Sex Differences in Familial Correlations for Visual and Kinesthetic Aftereffects

72 subjects from 16 families performed a visual and kinesthetic aftereffect task where data were also obtained on the pretest variability and on the adjustment times. Considerable sex differences were found, such that for mothers pretest variability correlated positively with magnitude of kinesthetic and negatively with magnitude of visual aftereffect. Daughters showed more pretest variability on both tasks and much larger individual differences on the visual task than sons. These sex differences complicate any attempt at genetic analysis. However, there was some indication of X-linked inheritance in males for magnitude aftereffect and of autosomal inheritance of visual adjustment time in females.