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How do humans make choices between different types of rewards? Economists have long argued on theoretical grounds that humans typically make these choices as if the values of the options they consider have been mapped to a single common scale for comparison. Neuroimaging studies in humans have recently begun to suggest the existence of a small group of(More)
The ability of human subjects to choose between disparate kinds of rewards suggests that the neural circuits for valuing different reward types must converge. Economic theory suggests that these convergence points represent the subjective values (SVs) of different reward types on a common scale for comparison. To examine these hypotheses and to map the(More)
RATIONALE AND OBJECTIVE Relapse to drug use in humans can be induced by exposure to drug-associated cues. The ability of drug cues to provoke 'relapse' has been studied in laboratory animals using a reinstatement model in which resumption of drug seeking is assessed after extinction of drug-reinforced responding. In this model, there are no adverse(More)
AIMS To evaluate the effect of repeated high-frequency transcranial magnetic stimulation (rTMS) of the left dorsolateral prefrontal cortex (DLPFC), combined with either smoking or neutral cues, on cigarette consumption, dependence and craving. DESIGN Participants were divided randomly to real and sham stimulation groups. Each group was subdivided randomly(More)
Drug addiction is associated with long-lasting neuronal adaptations including alterations in dopamine and glutamate receptors in the brain reward system. Treatment strategies for cocaine addiction and especially the prevention of craving and relapse are limited, and their effectiveness is still questionable. We hypothesized that repeated stimulation of the(More)
The rewarding effects of drugs of abuse are thought to be dependent on the mesocorticolimbic dopamine system, which originates in the ventral tegmental area (VTA) and projects into the nucleus accumbens (NAC) and other forebrain regions. Heroin, by inhibiting GABAergic interneurons in the VTA, induces local dopaminergic activation and release in the NAC(More)
The Flinders Sensitive Line of rats is a widely accepted and validated model of depression. These rats demonstrate abnormalities in limbic dopamine neurotransmission, suggesting disturbed neuronal activity in the ventral tegmental area. Interspike interval time series were recorded from the ventral tegmental area of the control Sprague-Dawley and Flinders(More)
Reconsolidation of long-term memory is blocked in animal models by macromolecular synthesis inhibitors, resulting in item-specific post-retrieval amnesia. The induction of such amnesia could ameliorate traumatic memories and phobias. However, this pharmacological approach is of limited value in humans because of toxicity. Here we report that reconsolidation(More)
The internal state of an organism affects its choices. Previous studies in various non-human animals have demonstrated a complex, and in some cases non-monotonic, interaction between internal state and risk preferences. Our aim was to examine the systematic effects of deprivation on human decision-making across various reward types. Using both a(More)
According to the United Nations, approximately 24.7 million people used am-phetamines, 16 million used cocaine, and 12 million used heroin in 2006/07 [Costa, 2008]. Full recovery from drug addiction by chemical treatment and/or social and psychological support is uncertain. The present investigation was undertaken to expand our understanding of the factors(More)