Psychological differentiation, as measured by field independence, is studied in relationship to cerebral hemispheric differentiation as assessed through dichotic listening and spatial task performance. Predictions regarding right-hemisphere functions and field independence were confirmed. More differentiated versus less differentiated right-hemisphere superiorities are distinguished and discussed in light of the field-dependence construct. The dimension of integration, characteristic of increasing differentiation, frames the prediction that field independents are better able to utilize the right hemisphere on typically left-hemisphere tasks. The results are discussed in relationship to the potential role of cerebral mechanisms underlying different defensive styles, and in regard to the neurophychological search for covariance between psychological and neurophysiological parameters.