Which term describes a pattern where impairment in one function is observed with preserved performance in another function?

• A. Dissociations
• B. Associations
• C. Double Dissociations
• D. Modularity

Answer: (A)

A dissociation describes a pattern where impairment in one function occurs while another function remains relatively preserved. This shows that the two abilities rely on different neural processes or systems, suggesting some independence between them. In practice, a single dissociation is when one cognitive function is impaired and another is intact, pointing to distinct underlying mechanisms. By contrast, an association would imply that the two functions tend to be affected together, not separately. A double dissociation goes a step further, demonstrating two opposite patterns across different cases (one function impaired with the other preserved, and vice versa), which strengthens the argument for separate neural substrates. Modularity is a broader idea about the mind having specialized modules, but it doesn’t by itself describe this specific pattern of selective impairment.