text: TEL-T 347 Promotion & Marketing in Telecommunications Class Number 10968 5:45-7:00 MW This course will give the student an understanding and appreciation for marketing in telecommunications, including television, radio and the Internet. The class will touch on traditional marketing concepts (terms such as branding, reach, frequency, consumer research), and emerging new technologies, tactics and techniques. Since marketing is an evolving discipline, emphasis will be placed on current strategies and techniques employed throughout all media, with a concentration on television. Marketing is also a collaborative process, so class participation and a cooperative project will be part of your grade. Course Objectives: * To understand the purpose of marketing in electronic media; * To conceive, execute and evaluate marketing strategies and tactics; * To acquire knowledge of disciplines within marketing departments; * To increase awareness of marketing efforts of the media. Course Philosophy: "Marketing means solving customers' problems profitably." -- Randall Chapman, PhD (www.marketingprofs.com) * Marketing is cumulative. Your grade will be too. Rather than taking points off for mistakes, you will accumulate points for everything you do – attendance, class exercises, assignments and exams. * Marketing is a dialogue. This class will be too. * Marketing is not about one-size-fits-all solutions. We will look at how you know when to break with convention. * Marketing is about prioritizing and deciding what is the best solution for you. You will be forced to deal with the reality of small budgets, limited time and compromising the quality of your work. * Marketing is about responding to what is happening in the marketplace. We will be observing what is currently happening in electronic media and analyzing the thinking behind those choices. To see which requirements, in the College of Arts and Sciences, this course will fulfill consult the College Bulletin at http://www.indiana.edu/~bulletin/iub/college/2010-2011/. If you have questions, or need additional help, see your academic advisor.


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I would recommend using a regular computer or finding a browser for the PSP which can run chat.
In general, posting want ads for items has been discouraged in the forums. I'm not going to delete this yet due to the circumstances, but be aware that your post may be deleted at some point.
Searching for Boomstick
Talk about the game. What game? The game with the power? What power? The power of ... aw, skip it.
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Re: Searching for Boomstick
Leader of PFE league. If you wish to worship me, ask me about joining my secondary league Cult of Satan (the largest league in the game!).
Re: Searching for Boomstick
Yep, in general trades are a bad idea on the forums. It takes the most transient of actions and makes a permanent record, and is just bad data for anyone who stumbles on it later. The circumstances here are a little weird, and I don't have a good answer for that at the moment. I think the answer may be "if you want to trade, you'll have to find a device that supports chat" but that's not official yet. Until we've had some time to talk it over I'll leave the thread up, but it'll probably be locked/deleted at some point.
Genus, if you get your hands on a boomstick, please post so players know you're done looking.
Genus, if you get your hands on a boomstick, please post so players know you're done looking.
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Re: Searching for Boomstick
Can I suggest this: http://riptapparel.com/shirt/11/27/2010/my-boomstick
Navpane Rebuff: http://userscripts.org/scripts/show/87404
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Re: Searching for Boomstick
Just so you know, Boomsticks have been in high demand lately so you'll be lucky to find one for less than 2-3 stars (1m - 1.5m chips).
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(5) Customer Reviews
Price Range: USD $66.99 to $178.99
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OHTSU AT4000 ALL-TERRAIN offers an aggressive siped tread design with deep tread blocks enabling a bigger bite to grab the ground in all types of weather and surfaces. Available in many popular sizes, featuring raised white letters, or reversible to black, and a four groove aggressive block pattern results in excellent traction on and off highway. Ohtsu AT4000 offers all-season, all-terrain performance and durability to provide great daily service on highways, back roads or no roads.
Four grooves aggressive block pattern results in excellent traction on and off highway. Dynamic wave grooves provide excellent traction on various terrains. Phase-shifted, random pitch variation tread block helps reduce tire noise. Multi-sized blocks for improved traction. Tapered shoulder is effective for wandering resistance on the road. Full nylon cap ply plus belt edge improves structural integrity. Tough sidewall rubber for off-road protection. High tension polyester radial casing for off-road strength and highway uniformity. Two wide steel belts for high rigidity crown and solid off-road durability.
Great tires! They handle well on my full sized ford and have the same if not more bite on and off road as my previous Goodyear Wrangler Authority's. They do not do as well in mid as they are an all terrain tire but are great, especially for the price. Noise on road increased around 15,000 miles but still is a dull and quiet hum.
Size: 31x10.50R15
made this review on 12/11/2016 and is a
Confident, Experienced Driver
Size: 285/75R16
Vehicle: 1999 Dodge Ram 1500 4 Dr Crew Cab, 7 Ft Bed ST (225/75R16 106 S) with 32180 KM of Tire Wear
made this review on 6/13/2015 and is a
Confident, Experienced Driver
Have these tires under the falken high country name.
Tires have great initial attributes for traction, tread depth, and noise levels.
I currently have 43km on them and will be likely done by 50km
the phasing/droning sound has increased considerably along with the
Vibration levels.
I will look to a different tire as it feels like I just put this set on and nearly all the tread sipes have disappeared. Centre tread is nearly smooth and close to wear bars..
Size: 265/75R15
Vehicle: 2007 GMC Canyon 4 Dr Extended Cab 6 Ft Bed SLE (265/75R15) with 43000 KM of Tire Wear
made this review on 11/1/2014 and is a
Confident, Experienced Driver
Surprisingly quiet, good grip on dirt roads.
Sizing chosen is not stock, slightly thinner and higher.
Looks great on Tribute/Escape, handles well.
Size: 225/75R16
Vehicle: 2010 Mazda Tribute 4 Dr Sport Utility GX with 500 KM of Tire Wear
made this review on 5/23/2014 and is a
Aggressive Driver (Hard Cornering)
About 3000 miles so far only complaint is on cold days they take a set from being parked overnight, but round out within the first mile or so.
Very good traction in water and light snow and a very nice ride (low noise) on pavement. This tire is as good as BF Goodrich a/t and at
a substantially lower price point. I was pleasantly surprised at this tires
off road ability to climb and bite into soft sand and gravel. I would buy
these again.
Size: 275/65R20
Vehicle: 2002 Dodge Ram 1500 QuadCab 4wd (Ram 1500 QuadCab 4wd) with 3000 KM of Tire Wear
made this review on 8/30/2013 and is a
Confident, Experienced Driver
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Hello! My name is Jennifer and I am an educator in Texas. I have taught for the past 10 years and am currently taking time off to pursue my dreams as a consultant and curriculum designer. I currently work from home and travel around the United States (so far) to train teachers on interactive learning.
Between working from home, keeping up my blog and traveling I do stay quite busy. I have been on and off Pixel Scrapper for a few years and never really settled in until some fellow teachers brought it up to me a few weeks ago.
Thank you for an amazing place.


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Ukrainian parliamentarians host roundtable discussions about emerging security challenges
The European Integration Committee of the Verkhovna Rada of Ukraine jointly with the NATO Information and Documentation Centre in Ukraine initiated a roundtable discussion entitled Responding to Emerging Security Threats and Challenges in the 21st Century, which took place in the Ukrainian Parliament on 15 February 2012.
Members of parliament, state officials, representatives of NATO member and partner embassies, as well as military experts and representatives of the civil society, communicated via VTC with senior NATO officials in Brussels.
The Ukrainian audience listened to Dr Jamie Shea, NATO Deputy Assistant Secretary General for Emerging Security Challenges, speak aboutKey Challenges to Security in the 21st Century: A View from NATO. Ludwig Decamps, expert from the Defence Investment Division's Smart Defence Direct Support Team, explained NATO's Smart Defence initiative.
An evolving world means evolving security challenges
In his opening remarks, Ambassador Borys Tarasiuk, Chairman of the European Integration Committee, stressed that the emerging challenges of the 21st century bring new security issues. "The world radically evolves and so do the security challenges, which reflect hi-tech achievements," he noted.
Natalia Nemyliwska, Director of the NATO Information and Documentation Centre in Ukraine,echoed his remarks,saying that "The world is a changing place and the security landscape with it. Our globe is facing new challenges and threats not only centred around problems we are confronted with at home, but piracy, weapons of mass destruction, threats of terrorism, etc."
"We are living in a globalized and inter-connected world where problems in one particular region can have serious implications and consequences for all of us, even if we are not directly and immediately affected. And here, we cannot operate alone - partnerships are important," added Nemyliwska, while explaining the importance of international cooperation in the security sphere.
Balancing budgetary constraints and defence
The financial crisis presents another challenge for all countries. Even developed countries are sharply cutting defence costs, with more and more countries applying the NATO "smart defence" principle. Last year, the US reduced its defence budget by almost half a trillion dollars, whereas Russia, China and India are significantly increasing their military budgets.
Finding an optimal balance between streamlining defence budgets and upgrading the national armed forces can be difficult. While giving countries an opportunity to develop a competitive army and cut unnecessary costs, it is not an easy task stressed the speakers, including representatives of the Defence Ministry and the General Staff.
A valuable partnership
During a video link with NATO Headquarters in Brussels, Dr Shea said that the Alliance has plans for further cooperation with Ukraine, despite its declared non-aligned status. "NATO's partnership policy with Ukraine has not fundamentally changed – cooperation continues," he noted. "We need to develop more flexible approaches to partnerships based on common interests." The struggle against piracy, exchange of intelligence data, and cyber defence development represent a just a few areas where this could be applied.
