Orbitofrontal and insular cortex: neural responses to cocaine-associated cues and cocaine self-administration.
Synapse
; 64(1): 1-13, 2010 Jan.
Article
em En
| MEDLINE
| ID: mdl-19725114
ABSTRACT
Based on neuro-imaging studies in cocaine-addicted humans, it is hypothesized that increases in neural activity within several regions of the prefrontal cortex contribute to cue-induced cocaine seeking and cocaine-induced compulsive drug self-administration. However, electrophysiological tests of these hypotheses are lacking. In the present study, animals were trained to self-administer cocaine (0.75 mg/kg) for 14 days. On the 14th day, we conducted electrophysiological recordings of lateral orbitofrontal (LO) and ventral anterior insula (AIV) neurons. A subset of the combined population of recorded neurons showed a change in firing rate in association with one or more of the following discrete events (1) presentation of a discriminative stimulus that signaled the onset of the self-administration session, (2) occurrence of the first cocaine-directed operant response, (3) occurrence of a cocaine-reinforced press, and (4) presentation of cues normally paired with delivery of the cocaine reinforcer. The majority of the stimulus- and response-related changes in firing involved a brief increase in firing during the stimulus and response event, respectively. In addition to these event-specific responses, approximately half of the recorded neurons exhibited a sustained change in average firing (i.e., discharges per 30-s bin) during the cocaine self-administration session, relative to average firing during a presession, drug-free period (referred to as session changes). The prevalence of session-increases and decreases were not significantly different. These and other findings are discussed in relation to hypotheses about cue-evoked and cocaine-maintained cocaine-directed behavior.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Córtex Pré-Frontal
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Cocaína
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Inibidores da Captação de Dopamina
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Transtornos Relacionados ao Uso de Cocaína
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Sinais (Psicologia)
Tipo de estudo:
Risk_factors_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article