The effect of subconcussive blows on fine motor control

Concussion has been shown to cause immediate impairment in motor control. However, the effect of subconcussive blows is much more controversial. The clinically accepted recovery time from concussion is 7-10 days. However, recent studies involving EEG and complex motor tasks have revealed deficits up to 12 years post injury. Several studies have shown cognitive deficits associated with subconcussive blows while other studies have shown there are no ill effects. Few studies have examined the effect of subconcussive blows on motor function. PURPOSE: To further elucidate the effect of subconcussive blows on fine motor control. METHODS: Twenty athletes (age 20.7 ?? 2.76) and twenty non-athletes (age 21.5 ?? 2.26) with no history of concussion or contact sports, were recruited from NCAA Division-I sports teams, university club teams, and student population. All subjects completed a Purdue pegboard task, finger tapping task and an isometric force control task. Group differences in test performance were assessed using a t-test and a 3-way ANOVA with repeated measures. RESULTS: Data analysis revealed differences in between athletes and non-athletes in the finger tapping test. Non-athletes 2nd highest, 3rd highest, and average tapping scores were higher than those of athletes (p=.023, p=.008, and p=.019 respectively). Three way ANOVA with repeated measures revealed that non-athletes outperformed athletes at 2 levels of visual gain, 128 and 512 pixels/N (p=.045 and p=.009 respectively). No other significant between group???s differences were found. CONCLUSION: There are differences in fine motor control between athletes and non-athletes. Non-athletes displayed better finger quickness and slightly better isometric force control, outperforming athletes on the tapping test and isometric force control test respectively. There was no difference in finger dexterity as performances on the Purdue peg board test were equal. Athletes are at higher risk for head injury than non-athletes and several of these athletes may have sustained a concussion and not reported it. Finger speed and isometric force control may be more affected than manual dexterity or perhaps those tasks were simply more difficult. Further study involving data collected from athletes with and without history of concussion is necessary to further elucidate the effects of subconcussive blows on fine motor control