Research

Dr. Murray’s laboratory studies the neural basis of learning, memory, emotion and behavior, with two main areas of focus: memory systems and value-based decision-making. The research on memory systems has demonstrated that each of the cortical areas in the so-called “medial temporal lobe” perform distinct functions based on their specialized neural representations. For example, some types of memory depend on the entorhinal and perirhinal cortex and not on the hippocampus. Furthermore, contrary to the idea that some cortical areas specialize in memory, whereas others specialize in perception, evidence from the laboratory’s work has shown that each area’s specialized representations supports both memory and perception.

Studies of decision-making examine the neural circuits critical for valuations that guide the selection of objects and actions, including choices based on affective information and predicted rewards. This research examines the functional interactions among three components of the limbic system: the amygdala, orbitofrontal cortex and medial prefrontal cortex. Using behavioral analyses combined with structural and functional magnetic resonance imaging, single-unit recording, and both permanent and temporary brain manipulations, this work has shown that the amygdala and orbitofrontal cortex cooperate to update the subjective valuations that guide decision-making. Current work focuses on the selective contributions of different prefrontal cortical regions in promoting advantageous choices.