Our brains excel at all kinds of things, but when neurobiologists and psychobiologists try to reverse engineer certain brain functions in order to produce a machine or system that might mimic some of the brains extraordinary abilities, more often than not they fail (or at least engineer something that isnt half so elegant).
Now, researchers funded by Dr. Harold Hawkins (Program Officer in ONRs Cognitive and Neural Sciences Division) think theyre on to something. By fusing engineering techniques with neurobiology, theyve been able to model mammalian brain function using biologically realistic, highly detailed models of individual brain neurons and their assemblies. They are learning how the architecture and physiological properties of cells in the brain (the primary visual cortex) integrate visual cues for target recognition. In other words how the brain computes.
Right now were building a cellular-level model of a small piece of visual cortex, says Dr. Leif Finkel, head of the University of Pennsylvanias Neuroengineering Research Lab. Its a very detailed computer simulation which reflects with some accuracy at least the basic operations of real neurons. His colleague, Kwabena Boahen, is building VLSI computer chips that reproduce cortical wiring and many of the properties of the cells. He has a chip that accurately models the retina and produces output spikes that closely match real retinae. We hope someday that these can be used as retinal implants.
Weve asked them to take a computational approach to neuroscience, says Hawkins. Theyre looking at object-recognition systems that mimic the brain's ability to find patterns in highly cluttered visual scenes by integrating information derived from bottom-up, top-down and horizontal connections among neurons in the primary visual cortex. Its precisely what the Defense Department is interested in currently, and for obvious reasons can we build systems that can instantly pick out an indivi
Contact: Gail S. Cleere
Office of Naval Research