When an athlete has suffered a concussion, the best medical advice is to rest, completely. No television, no reading, no bright lights, sometimes for two weeks or more. New research at SMU, however, shows that even after a few days, some basic cognitive tasks can get patients back on track. The study used heart rates and the parasympathetic nervous system to show that the cognitive task was helpful for some concussed patients. There is a connection between concussion and heart rate variability and the study looked at that as an indicator of brain recovery.
The scientists also point out that there is very little research being done on concussion recovery, especially when it’s connected to heart rate variability. Patients who have suffered a concussion often have a very low rate of variable heart rhythms. Healthy patients have a higher rate of change in their heart rhythm. In the study, they showed that the cognitive tasks, which were very simple, requiring only that the patient indicate when a letter they were shown was repeated on a screen, corresponded with better heart rate variability. This variability is a sign that the parasympathetic nervous system is engaged and that is a positive sign after a head injury.