Firing patterns of nucleus accumbens neurons during cocaine self-administration in rats

doi:10.1016/0006-8993(93)90557-4

Brain Research

Volume 626, Issues 1–2, 29 October 1993, Pages 14-22

https://doi.org/10.1016/0006-8993(93)90557-4 Get rights and content

Abstract

The firing patterns of neurons in the nucleus accumbens (NA) were recorded in rats trained to self-administer cocaine via response contingent intravenous drug infusions. Recordings were obtained from permanently implanted multiple electrode arrays (8 microwires) inserted bilaterally into the NA and/or ventral striatum (NA-VS) in animals exhibiting stable responding (inter-infusion intervals, INT) during test sessions consisting of 16–30 drug delivery episodes. Electronically isolated and identified NA-VS neurons showed distinct patterns of phasic increases in firing relative to the occurrence of the reinforced lever press. Two particular firing patterns, however, were repeatedly encountered in different animals. In one type, a marked increase was observed in discharge following response contingent drug delivery. A second firing pattern showed two distinct temporally separated brief firing peaks (bursts), one immediately prior to the initiation of responding, and the other a brief discharge commencing within 200 ms after the initiation of drug delivery. The time between firing peaks was found to be modifiable by changing the response/reward (FR) ratio for drug delivery. A third finding was that the correlates of the self-administration response were not solely the result of drug infusion since, (1) phasic firing increases were not observed when the drug was delivered non-contingently during the same session and, (2) the emergence of patterns was frequently delayed within the session until after drug self-administration behavior stabilized at regular INTs. The findings are discussed in terms of the significance of NA-VS neuron firing correlates for the initiation and maintenance of cocaine self-administration.

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Multiple lines of experimental evidence implicate the nucleus accumbens (NAc, part of the ventral striatum) in reward-based learning and decision-making (Apicella et al., 1991; Cador et al., 1989; Carelli et al., 1993; Cox and Witten, 2019; Di Ciano et al., 2001; Everitt et al., 1991; Parkinson et al., 1999; Phillips et al., 1993, 1994; Robbins et al., 1989; Roitman et al., 2005; Setlow et al., 2003; Stuber et al., 2011; Taylor and Robbins, 1986).
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Firing patterns of nucleus accumbens neurons during cocaine self-administration in rats

Abstract

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Trends Pharmacol. Sci.

Alcohol

Pharmacol. Biochem. Behav.

Brain Res.

Neuropharmacology

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Pharmacol. Biochem. Behav.

Trends Pharmacol. Sci.

Neuroscience

Pharmacol. Biochem. Behav.

Responses to reward in monkey dorsal and ventral striatum

Exp. Brain Res.

Correlation between nucleus accumbens neuronal activity and cocaine self-administration behavior in rats

Soc. Neurosci. Abstr.

Review: D1 dopamine receptor-the search for a function: A critical evaluation of the D1/D2 dopamine receptor classification and its functional implications

Synapse

Heroin and cocaine intravenous self-administration in rats: mediation by separate neural system

Psychopharmacology