The Association between Handedness, Brain Asymmetries, and Corpus Callosum Size in Chimpanzees (Pan troglodytes)

• Published in: Cerebral cortex (New York, N.Y. 1991) Vol. 17; no. 8; pp. 1757 - 1765
• Main Authors: Hopkins, William D., Dunham, Leslie, Cantalupo, Claudio, Taglialatela, Jared
• Format: Journal Article
• Language: English
• Published: United States Oxford University Press 01.08.2007; Oxford Publishing Limited (England)
• Subjects: Aging - physiology; Animals; Brain - anatomy & histology; Brain - physiology; brain asymmetry; Cerebral Cortex - anatomy & histology; Cerebral Cortex - physiology; chimpanzees; corpus callosum; Corpus Callosum - anatomy & histology; Corpus Callosum - physiology; Data Interpretation, Statistical; Feeding Behavior - physiology; Female; Functional Laterality - physiology; Gestures; handedness; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Organ Size - physiology; Pan troglodytes; Sex Characteristics; chimpanzees; corpus callosum; brain asymmetry; handedness
• ISSN: 1047-3211; 1460-2199
• DOI: 10.1093/cercor/bhl086

It has been suggested from studies in human subjects that sex, handedness, and brain asymmetries influence variation in corpus callosum (CC) size and these differences reflect the degree of connectivity between homotopic regions of the left and right cerebral hemispheres. Here we report that handedness is associated with variation in the size of the CC in chimpanzees. We further report that variation in brain asymmetries in a cortical region homologous to Broca's area is associated with the size of the CC but differs for right- and left-handed individuals. Collectively, the results suggest that individual differences in functional and neuroanatomical asymmetries are associated with CC variation not just in humans but also in chimpanzees and therefore may reflect a common neural basis for laterality in these 2 species.