Opposite turning behavior in right-handers and non-right-handers suggests a link between handedness and cerebral dopamine asymmetries.
The strong right hand preference in humans remains a riddle; no lateralized behavior other than fine finger dexterity relates to it. The relation between handedness and language dominance may be far weaker than currently judged; after all, both right-handers and non-right-handers utilize the left brain for speech. There is, however, a lateralized motor preference in animals, turning behavior, that is strongly associated with hemispheric dopamine (DA) asymmetries. Turning consistently occurs towards the side with less DA. The authors tested 69 right-handers and 24 non-right-handers with a device recording spontaneous turning behavior for 20 hr within 3 days. Findings indicate that right-handers preferred left-sided turning and non-right-handers preferred right-sided turning. This result suggests a link between handedness and DA asymmetries.
Mohr
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C
Department of Rehabilitation, University Hospital Geneva, Geneva, Switzerland. christine.mohr@hcuge.ch
Landis
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T
Bracha
H S
HS
Brugger
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P
D000328:Adult; D000704:Analysis of Variance; D004292:Dominance, Cerebral / Q000502:physiology*; D004298:Dopamine / Q000378:metabolism*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D009949:Orientation / Q000502:physiology*; D012016:Reference Values; D012737:Sex Factors; D013647:Task Performance and Analysis
D004298:Dopamine