Long-term enhancement of synaptic responses in the songbird hippocampus

doi:10.1016/0006-8993(91)90382-6

Brain Research

Volume 538, Issue 1, 4 January 1991, Pages 102-106

https://doi.org/10.1016/0006-8993(91)90382-6 Get rights and content

Abstract

Electrophysiological recordings from the hippocampus were taken using brain slices from 1-year-old, female, song sparrows (Melospiza melodia). The evoked responses were smaller and less stable as compared with those obtained from the mammalian hippocampus. They consisted of two spikes. The first spike had low calcium dependency and represented mainly fiber potential. The second spike demonstrated a clear calcium dependency proving its synaptic origin. Paired-pulse facilitation showed inhibition of the second response at latencies below 20 ms, facilitation at 30 ms and no changes above 30 ms. Train stimulation with 20 Hz (each train consisted of 1 s stimulation with 10-s intervals repeated 3 times) evoked a stable increase in the size of the evoked response lasting approximately 2 h. These data indicate that the avian hippocampus possesses several neurophysiological properties that typify the mammalian hippocampus including the long-term enhancement of the synaptic response following certain patterns of stimulation.

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Long-term enhancement of synaptic responses in the songbird hippocampus

Abstract

Physiol. Behav.

Brain Research

Brain Research

Brain Research

Neuropsychologia

Neurosci. Lett.

Beh. Brain Res.

Exp. Neurol.

Brain Res. Rev.

J. Neurosci. Methods

Neuroscience

Brain Research

Unit analysis of hippocampal population spikes

Exp. Brain Res.

Control of hippocampal output by afferent volley frequency

Long-term changes in synaptic efficacy: potential mechanisms and implications

The avian hippocampus: its role in the neural organization of the spatial behavior of homing pigeons

Behavioral and anatomical studies of the avian hippocampus

Long-lasting potentiation of synaptic transmission in the dentate area of the anaesthetized rabbit following stimulation of the perforant path

J. Physiol. (Lond.)