 Neuropsychology

Neuropsychology studies relationships between brain function and cognition or behavior, including patterns of impairment and preservation after brain lesions. A task comparison can reveal a selective difficulty rather than a uniform loss of all abilities. Double dissociations strengthen the distinction between processes, but task demands, lesion extent and connected-system effects still matter. The classic amnesia studies illustrate how preserved abilities can be as informative as impaired ones. ^[ref]