The program started in 1980 has evolved into the current Section on Neural Coding and Computation. This group has studied the coding visual stimuli by as a model for higher brain functions such as perception, memory and motivation. The earliest work was into the influence of focal attention on neural activity. In the early 1980's this group showed that the visual receptive fields of temporal lobe neurons changed their sizes under different attentional requirements. A long term and ongoing project to learn how information is coded by single neurons grew out of this work. Recently their understanding of neural codes has advanced enough so that they have a nearly perfect description of the complexities of neural firing, accounting for almost all of the variability within single neuronal activity. On a practical level this has led to a real-time decoding algorithm that decodes single neuronal firing accurately enough instant-by-instant to translate activity into the commands needed to drive a prosthetic device. Over the past ten years, the section has also been studying neural processes underlying normal motivation and reward expectancy. Specifically, how information about the identity of a visual stimulus is transformed into information about stimulus meaning for reward expectancy, i.e., how does the brain learn to use visual cues to predict the future the outcome of a sequence of behavioral tasks. This work has grown tremendously over the past five years as they have been able to show that a large number of brain regions, ventral and dorsal striatum, and rhinal, insular, and cingulate cortices have signals related to how many trials must be carried out to obtain a reward or reach a goal.  Dr. Richmond’s section has recently shown that the rhinal cortex is necessary for associating visual stimuli with predictions of reward expectancy. In an extremely promising technical advance, they have developed a molecular approach (using antisense technology) to use in monkeys. With this approach, they have shown that the D2 receptor in rhinal cortex is critical for forming these associations. This molecularly based approach provides a powerful means to connect molecular events with neural codes and behavior. This line of work will provide new insight into how normal motivation arises, and, how motivation might be disrupted in both intrinsic and acquired disorders, e.g., OCD and drug abuse. This approach has the potential for developing into a method to test molecular therapies on a temporary basis, and with a small extra manipulation these could be made permanent when needed.

• Shidara, M and Richmond, BJ; Anterior cingulate: single neuronal signals related to degree of reward expectancy. Science, 296(5573):1709-11, 2002.
• Oram, MW, Hatsopoulos, NG, Richmond,BJ, and Donoghue, JP: Excess synchrony in motor cortical neurons provides redundant direction information with that from coarse temporal measures. J Neurophysiol., (4):1700-16, 2001.
• Wiener, MC, Oram, MW, Liu, Z and Richmond, BJ: Consistency of encoding in monkey visual cortex. J Neurosci,21(20):8210-21, 2001.
• Liu,Z, Murray, EA, and Richmond, BJ: Learning motivational significance of visual cues for reward schedules requires rhinal cortex. Nat Neurosci, 3(12):1307-15, 2000.
• Liu, Z and Richmond, BJ: Response differences in monkey TE and perirhinal cortex: stimulus association related to reward schedules. J Neurophysiol, 83(3):1677-92, 2000.