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Motivational functions of the human midbrain| title | Motivational functions of the human midbrain |
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| start_date | 2022/06/23 |
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| schedule | 14h |
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| online | no |
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| summary | Although a substantial body of work has associated dopamine neurons with the processing of errors in the prediction of both the subjective value
and motivational salience of outcomes, the exact nature of these signals remained disputed. The single dimension hypothesis (Matsumoto & Hikosaka, 2009) proposed that the dopaminergic midbrain encodes subjective value across the full spectrum of reward and punishment whereas the dual dimension hypothesis (Fiorillo, 2013) proposes that value coding is limited to coding evidence about reward. In this talk, I will approach this issue with neuroimaging of the human midbrain. In a Pavlovian task, different cues predicted aversive, appetitive, or neutral liquids with different probabilities (p=0.0, 0.5, or 1.0). The motivational salience of appetitive and aversive liquids was carefully matched for each participant. Both ratings and midbrain activity at cue and outcomes reflected subjective value prediction errors. Analyses limited to the aversive and appetitive domain revealed that the coding of value was largely limited to evidence about reward, in line with the dual dimension hypothesis. Moreover, cue-induced midbrain activity increased with physical salience as measured by pupil diameter, and outcome-induced responses correlated with motivational salience, in line with multiple midbrain functions. These findings suggest cross-species convergence of midbrain responding to outcomes with motivational meaning and open avenues for physiologically informed neuroimaging approaches. |
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| responsibles | Epinat-Duclos |
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Workflow history| from state (1) | to state | comment | date |
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| submitted | published | | 2022/06/16 09:47 UTC |
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