Substantial evidence indicates that subjective value is adapted to the statistics of reward expected within a given temporal context. However, how these contextual expectations are learned is poorly understood. To examine such learning, we exploited a recent observation that participants performing a gambling task adjust their preferences as a function of context. We show that, in the absence o...

WOLF, GEORGE. Hypothalamic regulation of sodium intake: relations to preoptic and tegmental function. Am. J. Physiol. 213(G): 1433-1438. 1967.-Rats with lesions of the septum, lateral preoptic area, or ventral tegmental area of Tsai showed no impairment of sodium appetite after adrenalectomy, acute sodium depletion, or deoxycorticosterone treatment. Rats with lesions of the lateral hypothalamus...

Dopamine neurons signal reward prediction errors. This requires accurate reward predictions. It has been suggested that the ventral striatum provides these predictions. Here we tested this hypothesis by recording from putative dopamine neurons in the VTA of rats performing a task in which prediction errors were induced by shifting reward timing or number. In controls, the neurons exhibited erro...

An assortment of human behaviors is thought to be driven by rewards including reinforcement learning, novelty processing, learning, decision making, economic choice, incentive motivation, and addiction. In each case the ventral tegmental area/ventral striatum (nucleus accumbens) (VTA-VS) system has been implicated as a key structure by functional imaging studies, mostly on the basis of standard...

Studies suggest that dopaminergic neurons report a unitary, global reward prediction error signal. However, learning in complex real-life tasks, in particular tasks that show hierarchical structure, requires multiple prediction errors that may coincide in time. We used functional neuroimaging to measure prediction error signals in humans performing such a hierarchical task involving simultaneou...

Orbitofrontal cortex (OFC) has been implicated in signalling reward expectancies, but its exact role , and how this differs from that the role of ventral striatum (VS), is an open question. One idea is that VS is the seat of value learning in model-free, dopamine-dependent reinforcement learning, while OFC represents values in dopamine-independent model-based learning. However, recent results [...