Ramnarayan (Ram) Ramachandran
Assistant Professor of Hearing and Speech Sciences
We are interested in the question of how we hear and process sounds in noisy, natural environments. These situations are important because they reflect precisely the kinds of circumstances that older people and people with hearing impairment have great difficulty in navigating. And moreover, the ability to hear in noisy environments, which is effortless for people with normal hearing, can not be restored to people with hearing difficulties through hearing aids or cochlear implants. Our initial (current) studies deal with the normative baseline. What is the neuronal basis for being able to hear in noisy environments for normal hearing? We investigate this with a combination of behavior, neurophysiology and computational modeling. We use behavioral methods to measure hearing metrics in quiet environments, and how these metrics are modified in noisy environments. Electrophysiological tools allow us to directly correlate the report of hearing and the hearing metrics with neuronal activity in different parts of the brain. We can then through computational modeling and clever experimental design infer the auditory circuitry that could be involved in the behavior. These experiments that we currently perform can (and will) be extended to other aspects of behavior (such as telling the difference between sounds, telling where or what the sound is, etc.) for us to investigate the mechanisms and circuits underlying them. However, these just form the baseline for our scheduled future studies of hearing after hearing loss, and the ability to hear and process sounds in natural, noisy environments. Our long-term goal is to design assistive-hearing devices that can function equally well in noisy or quiet environments based on the results that we obtain.