University of Nottingham, Nottingham, United Kingdom
Neuropsychology is the study of behavioural and cognitive deficits in patients with brain lesions, comparing task performance between healthy controls and those with brain damage to infer the link between brain anatomy and behaviour. The discipline’s three most popular tools – association, dissociation, and double dissociation studies – have yielded a vast amount of valuable experimental and clinical insight for neuroscience’s understanding of the brain-behaviour connection. Here, specific contributions from each type of study are discussed in relation to the diagnosis and treatment of three neuropsychological impairments – Bálint’s syndrome, visual form agnosia, and aphasia. The inherent limitations of neuropsychology as a discipline are considered, including the problem of low generalizability, the debatable fractionation assumption, poor temporal resolution and its relative obsoleteness in comparison to contemporary brain imaging techniques. It is concluded that the combined approach of converging traditional neuropsychological techniques with modern neuroimaging methods, is most efficient at providing insight on brain function and localisation, leading to brain-behaviour conclusions that would be impossible to discover using solely patient studies.
Keywords: Neuropsychology; Neuroscience; Brain; Behaviour; Lesions; Associations, Dissociations, Double Dissociations