Our laboratory research interests center around the brain's "executive" functions. We study the neural mechanisms of attention, learning and memory needed for voluntary, goal-directed, behavior. Much effort is directed at the prefrontal cortex, a cortical region at the anterior end of the brain that has long been known to play a central role in high-level cognitive function. Prefrontal damage or dysfunction disrupts our ability to ignore distractions, hold important information "in mind", plan behavior, and control impulses. We explore prefrontal function largely by combining a sophisticated behavioral methodology with techniques for examining the activity of groups of single neurons.
Results from our laboratory
have shown that neurons in the prefrontal cortex have complex properties that
seem ideal for a region thought to be the brain's executive. They are involved
in directing attention, in recalling stored memories, in categorizing objects,
and they piece together the diverse information needed for a common behavioral
goal. Perhaps most importantly, they transmit acquired knowledge. Their activity
reflects the learned associations between cues, actions, and consequences
that describe the contingencies of a given task; they can even communicate
information about abstract concepts such as "sameness" or "difference".
In short, the prefrontal cortex seems to provide a neural substrate for the
representation of the important information and "rules of the game"
that are needed to guide thought and action. This may provide the necessary
foundation for the complex behavior of primates, in whom this structure is
In a recent experiment from Earl Miller's laboratory, monkeys were trained to categorize computer generated "morph" images into two classes, "cats" and "dogs". It was revealed that the process of category learning caused single neurons in the prefrontal cortex to become categorically tuned.
Professor, Department of Brain and Cognitive Sciences
Associate Director, Picower Center for Learning and Memory
Investigator, RIKEN-MIT Neuroscience Research Center
Earl K. Miller
received his Ph.D. in Psychology and Neuroscience from
Princeton University. After postdoctoral training at the National Institute of Mental Health, he joined the Department of Brain and Cognitive Sciences
and the Picower Center for Learning and Memory at MIT in 1995. He is a
recipient of numerous scientific awards, including the Pew Scholar Award,
McKnight Scholar Award,
an Alfred P. Sloan Fellowship, John Merck Scholar Award, the National Academy of Sciences Troland Research Award, and the Society for Neuroscience Young