Lifting The Fog Of Sports Concussions


A concussion, clinically known as a Mild Traumatic Brain Injury (MTBI), is one of the most common yet least understood sports injuries.  According to the Centers for Disease Control, there are as many as 300,000 sports and recreation-related concussions each year in the U.S., yet the diagnosis, immediate treatment and long-term effects are still a mystery to most coaches, parents and even some clinicians.  

The injury can be deceiving as there is rarely any obvious signs of trauma.  If the head is not bleeding and the player either does not lose consciouness or regains it after a brief lapse, the potential damage is hidden and the usual "tough guy" mentality is to "shake it off" and get back in the game.


Leigh Steinberg, agent and representative to some of the top professional athletes in the world (including NFL QBs Ben Roethlisberger and Matt Leinart), is tired of this ignorance and attitude.  "My clients, from the day they played Pop Warner football, are taught to believe ignoring pain, playing with pain and being part of the playing unit was the most important value," Steinberg said, "I was terrified at the understanding of how tender and narrow that bond was between cognition and consciousness and dementia and confusion".  Which is why he was the keynote speaker at last week's "New Developments in Sports-Related Concussions" conference hosted by the University of Pittsburgh Medical College Sport Medicine Department in Pittsburgh. 

Leading researchers gathered to discuss the latest research on sports-related concussions, their diagnosis and treatment.  "There's been huge advancement in this area," said Dr. Micky Collins, the assistant director for the UPMC Sports Medicine Program. "We've learned more in the past five years than the previous 50 combined."


So, what is a concussion?  The CDC defines a concussion as "a complex pathophysiologic process affecting the brain, induced by traumatic biomechanical forces secondary to direct or indirect forces to the head."  Being a "mild" form of traumatic brain injury, it is generally believed that there is no actual structural damage to the brain from a concussion, but more a disruption in the biochemistry and electrical processes between neurons.  

The brain is surrounded by cerebrospinal fluid, which is supposed to provide some protection from minor blows to the head.  However, a harder hit can cause rotational forces that affect a wide area of the brain, but most importantly the mid-brain and the reticular activating system which may explain the loss of consciousness in some cases.  

For some athletes, the concussion symptoms take longer to disappear in what is known as post-concussion syndrome.  It is not known whether this is from some hidden structural damage or more permanent disruption to neuronal activity.  Repeated concussions over time can lead to a condition known as dementia pugilistica, with long-term impairments to speech, memory and mental processing.

After the initial concussion, returning to the field before symptoms clear raises the risk of second impact syndrome, which can cause more serious, long-term effects.  As part of their "Heads Up" concussion awareness campaign, the CDC offers this video story of Brandon Schultz, a high school football player, who was not properly diagnosed after an initial concussion and suffered a second hit the following week, which permanently changed his life.  Without some clinical help, the player, parents and coach can only rely on the lack of obvious symptoms before declaring a concussion "healed".  

However, making this "return to play" decision is now getting some help from some new post-concussion tests.  The first is a neurological skills test called ImPACT (Immediate Post-Concussion and Cognitive Testing) created by the same researchers at UPMC.  It is an online test given to athletes after a concussion to measure their performance in attention span, working memory, sustained and selective attention time, response variability, problem solving and reaction time.  Comparing a "concussed" athlete's performance on the test with a baseline measurement will help the physician decide if the brain has healed sufficiently.

However, Dr. Collins and his team wanted to add physiological data to the psychological testing to see if there was a match between brain activity, skill testing and reported symptoms after a concussion.  In a study released last year in the journal Neurosugery, they performed functional MRI (fMRI) brain imaging studies on 28 concussed high-school athletes while they performed certain working memory tasks to see if there was a significant link between performance on the tests and changes in brain activation.  They were tested about one week after injury and again after the normal clinical recovery period.

“In our study, using fMRI, we demonstrate that the functioning of a network of brain regions is significantly associated with both the severity of concussion symptoms and time to recover,” said Jamie Pardini, Ph.D., a neuropsychologist on the clinical and research staff of the UPMC concussion program and co-author of the study.  
 "We identified networks of brain regions where changes in functional activation were associated with performance on computerized neurocognitive testing and certain post-concussion symptoms,” Dr. Pardini added. "Also, our study confirms previous research suggesting that there are neurophysiological abnormalities that can be measured even after a seemingly mild concussion.” 

