What does a double dissociation demonstrate about cognitive modules?

What does a double dissociation demonstrate about cognitive modules?

• A. That separate brain modules can support different cognitive functions
• B. That a single brain region controls all cognitive functions
• C. That cognitive functions are not localized in the brain
• D. That impairments cannot reveal brain structure relationships

Answer: (A)

Double dissociation shows that different cognitive abilities rely on distinct neural substrates, meaning separate brain modules can support different functions. In the classic pattern, one person has trouble with function A but not function B, while another person has trouble with function B but not function A. This independence indicates that A and B depend on different brain areas, supporting the idea of modular, localized cognitive processes. It’s stronger evidence for distinct neural systems than a single dissociation, and it rules out the notion that a single region underlies all functions.

Double dissociation shows that different cognitive abilities rely on distinct neural substrates, meaning separate brain modules can support different functions. In the classic pattern, one person has trouble with function A but not function B, while another person has trouble with function B but not function A. This independence indicates that A and B depend on different brain areas, supporting the idea of modular, localized cognitive processes. It’s stronger evidence for distinct neural systems than a single dissociation, and it rules out the notion that a single region underlies all functions.