Since 1966 Professor Passingham has conducted studies on the frontal lobes of non-human primates and of neurological patients. In 1988 he added studies of healthy human subjects using PET and in 1995 converted to fMRI. He has used TMS and rTMS to disrupt function in healthy human subjects.

The main topic of research has been decision making. This has involved not only studying the prefrontal cortex but also the premotor and supplementary motor cortex via which the prefrontal cortex gains access to the motor system. In the more recent studies using fMRI the work has turned from being concerned with the localization of particular cognitive operations to the way in which the system works as a whole. This has involved studying the interactions between different brain areas using structural equation modelling, correlations and the analysis of psychophysiological interactions using the regression slopes. Recent studies have concentrated in particular on how the instructions given to subjects influence the brain areas that are involved in task performance.

Professor Passingham read Psychology and Philosophy at Oxford, taking finals in 1964. He then did an MSc in Abnormal Psychology at the Institute of Psychiatry in London. He followed this with a Ph.D. at the Institute on frontal lobe function in non-human primates. He then returned to Oxford, first as a research associate, and in 1976 as a University Lecturer and Fellow of Wadham College. He was appointed to an ad hominem Readership in 1993. He became Professor of Cognitive Neuroscience in 1997. He is an Honorary Principal at the Wellcome Centre for NeuroImaging (London).