Putting better assessment tools in the hands of athletic trainers and coaches will provide evidence-based coaching decisions that are best for the athlete's health.  Better decisions will also ease the minds of parents knowing their child has fully recovered from their "invisible" injury.


ResearchBlogging.org

Lovell, M.R., Pardini, J.E., Welling, J., Collins, M.W., Bakal, J., Lazar, N., Roush, R., Eddy, W.F., Becker, J.T. (2007). FUNCTIONAL BRAIN ABNORMALITIES ARE RELATED TO CLINICAL RECOVERY AND TIME TO RETURN-TO-PLAY IN ATHLETES. Neurosurgery, 61(2), 352-360. DOI: 10.1227/01.NEU.0000279985.94168.7F

Sideline Raging Soccer Moms (and Dads!)

Visit any youth soccer field, baseball diamond, basketball court or football field and you will likely see them:  parents behaving badly.  Take a look at this Good Morning America report:

These are the extremes, but at most games, you can find at least one adult making comments at the referee, shouting at their child, or having a verbal exchange with another parent.  Thankfully, these parents represent only a small percentage of those attending the game.  Does that mean the others don't become upset at something during the game?  Usually not, as there are lots of opportunities to dispute a bad call or observe rough play or react to one of these loud parents.  

The difference is in our basic personality psyche, according to Jay Goldstein, a kinesiology doctoral student at the University of Maryland School of Public Health.  His thesis, recently published in the Journal of Applied Social Psychology (see reference below), hypothesized that a parent with "control-oriented" personality would react to events at a game more than a parent with an "autonomy-oriented" personality.

According to Goldstein, defending our ego is what usually gets us in trouble when we feel insulted or take something personally.  At youth sports games, we transfer this pride to our kids, so if someone threatens their success on the field, we often take it personally.  The control-oriented parent is more likely to react with a verbal or sometimes physical response, while an autonomy-oriented parent is better able to internalize and maintain their emotions.  This "control" vs. "autonomy" comparison has also been seen in research on "road rage", when drivers react violently to another driver's actions.

Goldstein and his team focused their research on suburban Washington soccer parents back in 2004.  They designed a survey for parents to fill out prior to watching a youth soccer game that would help categorize them as control or autonomy-oriented.  Immediately after the game ended, another survey was given to the parents that asked about any incidents during the game that made them angry on a scale of 1, slightly angry, to 7, furious.  They were also asked what action they took when they were angry.  Choices included "did nothing" to more aggressive acts like walking towards the field and/or yelling or confronting either the referee, their own child, or another player/parent.  53% of the 340 parents surveyed reported getting angry at something during the game, while about 40% reported doing something about their anger.

There was a direct and significant correlation between control-oriented parents, as identified in the pre-game survey, and the level of angry actions they took during the game.  Autonomy-oriented parents still got mad, but reported less aggressive reactions.  As Goldstein notes, “Regardless of their personality type, all parents were susceptible to becoming more aggressive as a result of viewing actions on the field as affronts to them or their kids.  However, that being said, it took autonomy-oriented parents longer to get there as compared to the control-oriented parents.”

So, now that we know the rather obvious conclusion that parents who yell at other motorists are also likely to yell at referees, what can we do about it?  Goldstein sees this study as a first step.  He hopes to study a wider cross-section of sports and socio-economic populations.  Many youth sports organizations require parents to sign a pre-season "reminder" code of conduct, but those are often forgotten in the heat of the battle on the field.  

Maybe by offering the same type of personality survey prior to the season, the "control-oriented" parents can be offered resources to help them manage their tempers and reactions during a game.  Since referees were the number one source of frustration reported by parents, two solutions are being explored by many organizations; more thorough referee training and quality control while also better training of parents on the rules of the game which often cause the confusion.

Sports contests will always be emotional, from kids' games all the way up to professionals.  Keeping the games in perspective and our reactions positive are tough things to do but when it comes to our kids, it is required.

