O Ardila | PubMed Health

PubMed1993

Handedness in native Amazonians.

A sample of 65 Tucano adolescents living in the Amazon region of Colombia were administered a 26-item handedness questionnaire. All subjects were right-handed. A factor analysis of the data indicated a factor structure rather different from that seen in North Americans, although both skilled and unskilled handedness factors were seen. Other factors related to specific tool use and to strength. These data indicate that positive reinforcement for right-hand use can modify patterns of handedness, and may well alter the relations among different items. The data suggest that hand preference can be modified through positive reinforcement at an appropriate age, and that hand preference is the precursor of skill differences rather than vice versa.

Adolescent↗

PubMed1989

Effects of cultural background and education on handedness.

A 5-item handedness questionnaire was given to 317 subjects in four different groups: (1) 51 Tucano (Amazonian jungle) adolescents (36 male, 15 female); (2) 66 Spanish-speaking adolescents (43 male, 23 female) with similar age and educational background to the Tucano group; (3) 100 urban subjects (50 male, 50 female) with a low educational level; and (4) 100 urban subjects (50 male, 50 female) with a high level of education. Hand preference scores were not affected by sex or educational level. The incidence of left-handedness was lower in the Tucano group than in the other groups, despite the fact that the Tucano culture is a highly permissive one. The two rural groups showed less extreme hand preferences than the urban groups, and the Tucano in particular were less likely to indicate extreme hand preferences on any of the items. These results indicate significant effects of culture and environment on declared hand preference, and may be pertinent to recent discussions of cerebral organization in illiterates.

Adolescent↗