Michael Treadway
Department of Psychology
Emory University
Effort-Expenditure and Its Discontents
Despite the broad literature examining the causes and consequences of mood, the concept of mood remains to be ambiguous. Prior work suggests that reward, effort, and exploration each contribute to mood, yet most laboratory assessments have assessed the impact of these variables in isolation. In this talk, I will present data from six samples using a novel effortful exploration task. We find that effort expenditure, exploration, reward and their trial-wise prediction-errors are independent predictors of momentary mood. Importantly, effort appeared to have dual, opposing effects on mood: on one hand, increased effort expenditure predicted more negative mood, and on the other hand, reward predicted subsequent mood only when foraging required effort. Finally, I will present preliminary evidence supporting a causal role for dmPFC in the impact of effort on mood using temporal interference (TI), a novel non-invasive deep-brain stimulation method. Taken together, these data seek to advance our understanding of mood and shed light on the paradoxical nature of effort as having both value-enhancing and discounting effects.