NASCAR Concussions II: A Screening Test to Avoid Relying Entirely on the Driver

I was lucky enough to speak with Dr. Mark Lovell, an innovator in neurocognitive testing inbetween talks at a conference he was attending.  (Neurocognitive, incidentally, describes those thinking functions that are closely linked to particular areas of the brain.  We’re talking about things like attention, memory, speaking and understanding language, solving problems, and making decisions.)  Dr. Lovell was the founding director of the University of Pittsburgh’s Medical Center’s Sports Medicine Concussion Program and has published over a hundred journal articles and authored or co-authored nine textbooks about sports-related concussions.

Dr. Lovell came to my attention as the developer of the ImPACT (Immediate Post-Concussion Assessment Testing) test, which was one of the tools used to evaluate Dale Earnhardt, Jr.’s concussion.  Given that he is right up the road in Pittsburgh, I thought I’d spend a little time looking into exactly what the test is and whether it’s a viable alternative for NASCAR to use in screening drivers for concussion.

As I mentioned in my last post, physical damage to the brain can be detected by techniques like magnetic resonance imaging; however, even if the physical structure is intact, the brain works primarily on electrical and chemical signals – and we don’t have a way to simply look into a person’s head and verify that all the neurons are sending and receiving signals correctly.

Lovell wanted to make clear that concussions are a rapidly evolving field of research, noting that “90 percent of everything we know about concussion has been learned in the last ten years”.   Ten years ago, no one thought a concussion was a big deal.  Getting your “bell rung” was part of sports like football, hockey and boxing.  We’re learning now — especially from long-term studies of football and hockey players) that even a “mild” concussion in which you don’t lose consciousness can have short- and long-term results.

Here’s what the ImPACT test looks like:  You sit in front of a computer terminal for about twenty minutes and respond to a series of fast-moving activities.   For example, you’re given twelve target words to memorize – you get to see the words for 750 milliseconds each — and you get to see each word twice.  You are then presented with twenty four words, twelve of which are the ones you saw already and twelve of which are similar in some way to the words you saw.  For example, you might be shown the word “ice” as one of the ones to remember and “snow” as a non-target word.    A box comes up and asks “was pencil one of the words displayed?” and you click yes or no.  There are similar exercises using abstract designs, letters, colors, and symbols.  Each exercise tests one (or more) neurocognitive function.

It’s not easy.  In fact, when you’re done, you feel a little like someone has been throwing things at your brain.  The test requires you to multi-task and if you took the time to try to think about how to cheat, it would be obvious that you weren’t giving it your best try.

Lovell emphasizes that a complete evaluation for concussion requires many parts:  The process requires collecting demographic information and a health history survey, including any history of previous concussions.  If you’ve had mental health issues or are taking medications, that has to be factored in as well.  A full description of the injury also is usually included.  Assuming NASCAR adapted this as a standard test, this would all be on file or easily available.

The ImPACT test looks at six distinct elements:

  • Verbal memory (your ability to pay attention, learning and memory relating to verbal things like words, symbols and letters)
  • Visual memory (visual attention and scanning, learning and memory related to visual processes)
  • Visual motor speed (visual processing, learning and memory, and visual-motor response speed)
  • Reaction time (how fast you can respond to something)
  • Impulse control (this is actually a way of measuring the uncertainties inherent in the testing)
  • Symptom score (this measures the presence and severity of 22 symptoms, ranging from sleeping to balance to irritability to fogginess).  This is really the only area of the test in which a driver could try to hide evidence of a concussion.

Dr. Lovell recommends that athletes do a “baseline test” prior to engaging in their sport.  For NASCAR, that would be at the start of every season.  Although the test is still useful without a baseline, having the pre-test allows you to compare a driver’s current state with his previous state and reduces uncertainties that might be caused by things specific to an individual.   Over many years of testing athletes at all levels, the ImPACT people have collected scores for people in different age groups, genders and populations (i.e. athletes vs. us couch potatoes), so even without a baseline, a doctor would have some reference point for how well you ought to score by comparing your score with a typical score of someone similar to you.

One of the challenges of concussion is that it’s a type of injury in which the patient may try to hide the symptoms from the doctor.  Dr. Lovell designed the ImPACT test to help diagnose concussion, even when the subject is reluctant to admit that he or she is exhibiting symptoms.  Trying to purposely score poorly on the test works against the athlete (a bad score makes it more likely you’ll be sat down), so the athlete is motivated to do their best.

Anyone developing a test (whether it be for education or medicine) has to worry about people who try to get around the test’s purpose.  What was most impressive to me in reading the research papers about the ImPACT test is that the developers have come up with ways to tell when people are trying to outwit the test.  Dr. Lovell laughed when he told me that some athletes “sandbag” during their baseline testing, thinking that if they have a lower baseline score, they can get hurt and it won’t be detected.  The test developers have found ways to measure whether someone was trying, for example, to be more accurate by taking the test more slowly, or to complete the test quickly without worrying about being correct.  The test is not only measuring neurocognitive function, it’s measuring whether you’re taking the test to the best of your ability.

Your score on the ImPACT test isn’t a yes/no measure of whether you have a concussion.  Concussion is a subtle enough injury that you still need evaluation by an experienced professional; however, Dr. Lovell believes that the ImPACT test is a good way to screen athletes to determine whether additional medical evaluation is necessary.

Your score on the ImPACT test also gives the diagnosing doctor some help in predicting time to recovery.  The team has developed a cut-off score that broadly predicts whether recovery time will be less than or more than two weeks.  It’s not exact, of course.  Dr. Lovell emphasizes that one of the challenges understanding and treating concussions is that every individual is different.  Most will fall into a “normal” range, but there are always exceptions at both ends of that range.  Repeat testing helps the doctor measure how well the patient is progressing because there can still be neurocognitive impairment well after the obvious symptoms have gone away.

ImPACT is a twenty-minute test administered on a computer.  A system for administering the test could be brought to any race (it’s much more portable than an engine dyno!) and, given that it takes just 20 minutes to complete, seems like a very easy to implement screening tool after any hard impact.  Again, Dr. Lovell would be the first to emphasize that you don’t just take the test and know that you do/don’t have a concussion; however, NASCAR could easily require any driver involved in a crash to do a quick assessment to determine whether they should be seen by a doctor for further followup.

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