Cerebral asymmetries for language: evidence for structural-behavioral correlations.
The current investigation tested 20 male right-handers in 5 divided visual field lexical tasks. Asymmetries in Heschl's gyrus, planum temporale, and planum parietale were measured using structural magnetic resonance imaging. Composite task asymmetries were positively correlated with asymmetry of the planum temporale only. There was also an association between the consistency of anatomical and behavioral asymmetries: Individuals who departed the most from the modal pattern of cortical asymmetry across regions also tended to show the greatest variability in asymmetry across tasks. Hence, individual differences in language laterality tasks may be affected by variation in asymmetry of posterior language structures. Additionally, when typical anatomical asymmetries fail to co-occur, there may be a less strictly regulated distribution of function across hemispheres.
Chiarello
Christine
C
Department of Psychology, University of California, Riverside, CA 92521, USA. christine.chiarello@ucr.edu
Kacinik
Natalie
N
Manowitz
Brian
B
Otto
Ronald
R
Leonard
Christiana
C
D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology*; D004193:Discrimination Learning / Q000502:physiology; D004292:Dominance, Cerebral / Q000502:physiology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D009415:Nerve Net / Q000502:physiology; D010296:Parietal Lobe / Q000502:physiology; D011932:Reading; D012016:Reference Values; D012660:Semantics; D013223:Statistics as Topic; D013702:Temporal Lobe / Q000502:physiology; D014794:Visual Fields / Q000502:physiology