title: Effects of handedness on tactile temporal order judgment.
abstract: 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.
authors.affiliation: Department of Physiology, Juntendo University School of Medicine, Tokyo 113-8421, Japan. m-wada@med.juntedo.ac.jp
authors.forename: Makoto
authors.initials: M
authors.lastname: Wada
authors.forename: Shinya
authors.initials: S
authors.lastname: Yamamoto
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kitazawa
mesh_terms: 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*