What does double dissociation indicate about cognitive architecture?

What does double dissociation indicate about cognitive architecture?

• A. Separate modules underlie different presentations
• B. A single generalized module explains all tasks
• C. Cognitive functions are not localized at all
• D. There is no modular organization in the brain

Answer: (A)

Double dissociation shows that cognitive operations rely on separate, specialized subsystems that can be disrupted independently. When one person’s brain damage impairs Task A but not Task B, and another person’s damage impairs Task B but not Task A, it reveals that Task A and Task B depend on different neural circuits. This functional independence argues for a modular organization of cognitive architecture: distinct modules support different tasks, rather than a single generalized system handling everything. This pattern also challenges views that cognitive functions are not localized or that there is no modular structure. If a single module underlay all tasks, or if brain damage produced the same deficits across tasks, we wouldn’t see opposite, task-specific impairments across cases.

Double dissociation shows that cognitive operations rely on separate, specialized subsystems that can be disrupted independently. When one person’s brain damage impairs Task A but not Task B, and another person’s damage impairs Task B but not Task A, it reveals that Task A and Task B depend on different neural circuits. This functional independence argues for a modular organization of cognitive architecture: distinct modules support different tasks, rather than a single generalized system handling everything.

This pattern also challenges views that cognitive functions are not localized or that there is no modular structure. If a single module underlay all tasks, or if brain damage produced the same deficits across tasks, we wouldn’t see opposite, task-specific impairments across cases.