Effects of handedness on tactile temporal order judgment.
We examined effects of handedness on the judgment of temporal order of successive taps delivered to both hands. When the subjects' arms were uncrossed, the temporal resolution (84% correct responses) of right-handed subjects (52 +/- 4 ms, n = 16) was significantly better than that of left-handed subjects (83 +/- 9 ms, n = 16). When their arms were crossed, both groups tended to invert their judgment to a similar extent at intervals as long as 200-300 ms. In the arms crossed condition, right handed subjects inverted their judgment more often in response to left-hand-first stimuli than to right-hand-first stimuli, whereas left-handed subjects did not show the same asymmetry. We infer that hemispheric lateralization, which is generally stronger in right- than in left-handed subjects, contributes to the relatively better temporal resolution of right-handed subjects in the uncrossed condition, as well as to the asymmetric effect of stimulation order in the crossed condition.
Wada
Makoto
M
Department of Physiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan. m-wada@med.juntedo.ac.jp
Yamamoto
Shinya
S
Kitazawa
Shigeru
S
D000293:Adolescent; D000328:Adult; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006225:Hand / Q000502:physiology; D006801:Humans; D007600:Judgment / Q000502:physiology*; D008297:Male; D016011:Normal Distribution; D010470:Perceptual Masking; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D013997:Time Factors; D013998:Time Perception; D014110:Touch / Q000502:physiology*