Brain development and football.

A few days ago I posted about decision making in football, and apparently I wasn't the only brain blogger to be thinking about the pigskin over the holiday weekend. Jared Tanner, over at BrainBlogger, put forward the hypothesis that one of the reasons most college teams don't start freshman quarterbacks has to do with their underdeveloped prefrontal cortices, which leaves them less able to make good split-second decisions.  It is an interesting idea, and there is some basis to think that the brain of an 18 year old would look a bit different from a 22 year old's.  Still, there are numerous experiments that would need to be done just to demonstrate that junior or senior quarterbacks really perform that much better than freshman or sophomores, and that any difference in performance is not related to experience with the team, the coaches, the types of plays being run, etc.  After all, my alma mater, Penn State, started a freshman QB named Rob Boulden this year, and he played pretty well, up until he got a head injury... which would be another variable that would have to be controlled for in any study of the brains of football players.

Sunday Comics

Another good one from SMBC....

Thanksgiving Re-post

Since some people may not think a football related post is "thanksgivingy" enough, here is a re-posting from last year: Does turkey on thanksgiving really make you sleepy?

Since Turkey-day is around the corner, I thought I would bring up the very popular myth that tryptophan in turkey is what makes us all feel groggy on Thanksgiving.  In an earlier post, I talked about how the amino acid tryptophan gets converted into serotonin, and then melatonin.  Melatonin, as you may or may not know is the "sleep hormone". It is secreted by the pineal gland to help regulate our sleep/wake cycles which follow a circadian rhythm of about 24-25 hours.  During the day, when it is bright and sunny we feel awake, then, as the day turns into night, we start producing more melatonin, and we get sleepy.  Considering this, it's not too hard to see why tryptophan became the scapegoat for our Thanksgiving day sleepiness, but the truth is tryptophan, or really turkey in general has gotten a bad rap.  First, tryptophan is a fairly prevalent amino acid, and there is actually plenty of it in most of the protein containing foods that we eat.  Furthermore, turkey does NOT contain a higher level of tryptophan than most other common meats, fish, and poultry.  For example, per 200 calorie serving, duck, pork, chicken, soy, sunflower seeds, several types of fish, and turkey all have about 440 - 450 mg of tryptophan, with turkey being the lowest in the group.  Of course, that being said, even if turkey did have significantly more tryptophan than other meats, it is still questionable as to whether normally consumed levels of tryptophan can make you sleepy.  While at first glance, the research seems to back the idea that tryptophan has sedative properties, these studies have used very large quantities to test for these effects. For example, one study from 1975 suggested that consuming 5 grams of tryptophan (so, about 11 servings of turkey) did increase self-reported drowsiness, and a study conducted in 1989 found that a dose of 1.2 grams of tryptophan did NOT increase measures for drowsiness, but a dose of 2.4 grams did.  These studies suggest that you would have to eat a lot of turkey (like, over a pound and a half) to get an effective dose.  So, while it is possible that you may eat that much turkey on our most hallowed of gluttonous holidays, it is more likely that thanksgiving day drowsiness is the result of a coming together of many factors, a perfect storm if you will, of:
1. lots of food (which diverts bloodflow to the digestive tract),
2. carbohydrate loading, where much of the food is carbohydrate heavy stuffing and sweet foods like cranberry sauce, sweet potatoes, and desserts (which can cause an overproduction of insulin resulting in low blood sugar, and thus sleepiness, later on),
3. and then of course there are usually a couple of alcoholic beverages involved (with obvious sleep inducing effects). 
Add all of that up with being  in a nice, warm home, on a comfy couch, with football or parades or a fire flickering in the background, and what you have is a recipe for a nap.  I'm kinda sleepy just thinking about it.
Have a Happy Thanksgiving!

