title: Brain structure in young and old East Asians and Westerners: comparisons of structural volume and cortical thickness.
abstract: There is an emergent literature suggesting that East Asians and Westerners differ in cognitive processes because of cultural biases to process information holistically (East Asians) or analytically (Westerners). To evaluate the possibility that such differences are accompanied by differences in brain structure, we conducted a large comparative study on cognitively matched young and old adults from two cultural/ethnic groups--Chinese Singaporeans and non-Asian Americans--that involved a total of 140 persons. Young predominantly White American adults were found to have higher cortical thickness in frontal, parietal, and medial-temporal polymodal association areas in both hemispheres. These findings were replicated using voxel-based morphometry applied to the same data set. Differences in cortical thickness observed between young volunteers were not significant in older subjects as a whole. However, group differences were evident when high-performing old were compared. Although the observed differences in gray matter may be rooted in strategic differences in cognition arising from ethnic/cultural differences, alternative explanations involving genetic heritage and environmental factors are also considered.
authors.affiliation: Cognitive Neuroscience Laboratory, Duke-NUS Graduate Medical School, College Road, 7 Hospital Drive, Block B, 169857 Singapore, Singapore. michael.chee@dukenus.edu.sg
authors.forename: Michael Wei Liang
authors.initials: MW
authors.lastname: Chee
authors.forename: Hui
authors.initials: H
authors.lastname: Zheng
authors.forename: Joshua Oon Soo
authors.initials: JO
authors.lastname: Goh
authors.forename: Denise
authors.initials: D
authors.lastname: Park
authors.forename: Bradley P
authors.initials: BP
authors.lastname: Sutton
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology*; D044466:Asian People; D001921:Brain / Q000033:anatomy & histology / Q000502:physiology; D002540:Cerebral Cortex / Q000033:anatomy & histology* / Q000502:physiology; D002641:Chicago; D003431:Cross-Cultural Comparison; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D009929:Organ Size; D012016:Reference Values; D012737:Sex Factors; D012846:Singapore; D044465:White People; D055815:Young Adult