Recent neuroscientific and clinical efforts have resulted in significant advances in understanding the human brain’s functional organization. In particular, the advent and widespread application of fMRI by neuroscientists has added significantly to our understanding of the relationship between localized brain activity and cognitive function. Using fMRI, cognitive neuroscientists have confirmed some previous findings based on lesion studies and neurosurgical explorations in awake patients. For example, fMRI has confirmed left hemisphere language dominance in most individuals and has demonstrated the importance of long-recognized areas in the frontal (Broca’s) and temporal (Wernicke’s) cortices for speech and language. These convergent findings lend support to the large amount of neuroscientific work being published based on fMRI and other mapping techniques, but there are still many outstanding questions even regarding such extensively studied processes as motor function.