"Playing out anti-piracy scenarios during joint US-Ukrainian 'Sea Breeze' exercises helps Ukraine and NATO member states to resist potential threats," pointed out Marcin Koziel, Director of the NATO Liaison Office in Ukraine.
Both Koziel and Shea emphasized the continuing operational value of NATO's Distinctive Partnership with Ukraine for international peacekeeping operations, where Ukrainian expertise and airlift capacity are great assets.


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Peavy trade talks collapse as the Cubs decide that the price is too much; Is DeRosa trade still possible?
The three teams trade, with a possible fourth team, that may have sent Jake Peavy over to the Cubs from the Padres, which would have involved the Phillies getting second baseman Mark DeRosa from the Cubs in exchange for young pitcher J.A. Happ and a second prospect, collapses, as the Cubs General Manager Jim Hendry informs the Padres General Manager Kevin Towers that his team has changed its mind about taking Peavy in exchange for several players that they would have needed to send over to the Padres, after making a trade with the Phillies, and with a possible fourth team. To be frank, while I don't know whether the trade would have help or hurt either the Cubs or the Padres, if it has gone through, receiving DeRosa may have helped the Phillies in the short turn, as they had someone ready to play second base as they waited for Chase Utley to come back from his post-season hip surgery, and then help the team by being involved in the team's platoon in left field afterwards, if the second prospect that the Phillies would have been sending to the Cubbies along with Happ, wasn't someone who may have made a major contribution to the team in the near future. But, if the second prospect was someone important to the Phils' overall future, it might end up being a usual major mistake by the club. Since the trade instead collapsed, we may never know for sure. As for the Phillies and the Cubs and DeRosa, the two teams might still do a straight up trade between themselves, if the Phillies are really interested in DeRosa, and the trade did not hurt the Phils' future. I guess we'll know in the next few weeks.


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Extra six months for escaped killer
A convicted child killer serving life in jail has been handed a further six-month sentence after escaping prison and going on the run.
Alan Giles, 56, absconded from an open part of HMP Hewell on October 28.
After a massive manhunt he was arrested by police in Alcester nine days later.
West Mercia Police said Giles admitted escaping from lawful custody and was sentenced today at Worcester Crown Court.
Giles, originally from the Oldbury area of the West Midlands, was given a 19-year tariff for the 1995 kidnap and murder of teenager Kevin Ricketts.
The 16-year-old's body was not found until 1998, after Giles asked to speak to detectives from West Midlands Police while serving his sentence.
Following his escape from HMP Hewell, a manhunt was launched with up to 50 officers working on the investigation at any time.
More than 100 potential sightings were received from members of the public, all of which were followed up, police said.
Officers closed in on Alcester after several sightings of the prisoner in that area on November 6.
He tried to run down an alley away from police but was arrested after two members of the Special Constabulary chased him.
Detective Inspector Stephen Tonks, of West Mercia Police, said: "During the nine days or so that Giles was missing there was a great deal of concern in the community, particularly in North Worcestershire where the prison is and in Warwickshire where most of the sightings were.
"We are extremely grateful to members of the public who rang in with sightings and for the hard work and commitment of the officers from West Mercia, Warwickshire and neighbouring forces.
"In particular, praise needs to go to the two officers who caught Giles and this case is an excellent example of the valued contribution that Specials make. An off-duty Police Community Support Officer who cycled in from home to join the search after a member of the public knocked on his door also deserves to be singled out for his dedication to duty."
Police said Giles, who had been living rough while on the run, would have been eligible for consideration for parole this year.


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By Mike Monroe
As Gary Neal arrived at his locker Saturday night after the Spurs' 121-117 victory over Denver, Danny Green, his next-door neighbor in the Spurs' team room, was pulling on his socks and shoes and checking a message on his cell phone.
"Danny Green," Neal said, "if I'd gone down to Austin for a couple of games, I might never have gotten back on the floor here again."
The two shared a laugh before Neal uttered a maxim every reserve player knows to be the truth: "It's all about opportunity."
Green on Saturday made the most of his latest chance to show he belongs, not just in the NBA, but in coach Gregg Popovich's plans for every Spurs game.
The third-year pro from North Carolina scored a career-high 24 points, exceeding his previous high by 11, to help the Spurs gain their sixth home-court win without a loss.
Making three of four shots from 3-point range, Green also threw in a variety of lay-ins off drives and pull-up shots, catching the Nuggets by surprise.
"He's an NBA player, and he's playing with confidence," Popovich said. "He's been through a lot of trials and been denied many times over the last several years. He's a great example of sticking with it and not getting down on one's self, continuing to play, improve, listen.
"Right now he's playing well and been a significant part of what we've done."
Denver coach George Karl, a fellow North Carolina Tar Heel who keeps in close touch with the basketball gang back in Chapel Hill, N.C., didn't expect Green's offensive explosion.
"The Carolina guys have always told me he's a glue guy and a winner," Karl said. "I always liked his intangibles, and it looks like his skills are getting to a big-time level, too. I'm happy for him."
Neal and Green have gotten their opportunity this week after the hand injury that has Manu Ginobili on the shelf for six weeks. Neal had been scheduled for a rehab assignment with the Austin Toros before Ginobili's injury.
Green's opportunity came when the Spurs needed a defender on Wednesday to slow down Golden State's Monta Ellis. That earned him more minutes.
"My teammates made the game real easy for me tonight," he said.
DUNCAN AS FACILITATOR: Spurs captain Tim Duncan played only 2:35 of a tense fourth quarter Saturday and was used mainly as a trigger man on in-bounds plays during crunch time. He also sat out the entire second period, during which the Spurs led by as many as 20 points.
"You don't plan for something like that ahead of time," Popovich said. "You play the game, and whatever the game dictates, that's what you try to do. Every one is different."
Duncan had a slick assist on the Spurs' final basket of the game, finding Tony Parker slicing to the bucket with 20.5 seconds left for a lay-in and a 119-111 lead.


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SANTA ANA – The 39-year marriage began blissfully.
But the ups and downs of the relationship took their toll on a Rancho Santa Margarita man who "exploded" the night "he struck his wife in a heat of passion" with a one-pound nightstand figurine, not realizing he was hitting her head, the man's attorney told an Orange County jury Wednesday.
Defense attorney Calvin Schneider said Richard Gustav Forsberg, 63, killed his wife Marcia Ann Forsberg, 60, in the early hours of Feb. 9, 2010, after the couple argued – but that it was not murder.
"He exploded when Mrs. Forsberg shuts him off" by dismissing her husband and turning away from him, Schneider said, telling the jury in Superior Court Judge William Froeberg's court that his client is guilty of voluntary manslaughter, not of murder.
After finding his wife had no pulse, Schneider said Forsberg wrapped her bloodied head in a towel, put her body in a bed sheet, placed her in an upstairs bathtub and put ice in it. He cleaned blood from the walls and the bedpost.
Deputy District Attorney Ebrahim Baytieh told the jurors what followed, events that Forsberg eventually described in police interviews months after the killing: He decapitated his wife, dismembered her body, kept her frozen parts in freezers he bought, rented an RV and then incinerated her body parts at a campground in Ventura County.
"He acted in the most gruesome and inhumane manner. He didn't want to be married anymore" to a woman who had suffered from cancer and other medical issues, the prosecutor told jurors in his opening statement. "She was murdered by a man who was supposed to protect her."
The childless couple had stopped having sex for a decade and Richard Forsberg frequented massage parlors to have sex with prostitutes, Baytieh said.
After the couple argued on the night of the killing, the defendant thought Marcia Forsberg went to sleep, the prosecutor said.
Then, "in the most cowardly way, he murdered her," he said.
"He didn't just murder his wife, he didn't just decapitate her, he didn't just dismember her, what he left of her is this," Baytieh said, showing jurors a blank overhead screen. "Nothing."
Richard Forsberg left nothing of her body because he did not want to be held accountable for the slaying, the prosecutor said.
Baytieh showed jurors a picture of the shiny aluminum walls of the inside of a freezer in which Forsberg is accused of stuffing his wife's body parts.
"This is as close to a coffin this murderer gave his wife of 39 years," he said.
Investigators did not find any remains of Marcia Forsberg after searching a fire pit at Lake Piru in Ventura County.
Her husband took her ashes and bones and threw them away, the District Attorney said.
Schneider, the defense attorney, said his client decided to cremate his wife, saying Richard Forsberg took some of her ashes and placed them on a tree in Ojai, where she grew up. The defendant talked with his wife and apologized to her when he dispersed her ashes, the lawyer said.
Prosecutors said Forsberg hit her in the head multiple times with the small statue on Feb. 9, 2010. He kept her body at home and decapitated and dismembered it over the next few days, they said.
Prosecutors said that he then rented an RV, bought two freezers and drove to Lake Piru to burn the body parts. When friends asked about Marcia Forsberg's whereabouts, the defendant told them they were having marital problems and she had left town to be on her own.
In August 2010 concerned friends reported the victim missing.