Thanksgiving and Football: Why you should always go for it on 4th and short

Today being Thanksgiving, it's pretty reasonable to assume (if you live in the U.S.) that you will likely be sitting down to a large meal involving lots of turkey, stuffing, and cranberry sauce.  It is also pretty likely, that somewhere in the house, football games will be on the television.  Which brings us to one of the quintessential questions in football: It's 4th down, your team is on the opposing team's 30 yard line and they have only one yard to go to get a first down.  Should they go for it?  Most people would probably say no... that they should try for a field goal and at least get the 3 points.  But most people would be wrong.  At least according to a study in the Journal of Political Economy (pdf), which suggests that the payoff for "going for it" is more than twice as much compared to trying for a field goal.
To completely over simplify the study, economist David Romer determined the payoff of each decision (either to kick or to go for it) by looking at thousands of NFL plays and calculating the average costs and benefits of each decision depending on where the team was positioned on the field.  In this case, the benefit would be the likelihood of scoring a touchdown (valued at roughly 7 points*) or of scoring a field goal (valued at 3 points).  So, if teams that decide to kick when they are on their opponents' 30 yard line make the field goal an average of 33% of the time, then the benefit of kicking is assigned a point value of 1 (since a field goal is worth 3 points, and 33 percent of 3 points is 1 point).  Since teams that only have one yard to go when they are on the 30 yard line convert for a first down 64% of the time, and teams that are inside the 30 yard line score a touchdown about 40% of the time, the benefit of going for a first down is assigned a value of 1.8 (0.64 x 0.40 = 0.24, or a 24% chance of scoring a touchdown by going for it on 4th and 1, and 0.24 x 7 points = 1.8 points).  This means that "going for it" should result in scoring almost twice as many points than kicking, and this difference becomes even more exaggerated when we consider the costs.  In this case, a failed attempt either way results in giving the other team the ball on their own 30 yard line.  Scoring the field goal, or eventually a touchdown, will result in a kickoff which, on average, results in the other team getting the ball on their 27 yard line.  This means that, no matter what your team does in this situation, they are going to ultimately give the ball to the other team at about the 30 yard line, which gives the other team a chance at scoring relating to an average value of 0.62.  Thus -0.62 points is the cost associated with either kicking or going for it.  This means that the net benefit of going for the first down is 1.18 points, while the net benefit of kicking the field goal is 0.38 points.  So, while there is less of a chance that "going for it" will result in a touchdown, compared to a greater chance that your kicker will make the 40yard field goal, on average you will get more than THREE TIMES as much benefit if your team goes for it every time they have 4th and 1 on the 30 rather than kicking it every time you were in this situation.
So, why do coaches so rarely go for the first down?  It may be that, in these instances, coaches (and likely fans) fail to take into account the differences in values of touchdowns and field goals, seeing all types of "score" as being roughly equal in value even though touchdowns are more than twice as valuable as field goals.  Additionally, the costs are also poorly estimated.  For example, turning the ball over by a loss of downs seems to carry greater cost than turning it over in the form of a kickoff after scoring, even though the point values of these in our hypothetical are roughly the same.  These ideas tie into the explanation that Romer offers in the paper, suggesting that coaches may be succumbing to "loss aversion" type thinking.  Loss aversion is a phenomenon in psychology where people generally avoid a more rewarding choice when the lesser of the two options seems more like a sure thing.  