Timing-based LTP and LTD at vertical inputs to layer II/III pyramidal cells in rat barrel cortex.
Experience-dependent plasticity in somatosensory (S1) and visual (V1) cortex involves rapid depression of responses to a deprived sensory input (a closed eye or a trimmed whisker). Such depression occurs first in layer II/III and may reflect plasticity at vertical inputs from layer IV to layer II/III pyramids. Here, I describe a timing-based, associative form of long-term potentiation and depression (LTP/LTD) at this synapse in S1. LTP occurred when excitatory postsynaptic potentials (EPSPs) led single postsynaptic action potentials (APs) within a narrow temporal window, and LTD occurred when APs led EPSPs within a significantly broader window. This long LTD window is unusual among timing-based learning rules and causes EPSPs that are uncorrelated with postsynaptic APs to become depressed. This behavior suggests a simple model for depression of deprived sensory responses in S1 and V1.
Feldman
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DE
Neural Development Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Maryland 20892, USA. dfeldman@codon.nih.gov
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D000818:Animals; D004558:Electric Stimulation; D004594:Electrophysiology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D019706:Excitatory Postsynaptic Potentials / Q000187:drug effects / Q000502:physiology; D017774:Long-Term Potentiation / Q000187:drug effects / Q000502:physiology*; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D018408:Patch-Clamp Techniques; D017966:Pyramidal Cells / Q000187:drug effects / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000502:physiology; D013003:Somatosensory Cortex / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D013569:Synapses / Q000502:physiology; D014738:Vibrissae / Q000502:physiology; D015349:Vision, Monocular / Q000502:physiology
D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D015763:2-Amino-5-phosphonovalerate