If convicted of one felony count of murder, Forsberg faces a maximum sentence of 25 years to life in state prison. If found guilty of the lesser voluntary manslaughter charge, he faces a maximum 11 years in prison.
When police checked on Marcia Forsberg's welfare Aug. 15, 2010, and later that month began asking her husband questions, the defendant checked into a spa hotel in Palm Springs and sent a confession letter to detectives before attempting suicide, prosecutors said.
"There's lots of feelings of dread … the jig is up … I'd rather kill myself than be caught," he told detectives in one interview.
Much of the evidence against the defendant comes from his own statements to police, Schneider said.
Baytieh played snippets from the hours-long interviews Orange County Sheriff's Department investigators conducted with the defendant.
In one taped scene, Forsberg clinically described how a bone saw caught his eye at a Huntington Beach hunting store and it was what he needed to saw a cold body.
"It is way difficult to cut through frozen bodies," Forsberg said. The bone saw was just the right tool, he said.
Was it gruesome to decapitate?
"I was surprised at how easy it was for the most part," Forsberg said. "She had been dead for more than 12 hours … conceptually, it was gruesome."
You did all the cutting at one time?
He did some on Feb. 9 and the rest the next day.
"I took the saw with me in the RV to make pieces smaller to put in the fire," Forsberg said.
Forsberg made hand sawing gestures for detectives and motioned with both his hands when describing the cuts he made: two for each arm, one for each foot, one for the head.
Contact the writer: 714-834-3773 or firstname.lastname@example.com


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This year is a landmark year for the RHS Chelsea Flower Show. Not only is it celebrating its centenary year, but the 100-year ban on garden gnomes has also been lifted! Gnomes were by no means the most unusual garden feature at this year's show, however, as innovative sculpture, unusual materials and unique aesthetics have been used to create some truly memorable displays.
Other gardens have a more sombre mood, however, with many raising awareness for charities such as Arthritis Research UK and Sentebale. Throughout the show the gardeners' incredible skill and dedication is abundantly clear, and will no doubt inspire visitors to make the most of their own green spaces at home.
Visitors who walk down Sloane Street on their way to the show this year will also notice two floral elephants on its east side, which were installed on Monday to raise awareness of Habitat for Humanity's Animal Ark initiative. This charity project, alongside many others, will have its own garden at the 2014 show.
As for so many great London institutions, the first 100 years really are only just the beginning!


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Let's Jam!
There are a lot of different ways to go electric. Let us help guide you!
Traveling with your Cello
Traveling with your instrument can be tricky, especially if you play cello. Read our tips.
A Silent Violin?
Aren't violins made to be heard? Why would you want a silent violin? We explore the advantages.


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Numerous ocular parameters have been proposed as reliable physiological markers of drowsiness. A device that measures many of these parameters and then combines them into a single metric (the Johns Drowsiness Scale [JDS]) is being used commercially to assess drowsiness in professional drivers. Here, we examine how these parameters reflect changes in drowsiness, and how they relate to objective and subjective indices of the drowsy state in a controlled laboratory setting.
A within subject prospective study.
29 healthy adults (18 males; mean age 23.3 ± 4.6 years; range 18-34 years)
Over the course of a 30-h extended wake vigil under constant routine (CR) conditions, participants were monitored using infrared reflectance oculography (Optalert) and completed bi-hourly neurobehavioral tests, including the Karolinska Sleepiness Scale (KSS) and Psychomotor Vigilance Task (PVT). Ocular-defined increases in drowsiness were evident with extended time awake and during the biological night for all ocular parameters; JDS being the most sensitive marker of drowsiness induced by sleep regulatory processes (p < 0.0001). In addition, the associations between JDS in the preceding 10-min period and subsequent PVT lapses and KSS were stronger (AUC 0.74/0.80, respectively) than any other ocular metric, such that PVT lapses, mean response time (RT), and KSS increased in a dose-response manner as a function of prior JDS score (p < 0.0001).
Ocular parameters captured by infrared reflectance oculography detected fluctuations in drowsiness due to time awake and during the biological night. The JDS outcome was the strongest predictor of drowsiness among those tested, and showed a clear association to objective and subjective measures of drowsiness. Our findings indicate this real-time objective drowsiness monitoring system is an effective tool for monitoring changes in alertness and performance along the alert-drowsy continuum in a controlled laboratory setting.
Anderson C; Chang AM; Sullivan JP; Ronda JM; Czeisler CA. Assessment of drowsiness based on ocular parameters detected by infrared reflectance oculography. J Clin Sleep Med 2013;9(9):907-920.
Drowsiness is an unstable, rapidly fluctuating state of reduced alertness along a sleep-wake continuum that can result in large variability in performance impairment over relatively short intervals of time. Despite efforts to manage drowsiness, it is often an inevitable consequence of modern society, such that drowsiness is a major contributory factor in ∼20% of motor vehicle crashes1–3 and poses a significant risk to occupational health and safety, especially for those engaged in shift work.4 The potential risk of occupational accident or injury due to drowsiness is largely determined by the fundamental properties that control alertness. These include (1) the number of hours awake5; (2) nightly sleep duration where repeated nights of inadequate sleep (sleep restriction) result in gradual decrements in alertness and performance6; (3) certain times of day characterized as high or low alertness due to activity of the intrinsic body clock7; (4) impairment of alertness soon after waking8; and (5) the presence of a sleep disorder.9 In order to quantify fluctuations in alertness and drowsiness due to these primary physiological factors, a wide number of neurocognitive and physiological measures have been employed.
Current Knowledge/Study Rationale: Ocular parameters are known to be sensitive to changes in drowsiness, yet current methods are time consuming, invasive, and require extensive offline processing. This study evaluates a non-invasive device based on infrared oculography to detect changes in drowsiness.
Study Impact: Our study provides support for a new approach to monitoring drowsiness in the laboratory environment. The findings presented here have implications for future studies which seek to evaluate changes in drowsiness using a non-invasive method, with minimal off-line processing, and clear thresholds for drowsiness.
Numerous measures shown to depict reliably the developing drowsy state include changes in human electroencephalographic (EEG) output,10,11 electrooculography (EOG) or other oculographic measurements,7,12,13 heart rate variability,14–16 and neurobehavioral measures of attention and vigilance (i.e., psychomotor vigilance task).6,17,18 While these measurements are sensitive to drowsiness, they can present numerous problems: (1) most measures require substantial off-line processing, especially EEG/EOG; (2) performance measures present a snapshot of performance decrement and are unable to provide a continuous marker of dynamic drowsiness; (3) many require quiet, sterile environments to reduced potential confounds from noise or distraction19; (4) no well-defined cutoff or threshold for impairment is available for many of these outputs; and (5) while EOG is typically recorded in laboratories, often with the sole purpose of capturing REMs for the purpose of scoring sleep, these do not capture the developing drowsy state but rather a sleep initiation state; and while laboratory-based EOG is capable of distinguishing a blink from a saccade or slow eye movement,7 it is not able to depict reliably the drowsy state beyond gross slow eye movements.
Eye blinks and eye movements ("oculometrics") are inextricably linked to central nervous system function and provide a unique window on general activity within the midbrain reticular formation, which is well known to play a central role in vigilance and attention.20 Various types of eye and eyelid movements have previously been associated with changes in the drowsy state, including: percentage or duration of eye closure,21–23 blink duration,12,22,24–27 blink rate12,28 or blink amplitude,29 pendular motions,30 slow eye movements,7,31 lid closing/reopening time,22,32,33 interval between blinks,34 changes in pupil size,35 saccadic velocities,36–38 and (more recently) amplitude-velocity ratios of the eye closure.32,33,39 While the study of ocular parameters to reflect a fluctuating state of alertness is not new,30,40 recent interest has intensified culminating in development of numerous drowsiness detection technologies,41 such as PERCLOS23 and Optalert.32,33 PERCLOS, a measure of the proportion of time the eyes are closed > 80%, has previously been shown to relate to changes in vigilance, as determined by the psychomotor vigilance task (PVT).16,42,43 While these systems have been developed to identify and warn of drowsiness in the field, they may provide a useful marker of drowsiness in the laboratory without the associated problems with many current approaches.
One of these commercially available drowsiness detection systems is of particular interest, as it enables several oculomotor parameters to be continually measured via noninvasive, infrared reflectance oculography (Optalert, Melbourne, Australia). A weighted combination of these ocular parameters provides a single, sensitive measure of dynamic alterations in drowsiness levels, the Johns Drowsiness Scale (JDS). The JDS is proposed to be a more sensitive marker of drowsiness and has previously been used to depict drowsy driving,32,33 vigilance and attention,32,33,44 changes in alertness following caffeine ingestion,45 and changes in EEG-defined drowsiness.46 Currently, no independent prospective study exists that examines the extent to which the ocular parameters detected by this system, including the JDS, reflect dynamic changes in alertness and drowsiness over time due to fluctuating levels of drowsiness associated with sleep regulatory processes (i.e., time awake and circadian phase). In addition, the extent to which ocular parameters detected by infrared reflectance oculography relates to established laboratory-based measures of drowsiness is unknown. Examining changes in ocular parameters via infrared reflectance oculography due to changes in sleep drive, and how these outcomes relate to existing laboratory-based objective and subjective measures of drowsiness forms the basis of our study.
