Paradoxical False Memory for Objects After Brain Damage

Novel or Familiar? Amnesia is characterized by a number of memory deficits, including the apparent inability to distinguish between novel and familiar stimuli. McTighe et al. (p. 1408 ; see the Perspective by Eichenbaum ) observed that the recognition memory of brain-damaged rats in a standard model of amnesia was impaired not because previously experienced objects seemed to be novel, but because objects not previously experienced seemed to be familiar. Furthermore, simply placing the animal in a visually deprived environment during the delay, reducing visual interference, completely rescued the impairment. This counterintuitive finding contradicts the predominant “multiple memory systems” model in which amnesia is usually considered and forces a reconsideration of fundamental assumptions underlying our understanding of amnesia.