For example, when offered a fifty percent chance of a $100,000 prize or a 100 percent chance for a $30,000 prize, most people choose the $30,000 prize because it is a sure thing.  However, the value of the first option has an average value of $50,000 compared to only $30,000 for the second option.  So, if you are only offered this choice once, it might make sense to take the sure thing, BUT, if, as in the game of football, you will face a choice like this many different times in a game or over the course of a season, it makes more sense to choose the option that has the higher average outcome.  And, of course, most people do realize which decision is the better one if you take away the "sure thing" aspect of one of the options.  For example, if you ask the same group of people whether or not they would go for a 5% chance at $100,000 or a 10% chance at $30,000, more people choose the 5% chance at $100,000, even though the relative difference between winning the prizes is the same as in the previous situation.  (If you want to know more about loss aversion, I suggest this post over at Jonah Lehrer's blog.)
In the case of football, most coaches (and fans) see a field goal as much more of a "sure thing" because the probability of a successful try is higher than the probability of ultimately scoring a touchdown, particularly if you are less than 30 yards away from the goal line. BUT, this neglects to take into account the point differences between a field goal (3) and a touchdown (7), and the costs associated with the opposing team's resulting field position.  To provide another example, Romer presents the situation of having a 4th down and goal on the 2 yard line, where a field goal really is a sure thing, but the chances of scoring a touchdown are about 3 in 7.  Here, the benefit is about the same (an average of 3 points per field goal attempt, and an average of 3 points per touchdown attempt).  However, the cost for both of these is NOT the same.  Since the field goal is all but guaranteed, that means that on average, the opposing team will then get the ball on their 27 yard line after the kickoff.  Whereas, if you go for the touchdown, there is a 4/7 chance that you will fail and leave the other team with the ball on their 2 yard line.  When you calculate the cost and benefit of each of those field positions, the kickoff results in a positive chance of 0.62 points for the opposing team, thus costing your team 0.62 points (on average), leaving a resulting net benefit for a field goal try at 2.38.  Leaving the other team on their own 2 yard line however, puts them at a serious disadvantage where they are more likely to turn the ball back over or get sacked in the endzone giving your team 2 points for a safety. The average value of this position is therefore actually negative (-1.5), and thus, the benefit of going for the touchdown is (3/7 x 7 =) 3, and the "cost" is (4/7 x -1.5 = -0.857), which, subtracting the cost from the benefit, yields a net benefit of 3.857 going for the touchdown (versus the net benefit of only 2.38 if you kick the field goal).
AND this calculus doesn't just apply to being on the thirty yard line, or the 2 yard line.  According to Romer's extrapolation, no matter where you are on the field, except for maybe behind your own 15 yard line, it makes more sense to go for the first down on 4th and short (less than 2-3 yards to go) than it does to punt or to kick a field goal.  Romer estimates that teams who adopt a strategy of "going for it" in these situations would be 5% more likely to win each game, and would at least win one extra game per season than they normally would for 3 out of every 4 seasons.  So, maybe Bill Belichick, who has a reputation for "going for it" on 4th down, has done his math, or maybe he has intuitively stumbled on to something.  Either way, his career coaching record of almost twice as many wins as losses, 3 Super Bowl rings and 4 AFC championships, support the idea that going for the first down conversion on 4th and short might just give your team the winning edge.  Just something to keep in mind while you are watching the games later this afternoon.  Happy Thanksgiving!

