Why does double dissociation in neuropsychological studies, such as in Broca's and Wernicke's aphasia, provide stronger evidence for functional specialization than single dissociation?

💡 Explanation

Double dissociation shows that damage to area A impairs function X but not Y, while damage to area B impairs function Y but not X. Therefore, this pattern strengthens the conclusion that X and Y rely on separate neural substrates, rather than one area simply being more sensitive to impairment generally.

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