SAN ANTONIO – Kimberley Phillips, associate professor of psychology at Trinity University, has received a $500,000 grant from the National Institutes of Health (NIH) to study the mechanisms that influence corpus callosum size in both chimpanzees and capuchin monkeys. Phillips received the grant in June for the research project, which will run for three years.

The overall project will look at the organization of the corpus callosum, which is the major white matter structure that connects the two cerebral hemispheres in the brain. Although chimpanzees and capuchins are diverse species, they share many similarities. Both use tools in the wild, have a high level of social cognition, and have large brains for their body size.

According to Phillips, the corpus callosum is believed to be fundamentally important to the emergence of higher cognitive functions in the brain. Differences in size of the corpus callosum have been linked to several neuropsychiatric and neurodevelopmental disorders such as schizophrenia and autism spectrum disorder. For her research, Phillips intends to further understand how size and shape differences in the corpus callosum are influenced by behavior, gender, and hand preference on complex tasks.

The innovative study will combine several strategies to gather information about brain organization and development including noninvasive imaging of the animals. Phillips is on the forefront of researchers utilizing magnetic resonance imaging (MRI) and diffusion tensor imaging (DTI) to study brain structures in primates.

In addition to digital imaging, Phillips will conduct behavioral studies of the primates using motor skill tasks and will look at the histological organization of the corpus callosum by gathering post mortem samples on animals that died naturally.

To help with the three components of the study, Phillips' research team will initially include four Trinity students. The students, all juniors, come from different majors: biology, chemistry, psychology, and neuroscience.

Research on the capuchin monkeys will take place mainly at the Southwest National Primate Research Center in San Antonio. Research on the chimpanzees will be conducted at Emory University's Yerkes National Primate Research Center in Atlanta, Ga.