*Since point after touchdown ("extra point") kicks are successful 98.5% of the time, the actual value of a touchdown used in the study was 6.985, not 7, but for us, to keep the math simple, I'll just use the full 7.
__________________________________________________________________________________
And if you want to learn more about what various fields of research can tell you about your favorite sports, check out some of my earlier posts:

How the flash lag illusion may have cost Armando Galarraga his perfect game in baseball.

How magnetic necklaces and hologram bracelets may actually affect athletic performance.

How watching your favorite team win (or lose) might affect your testosterone levels.

Do you run a higher risk of getting a concussion playing boys" football or girls' soccer?

Where the students sit in the stadium could enhance your school's home field advantage.



Romer, D. (2006). Do Firms Maximize? Evidence from Professional Football Journal of Political Economy, 114 (2), 340-365 DOI: 10.1086/501171

The Top 7 research papers in Neuroscience

The Faculty of 1000 have come out with their rankings (for the year I guess?) and in the category of neuroscience,you can find summaries of the top 7 here.

Where art meets neuroscience

Last week's issue of the journal Nature had such a striking cover, that I couldn't help but pick one up off of the newsstand despite that fact that I can view the articles electronically at work.  The cover revealed that the focus of the issue would be schizophrenia, a disease where the causes remain poorly understood in the scientific community, and the symptoms even less so in the mainstream.  Many people often confuse schizophrenia with multiple personality disorder despite the fact that the most prominent symptoms of schizophrenia are paranoid delusions and auditory hallucinations, not multiple personalities.  Also, most people are generally unaware of the fact that schizophrenia typically manifests itself during late adolescence or early adulthood, which means that many who have schizophrenia can feel perfectly normal throughout their teens and even twenties before descending into the throes of this terrible disease.  There are, however, some promising discoveries being made, and, hopefully, they will lead to progress in treatments or even prevention of the disease, which is estimated to affect nearly 1 percent of the world's population.  At the nature website, you can check out many of the articles from the issue online which do a good job of summarizing some of the progress and many of the obstacles to understanding schizophrenia.  Of course, I started all of this by talking about art and neuroscience, and the cover of the magazine, the main portion of which is shown above.  The painting, which is credited to Rodger Casier, is an example taken from the NARSAD Artworks program which provides "museum quality art by artists whose lives share or have shared the bond of mental illness".  The program is an interesting one, not only raising awareness of mental illness by showcasing the artwork of those who have suffered or still suffered from some form of mental illness, but also raising money for mental health research as well.  I will have to check out the site a little more to see what's available (even just to look at), but in the meanwhile, with the holidays coming up, it may be a good place to go if you need to get some greeting cards (like the ones pictured below).

Cholesterol isn't all bad...

We've actually known this for quite some time, cholesterol does a lot of important things in cells and in your body, it just gets a bad wrap because when a lot of it gets carried around by low density lipoproteins, it can clog your arteries.  But cholesterol does lots of good things too, it improves the integrity of the cell membranes in all of your cells, and in many of the organelles within those cells.  It is also the molecule from which all of the steroid hormones are made (including estrogens and testosterone).  Some recent studies have also shown how critical cholesterol is for the development of the brain (an organ that is very rich with cholesterol) and the normal functioning of neurons.  The first study mentioned here shows how oxysterol (a metabolite, or breakdown product of cholesterol) seems to be important for the production of midbrain dopaminergic neurons (the type of cells that are lost in Parkinson's disease). The other study shows how cholesterol is important to normal brain function and the ability of neurons to communicate across synapses.  Some other important things that cholesterol does for us?  Well it is necessary for making vitamin D, it can have antioxidant properties (thus helping to prevent cell damage and cell death), and it can help our digestion of fat and fat soluble vitamins as a critical component of bile acids.  Of course, this doesn't mean that you should go out and start eating bacon and eggs for every meal.  Chances are that you are already getting plenty of cholesterol from you diet, and eating too much cholesterol in your diet can still be bad for your cardiovascular health, but the cholesterol that is made by the cells in your brain gets put to good use (as does the cholesterol made in most of your cells), it's just when you have to transport the stuff in your blood that it becomes a problem.   Also, there have been some studies to suggest that decreasing cholesterol synthesis with statins can reduce the risk of developing Alzheimer's disease, and there are other studies that suggest that high levels of cholesterol are correlated with a higher incidence of certain cancers, and there are even a couple new studies to suggest that even cholesterol that is being carried by high density lipoproteins (HDLs, or "good cholesterol") may be harmful if you have conditions such as diabetes, arthritis, or kidney dysfunction.  So, I guess the point is that cholesterol is a complicated molecule with lots of functions in the body, some good, some bad, and in the end we have to weigh what we know about the good and the bad to determine how we treat various diseases, though, given the effectiveness of lowering cholesterol on treating and preventing heart disease, and the prevalence of hear disease (it being the number one killer in the U.S.) I think we will still have to keep the general mindset that cholesterol is bad (at least that too much cholesterol is bad), but we don't want to completely eliminate it, because some cholesterol can be good (at least for your brain, and your cell membranes).

Society for Neuroscience Meeting

I am currently in San Diego for the annual meeting of the Society for Neuroscience.  I will hopefully be able to post some of the more interesting things I see here, but probably not in any sort of detail until after the meeting is over. In the meanwhile, there are several bloggers who will be updating regularly as the meeting goes on (like maybe they will blog about the talk given by actress Glenn Close who hopes to promote research and treatments for mental illnesses).  Anyway, you can find the list of bloggers (and tweeters) for the meeting here.

