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Why does brain damage impair memory? A connectionist model of object recognition memory in perirhinal cortex

By Rosemary A. Cowell, Timothy J. Bussey and Lisa M. Saksida

Abstract

Object recognition is the canonical test of declarative memory, the type of memory putatively impaired after damage to the temporal lobes. Studies of object recognition memory have helped elucidate the anatomical structures involved in declarative memory, indicating a critical role for perirhinal cortex. We offer a mechanistic account of the effects of perirhinal cortex damage on object recognition memory, based on the assumption that perirhinal cortex stores representations of the conjunctions of visual features possessed by complex objects. Such representations are proposed to play an important role in memory when it is difficult to solve a task using representations of only individual visual features of stimuli, thought to be stored in regions of the ventral visual stream caudal to perirhinal cortex. The account is instantiated in a connectionist model, in which development of object representations with visual experience provides a mechanism for judgment of previous occurrence. We present simulations addressing the following empirical findings: (1) that impairments after damage to perirhinal cortex (modeled by removing the perirhinal cortex layer of the network) are exacerbated by lengthening the delay between presentation of to-be-remembered itemsandtest, (2) that such impairments are also exacerbated by lengthening the list of to-be-remembered items, and (3) that impairments are revealed only when stimuli are trial unique rather than repeatedly presented. This study shows that it may be possible to account for object recognition impairments after damage to perirhinal cortex within a hierarchical, representational framework, in which complex conjunctive representations in perirhinal cortex play a critical role

Topics: QA76
Publisher: Society of Neuroscience
Year: 2006
OAI identifier: oai:kar.kent.ac.uk:24044

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Citations

  1. (2003). A
  2. (1999). Dissociation between the effects of damage to perirhinal cortex and area TE. Learn Mem 6:572–599.
  3. (1997). Extensive cytotoxic lesions involving both the rhinal cortices and area TE impair recognition but spare spatial alternation in the rat. doi
  4. (1997). Functional double dissociation between two inferior temporal cortical areas: perirhinal cortex versus middle temporal gyrus.
  5. (2005). Functional specialization in the human medial temporal lobe.
  6. (2004). Impaired recency judgments and intact novelty judgments after fornix transection in monkeys. doi
  7. (1997). Impairment of visual object-discrimination learning after perirhinal cortex ablation. doi
  8. (2003). Impairments in visual discrimination after perirhinal cortex lesions: testing “declarative” vs. “perceptual-mnemonic” views of perirhinal cortex function. doi
  9. (1992). Monkeys(Macacafascicularis)withrhinalcortex ablations succeed in object discrimination learning despite 24-hr intertrial intervals and fail at matching to sample despite double sample presentations. doi
  10. (2001). Neurotoxic lesions of perirhinal cortex impair visual recognition memory in rhesus monkeys. doi
  11. (1996). Neurotoxic lesions of the perirhinal cortex do not mimic the behavioural effects of fornix transection in the rat. doi
  12. (1996). Neurotoxiclesionsoftheperirhinal cortex do not mimic the behavioural effects of fornix transection in the rat.
  13. (2005). Object memory and perception in the medial temporal lobe: an alternative approach. doi
  14. (2005). Objectmemoryandperceptioninthemedial temporal lobe: an alternative approach.
  15. (1924). Oblivescence during sleep and waking. doi
  16. (2001). Opposite relationship of hippocampal and rhinal cortex damage to delayed nonmatching-to-sample deficits inmonkeys. Hippocampus 11:61–71. doi
  17. (2001). Opposite relationship of hippocampal and rhinalcortexdamagetodelayednonmatching-to-sampledeficitsinmonkeys. Hippocampus 11:61–71.
  18. (2000). Perception and recognition memory in monkeys following lesions of area TE and perirhinal cortex. doi
  19. (2005). Perceptual deficits in amnesia: challenging the medial temporal lobe “mnemonic” view.
  20. (1998). Perirhinal cortex ablation impairs configural learning and paired-associate learning equally. doi
  21. (1994). Preserved recognition memory for small sets, and impaired stimulus identification for large sets, following rhinal cortex ablations in monkeys. doi
  22. (1974). Recognition impaired and association intact in the memory of monkeys after transection of the fornix. doi
  23. (2001). Recognition memory: what are the roles of the perirhinal cortex and hippocampus? Nat Rev Neurosci 2:51–61. doi
  24. (2001). Recognitionmemory:whataretherolesof the perirhinal cortex and hippocampus?
  25. (2004). Recollection-like memory retrieval in rats is dependent on the hippocampus. doi
  26. Saksida LM,Murray EA (2002) Perirhinal cortex resolves feature ambiguity in complex visual discriminations. doi
  27. (1984). Self-organization and associative memory. doi
  28. (1998). The human perirhinal cortex and recognition memory. Hippocampus 8:330–339. doi
  29. (2002). The organization of visual object representations: a connectionist model of effects of lesions in perirhinal cortex. doi
  30. (1994). Two functional components of the hippocampal memory system. doi

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