FRIDAY, Aug. 23 (HealthDay News) -- Concussion patients have
irregular brain activity within the first 24 hours after their
injury but increased levels of brain activity a few weeks later,
which suggests that the brain may compensate for the injury during
recovery, a new study reports.
Researchers used functional MRI to study the recovery of 12 high
school football players with concussion and compared them to 12
uninjured teammates. The concussed players underwent brain scans at
13 hours and again seven weeks after their head injury, and the
uninjured players had brain scans at the same time.
At 13 hours, the concussed athletes had typical symptoms such as
decreased reaction time and reduced mental abilities. Their brain
scans revealed decreased activity in certain areas of the right
hemisphere of the brain. This suggests that their reduced mental
abilities may be related to underactivation of attentional brain
circuits, according to the researchers.
At seven weeks, the concussed players showed improvement in
their mental abilities and normal reaction time. Brain scans at
that time revealed that the concussed athletes had more activation
in the brain's attentional circuits than the uninjured players.
"This hyperactivation may represent a compensatory brain
response that mediates recovery," study lead author Thomas Hammeke,
a professor of psychiatry and behavioral medicine at the Medical
College of Wisconsin, said in a college news release. "This is the
first study to demonstrate that reversal in activation patterns,
and that reversal matches the progression of symptoms from the time
of the injury through clinical recovery."
The study appears in the September issue of the
Journal of the International Neuropsychological Society.
"Deciding when a concussed player should return to the playing
field is currently an inexact science," study senior author Dr.
Stephen Rao, director of the Schey Center for Cognitive
Neuroimaging at the Cleveland Clinic, said in the news release.
"Measuring changes in brain activity during the acute recovery
period can provide a scientific basis for making this critical
The American Academy of Family Physicians has more about