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bioRxiv · 10.1101/2021.06.29.450435

Prenatal alcohol exposure disrupts hippocampal sharp-wave ripple-associated spike dynamics

Harvey, R. E.·Berkowitz, L. E.·Savage, D. D.·Clark, B. J.
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Abstract

Prenatal alcohol exposure (PAE) is among the most common developmental insults to the nervous system and is characterized by memory disruption. There is a pressing need to identify physiological alterations that help explain this memory impairment. Hippocampal sharp-wave ripples (SPW-Rs) are a compelling candidate for this purpose as they are the electrophysiological signatures of memory consolidation. We report that rats exposed to moderate prenatal alcohol display abnormalities restricted to SPW-R episodes that manifest as decreased recruitment of CA1 pyramidal cells and interneurons to SPW-R events, altered excitation during SPW-Rs, and decreased cell assembly activation rate. These differences observed at the single neuron and the population level may limit the ability of memory trace reactivation during SPW-Rs through the disruption of the intrinsic structure of cell sequences. Together, our results suggest that alterations in hippocampal SPW-R spike dynamics may underlie alcohol exposure-related memory deficits.

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Harvey, R. E., Berkowitz, L. E., Savage, D. D., Clark, B. J.. 2021-07-01. Prenatal alcohol exposure disrupts hippocampal sharp-wave ripple-associated spike dynamics. https://doi.org/10.1101/2021.06.29.450435

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