ResearchBlogging.org

Goldstein, J.D., Iso-Ahola, S.E. (2008). Determinants of Parents' Sideline-Rage Emotions and Behaviors at Youth Soccer Games. Journal of Applied Social Psychology, 38(6), 1442-1462. DOI: 10.1111/j.1559-1816.2008.00355.x

Does Practice Make Perfect?


For years, sport science and motor control research has added support to the fundamental assertions that "practice makes perfect" and "repetition is the mother of habit".  Shooting 100 free throws, kicking 100 balls on goal or fielding 100 ground balls must certainly build the type of motor programs in the brain that will only help make the 101st play during the game.  K. Anders Ericsson, the "expert on experts", has defined the minimum amount of "deliberate practice" necessary to raise any novice to the level of expert as 10 years or 10,000 hours.

However, many questions still exist as to exactly how we learn these skills.  What changes happen in our brains when we teach ourselves a new task?  What is the most effective and efficient way to master a skill?  Do we have to be actually performing the skill to learn it, or could we just watch and learn? 


Then, once we have learned a new skill and can repeat it with good consistency, why can't we perform it perfectly every time?  Why can't we make every free throw, score with every shot on goal, and field each ground ball with no errors?  We would expect our brain to just be able to repeat this learned motor program with the same level of accuracy.

To answer these questions, we look at two recent studies.  The first, by a team at Dartmouth's Department of Psychological and Brain Sciences, led by Emily Cross, who is now a post-doc at Max Planck Institute for Cognitive and Brain Sciences in Leipzig, Germany, wanted to know if we need to physically perform a new task to learn it, or if merely observing others doing it would be enough. 

The "task" they chose was to learn new dance steps from a video game eerily similar to "Dance, Dance Revolution".  If you (or your kids) have never seen this game, its a video game that you actually get up off the couch and participate in, kind of like the Nintendo Wii.  In this game, a computer screen (or TV) shows you the dance moves and you have to imitate them on a plastic mat on the floor connected to the game.  If you make the right steps, timed to the music, you score higher.

Cross and the team "taught" their subjects in three groups.  The first group was able to view and practice the new routine.  The second group only was allowed to watch the new routine, but not physically practice it.  The third group was a control group that did not get any training at all.  The subjects were later scanned using functional magnetic resonance imaging (fMRI) while they watched the same routine they had either learned (actively or passively) or not seen (the control group).


As predicted, they found that the two trained groups showed common activity in the Action Observance Network (AON) in the brain (see image on left), a group of neural regions found mostly in the inferior parietal and premotor cortices of the brain (near the top of the head) responsible for motor skills and some memory functions.  In other words, whether they physically practised the new steps or just watched the new steps, the same areas of the brain were activated and their performance of the new steps were significantly similar.  The team put together a great video summarizing the experiment.  

One of the themes from this study is that, indeed, learning a motor skill takes place in the brain.  This may seem like an obvious statement, but its important to accept that the movements that our limbs make when performing a skill are controlled by the instructions provided from the brain.  So, what happens when the skill breaks down?  Why did the quarterback throw behind the receiver when we have seen him make that same pass accurately many times?  


To stay true to our theme, we have to blame the brain.  It may be more logical to point to a mechanical breakdown in the player's form or body movements, but the "set-up" for those movements starts with the mental preparation performed by the brain.


In the second study, electrical engineers at Stanford University took a look at these questions to try to identify where the inconsistencies of movement start.  They chose to focus on the "mental preparation" stage which occurs just before the actual movement.  During this stage, the brain plans the coordination and goal for the movement prior to initiating it.  The team designed a test where monkeys would reach for a green dot or a red dot.  If green, they were trained to reach slowly for the dot; if red, to reach quickly.  By monitoring the areas of the monkeys' brains through fMRI, they observed activity in the AON prior to the move and during the move.  


Over repeated trials, changes in reach speed were associated with changes in pre-movement activity.  So, instead of perfectly consistent reach times by the monkeys, they saw variation, like we might see when trying to throw strikes with a baseball many times in a row.  Their conclusion was that this planning activity in the brain does have an effect on the outcome of the activity.  Previously, research had focused only on breakdowns during the actual move and in the mechanics of muscles.  This study shows that the origin of the error may start earlier.


