Extracting brain connectivity

Abstract In the late nineteenth century the early investigations of brain function were dominated by the concept of functional segregation. This approach was driven largely by the data available to scientists of that era. Patients with circumscribed lesions were found who were impaired in one particular ability while other abilities remained largely intact. Indeed, descriptions of patients with different kinds of aphasia (an impairment of the ability to use or comprehend words), made at this time, have left a permanent legacy in the contrast between Broca’s and Wernicke’s aphasia. These syndromes were thought to result from damage to anterior or posterior regions of the left hemisphere respectively.