Physiological correlates of extreme intellectual precocity.

Among extremely mathematically and/or verbally precocious students (top 1 in 10,000 in such reasoning ability), the following three physiological characteristics were found at high frequencies: left- or mixed-handedness, asthma and other allergies, and myopia. The first two of these may reflect the effects of a common influence (testosterone) on the nervous and immune systems during fetal development. Moreover, our results suggest that such highly able students may exhibit bihemispheric representation of cognitive functions. These results may bear on the etiology of intellectual talent.