Modulation of the Hippocampal θ-Rhythm as a Mechanism for Anesthetic-Induced Amnesia

Chapter
Part of the Contemporary Clinical Neuroscience book series (CCNE)

Abstract

Understanding the mechanisms of anesthetic interference with memory and consciousness is of scientific value and clinical importance. For the clinician, the ability to precisely monitor the effect of anesthetics on the brain, the organ where anesthetic drugs exert their core effects (effects on all other organs, no matter how profound, are side effects), would be practice changing.

The last decades have witnessed a momentous increase in the interest of the (neuro) scientific community in synchronized neuronal activity, the “rhythms of the brain” (Buzsaki. 2006. Rhythms of the Brain. 1 ed. New York: Oxford University Press). As their links to higher cognitive function become unraveled, mechanistically grounded approaches to understanding, measuring, and predicting drug effects on the mind become fathomable. This chapter will review the evidence suggesting that the ability of the brain to form explicit memories is dependent on the precise timing of synchronized neuronal activity in the hippocampus that presents as the θ-rhythm. Based on experiments in our lab, we will then develop the argument that anesthetic-induced amnesia is, at some point, reflected by the θ-rhythm and hence can be measured and quantified.

Keywords

Anesthesia hippocampus θ-rhythm gamma oscillations 40 Hz rhythms amnesia learning memory 

Notes

Acknowledgements

Supported by National Institutes of Health (Bethesda, MD, USA) GM47818 (to M. Perouansky and R. Pearce) and NS056411 (to R. Pearce) and the Department of Anesthesiology, University of Wisconsin, Madison, WI, USA

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© Humana Press, a part of Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of AnesthesiologyUniversity of Wisconsin, SMPH B6/319 Clinical Science CenterMadisonUSA
  2. 2.Department of AnesthesiologyUniversity of WisconsinMadisonUSA

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