem contrary to their best interests. The idea of nudging is based on research that shows it is possible to steer people towards better decisions by presenting choices in different ways.

Some of the approaches, for instance used by the British Behavioural Insights Team, are merely ways of changing a message:

> The Nudge Unit has been running dozens of experiments and the early results have been promising\*. In one trial, a letter sent to non-payers of vehicle taxes was changed to use plainer English, along the line of “pay your tax or lose your car”. In some cases the letter was further personalised by including a photo of the car in question. The rewritten letter alone doubled the number of people paying the tax; the rewrite with the photo tripled it.

It's become a very fruitful area of research so would recommend taking your interest further.
> 4 votes

# Answer
I suspect economics is not the best framework for this because financial incentives are actually very limited in their efficacy in real-world contexts. The example in the question is a good demonstration: the financial incentive was a lot weaker than the social incentive it replaced. Applied Psychology might be a better place to look, in part because it requires a more or less explicit theory of decision-making and behavior change.
> 2 votes

# Answer
**Game Theory** has principles to contribute, such as the Nash Equilibrium.

> A set of strategies is a Nash equilibrium if each represents a best response to the other strategies. So, if all the players are playing the strategies in a Nash equilibrium, they have no unilateral incentive to deviate, since their strategy is the best they can do given what others are doing.

Change the incentives in a community, and it can be expected to migrate from one Nash Equilibrium to another. This would attempt to account for the knock-on or ripple effects, e.g. late pick-up fee makes parents less respectful of the teachers who have to stay late, and resentful teachers make students more cynical, etc.
> 2 votes

---
Tags: terminology, reference-request, social-psychology
---


# Question
Title: Do children follow parents' phobias genetically or by learning?
Children's personalities come from two sources: Parents' genes and the environment.

* Is there any research showing adults acquiring phobias as a result of being exposed to parents with the same phobia when they were a child?
* For example if an adult is afraid of height, darkness or water, does this increase the probability of having parents with the same phobia?

# Answer
> 4 votes
Yes, phobias appear to be partly hereditary. This encompasses both genetic and environmental factors.

Kendler et al. (1999) review some work in this area:

> We have previously reported, from a population-based sample of female twins, that the liability to agoraphobia, social phobia and animal phobia was modestly infuenced by genetic factors with heritabilities estimated between 30 and 40% (Kendler et al. 1992a). For situational and blood-injury phobia, by contrast, twin resemblance appeared to be due to familial environmental risk factors, which were responsible for ~30% of the variance in liability (Kendler et al. 1992a; Neale et al. 1994b).

A shortcoming of these studies is that they rely on single lifetime assessments, which may be unreliable. Kendler et al. (1999) tries to rectify this by following up with their original sample 8 years later. They conclude:

> Short-term reliability of the five phobias was modest (mean $\varkappa$=0.46), but higher than long- term stability (mean $\varkappa$=0.30). Unreliability occurred both for subject recall of unreasonable fears and for interviewer assessment of which fears constituted phobias. Examining fears and phobias together, in a multiple threshold model, results suggested that twin resemblance was due solely to genetic factors, with estimated total heritabilities, corrected for unreliability, of: any 43%, agoraphobia 67%, animal 47%, blood-injury 59%, situational 46% and social 51%.

They go on to compare their theory with other theories of phobia acquisition, such as classical conditioning and social learning theory. They state:

> By contrast, our results are supportive of an \`inherited phobia-proneness' model (Seligman, 1971; Gray, 1982)

This variance explained does, of course, leave considerable room for learned phobias. So, one should not overemphasize the hereditable components of fears and phobias (Delprato, 1980).

# References

> Delprato, D. J. (1980). Hereditary determinants of fears and phobias: A critical review. Behavior Therapy, 11(1), 79-103.
>
> Gray, J. A. (1982). The Neuropsychology of Anxiety. Oxford University Press: New York.
>
> Kendler, K. S., Karkowski, L. M., & Prescott, C. A. (1999). Fears and phobias: reliability and heritability. Psychological medicine, 29(3), 539-553. PDF
>
> Kendler, K. S., Neale, M. C., Kessler, R. C., Heath, A. C., & Eaves, L. J. (1992). The genetic epidemiology of phobias in women: the interrelationship of agoraphobia, social phobia, situational phobia, and simple phobia. Archives of General Psychiatry, 49(4), 273.
>
> Neale, M. C., Walters, E. E., Eaves, L. J., Kessler, R. C., Heath, A. C., & Kendler, K. S. (1994). Genetics of blood‐injury fears and phobias: A population‐based twin study. American journal of medical genetics, 54(4), 326-334. PDF
>
> Seligman, M. E. P. (1971). Phobias and preparedness. Behavior Therapy 2, 307-320

---
Tags: abnormal-psychology, developmental-psychology, genetics
---