Rudd Custers
Wednesday 23rd July 2014
Time: 4pm
Basement Seminar Room
Alexandra House, 17 Queen Square, London, WC1N 3AR
Rudimentary Effort Responses to Reward Cues and Striatal Dopaminergic Functioning
Reward cues have been found to increase the investment of effort in tasks even when those cues are presented subliminally (i.e., below the threshold of conscious awareness). These effort responses are assumed to rely on the mesolimbic dopamine system, which includes the ventral striatum. This talk will review our earlier work on the effects of subliminally presented reward cues, and three recent studies will be presented that explore the role of striatal dopaminergic functioning. The first two studies investigated whether effort responses vary with individual differences in markers of striatal dopaminergic functioning. In both studies, effort responses to subliminal reward cues were found to be correlated with the respective markers, which was not the case for responses to supraliminal reward cues. These findings support the idea that effort responses to subliminal reward cues are produced by a rudimentary reward mechanism, while responses to supraliminal reward cues depend also on higher-level cognitive functions. In a final fMRI study, we obtained behavioural effects of subliminal reward cues in the absence of evidence for activation of the ventral striatum or other reward related areas. Potential explanations for this will be discussed.