Twenty-nine healthy participants (18 males; mean age 23.3 ± 4.6 years; range 18-34 years) were studied in the Center for Clinical Investigation of Brigham and Women's Hospital. The study was approved by the Partners Human Research Committee at Brigham and Women's Hospital, and subjects provided full written informed consent prior to study. All participants underwent comprehensive physical, psychological, and ophthalmological examinations prior to study and were free from any medical, psychiatric, or sleep disorder. Participants engaged in night and/or shift work in the previous 3 years, and those who traveled across more than 1 time zone in the prior 3 months were excluded from the study. For 3 weeks prior to study, participants were instructed to maintain a consistent, self-selected 16-h wake/8-h sleep schedule as confirmed by time- and date-stamped calls at bedtimes and wake times, in addition to actigraphy (Actiwatch-L, Minimitter, Inc, Bend, OR) 7-14 days prior to admission to the study. During this time, participants were asked to refrain from use of any prescription or non-prescription medication, supplements, recreational drugs, nicotine, caffeine, and alcohol. Compliance with this requirement was verified by urine and blood toxicology during screening and by urine toxicology prior to admission to the study.
The data described in this manuscript were part of a larger 8-day inpatient study protocol.47 Participants were studied for 8 days in an environment free of obvious time cues (no windows, clocks, radio, live TV, newspapers), and continually monitored by staff trained not to reveal the time of day. The protocol consisted of: (i) one baseline day/night (16:8 wake-sleep), followed by (ii) 5 days of timed light exposure designed to phase advance the sleep episode by 8 h while maintaining 8-h sleep episodes; followed by (iii) a 30-h constant routine and final 8-h recovery sleep episode. The 5-day phase advance segment of the protocol may have been 1 of 3 different timing regimes and 1 of 2 lighting conditions (this prior exposure had no effect on the data presented here-see results). Following the 5-day advance protocol, participants underwent a 30-h extended wake episode under constant routine conditions. During that time, participants were asked to remain awake in dim light (3 lux), in a semi-recumbent position (head of the bed at 45°), with the equivalent daily fluid and caloric intake provided in small hourly snacks. During the 30-h constant routine, participants were monitored with infrared reflectance oculography (Optalert) starting 1 h after waking on the CR (sleep inertia testing occurred post wake for 1 h). Infrared reflectance oculography was monitored continuously except during PVT tests when a head-mounted eye tracker was being used. Participants were instructed to remain looking ahead. See supplemental material for schematic example of study protocol.
The eye and eye lid movements were monitored using infrared reflectance oculography whereby IR transducers attached to the frame of a pair of special glasses/spectacles detects ocular movement (Optalert Drowsiness Measurement System, Sleep Diagnostics Pty Ltd, Melbourne, Australia; described in full elsewhere33). The system provides a measure of various components of eyelid movements during spontaneous blinks, measured each minute. These include: the mean duration of the eyelids remaining closed during blinks, the mean interval between the times of maximum closing and reopening velocities of the eyelids during blinks, the number of long eyelid closures per minute, the total % time of long eyelid closures per minute, the mean relative velocity of the eyelids closing during blinks (assessed by the amplitude/velocity ratio [AVR] of each such movement), and the mean and standard deviation of the relative velocity (AVRs) of the eyelids reopening during blinks.
Typically, an eye blink is approximately 300 msec in duration, which includes (i) the closing phase, (ii) full eye closure, and (iii) the reopening phase. These phases are used to calculate the various ocular outcomes. Ocular outcomes that were examined include:
Johns Drowsiness Score: A score between 1 and 10 (see above)
Negative amplitude-velocity ratio (AVR): the ratio between the maximum amplitude to the maximum velocity for the reopening phase of all eye blinks per minute epoch. A larger ratio indicates slower reopening of the eye.
Long eye closure: not including the closing phase and reopening phase of the eye during each blink, this metric examines the interval when the eye is completely shut (full closure). Here, a long eye closure is deemed to be > 10 msec. This measure reflects the percentage of time, per minute, that the eyes are deemed fully closed for > 10 msec.
Inter-event duration: not including the closing phase and reopening phase of the eye during each blink, the inter-event duration refers to the time between the maximum velocity of the eyelid closing to the maximum velocity of the eyelid reopening for the same blink. This is averaged over one minute.
Total blink duration: a measure of the total duration of an eye blink, including the duration of the closing phase, the closure, and the reopening phase of the eye blink.
Time with eyes closed: not including the closing phase and reopening phase of the eye during each blink, this metric examines the interval when the eye is completely shut (full closure). This metric reflects the percentage of time within a 1-min epoch when the eye is fully closed.
Participants rated their subjective sleepiness using the Karolinska Sleepiness Scale (KSS)48 every 30 min throughout the extended wake episode (30 h). This is a 9-point scale ranging from "extremely alert: 1" to "extremely sleepy, fighting sleep: 9" with descriptors of increasing sleepiness placed on odd numbers from 1 to 9. Participants completed the KSS by selecting the appropriate number on a computer keyboard.
Neurobehavioral performance was assessed every other hour throughout the 30-h extended wake episode using the visual psychomotor vigilance task (PVT),49 a task of sustained attention shown to be a reliable index of objective drowsiness.17,18,50 Here, participants placed their dominant thumb on the response button, responding as quickly as they could to a millisecond counter which appeared in a small rectangle box in the center of the screen (PVT stimulus). Random inter-stimulus intervals ranged from 1-10 sec, and task duration was approximately 10 min (∼90 stimulus presentations). PVT lapses were defined as response times ≥ 500 msec. Neurobehavioral testing started 2 h after wake time, resulting in 14 tests across the 30-h constant routine.
During the entire protocol, participants reclined in bed at a 45° angle in a hospital bed with the head of the bed elevated. While taking the neurobehavioral assessment, the computer screen was located at eye level and 53 cm away from the face, and participants completed KSS and PVT tasks using the keyboard and response box as laid out in front of them.
Core body temperature (CBT) was measured every minute by a rectal thermistor (Measurement Specialties TPG, Dayton, OH). CBTmin, which was estimated using a nonorthogonal spectral analysis technique as described in detail elsewhere51,52 was used as the marker of the circadian clock. Participants removed the sensor for bowel movements. Room temperature was maintained at 75° ± 3°F.
For analyses with respect to time awake, all ocular parameters were averaged in hourly bins 1 h post-wake. For analyses with respect to circadian time, all ocular parameters were averaged in 1-h bins relative to CBTmin. To establish any effects within participant for time awake or time since CBTmin, we performed PROC MIXED (SAS 9.2) analyses, as this accommodates missing data. In addition, to achieve predictions at the participant level, participant was modeled as a random effect and time awake, or circadian time was modeled as a fixed effect, using the Kenward-Rogers method to calculate degrees of freedom. An auto-regressive co-variance structure was used for repeated measures.53 Post hoc comparisons for any main effect of time awake or time since CBTmin were made using pairwise comparisons with Bonferroni-Holm corrections for multiple comparisons. To reduce type I errors for post hoc testing, for time awake we compared each time bin after 16 h awake versus the average of the first 16 h awake (based on wake beyond 16 h being a near-linear predictor of performance6). Here, data for the first 16 h were averaged to form one value. For circadian time, we compared each hourly bin after Tmax (estimated as occurring, on average, ∼13 h prior to Tmin according to Wyatt et al.54) against an averaged "wake" reference point. Here, data were averaged between Tmax and Tmax-8h to form one value (8 h preceding Tmax was the cutoff, as this is associated with the melatonin low point associated with the wake episode54).
Ocular parameters in the 10 min preceding the neurobehavioral test battery were averaged and compared to PVT performance and KSS ratings during the subsequent test session. PVT data were normalized by log transformation of mean reaction time and the slowest 10% of responses and total PVT lapses ≥ 500 msec normalized by expressing the total number of lapses as a function of √(n)+√(n+1). Within participant correlation coefficients were calculated using Pearson correlation analysis to determine the relationship between each ocular parameter and corresponding subjective/objective drowsiness levels for each individual, to examine individual differences in coefficients.
ROC analysis was used to evaluate the relative strength of each ocular parameter in predicting drowsiness according to a predefined threshold based on laboratory-based measures of drowsiness (KSS, PVT). KSS threshold was defined as ≥ 6 ("greater than some signs of sleepiness"). As no threshold exists for determining an "impaired" versus "non-impaired" PVT test, as per Chua et al.,16 a binary classification task was used to identify an objective drowsiness threshold. Here, drowsiness was defined as a 50% or 75% increase in the number of PVT lapses, measured relative to the number of lapses in the first 16 h awake during the 30-h extended wake episode. Baseline performance was computed as threshold × range + baseline, where "range" was the difference between the baseline and maximum number of lapses for each individual, "baseline" was the median number of PVT lapses during the first 16 h of wakefulness, and "threshold" was either 0.5 or 0.75.16 Each PVT session was then categorized as "normal" if the number of lapses was below threshold or "impaired" if the number of lapses exceeded the threshold. For KSS, the threshold was set at 6, depicting self-reported drowsiness level at or above "some signs of drowsiness."
