[0] Buonomano DV, Merzenich MM, Cortical plasticity: from synapses to maps.Annu Rev Neurosci 21no Issue 149-86 (1998)


{627} revision 1 modified: 10-07-2008 03:27 gmt

PMID-9530495[0] Cortical plasticity: from synapses to maps

  • focuses on synaptic plasticity as the underlying mechanism of behavior-dependent cortical maps/representations.
  • "within limits, the cortex can allocate cortical area in a use-dependent manner"
  • synaptic plasticity -> STDP via NMDA, etc.
    • demonstrated with intracellular recordings of cat M1 & simultaneous stimulation of the ventrolateral thalamus & intracellular depolarization. Facilitation was short lasting and not present in all neurons.
    • demonstrated in rat auditory cortex / recording in layer 2/3 , stimulate layer 2/3 & White matter/6.
    • review of Ca+ hypothesis of LTP/LTD balance: if the Ca+ influc is below a threshold, LTD occurs; if it is above a certain threshold, LTP.
      • not sure how long LTD has been demonstrated -- 15 min?
  • cellular conditioning = direct induction of plastic changes in the selective responses of individual neurons in vivo as a result of short-term conditioning protocols. this is what we are interested in, for now.
    • this review does not explicitly deal with BG-DA / ACh reinforcement, only timing dependent plasticity, in visual and auditory cortex.
  • cortical plasticity:
    • talk about the revealing/unmasking of hidden responses when sections of cortex are deafferented or digits were amputated.
    • talk about training-based approaches: training increases cortical representation of a sensory modality / skill/ etc. The cortex can differentially 'allocate' area in a use-dependent manner throughout life.
    • cortical map changes are not reflected by changes in thalamic somatotopy.

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