Nathaniel Daw
Princeton Neuroscience Institute and Psychology Department
Princeton University
I will present a very informal overview of a line of work I’ve been involved with for some years. This concerns a particular variable — the long-run average reward per timestep — which we believe the brain tracks and uses to guide behavior in a variety of circumstances. These include choices involving energetic expenditure, vigor and motivation; aspiration levels and whether to settle or seek alternative options in situations like foraging or mate selection; patience and time discounting; and self control and automaticity vs. deliberation. Computationally, this is because at least in some circumstances, the average reward measures the opportunity cost of time spent, which gives it a key role assessing tradeoffs and prioritization among different possible options. I’ll discuss some of our attempts to measure peoples’ use of this quantity experimentally, and to relate it to underlying biological systems including dopamine and stress hormones. The main goal of this presentation, however, is to brainstorm with the CCNP community as to whether this mechanism is relevant to disorders of mood, particularly depression, and about experimental strategies we might pursue to test this.