The Psychology of Climate Denialism

Probably more than anything else on this blog, I have posted about the denial of certain scientific facts (like global warming, evolution, and the safety of vaccines).  Second to that, I tend to post about the psychology that underlies such disbelief, like this post, where I recommend the ultimate resource in understanding why we tend to reject certain types of data.  Along these lines, I have been curious for a long time why research and data concerning how to persuade people, or to disabuse them of these mind blocks, is not more prevalent in discussions about things like global warming and the safety of vaccines.  While for most scientists, the data are the data, and these facts are readily accepted as such, there is clearly a disconnect with a substantial portion of the population.  For most scientists, myself included, simply repeating the facts, or shouting louder and louder, or finally name calling in frustration are the most common recourse when we are confronted with those who flatly deny the evidence (or worse, refuse to listen to or look at the evidence, claiming instead that it has all been fabricated).  Of course, hammering home the facts tends to work in lab meetings or at scientific conferences, but it doesn't seem to work at all in with climate deniers, evolution deniers, flat earthers, whatever.  So how do we convince the general public (or this proportion of it) that policies need to be enacted to stop global warming, or that they need to get their children vaccinated, etc.  It seems to me this problem is just as critical, if not more so, than the problems of global warming and autism themselves.  Because if people don't think global warming is real, they won't support public policies for change or for more research.  If people believe that the cause for autism is vaccines, they will harm others by not getting vaccinated, and, again, they may refuse to support publicly funded research to find the real causes of autism spectrum disorders.  So what can be done?  Well, I don't have any solid answers, but there are two interesting items I have come across recently that offer some hope.  The first is the cultural cognition project at Yale law school.  If you click on the link and go to the website, you can find several articles and scientific studies that have been sponsored by the program, like this one, which reviewed some of the experiments and showed that people's core beliefs are a major factor in determining how they view a particular scientific or technological issue.  This effect is particularly strong when the issue requires some additional level of expertise, causing us to rely on experts to explain things to us, or to tell us how to feel about a particular issue.  In these cases, the average person is much more likely to believe the "experts" that they feel they can identify with on core values.  This is very clearly illustrated by the fact that many will take Rush Limbaugh's opinions on global warming as fact despite his complete and utter lack of any scientific credentials.  People who identify with Limbaugh's conservative political and religious values see him as more of an "expert" than scientists who they may see as elitist, overly liberal, or atheistic, even when the issues at hand are scientific in nature.  Which, I guess, debunks the "shouting loudly and calling people stupid" method for persuading people of the veracity of scientific facts (sorry, PZ Myers).
Anyway, the second item that I found was much more directly related to climate denialism.  Recently, the American Psychological Association put out a report including "studies of human responses to natural and technological disasters, efforts to encourage environmentally responsible behavior, and research on the psychosocial impacts of climate change."  If you don't want to read the whole report (and I don't blame you) you can listen to an interview with a couple of the psychologists who helped to put together this report, here.  I don't know if this report really offers any solid answers, but it seems to do a decent job of identifying the problems we face with a public that does not accept or does not want to accept the consequences of it's polluting lifestyle.  It is encouraging to see that researchers are identifying these problems and trying to find solutions. Hopefully, this type of research and the resultant findings will gain a higher profile, and scientists and science reporters will have the tools they need to communicate most effectively with the public.  And beyond that, hopefully we will see a brighter future where society acts upon factual information (backed by mounds of scientific evidence) to make our world a better, safer place for future generations.  

More evidence against the "Grumpy old men" myth

A while back I posted about the idea we have in this country that the elderly are more likely to be sad, grumpy, curmudgenly, etc.  Despite this widespread belief, there are a handful of surveys that suggest that older people are generally happier than their young and middle aged counterparts (and generally more well adjusted).  Of course, since these surveys always asked different people (one group above a certain age versus another group at a middle age, etc.) one could hypothesize that times were simply better so many decades ago, thus arguing that the reason older people tend to be happier is because they grew up in some idealized "Leave it to Beaver" type culture, and the younger people are not as happy, not because of their age, but simply because they have had to live and grow up in a different world.  Well, a recent longevity study, that is, one that followed the same people as they aged, suggests that it really is age that confers feelings of well being.
http://www.sciencedaily.com/releases/2010/10/101028113819.htm
I guess they really are your golden years.

