Research

Electric barrier-induced voluntary abstinence reduces alcohol seeking in male, but not female, iP rats.

Maintaining abstinence and preventing relapse are key to the successful recovery from alcohol use disorder. There are two main ways individuals with alcohol use disorder abstain from alcohol use: forced (e.g., incarceration) and voluntary. Voluntary abstinence is often evoked due to the negative consequences associated with excessive alcohol consumption. This study investigated relapse-like behavior to alcohol seeking following acute, forced, and voluntary abstinence. Male rats had increased operant self-administration responding throughout training compared to females; however, females consumed greater amounts of alcohol in g/kg. Both male and female rats achieved voluntary abstinence, whic...
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Can the resting state peak alpha frequency explain the relationship between temporal resolution power and psychometric intelligence?

The temporal resolution power (TRP) hypothesis states that individuals with higher TRP, as reflected by a higher performance on several psychophysical timing tasks, perform better on intelligence tests due to their ability to process information faster and coordinate their mental operations more effectively. It is proposed that these differences in TRP are related to the rate of a master clock based on neural oscillations. The present study aimed to investigate whether the peak alpha frequency (PAF) measured via electroencephalography (EEG) reflects a psychophysiological measure of this rate and its potential role in explaining the relationship between TRP and psychometric intelligence. A sa...
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Kamin blocking is disrupted by low-dose ketamine in mice: Further implications for aberrant stimulus processing in schizophrenia.

Previous studies have shown that low doses of ketamine, an N-methyl-D-aspartate receptor antagonist, produce aberrantly strong internal representations of associatively activated but absent stimuli in humans and nonhuman animals, suggesting the validity of ketamine treatment as a preclinical model of the positive symptoms of schizophrenia, including hallucinations and delusions. However, whether acute ketamine treatment also impairs the ability to ignore present but informationally redundant stimuli, which is another hallmark of schizophrenia, remains unclear. Accordingly, the present study investigated whether injections of low-dose ketamine attenuate Kamin blocking in an appetitive conditi...
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Predictions about reward outcomes in rhesus monkeys.

Human infants and nonhuman animals respond to surprising events by looking longer at unexpected than expected situations. These looking responses provide core cognitive evidence that nonverbal minds make predictions about possible outcomes and detect when these predictions fail to match reality. We propose that this phenomenon has crucial parallels with the processes of reward prediction error, indexing the difference between expected and actual reward outcomes. Most work on reward prediction errors to date involves neurobiological techniques that cannot be implemented in many relevant populations, so we developed a novel behavioral task to assess monkeys’ predictions about reward outcomes...
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Morphine exposure during adolescence induces enduring social changes dependent on adolescent stage of exposure, sex, and social test.

Drug exposure during adolescence, when the “reward” circuitry of the brain is developing, can permanently impact reward-related behavior into adulthood. Epidemiological studies show that opioid treatment during adolescence, such as pain management for a dental procedure or surgery, increases the incidence of psychiatric illness including substance use disorders. Moreover, the opioid epidemic currently in the United States is affecting younger individuals raising the impetus to understand the pathogenesis of the negative effects of opioids. One reward-related behavior that develops during adolescence is social behavior. We previously demonstrated that developmental changes in the nucleus ...
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