Abstract:
Decision-making in the mammalian brain involves structures within the midbrain,
striatum, limbic system, and cortex. My colleagues and I studied the roles of several of
these structures in reward-processing and decision-making related phenomena. First, we found female rats were more likely to approach feeders outside the task context in an
operant chamber with two feeders. I speculate this sexual dimorphism relates to the
disproportionate effect of fasting on reproduction in female rats; this provides an
alternative to the widespread interpretation that male rats are more risk-seeking than
females. Next, we recorded field potentials (FPs) from seven brain regions as rats
completed a binary choice task to determine if reward information originated in a
particular area, and if the fidelity of information varied among them. Using a machine
learning classifier, we found reinforcement information was distributed across the
network and there was no canonical flow of information in the recorded structures.