Composed of gray matter, the outer cortex of nerve cells, and white matter, the inner mass of nerve fibers, it has commanded the attention of scientists for centuries. Engineers likewise point to the brain to try to imitate and replicate the human sensory functions for applications to computers, medical equipment, and other engineering systems. The sciences spawned from this imitation include an impressive list, such as, biomedical engineering, biotechnology, neural networks, real-time neural processing and computer vision, to name a few. Dr. John G. Harris is one of many investigators who has dedicated his career to exploring the inner-workings of the brain and applying what he has learned to novel engineering solutions to a variety of problems, some described below. In auditory signal processing, Harris is creating algorithms to model the sound localization and filtering processes that occur in the brain to build more powerful microphones.
Inspirations come from what is known as the cocktail party effect.
Or, if you wanted to, without even moving your head, you could listen to another conversation. Inspired by this observation, Harris and his colleagues, Dr. Jose Principe and graduate student Chiang-Jung Pu, are working to create the seeming paradox of a stereo recording with a single microphone. By placing a surface behind the microphone to reflect sounds off the back of it, the recorder will pick up both the original sound and its reflection. Based on the computed time delay between the original sound and the delayed sound, Harris can determine from what angle the sound is coming. The microphone could therefore localize incoming sounds, which could be played back in stereo by creating two streams of sound.