As electrical engineering Assistant Professor Krishna Shenoy stated, "the main reason you can't move the same way each and every time, such as swinging a golf club, is that your brain can't plan the swing the same way each time."  

Postdoctoral researcher and co-author Mark Churchland added, "The nervous system was not designed to do the same thing over and over again.  The nervous system was designed to be flexible. You typically find yourself doing things you've never done before." 
The Stanford team also has made a nice short video synopsis of their study.

Does practice make perfect?  First, we must define "practice".  We saw that it could be either active or passive.  Second, we know sports skills are never "perfect" all the time, and need to understand where the error starts before we can begin to fix it.

Why The Offsides Flag Has Been "Ruud" to Italy

Two Euro 2008 games and two questionable offsides calls against Italy, one on defense, the other on offense, are still being talked about this weekend. First, in the Netherlands opener, van Nistelrooy scores from an obvious offsides position... except for Panucci, who is lying on the ground next to the goal. In fact, UEFA had to defend their referee for a correct interpretation. The call that did not get an explanation was Luca Toni's offsides on a cross from Zambrotta in the Romania match, which disallowed a first half goal. The first call was deemed correct, the second one was a blatant error.

Calling offsides correctly is one of the most difficult officiating duties in sports. In fact, some have argued that it is nearly impossible given the limitations of the human eye and the number of objects that need to be tracked by one assistant referee. Back in 2004, Francisco Belda Maruenda, M.D. of Centro de Salud de Alquerías in Murcia, Spain, took a look at the eye movements necessary along with their associated durations to determine if it was a humanly possible task. Let's look at his logic.

First, some eye physiology definitions are needed:
Saccadic movements - when we shift our eyes' focus from one object to another, we are making a saccadic movement. As an assistant referee (AR) looks from the ball carrier to the last defender to the offensive players, he needs to make several saccadic movements to take in the whole scene.

Vergence movements - there are two types, convergence (changing gaze from objects far away to objects closer to you), and divergence (just the opposite, near to far).

Accomodation - to change the focus of the eye from far to near or near to far, the convexity of the retina lens needs to change.

All of these eye movements, saccadic, vergence and accomodations take time to accomplish. Let's see how Maruenda added these up for an offsides call:

- the AR needs to keep track of at least four objects, the ball, the last two defenders and the offensive receiver of the pass. There may also be more offensive players to track as well.
- to make saccadic movements from the first object to each of the remaining objects will take about 130ms for the first object and then another 10ms per object after that. With four objects to track, that would be a total of about 160ms.
- if some of the players are on the far side of the field and some on the near side, then a vergence movement and an accomodation would be required, taking an additional 360ms for the accomodation and 640ms for the far to near vergence movement.
- of course, the players are constantly moving during the play, so their position is changing rapidly. If the speed of an offensive player is assumed to be 7.14 m/s, then in 100ms, they will have moved 71cm. This movement could be the difference between an onside position and an offside position. See the diagrams below (taken directly from the article)

Top: No offside, players in correct position.








Bottom: 100 ms later (players' velocity 7.14 m/s), offsides











The conclusion then, is that the total time needed for the AR to focus on at least four different objects in sequential order and process their positions cognitively is beyond the 100ms that would be needed for an offensive player to move from an onside position when the ball is played to a perceived offsides position when the AR finally focuses on him.

There have been some responses to Maruenda's logic, mainly centered on the fact that ARs have long known they can't watch the ball and the last defender, so they instead listen for the sound of the ball being struck while staying focused on the line of defense. This method may be used, but the sound of the crowd, the muted sound of the boot on the ball and the slower speed of sound may also have an effect on this judgement.

There is technology being developed to make offsides calls with multiple cameras, etc., but FIFA is not in favor of taking the flag away from the AR yet, just as they are against obvious goal line technology to watch for goals. It appears the debates and arguments will live on for the near future.

ResearchBlogging.org

Belda Maruenda, F. (2004). Can the human eye detect an offside position during a football match?. BMJ, 329(7480), 1470-1472. DOI: 10.1136/bmj.329.7480.1470