title: Nonverbal intelligence, familial sinistrality and left-handedness.
abstract: The interrelations among Geschwind scores, familial sinistrality, and nonverbal intelligence were studies in left-handed males and females. Nonverbal intelligence (spatial reasoning) was assessed by Cattle's Culture Fair Intelligence Test. Hand preference was assessed by the Edinburgh Handedness Inventory, and a laterality score (Geschwind score) was calculated for each subject. The mental ability for spatial reasoning was found to be related to the degree of the left-hand preference in conjunction with familial sinistrality. Moderate left-handedness was found to be advantageous for nonverbal intelligence. It was concluded that cognitive and motor functions are interrelated systems; the efficiency of the spatial reasoning would depend on the degree and developmental level of cerebral lateralization.
authors.affiliation: Atatürk University, Medical Faculty, Institute of Physiology, Erzurum, Turkey.
authors.forename: U
authors.initials: U
authors.lastname: Tan
mesh_terms: D000328:Adult; D005190:Family; D005260:Female; D007839:Functional Laterality; D006801:Humans; D007360:Intelligence; D007361:Intelligence Tests; D008297:Male; D011597:Psychomotor Performance; D012737:Sex Factors; D014421:Turkey