Representations and Causal Contributions of Frontal Cortical Regions During Context-Dependent Decision Making

Abstract

Although a growing body of research is starting to shed light into the neural mechanisms underlying our ability to accumulate evidence to form decisions, the process by which the brain flexibly utilizes these mechanisms to inform context-dependent decision making remains relatively unexplored. Groundbreaking work in this area was presented by Mante et al in 2013, who were able to successfully train macaque monkeys to complete a task requiring flexible selection and integration of visual evidence. Following the authors’ investigation of the role of frontal eye fields in this task, however, little follow up work has been conducted to further investigate the mechanisms and causal contributions of different brain areas to this process. One of the main limiting factors in achieving this goal is the long time required to train animals to perform tasks of such complexity. Taking advantage of high-throughput training and experimental techniques, we trained rats to perform a task requiring flexible selection and integration of sensory evidence, and applied electrophysiology and optogenetics to study the role of frontal regions during this behavior. Recording from frontal orienting fields (FOF) and medial prefrontal cortex (mPFC), we find highly heterogeneous activity in single cells, consistent with previous reports. Preliminary analyses of population activity suggest that task-context and choice information are encoded in both regions, although with different time courses. Taken together with behavioral analysis and modeling, the findings of this work present a frontier for the study of neural circuits underlying context-dependent decision making.