To assess the relative strength of each ocular parameter in predicting "normal" versus "impaired" performance or drowsiness for every neurobehavioral test for all participants, ROC curves (AUC) were constructed to examine the relative strength of each ocular metric for detecting the drowsy impaired state. Pre-test probability was estimated empirically from the data, which was p = 0.29 for a 50% increase in PVT lapses, p = 0.20 for a 75% increase in PVT lapses, and p = 0.35 for an increase in KSS. Cost-ratios were set at 0.5 for 50% increase in PVT lapses, 0.25 for 75% increase in PVT lapses, and 1.0 for KSS. These values were used to determine optimal cutoff points.
A linear mixed model compared average outcomes on the neurobehavioral test battery as a function of prior JDS (in bins JDS ≤ 1.4, 1.5 ≤ 2.4, 2.5 ≤ 3.4, 3.5 ≤ 4.4, ≥ 4.5). For any individual contributing > 1 PVT/KSS per JDS bin, data were averaged within participant, within JDS bin. Here, participant was used as a random effect and JDS bin as a fixed effect, using the Kenward-Rogers method to calculate degrees of freedom. An auto-regressive co-variance structure was used for repeated measures. Due to missing data for KSS and lapses (see results), participants no longer showed significant inter-individual differences and were modeled only with repeated measures. Post hoc pairwise comparisons with Bonferroni-Holm corrections are reported. Only JDS scores were applied in the dose response analysis because of their well-defined boundaries for changing drowsiness levels.
Linear mixed models were computed using SAS 9.2; ROC curves were constructed using SigmaPlot 11 (Systat Software Inc, San Jose, CA); and all other data were analyzed using IBM SPSS Statistics, Version 19 (SPSS Inc., New York, NY).
We present data from 28 of 29 participants who completed the inpatient segment of the study (n = 28). Data from one participant was excluded due to technological difficulties with the Optalert system. For circadian phase data, we present data on n = 24; n = 4 were not presented due to a loss of temperature and/or an inability to calculate CBTmin. The loss of this data was due to improper positioning of the sensor (n = 2), no use of the sensor due to prior risk of hemorrhoids (n = 1) and quality control of temperature data (n = 1). Data from n = 28 participants is presented for analysis on homeostatic (time awake) changes in drowsiness. In the 10-min interval preceding any neurobehavioral test, only data that met the highest signal quality checks for Optalert signals were included in the analysis. Intervals with poor signal quality were removed on an individual basis, unless they exceeded 50% of the total trials, in which case the participant was removed from all analyses (n = 7 participants). Of a total of 392 sessions (14 sessions*28 participants), 263 passed signal quality checks (67.2%). Of those who were excluded, 28 (7.1%) were excluded because of a variable baseline (improper positioning of the Optalert glasses); 2 (0.5%) were excluded because of a biphasic signal (picking up lower lid movement); 5 (1.3%) were excluded because no eye movements were detected; 6 (1.5%) were excluded because of the participants looking down underneath the barrel; and 88 (22.4%) were excluded because of a combination of these factors. For neurobehavioral data binned according to prior JDS (dose response), not all participants had JDS scores in each binned category: JDS < 1.49 n = 19; JDS 1.5-2.49 n = 23; JDS 2.5-3.49 n = 23; JDS 3.5-4.49 n = 22; JDS > 4.5 n = 13). Three PVT tests (from 2 participants) were removed for final analysis due to incorrect procedures (failure to adhere to study protocol [n = 1] and wrong button presses [n = 2]). Total PVT test sessions included in the analysis were 389/392 (99.2%). KSS data is presented from all 392 trials (100%).
Figure 1 shows hourly binned data for all ocular parameters over the 30-h CR. For analysis purposes, we collapsed hours 1-16 into one time point, in order to examine the effect of time awake (average 2-16th hour, average 17th hour, average 18th hour…average 30th hour). Linear mixed model revealed a significant main effect of time awake for JDS scores (F14,330 = 8.71, p < 0.0001; Panel A), AVR (F14,327 = 9.31, p < 0.0001; Panel B), long eye closures (F14,316 = 7.82; p < 0.0001; Panel C), inter-event duration (F14,333 = 2.43, p < 0.003; Panel D), total blink duration (F14,326 = 5.02, p < 0.0001; Panel E), and time with eyes closed (F14,321 = 6.59, p < 0.0001; Panel F). Paired t-tests comparing all time points after 16 h awake compared to the average of the first 16 h of wakefulness and are shown in Figure 1 (Panel A-F). Compared to an average of the first 16 h awake, after 30 h awake all ocular parameters reflected increased drowsiness: (JDS: 2.2 ± 0.19 vs. 3.4 ± 0.25; AVR: 1.86 ± 0.06 vs. 2.1 ± 0.07; long eye closure: 0.66 ± 0.10 vs. 2.9 ± 0.50; inter-event duration: 0.13 ± 0.01 vs. 0.18 ± 0.02; total blink duration: 0.46 ± 0.02 vs. 0.87 ± 0.10; and time with eyes closed: 1.99 ± 0.25 vs. 6.34 ± 0.97).
Following a main effect of time (p < 0.0001), post hoc tests with Bonferroni-Holm corrections comparing hourly bins to the average of the first 16 h awake are shown (▼ p < 0.05/k-1). Vertical line represents 16 h of wakefulness. Post hoc comparisons were made for each hourly bin after 16 h awake compared to the average value in the first 16 h, as represented by the horizontal line. Means ± SE are shown for (A) JDS, n = 392; (B) amplitude-velocity ratio, n = 392; (C) long eye closures per minute, n = 385; (D) inter-event duration, n = 392; (E) total blink duration per minute, n = 391; and (F) time with eyes closed per minute, n = 391.
Mean hourly ocular outcomes as a function of hours awakeFollowing a main effect of time (p
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To examine any potential confound of averaging the first 16-h interval, linear mixed models were repeated for all time points (2nd-30th) without averaging hours 1-16. Here, the significant main effect of time awake for hourly binned JDS scores (F28,691 = 7.59, p < 0.0001), AVR (F28,691 = 6.48, p < 0.0001), long eye closures (F28,688 = 4.45, p < 0.0001), inter-event duration (F28,696 = 2.87, p < 0.0001. Panel D), total blink duration (F28,682 = 4.56, p < 0.0001), and time with eyes closed (F28,688 = 4.45, p < 0.0001) remained. Pairwise comparisons of all time pairs are available in the supplemental material.
As participants entered the CR with varying schedules and prior light exposure history (see Methods), we conducted secondary analyses to examine any effect of protocol (Time Awake*Protocol) on ocular parameters using linear mixed model analyses. There was no effect of protocol (p > 0.4), nor any time awake*protocol interaction (p > 0.9), for any ocular parameter. Protocol was therefore not included in any further analyses.
As individuals entered the CR at unknown circadian phases, we examined JDS relative to circadian time (see supplemental material for the association between core body temperature minimum and time since wake for all participants). As seen in Figure 2, average hourly ocular outcome scores were computed and binned according to circadian time 0 (CBTmin), and compared using a linear mixed model to take into account missing values. For analysis purposes, we averaged CBTmax to CBTmax-8h to reflect one point versus all other hourly bins from CBTmax to 2 h after CBTmin. There was a significant main effect of circadian time for JDS (F16,306 = 12.37, p < 0.0001; Panel A), AVR (F16,306 = 8.79, p < 0.0001; Panel B), long eye closures (F16,306 = 4.35, p < 0.0001; Panel C); inter-event duration (F16,307 = 3.33, p < 0.0001; Panel D); total blink duration (F16,304 = 3.59, p < 0.0001; Panel E), and time with eyes closed (F16,297 = 4.11, p < 0.0001; Panel F). Post hoc tests with Bonferroni-Holm corrections compared all time points after CBTmax to the average reference interval of CBTmax to CBTmax-8h. As seen in Figure 2, compared to an average of CBTmax-CBTmax-8h ("alert"), all ocular parameters indicated increased drowsiness at CBTmin/CBTmin+1 (JDS: 2.26 ± 0.20 vs.3.29 ± 0.25; AVR: 1.88 ± 0.06 vs. 2.15 ± 0.08; long eye closure: 0.71 ± 0.13 vs. 1.32 ± 0.21; inter-event duration: 0.13 ± 0.01 vs. 0.16 ± 0.01; total blink duration: 0.46 ± 0.03 vs. 0.64 ± 0.09; and time with eyes closed: 1.91 ± 0.28 vs. 3.88 ± 0.70).
Following a main effect of time (p < 0.0001), post hoc tests show elevated JDS scores from CBTmax (13 h prior to CBTmin) versus the average of the 8 h preceding CBTmax (▼ p < 0.05/k-1). Vertical lines represent an estimate of the start and end of biological night,51,56,57 and the horizontal line represents the average value used as the reference point for post hoc testing. Means ± SE are shown for (A) JDS, n = 372; (B) amplitude-velocity ratio, n = 367; (C) long eye closures per minute, n = 367; (D) inter-event duration, n = 3,364; (E) total blink duration per minute, n = 3,368; and (F) time with eyes closed per minute, n = 368.
