Briefly Expanding on the Neuroantomy of Memory

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Briefly Expanding on the Neuroantomy of Memory
www.nature.com/.../v11/n9/full/4001881a.html
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Key Components
Bear et al., 2007
Synonyms Declarative Memory Explicit
Memory Nondeclarative Memory Implicit Memory
Procedure Memory
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Localization of Declarative Memory in the
Neocortex
If learning involves only one sensory modality
(vision) then memory will be stored in brain
regions involved in those regions. Inferotemporal
Cortex is an association area that processes
detailed visual information (see fMRI to the
right) With each exposure to a stimulus, cells
become more responsive to that stimulus resulting
in detailed discrimination (Hebbian Plasticity
more to come)
Bear et al., 2007
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Information from the inferotemporal cortex
(cortical association area) is sent to the
hippocampus and then back to the same area.
Bear et al., 2007
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Hippocampus Memory Relational Memory

• What is Relational Memory?
• Highly processed sensory information comes into
  the hippocampus and association corticesmemories
  are formed linking all the things happening at
  that time.
• With each review of the information, more
  specific and detailed information is linked to
  the original set of information. Everything is
  eventually stored in cortical association areas.
• The hippocampus links all this information and
  forms memories about the relations between
  stimuli. Even though the nature of the
  information is explicit, the way the information
  becomes linked makes some of it implicit. So
  Memory A which might be an explicit piece of
  information becomes implicitly linked to B
  which might have originally been explicit
  information. Example Searching for information
  on a page of something that you read and that you
  remember by the way the page looked (e.g., right
  side, below the picture, midway in the
  paragraph). This is declarative information that
  was implicitly linked.

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Procedural Memory

• Striatum (Caudate Putamen) is involved in
  Procedural Memory
• Sits in key location in the motor loop,
  receiving input from the frontal and parietal
  cortices and sending output to thalamic nuclei
  and cortical areas involved in movement.
• Primates with lesions of the striatum have no
  trouble with the formation of declarative memory
  but cannot respond in a specific way to a
  particular cue. They can move their limb but
  they cant make the stimulus-response connection.
• Huntington's disease kills neurons in the
  striatum. Patients have trouble linking a
  stimulus cue to a specific behavioral response
  (stimulus-response habit). Even though they have
  motor problems, the deficit in learning is worse
  than their motor problem.

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Working Memory Prefrontal Cortex

• Note how all prefrontal areas are associated
  with some aspect of working memory.

(refer to hippocampal formation and prefrontal
lobes diagrams in Expanding Neuroanatomy
lecture)
Bear et al., 2007