Neuromodulation and the functional dynamics of piriform cortex.
Acetylcholine and norepinephrine have a number of effects at the cellular level in the piriform cortex. Acetylcholine causes a depolarization of the membrane potential of pyramidal cells and interneurons, and suppresses the action potential frequency accommodation of pyramidal cells. Acetylcholine also has strong effects on synaptic transmission, suppressing both excitatory and inhibitory synaptic transmission. At the same time as it suppresses synaptic transmission, acetylcholine enhances synaptic modification, as demonstrated by experiments showing enhancement of long-term potentiation. Norepinephrine has similar effects. In this review, we discuss some of these different cellular effects and provide functional proposals for these individual effects in the context of the putative associative memory function of this structure.
Linster
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Department of Neurobiology and Behavior, Cornell University, 245 Seeley G. Mudd Hall, Ithaca, NY 14853, USA. cl224@cornell.edu
Hasselmo
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ME
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D018678:Cholinergic Agents / Q000494:pharmacology; D004193:Discrimination Learning / Q000502:physiology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D018377:Neurotransmitter Agents / Q000494:pharmacology / Q000502:physiology; D009638:Norepinephrine / Q000494:pharmacology / Q000502:physiology*; D009833:Olfactory Pathways / Q000502:physiology*; D051381:Rats; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*
D018678:Cholinergic Agents; D018377:Neurotransmitter Agents; D009638:Norepinephrine