For instance, high school
athletes who were identified as having postconcussion mental status changes on sideline assessment, such as retrograde amnesia and confusion, had impaired memory 36 hours (d=.74, medium-large effect size), 4 days (d=.69, medium-large effect size), and 7 days (d=.34, small effect size) postinjury compared with baseline. 26 Impaired cognitive function was found in both American and Australian professional footballers with postconcussion symptoms in 2 studies. 20 and 23 For example, the cognitive performance of a symptomatic group of concussed professional Australian footballers declined at the postconcussion assessment on computerized tests of simple, choice, and complex reaction times compared with the asymptomatic and control groups. 20 The magnitude of these changes, selleck chemicals llc expressed in within-subjects SD, was large (simple reaction speed, −.86; choice reaction speed, −.60; complex reaction speed, −.61). The most common symptom experienced in the symptomatic group was headache. Of note, pain (eg, chronic pain) has been associated with lower cognitive function. 28 The use of Tanespimycin research buy an injured control group rather than an uninjured one might be useful in observing
whether concussion-related pain affects cognitive function differently than pain from other causes such as orthopedic injuries. One study17 found that self-reported postconcussion symptoms did not predict poor performance on neuropsychological testing in any high school or college athlete when compared with noninjured controls. However, specific symptoms were not reported. It might be the case that some symptoms, such as cognitive symptoms, are more related
to cognitive performance deficits than others such as fatigue. Four studies17, 18, 23, 24 and 26 suggest that high school athletes (ie, 13–18y of age) appear to take longer to recover cognitive function compared with older and more experienced athletes (ie, collegiate and professional athletes). To illustrate, high school athletes (aged ∼16y) took up not to 21 days to return to baseline levels for reaction time after concussion18 and had prolonged memory dysfunction compared with college athletes (aged ∼20y).17 A comparison of these groups at 3 days postinjury indicated significantly poorer performance for the high school group for both the Hopkins Verbal Learning Test total (P<.005) and the Hopkins Verbal Learning Test delay (P<.02). However, this performance difference was no longer evident at day 5 or day 7. 17 Professional American footballers (aged ∼26y) returned to baseline performance (verbal memory, reaction time) in 1 week, with most having normal performance within 2 days postinjury; however, high school athletes (aged ∼16y) had a slower recovery. 24 When tested within 7 days of injury, high school athletes had a drop of approximately 0.4 SD units in verbal memory and a .