[Latent handedness and individual hemisphericity]

Area of Science:

• Psychology
• Neuroscience
• Cognitive Science

Background:

• Latent handedness, as defined by Luria (1966), explores subtle variations in hand preference.
• Individual hemisphericity refers to the dominance of one brain hemisphere for specific functions.
• Previous research suggests potential links between handedness, hemisphericity, and cognitive styles.

Purpose of the Study:

• To investigate the relationship between latent handedness and individual hemisphericity.
• To evaluate the utility of the Hemisphericity Test (HT) and Cognitive Mode Questionnaire (CMQ) in assessing these constructs.
• To explore potential sex differences in these relationships.

Main Methods:

• 125 undergraduate students (69 males, 56 females) participated.
• Latent handedness was assessed using criteria including the arm-folding subtest.
• Individual hemisphericity was measured using a version of the Hemisphericity Test (HT) and the Cognitive Mode Questionnaire (CMQ).

Main Results:

• In males, the arm-folding subtest showed a significant correlation with HT scores.
• Male subjects with right-arm-uppermost preference (R group) showed a greater preference for verbal stimuli compared to the left-arm-uppermost group (L group).
• HT scores significantly differed between groups classified by CMQ, indicating a link between CMQ and hemisphericity, but not latent handedness subtests.

Conclusions:

• The arm-folding subtest appears to reflect individual hemisphericity in males, supporting Sakano's hypothesis.
• The CMQ is related to individual hemisphericity, but latent handedness subtests did not show this association.
• The absence of significant findings in females suggests potential sex-based differences in cerebral asymmetry influencing these relationships.