Refining the temporal definition of an association at the neuronal level using long-term potentiation and long-term depression in the dentate gyrus.
This study sharpens the temporal definition of an association in the context of long-term synaptic modification of the monosynaptic projections from entorhinal cortex to dentate gyrus in the anesthetized rat. The ipsilateral projection produces a powerful postsynaptic excitation and shows synaptic potentiation following 7.5 ms trains. On the other hand, brief, high-frequency contralateral stimulation just after this powerful postsynaptic excitation is followed by long-term depression (LTD) at the synapses of this pathway. Therefore, based on the differential induction of long-term potentiation (LTP) or LTD, a cell can distinguish associated pre- and postsynaptic activation at a temporal resolution at least as small as 7.5 ms.
Hashemzadeh-Gargari
H
H
Department of Neurological Surgery, University of Virginia Health Sciences Center, Charlottesville 22908.
Colbert
C M
CM
Levy
W B
WB
D000818:Animals; D003213:Conditioning, Psychological; D004558:Electric Stimulation; D005071:Evoked Potentials; D007839:Functional Laterality; D006624:Hippocampus / Q000502:physiology*; D008297:Male; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*; D051381:Rats; D011919:Rats, Inbred Strains; D013569:Synapses / Q000502:physiology*; D013997:Time Factors