Mean hourly ocular outcomes as a function of circadian timeFollowing a main effect of time (p
As shown previously for time awake, to examine any potential confounds of averaging CBTmax-CBTmax-8h to form reference value, we repeated the linear mixed model analyses for all time points (CBTmin-23h to CBTmin +2h) without averaging of any circadian time points. The significant main effect of circadian time remained (JDS [F25,503 = 8.7, p < 0.0001], AVR [F25,498 = 6.35, p < 0.0001], long eye closures [F25,4893 = 3.4, p < 0.0001]; inter-event duration [F25,496 = 3.03, p < 0.0001]; total blink duration [F25,492 = 3.01, p < 0.0001], and Time with Eye Closed [F25,483 = 2.89, p < 0.0001]). Post hoc comparisons for all data points can be seen in the supplemental material.
To compare sensitivity and specificity of different ocular outcomes for predicting drowsiness according to standard laboratory-based measures of drowsiness, we constructed receiver operator characteristic curves for subjective (KSS) and objective (PVT) thresholds for drowsiness. KSS ≥ 6 ("some signs of sleepiness" or above) was used as a subjective threshold for drowsiness. As no cutoff exists that describes a level of "impaired" performance or well-defined threshold for drowsiness on the PVT, partly due to strong individual differences in "impaired values," we determined varying levels of impairment as a 50% or 75% increase in lapses compared to baseline (see Methods). Notwithstanding circadian fluctuations, for most individuals, average PVT lapses exceeded the 50% threshold during the subjective night (∼22 h awake), whereas the average 75% threshold occurred close to habitual wake time (∼24 h awake). While all AUCs were significantly greater than 0.5 (p < 0.001), the highest AUCs were reported for JDS, followed by time with eyes closed. ROC curves for JDS versus PVT/ KSS can be seen in Figure 3. While AVR had the largest sensitivity value (0.88), this was only reliable for the highest level of impairment on the PVT. Sensitivity and specificity values were consistently better for JDS than all other ocular parameters, closely followed by long eye closures and time with eyes closed (Table 1).
Receiver Operator Characteristics curves demonstrating the sensitivity and specificity of JDS in detecting objectively defined drowsiness (50% increase in PVT lapses, left) and subjectively defined drowsiness (KSS ≥ 6, right). Optimal cutoffs for JDS were 2.75 and 3.11 for a 50% increase in PVT lapses from baseline and KSS ≥ 6, respectively.
Receiver Operator Characteristics curvesReceiver Operator Characteristics curves demonstrating the sensitivity and specificity of JDS in detecting objectively defined drowsiness (50% increase in PVT lapses, left) and subjectively defined drowsiness (KSS ≥ 6, right). Optimal cutoffs for JDS were 2.75 and 3.11 for a 50% increase in PVT lapses from baseline...
Sensitivity, specificity, and area under the curve (AUC): ocular parameters versus objective and subjective thresholds for drowsiness
Based on ROC analyses we determined the cutoff value for JDS in detecting drowsiness according to a 50% increase in PVT lapses from baseline as JDS = 2.75. Using as more stringent criteria of a 75% increase in PVT lapses from baseline, the cutoff value for JDS was 2.62 and for subjective levels of drowsiness (KSS ≥ 7), the optimum cutoff value for JDS was 3.11. JDS values between 2.5 and 4.5 were associated with varying levels of sensitivity and specificity (Table 2).
Sensitivity and specificity values associated with JDS thresholds of 2.5-4.5
Within subject correlation coefficients were calculated to examine the relationship between all ocular parameters and drowsiness at measured by the KSS and PVT over time for each individual (see Table 3). The percentage of individuals who exhibited significant statistical relationships is shown.
Average individual correlation coefficients (r) and the percentage of individuals (%) who demonstrate significant relationships between ocular parameters and gold standard measures of objective and subjective drowsiness
As seen in Figure 4, the average change in drowsiness levels as reflected by the JDS had similar temporal patterns of change as average PVT and average KSS. Averaged objective and subjective sleepiness levels (average PVT; average KSS) following JDS scores of ≤ 1.49, 1.5 to 2.49, 2.5 to 3.49, 3.5 to 4.49, and ≥ 4.5 were examined. Here JDS scores in the 10 min preceding the neurobehavioral test battery were averaged and compared against mean RT, mean slowest 10%, and mean number of lapses. As seen in Figure 5, JDS scores were indicative of neurobehavioral performance in a dose-response manner. Linear mixed model analyses revealed significant main effect of prior JDS on mean RT (F4,62.2 = 6.53, p = 0.0002), mean number of lapses (F4,73.9 = 9.05, p < 0.0001), mean slowest 10% responses (F4,57.8 = 7.71, p < 0.0001), and KSS (F4,72.4 = 9.40, p < 0.0001). Post hoc tests are shown in Figure 5.
Change in objectively defined drowsiness over time according to mean (A) JDS, (B) RT, (C) number of lapses, (D) slowest 10% of responses and (E) KSS. All measures show an exponential increase, indicating increased drowsiness, after 16 h awake.
Change in objectively defined drowsinessChange in objectively defined drowsiness over time according to mean (A) JDS, (B) RT, (C) number of lapses, (D) slowest 10% of responses and (E) KSS. All measures show an exponential increase, indicating increased drowsiness, after 16 h awake.
Dose-response relationship between average JDS score leading up to neurobehavioral battery and the subsequent drowsiness response. Increasing mean JDS scores are associated with increased mean response time, mean number of lapses, increased mean slowest response times and increased mean KSS. JDS < 1.49, n = 19; JDS 1.5-2.49, n = 23; JDS 2.5-3.49, n = 23; JDS 3.5-4.49, n = 22; JDS > 4.5, n = 13.
Dose-response relationshipDose-response relationship between average JDS score leading up to neurobehavioral battery and the subsequent drowsiness response. Increasing mean JDS scores are associated with increased mean response time, mean number of lapses, increased mean slowest response times and increased mean KSS. JDS 4.5, n = 13.
Evidence-based tools to quantify changes in drowsiness are a fundamental part of accurately understanding major physiological determinants of alertness. Using a commercially available technology employing infrared reflectance oculography to detect small, transient changes in ocular parameters, we demonstrated the usefulness of these parameters in identifying the drowsy state, and demonstrated their consistency with established laboratory-based standard measures of both subjective (KSS) and objective (PVT) drowsiness.
As drowsiness fluctuates according to homeostatic and circadian regulatory processes,54,55 ocular signals that reflect this dynamic state should increase as a function of time awake and during the biological night. Here, we report that the amplitude-velocity ratio of an eye movement, the percentage of long eye closures (> 10 msec), total blink time duration, and percentage of time the eyes were closed increased following > 24 h time awake and during the biological night, consistent with previous studies reporting drowsiness-associated increases in blink duration22,24–26,56–58 and/or eye closure.7,21–23,56,57 Combining these output parameters via a proprietary algorithm, Optalert technology provides an additional index of drowsiness called the Johns Drowsiness Scale (JDS). Consistent with previous studies,32,33 compared to other ocular parameters from which the composite JDS is derived, we found the JDS to be the most sensitive marker of drowsiness due to time awake and during the biological night.
Previous studies have identified a drowsiness threshold of JDS 4.5 for identifying impaired performance while driving32; increased lane variability is clearly associated with this threshold. Using receiver operator characteristic curves to determine the most sensitive/specific threshold for drowsiness detection in a laboratory non-driving setting, we reported cutoff scores for depicting drowsiness-related impairment ranging between 2.6 and 3—substantially lower than driver simulation studies. Our data suggest that when using a JDS threshold of 2.75, 76% of incidences associated with a 50% increase in PVT lapses from baseline would be detected. In comparison, as shown in Table 3, using previously recommended thresholds of JDS 4.5 based on driving impairment, we would only detect 18% of cases where PVT lapses were elevated 50% above baseline levels. Two major implication of this revised cutoff score include: (1) Future laboratory studies which may pursue this system for detecting drowsiness should refrain from using the JDS 4.5 as a marker of drowsiness but instead employ JDS 2.75 as described here; and (2) as we demonstrate JDS scores of 2.75 to be reliably associated with increased PVT lapses and delayed response time, which are essential for safe driving practice, future employment of this device whether scientific or practical should not assume that a JDS < 4.5 is indicative of safe driving or as a lack of drowsiness: previous studies have shown this to be associated with the car leaving the carriageway,33 which is an extreme level of drowsiness. As shown here, lower JDS levels may be indicative of earlier, lower levels of drowsiness as detected by the PVT. However, further driver simulation-based work is required before the threshold should be lowered for warning of impaired driving as this would impact on the number of false alarms.
