Interfacing Neuronal Cultures to a Computer Generated Virtual World

Neural encoding consists of the transformation of information from one representation (e.g., sensory input from neural connections to the eyes, ears, etc.) into another (a neural code). There has been a great deal of effort in the past to understand how such information is both processed and encoded by the brain. To date, most of what we have learned about the neural basis of information processing is based upon recordings from single neurons. However, beginning in the 1970's with the development of multi-electrode array (MEA) technology (e.g., Thomas et al. 1972; Gross, 1979; Pine, 1980) the possibility of detailed study of the activity of entire populations of neurons became possible. This ability has led to a rapid expansion of researchers interested in investigating the properties of information processing and neural encoding of distributed neural activity in brains, slices, and dissociated neural cultures. However, while implanted MEAs allow one to study intact neural tissue in the brain, the lack of accessibility makes it difficult to perform simultaneous detailed studies of the underlying morphological structures. Conversely, studying neural tissue in culture allows highly detailed study through extracellular, patch clamp, or standard microscopy techniques. The disadvantage is that these cultures now lack any meaningful sensory input or the means to produce any sort of behavioral output. Therefore, it is difficult to associate the changes in morphology that can be observed with these techniques with the changes in behavior that occur as a result of experience within an intact brain.