This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. This year, studies in our laboratory focused on the in vivo and post-mortem analysis of the volume and lateralization of the planum temporale (PT) (the homolog to Wernicke's area) in chimpanzees. We found that the PT as measured from magnetic resonance images corresponds well to the cytoarchitectural distribution of Brodmann's area 22 (BA22). At both the gross anatomical and cellular levels of analysis, significant population-level leftward asymmetries were found in the chimpanzees. We further found that variation in asymmetries in the PT were associated with handedness for gestural communication but not other manual actions, suggesting that it has a functional role in communication.