Caffier et al.22 captured numerous eye lid closures using infrared reflectance oculography and surmised that blink duration was the most informative parameter for detecting drowsiness, essentially due to the delay of lid reopening time. While we did not find blink duration to be the most informative ocular parameter depicting drowsiness, this was likely because our study captured more sensitive ocular parameters not obtained by Caffier et al. (i.e., AVR, JDS). As seen in Figure 1, we demonstrated a clear increase in JDS and AVR following 16 h of time awake. As these measures principally reflect a delay in lid reopening, this corroborates the interpretation by Caffier et al. that drowsiness preferentially delays lid reopening.22 An additional advantage of JDS and AVR is reduced inter-individual differences in the signal39,59 commonly found to be problematic in other ocular signals, such as blink rate or blink duration.22,26,27 AVR remains stable in the alert and drowsy state on the downward phase (lid closing) with a large blink having a corresponding fast velocity. However, when drowsy, velocity is delayed on the upward phase, resulting in a steeper slope such that velocity is slower irrespective of the amplitude.39
Previous studies have described PERCLOS as a sensitive biomarker of drowsiness.16,42,43 Despite this we were unable to compare this against the ocular metrics generated by the Optalert system. While PERCLOS is based on the percentage of time the eyes are closed > 80%, we examined the percentage of time the eyes were fully closed (Total Eye Closure). For this output parameter, we reported lower AUCs for 50% and 75% increases in lapses than those reported by Chua et al.,16 likely due to a more stringent criteria (full closure vs. 80% closure). Despite this, percentage of total eye closure remained a sensitive marker of drowsiness-related impairment in our study.
As similarly shown by Cajochen et al.,7 the ocular outcomes examined here showed clear circadian changes such that there was a sharp rise in JDS and all other ocular measures during the biological night, estimated using core body temperature based on previous work in our laboratory.54,60,61 As evident in Figure 2, JDS and AVR were maximal just after circadian time 0 in our study, which is consistent with previous studies that report maximal impairment in cognitive throughput, short term memory, alertness, and psychomotor vigilance just after the core body temperature nadir.54
In further comparing JDS to objective and subjective markers of drowsiness, there was a clear association between increasing JDS scores and subsequent psychomotor vigilance, including attention lapses and subjective ratings of drowsiness (KSS), in a dose-response manner. In addition, sensitivity and specificity scores for detecting the drowsy state were higher for JDS than all other ocular outputs (except AVR which had high sensitivity for detecting a 75% increase in lapses, yet the corresponding specificity was poor). Of particular relevance, our study used JDS scores to predict performance over the next 10 min, in contrast to previous studies33 that have used JDS scores occurring simultaneously with poor performance. Our study is novel in this respect. This tight coupling between ocular indices of drowsiness and subsequent performance impairment demonstrates that drowsiness can be predicted by ocular movements prior to performance impairment, and also in real time. For instance, JDS has previously been associated to simultaneous RT,32 although only two data points were examined (normal sleep versus 27-33 h awake). As our study further examines the change in JDS and ocular parameters due to drowsiness by examining change over 30 h awake, these data build on the current literature on the association between ocular parameters and objectively defined measures of drowsiness.
The sensitivity of eye movements to the drowsy state has a clear physiological basis. Eye movements provide a direct insight into central nervous system function and physiological changes in vigilance via direct feedback from the midbrain reticular formation.20 Eye closures are controlled primarily by the interaction of two muscles: the levator palpebrae, which maintain an open lid when active, and the orbicularis oculi, which contract to close the lid.62 With increasing drowsiness, changes in the afferent limbic signals reduce the activity of the levator palpebrae motoneuron, culminating in a closed eye.63 As the JDS reflects a delay in lid reopening, ostensibly driven by changes in AVR as the ratio is altered by slower eye reopening velocities, this metric provides a measurement of vigilance likely reflective of vigilance at the neural level. Together, these findings suggest that infrared reflectance oculography, and in particular the JDS output parameter (Optalert) provides a clear indication of drowsiness in the laboratory setting.
Our study was conducted in a highly controlled, distraction-free laboratory environment, which included participants remaining largely immobile for the duration of the protocol (a requirement of the constant routine for circadian biomarkers51). As such, this study does not assess the viability of this technology in real-world setting where environmental noise is present and participants are not confined to the laboratory bed. As described here, we made thorough signal quality checks and discarded data due to poor signal quality in a stringent manner similar to that done for electroencephalographic data. Due to methodological constraints, infrared reflectance oculography was measured at all times except during PVT testing, when the glasses were removed (due to a head-based eye tracker being used during that time). As a result, the glasses were removed and replaced 15 times during the 30-h constant routine which may have resulted in the glasses being misplaced at times and may have accounted for some of our poor signal issues due to improper positioning of Optalert glasses. In addition, following extended duration of time awake, our participants would occasionally tilt the head back, forcing the eyes to look down under the barrel. This resulted in poor signal quality which led to post hoc exclusion of data from the analysis.
Irrespective of these caveats, we systematically evaluated the use of infrared oculography as a tool to monitor several ocular parameters to depict dynamic changes in the drowsy state. Here, we report that the strongest predictors of drowsiness included JDS, AVR, and percentage of long eye closures, with JDS being the most promising index of drowsiness. Consistent with previous studies,32,33 we conclude that the technology employed here and its composite JDS output (JDS), is an exciting technology that holds promise to be an effective research tool within the laboratory; the system requires no calibration, is relatively nonintrusive, and is well tolerated for long periods of time by participants. Furthermore, with more appropriately defined cutoff/thresholds for impairment, this system may be a useful tool in future studies evaluating changes in drowsiness due to sleep loss, circadian misalignment, pharmacologically driven sedation effects and the impact of countermeasures. However, for detection of drowsiness under these circumstances, we suggest lowering the threshold considered "drowsy." Overall, these data provide evidence that ocular output parameters recorded via infrared oculography, and in particular the composite JDS output derived from these parameters, has a strong potential to be an effective evidence-based tool for quantifying changes in drowsiness in the laboratory, combined or in the absence of existing laboratory-based measures.
This was not an industry supported study. Dr. Anderson reports receiving a research award/prize from Sanofi-Aventis; contract research support from VicRoads; and lecturing fees from Brown Medical School/Rhode Island Hospital and Ausmed. In addition, she has served as consultant to the Rail, Bus and Tram Union to produce a report on best practice management of fatigue in the rail industry, through an agreement between Monash University and the Rail, Bus and Tram Union. Since completion of this study, Monash University, for which Dr. Anderson now works, has received equipment on loan from Optalert TM, for a separate study. Dr. Czeisler has received consulting fees from or served as a paid member of scientific advisory boards for: Actelion, Ltd.; Astra Zeneca; Avera Pharmaceuticals, Inc.; Bombardier Inc.; Boston Celtics; Celadon Trucking Services; Cephalon Inc. (acquired by Teva Pharmaceutical Industries Ltd. October 2011); Columbia River Bar Pilots; Delta Airlines; Eli Lilly and Co.; Federal Motor Carrier Safety Administration (FMCSA), U.S. Department of Transportation; FedEx Kinko's; Fusion Medical Education, LLC; Garda Síochána Inspectorate; Gerson Lehrman Group for Novartis; Global Ground Support; Hypnion, Inc. (acquired by Eli Lilly and Co. in April 2007); Johnson & Johnson; Koninklijke Philips Electronics, N.V.; Minnesota Timberwolves; Morgan Stanley; Norfolk Southern; Portland Trail Blazers; Respironics, Inc. (acquired by Koninklijke Philips Electronics, N.V. in March 2008); Sanofi-Aventis Groupe; Sepracor, Inc.; Sleep Multimedia, Inc.; Sleep Research Society (for which Dr. Czeisler served as president); Somnus Therapeutics, Inc., Takeda Pharmaceuticals, Vanda Pharmaceuticals, Inc., Vital Issues in Medicine, Warburg-Pincus, and Zeo Inc. Dr. Czeisler owns an equity interest in Lifetrac, Inc.; Somnus Therapeutics, Inc.; Vanda Pharmaceuticals, Inc., and Zeo Inc., and received royalties from CNN; the Massachusetts Medical Society/New England Journal of Medicine; McGraw Hill, the New York Times; Penguin Press/Houghton Mifflin Harcourt; and Philips Respironics, Inc. Dr. Czeisler has received lecture fees from the AWHONN (Association of Women's Health, Obstetric and Neonatal Nurses) Accreditation Council of Graduate Medical Education; Alfresa; the Alliance for Epilepsy Research; the American Academy of Allergy, Asthma and Immunology Program Directors; American Academy of Sleep Medicine; American Physiological Society; Association of University Anesthesiologists; Axis Healthcare, LLC; Baylor College of Medicine; Beth-Israel Deaconess Medical Center; Brown Medical School/Rhode Island Hospital; Cephalon, Inc.; Clinical Excellence Commission (Australia); Dalhousie University; Duke