Is the short-latency dopamine response too short to signal reward error?
Unexpected stimuli that are behaviourally significant have the capacity to elicit a short-latency, short-duration burst of firing in mesencephalic dopaminergic neurones. An influential interpretation of the experimental data that characterize this response proposes that dopaminergic neurones have a crucial role in reinforcement learning because they signal error in the prediction of future reward. In this article we propose a different functional role for this 'short-latency dopamine response' in the mechanisms that underlie associative learning. We suggest that the initial burst of dopaminergic-neurone firing could represent an essential component in the process of switching attentional and behavioural selections to unexpected, behaviourally important stimuli. This switching response could be a crucial prerequisite for associative learning and might be part of a general short-latency response that is mediated by catecholamines and prepares the organism for an appropriate reaction to biologically significant events. Any act which in a given situation produces satisfaction becomes associated with that situation so that when the situation recurs the act is more likely than before to recur also. E.L. Thorndike (1911) 1.
Redgrave
P
P
Dept of Psychology, University of Sheffield, Sheffield, UK S10 2TP.
Prescott
T J
TJ
Gurney
K
K
D000200:Action Potentials; D000818:Animals; D001244:Association; D001288:Attention / Q000502:physiology; D001362:Avoidance Learning / Q000502:physiology; D001479:Basal Ganglia / Q000502:physiology; D001522:Behavior, Animal / Q000502:physiology; D002395:Catecholamines / Q000502:physiology; D003216:Conditioning, Operant / Q000502:physiology; D004298:Dopamine / Q000502:physiology*; D005106:Exploratory Behavior; D006801:Humans; D007858:Learning / Q000502:physiology; D008636:Mesencephalon / Q000502:physiology*; D008959:Models, Neurological; D008960:Models, Psychological; D011930:Reaction Time / Q000502:physiology; D012054:Reinforcement, Psychology; D012201:Reward; D013997:Time Factors
D002395:Catecholamines; D004298:Dopamine