The relationship of latency characteristics of the Hoffmann reflex from the right and left thenar muscles to serum testosterone levels in right-handed male and female subjects.
The latency characteristics of the Hoffmann reflex from the right and left thenar muscles were analyzed in right-handed young men and women relative to serum testosterone levels. There was no correlation between the H-reflex latencies and serum testosterone levels in the female subjects. In the male subjects, the H-reflex latencies from the right and left sides were found to be negatively linearly related to the serum testosterone levels. The right minus left latencies were found to be inversely correlated with serum testosterone levels in women; there was no correlation between these variables in men. It was also established that the right-left differences in the H-reflex latencies were directly related to the degree of the right-hand preference in the female subjects. It was concluded that testosterone may, at least, contribute to the spinal-motor lateralization in women, but not in men. The results were also discussed with regard to the testosterone hypothesis of cerebral lateralization, sex-related differences, hand preference, hand skill, and intelligence.
Tan
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Atatürk University, Medical Faculty, Institute of Physiology, Erzurum, Turkey.
D000328:Adult; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006181:H-Reflex / Q000502:physiology*; D006225:Hand / Q000502:physiology*; D006801:Humans; D008297:Male; D009132:Muscles / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013739:Testosterone / Q000097:blood*
D013739:Testosterone