Magnetic necklaces, Holographic bracelets, and Other Totems in Sports

If you have watched any of the Major League Baseball playoffs recently, you can't help but notice the twisty, braided necklaces that have become an all too popular fashion accessory for many of the players.  Or maybe you have caught a glimpse of a shiny "power balance" bracelet on your favorite, baseball, football, or basketball player.  Of course, there is absolutely no evidence that any of these things actually have any of the amazing effects they claim (enhanced balance or stamina or overall athletic performance).  But then again, pro athletes have always been a superstitious bunch.  According to an article over at ESPN.com:

"SINCE THE BEGINNING of sport, athletes have looked outside themselves for an edge. In ancient Greece, Olympians sacrificed oxen to satisfy the gods. Roman gladiators entered the arena with their dominant foot first. Yogi Berra used the same Yankee Stadium shower during any winning streak.Michael Jordan wore UNC shorts under his Bulls uniform in every game for 13 years. And before Wade Boggs stepped to the plate, which he did more than 10,000 times in his 18-year career, he carved the Hebrew letters for the word chai ("life") into the dirt with his foot. And Boggs isn't Jewish."


Of course, as the article goes on to discuss, there may be some benefit to these superstitions, a la the placebo effect.  Basically, the placebo effect can be described as something like succumbing to the power of suggestion, or a self-fulfilling prophecy.  The idea is that if you tell a bunch of people that some experimental treatment is going to have an effect, like pain relief, then a certain number of those people are going to report feeling less pain, even if you don't give them the treatment.  As the ESPN article points out, there are some research articles out there that have looked at the placebo effect as it pertains to sports, and much like in biomedical studies, one can see that the placebo effect can yield better performance on both physical and mental performance, and may explain why many athletes believe in "lucky charms" or other superstitions.  Anyway, the article does a pretty good job of dealing with these aspects of the "magical bracelets" and other charms that seem to be so popular these days.  And apparently, a new episode of Outside the Lines will be featuring research done at the University of Wisconsin, Lacrosse, that determined how effective, or rather, ineffective the "power balance" bracelets are...




PS. If you read the article over at ESPN, you will see that the author makes mention of two articles pertaining to placebo effects and superstitions on performance.  However, the articles were not referenced, so I can only assume they are the ones that I linked to above (and here): one where cyclists were told that they were getting a carbohydrate supplement, and performed better than baseline, even though they only got a placebo, and another where "lucky" totems increased participants' performance on puzzles and memory games (as well as on 1 meter golf putts).  While tracking those two down, I also found this one, which again used cyclists, and similarly showed that the placebo effect could improve performance, though the participants were told they were getting caffeine rather than carbohydrates.  And, of course, the interesting thing about this last study was that, not only was there a placebo effect, but the effect was correlated with the amount of caffeine that the participants were told they had received (i.e. telling someone they got a little bit of caffeine made them perform a little better, telling them they got a lot of caffeine made them perform a lot better, even though neither group got any caffeine).


Clark VR, Hopkins WG, Hawley JA, & Burke LM (2000). Placebo effect of carbohydrate feedings during a 40-km cycling time trial. Medicine and science in sports and exercise, 32 (9), 1642-7 PMID: 10994918

Damisch L, Stoberock B, & Mussweiler T (2010). Keep your fingers crossed!: how superstition improves performance. Psychological science : a journal of the American Psychological Society / APS, 21 (7), 1014-20 PMID: 20511389

Beedie CJ, Stuart EM, Coleman DA, & Foad AJ (2006). Placebo effects of caffeine on cycling performance. Medicine and science in sports and exercise, 38 (12), 2159-64 PMID: 17146324

More Halloween Stuff

So, I know it's a day late, but I came across this post over at Discover magazine listing some of the more unusual, spooky reports to be found on the National Center for Biotechnology Information (NCBI) research search engine.  Like the "haunted" scrotum pictured to the right...