University Medical Center; Duke University School of Medicine; Harvard School of Public Health; Harvard University; Hokkaido University Graduate School of Medicine; Institute of Sleep Health Promotion (NPO); Japan Aerospace Exploration Agency (JAXA); LOTTE Health Products; London Deanery; Morehouse School of Medicine; Mount Sinai School of Medicine; National Academy of Sciences; National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK/NIH); National Institutes of Health; National Sleep Foundation; New England College of Occupational and Environmental Medicine (NECOEM); North East Sleep Society; Office of Rare Diseases Research (NIH); Osaka University School of Medicine; Partners HealthCare, Inc.; Rockpointe; Sanofi-Aventis, Inc.; Sleep Research Society; Society for Obstetric Anesthesia and Perinatology (SOAP); Society of Thoracic Surgeons; St. Lukes Roosevelt Hospital; Takeda; Tanabe Seiyaku Co., Ltd.; Tokyo Electric Power Company (TEPCO); U.S. Fire Administration Executive Fire Officer Program [formerly listed as National Emergency Training Center]; University of Chicago; University of Colorado University of Michigan; University of Pennsylvania; University of Pittsburgh; University of Tsukuba; University of Virginia Medical School; University of Washington Medical Center; University of Wisconsin Medical School; World Federation of Sleep Research and Sleep Medicine Societies and WME Entertainment LLC. Dr. Czeisler has also received research prizes with monetary awards from the American Academy of Sleep Medicine; American Clinical and Climatological Association; Association for Patient-Oriented Research; National Institute for Occupational Safety and Health; National Sleep Foundation; and Sleep Research Society; clinical trial research contracts from Cephalon, Inc., Merck & Co., Inc., and Pfizer, Inc.; an investigator-initiated research grant from Cephalon, Inc.; and his research laboratory at the Brigham and Women's Hospital has received unrestricted research and education funds and/or support for research expenses from Cephalon, Inc., Koninklijke Philips Electronics, N.V., ResMed, Committee for Interns and Residents and the Brigham and Women's Hospital. The Harvard Medical School Division of Sleep Medicine (HMS/DSM), which Dr. Czeisler directs, has received unrestricted research and educational gifts and endowment funds from: Boehringer Ingelheim Pharmaceuticals, Inc., Cephalon, Inc., George H. Kidder, Esq., Gerald McGinnis, GlaxoSmithKline, Herbert Lee, Hypnion, Jazz Pharmaceuticals, Jordan's Furniture, Merck & Co., Inc., Peter C. Farrell, Ph.D., Pfizer, ResMed, Respironics, Inc., Sanofi-Aventis, Inc., Sealy, Inc., Sepracor, Inc., Simmons, Sleep HealthCenters LLC, Spring Aire, Takeda Pharmaceuticals, and Tempur-Pedic. The HMS/DSM has received gifts from many outside organizations and individuals including: Aetna US Healthcare, Alertness Solutions, Inc., American Academy of Sleep Medicine, Boehringer Ingelheim Pharmaceuticals, Inc., Brigham & Women's Hospital (Department of Medicine), Brigham & Women's Hospital (Development Office), Bristol-Myers Squibb, Catalyst Group, Cephalon, Inc., Clarus Ventures, Comfortaire Corporation, Committee for Interns and Residents, Eisai, Inc., Eli Lilly and Co., Farrell Family Foundation, Fisher & Paykel Healthcare Corporation, George H. Kidder, Esq., GlaxoSmithKline, Gerald McGinnis, Gosule, Butkus & Jesson, LLP, Herbert Lee, Hypnion, Inc., Innovative Brands Group (Nature's Rest), Jordan's Furniture, King Koil Sleep Products, Land and Sky, Lilly USA, LLC, Merck Research Laboratories, MPM Capital, Neurocare Center for Sleep, Neurocrine Biosciences, Inc., NeuroScience, Novartis Consumer Health, Orphan Medical/Jazz Pharmaceuticals, Park Place Corporation, Pfizer Global Pharmaceuticals, Pfizer Healthcare Division, Pfizer, Inc., Philips-Respironics, Inc., PR21, Praxair US Homecare, Purdue Pharma L.P., Ramiro Sanchez, Jr. M.D., ResMed, Inc., Respironics, Inc., Safeway, Sanofi-Aventis, Inc., Sanofi-Synthelabo, Sealy Mattress Company, Sealy, Inc., Select Comfort Corporation, Sepracor, Inc., Simmons Co., Sleep Ave, LLC, Sleep HealthCenters LLC, SleepCare, LLC, Somaxon Pharmaceuticals, Spring Air Mattress Co., Synchrony Healthcare Communications, Takeda Pharmaceuticals, Tempur-Pedic Medical Division, Total Sleep Holdings, Transcept Pharmaceuticals, Vanda Pharmaceuticals, Inc., Wake Up Narcolepsy, Inc., Watermark Medical, Weight Watchers International, YMCA of the USA, the Zeno Group and Zeo, Inc. (formerly Axon Sleep Research Laboratories, Inc.) The HMS/DSM Sleep and Health Education Program has received Educational Grant funding from Cephalon, Inc., Sanofi-Aventis, Inc. Sepracor, Inc., and Takeda Pharmaceuticals, Dr. Czeisler is the incumbent of an endowed professorship provided to Harvard University by Cephalon, Inc. and holds a number of process patents in the field of sleep/circadian rhythms (e.g., photic resetting of the human circadian pacemaker). Since 1985, Dr. Czeisler has also served as an expert witness on various legal cases related to sleep and/or circadian rhythms. The other authors have indicated no financial conflicts of interest.
The authors thank the study participants, the staff of the Center for Clinical Investigation of the Brigham & Women's Hospital, and the staff of the Chronobiology Core for monitoring of study equipment. We also thank our recruiter Mr. David Klements for his assistance, and Mr. Sean Dunne for his technological skills. We acknowledge Mr. Jeff Tarpy for assistance in equipment set-up, and Mr. Robert Kilpatrick for assistance in pilot testing.
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The data as described in this manuscript was obtained from the 30 hour constant routine period. OptalertTM data was obtained continuously and neurobehavioural data was obtained bi-hourly starting 1 hour after wake time during this period.
*30 hour constant routine indicted by gray shaded area on days 7 and 8.
Example of Study Protocol*30 hour constant routine indicted by gray shaded area on days 7 and 8.
Time of Core Body Temperature Minimum: Real Clock Time and Time Since Waking


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Professor Norman Lichtenstein was an active member of the Pace Law School faculty for over 25 years. He previously served as executive director of Westchester Legal Services and was a member and past president of the White Plains Board of Education. He also counsel to the New York State Joint Legislative Committee on Consumer Protection and was a member of the Citizens Union Committee on State Legislation. He is a past member of the Family Court Law Guardian Advisory Committee for the Ninth Judicial District of the Second Judicial Department. He has published articles on retroactive relief in the federal courts as impacted by the Eleventh Amendment, the right to know for children in schools and fault as a factor in distribution of property at divorce. His primary teaching areas include courses on Professional Responsibility and Law and Education.
"Children, the Schools, and the Right to Know: Some Thoughts at the Schoolhouse Gate." San Francisco Law Review 91 (1985).
"Marital Misconduct and the Allocation of Financial Resources at Divorce: A Farewell to Fault," 54 UMKC Law Review 1 (1985).
"Retroactive Relief in the Federal Courts Since Edelman v. Jordan: A Trip Through the Twilight Zone," 32 Case Western Reserve Law Review 364 (1982).


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Steve Kovach, Business Insider
Just like it said it would, Google made its Nexus 4 Android smartphone available for sale again in the US.
Shoppers who went to the Google Play store briefly saw an 8 GB model going for $299, shipping in 4-5 weeks.
In less than half an hour, it was sold out again.
LG makes the Nexus 4 for Google, which chooses manufacturing partners to make Nexus-branded Android phones and tablets.
DON'T MISS: Nexus 4 Review >


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ORLANDO, Fla. - A group gathered in downtown Orlando on Saturday to light candles and pray for those suffering in Boston.
"We can't give them their limbs back, OK, we can't bring the little boy that lost his life, we can't bring him back, but what we can do is we can pray for them," said Shyand Mosby, who organized the vigil.
The group prayed for 8-year-old Martin Richard, 23-year-old Lu Lingzi, and 29-year-old Krystie Campbell, the three who were killed in Monday's attack.
They prayed for the runners, spectators, and the children who were injured, more than 170 people whose lives will be forever touched by the bombings.
"These attacks are serious, they're real, they're not at our back door, they're at our front door," said Mosby.
Before the arrest of the surviving suspect, one more life would be taken, Sean Collier, 26, the MIT officer who was shot five hours after the FBI released surveillance photos of the two men they say planted the twin bombs near the finish line.
"The police men and those that actually had to do their job, and had to give up their lives, they were hurt in the process of helping somebody else," said Joyce Elliott. "We want them to know that we commend them for what they did."
Copyright 2013 by ClickOrlando.com. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.


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Today: Glamour, or how to hide irony about gender stereotypes very well…
Or something like that… because as much as I think FOSS games should cater to the
other ermm… 2nd out of three(?) gender, I am not sure if this is meant ironic or not (description of the game Glamour):
You are Maddeline, a young princess just turned 16. Now you're old enough to attend the royal balls and your fairy godmother will help you get ready for the most exciting dances.Watch out your way while walking around this amazing city full of filthy foes. They may harm your look. You wouldn't like to reach the ball all covered with dirt.
Visit the Make-up, Shoe, Dress and Accessory Castle to find the most beautiful outfits and win the Prince Charming heart.
|At least I see relatively little pink on that screen-shot…
Source-code is available here for those that wonder…
*stalkes slowly away*
But -BAM-… here is something clearly more manly:
|Unvanquished Alpha 19
-BAM- check the alpha 19 changelog -BAM- Oh and the soon to released AlienArena Tactical also sound like a game for -BAM- real men!
Hmm BAM?