The mission of the MacLean laboratory is to understand how the brain encodes and stores information. The MacLean lab is multidisciplinary, combining biology and mathematics, and provides a rich training environment for neuroscientists of the future. In addition to the training and mentoring of both graduate and undergraduate students, Dr. MacLean is actively promoting scientific literacy through outreach programs including training opportunities within his lab for underrepresented groups and is also using his data in a course on advanced topics and methods in computational neuroscience. Using state of the art laser microscopy the MacLean lab films groups of neurons in the brain in action, allowing for the investigation of neuronal circuits. In the same way that an electrical circuit is formed by connecting simple components, a neural circuit is formed by its component neurons and the connections between them. It has long been known that single neurons work as part of larger circuits but only recently have the tools been available to investigate large populations of neurons at the same time. MacLean and co-workers recently showed that each neuron is co-active with a group of other neurons and that activity flows from group to group in an orderly and often repeating sequence. These organized circuit patterns are analogous to the scrolling text in Times Square, New York City. While no single light can convey even a single word, the array of lights can convey a full phrase or sentence through their patterned activity. Similarly, no single neuron can communicate the full information in a neural circuit on which the brain relies for its functioning. A fundamental, though often unspoken hypothesis in neuroscience is that information is coded by patterns of activation within circuits -- a question which the MacLean lab is investigating. Researchers also postulate that these spatiotemporal circuit patterns are a result of the specific connectivity between the neurons. Thus these patterns can be considered an elementary functional unit of information processing in the brain and simultaneously can reveal the underlying structure of brain circuits. Using data from many circuits the MacLean lab will uncover the basic circuit composition rules of the sensory cortex. For instance this work will reveal how many circuits are present in a patch of the sensory cortex containing a set number of neurons, a very basic question for which there still is no answer. Further the MacLean lab will mathematically show how information is represented by patterned circuit activations. Finally these researchers will determine the biological mechanisms which produce these patterns. These are fundamental questions critical to our understanding of cognition, learning, memory and behavior. The MacLean lab will provide substantial broader impacts by introduction of his research program into the experimental approaches taught in a course on computational neuroscience. In addition, Dr. MacLean will initiate a new Science and Technology program to show demonstrations of his work to girl scouts, in the hope of increasing participation of women and minorities in science.
