Open Access Dissertation
Date of Award
Conclusions in the literature regarding the relationship between a lateralized bias in the processing of information and individual differences (e.g., biological sex, gender identity, ability, personality) are inconsistent. We compared two different measures of laterality: dichotic listening and lateralized semantic priming and their relation to sex, verbal and visual-spatial ability, gender identity, and personality.
Eighty-nine adults (44 women, 45 men) were administered the Wechsler Abbreviated Scale of Intelligence, Bem Sex Role Inventory, and Big Five Inventory in addition to a dichotic listening task and a lateralized semantic priming task that compared ipsilateral and contralateral priming in order to determine the role of interhemispheric transfer. Two stimulus onset asynchronies (SOA; 50 ms and 400 ms) and two levels of association strength (high and neutral) between the prime and the target words were used in the priming task.
Ipsilateral prime-target reaction times were faster than contralateral prime-target presentations, while contralateral presentations resulted in greater semantic priming, suggesting that the time required for interhemispheric transfer allows for greater semantic activation. Further, greater association strength increased semantic priming only at the longer SOA and only the shorter SOA correlated with the dichotic listening lateralization index. Individual differences were unrelated to the lateralized indices.
The findings suggest that both dichotic listening and the shorter SOA condition measured automatic or perceptual lateralization whereas the longer SOA condition measured post-lexical lateralization of word meaning. Future research focusing on individual differences in the lateralization of information processing should employ and contrast different lateralization measures.
Van Dyke, Sarah Ann, "Individual differences in hemispheric lateralization of language processing" (2011). Wayne State University Dissertations. Paper 361.