Dissociation

Cards (6)

  • Dissociating cognitive functions, and brain regions
    • Cognitive functions can be dissociated (separated to a degree) from each other through selective impairment
    • & for function of brain regions
  • Dissociation studies
    • require minimum of 2 groups & 2 tasks.
    • Comparison between patient/control groups shows deficit
    • 2 tasks needed to determine whether deficit specific to particular function, or reflects more general impairment
  • Single dissociation
    • Performance in declarative task lower in temporal lobe deficits than nondeclaritive
    • control performance = both same = temporal lobes involved in declarative memory
  • Limits of single dissociation 

    • result suggest temporal lobes involved in declarative memory
    • conclusion = temporal lobes involved in declarative memory, & NOT in nondeclarative memory, does NOT follow
    = possible that poor performance caused by another factor -
    e.g. deficit in concentration, - test of declarative memory required more concentration than test of nondeclarative me
  • Double dissociation example 

    • temporal lobe deficits = lower performance in declarative memory = temporal lobes involved in declarative memory
    • cerebellum deficits = lower performance in nondeclarative memory = cerebellum involved in nondeclarative memory
  • Double dissociation provides evidence that
    • some cognitive processes = critical for task X = not critical for task Y & vice versa
    • brain-area A critical for task X but not Y
    • performance differences reflect functional differences between groups, rather than unequal sensitivity of 2 tasks = confidence in task
    • Participants don‘t have to be perfectly intact on either task - just need to be significantly better at one task than other