There are many who have questioned the logic of double dissociations as a means of identifying particular brain areas as the substrates for particular functions. One criticism is that this approach assumes that a specific region of the brain has a unitary function when there is considerable evidence for one anatomically or histologically identifiable area to have a multiplicity of different functions. Another is that there are only double dissociations when in fact there may be triple or even quadruple dissociations – situations that are almost impossible to test in a tractable way. Certainly, double dissociations are not appropriate for uncovering brain-behavior relationships from a developmental perspective as striking dissociations are rare in children and if present interpretation is hampered due to changes in impairments with age. According to
Dorothy V.M. Bishop, group studies are needed aimed at showing how associations, rather than dissociations by means of single-case studies, between impairments develop.
See Agnosia, Brain-damage studies, Cerebral cortex (functions), Configural processing, Cortical lobes, Domain specificity, Exeprimental method, Impairment, Innate modularity hypothesis, Modularity, Neuropsychology, Recall memory, Recognition memory