At an age when her school chums were learning to ride bikes, Radha Kalluri busied herself taking apart appliances in her family’s Boston home. Blenders, calculators and vacuum cleaners – no electrical device was safe from young Dr. Kalluri’s agile fingers and inquisitive mind.

Now, as one of our newest researchers, Dr. Kalluri is studying the mechanics of one of nature’s most elegant and mysterious devices: the inner ear. Her work focuses on understanding the mechanical and cellular processes of the inner ear – the sensory structure responsible for hearing and balance. “When these systems are functioning properly, we don’t think very much about them,” she says. “But when something goes wrong with either hearing or balance, it can be very debilitating and quickly becomes a quality-of-life issue.”

 In one aspect of her work, Dr. Kalluri is improving on the precision of non-invasive measurement techniques to study the mechanics and physiology of the cochlea in humans. One goal of the research is to develp tests in humans that can correlate the physiology (how well the cochlea is working) with hearing performance (the ability to hear). Existing tests measure only one or the other.

 “We are missing tests that say: It looks like you have normal hearing based on tests, and here’s how that relates to your hearing performance,” Dr. Kalluri says. “How well do you hear in an actual hearing environment? And what do these separate results mean in terms of your ability to hear?”

As an example, working with HRI’s Dr. Caroline Abdala, an expert in the development of hearing in infants, Dr. Kalluri has developed a tool that improves the precision of otoacoustic emissions (OAE) testing, a non-invasive means of measuring the function level of the inner ear. She is now using one such measurement technique to examine possible changes in the sharpness of tuning in the developing cochlea.

“Tuning is the measure that allows you to distinguish between the vowels of “ah” and “e” or two notes next to one another on the piano,” Dr. Kalluri says. “The sharper your tuning is, the finer your ability to distinguish small differences in frequency – vital to understanding speech and fully hearing music.”

Dr. Kalluri is hoping that the development of these more precise measurement techniques will eventually lead to assessment tools that can more precisely identify the type and source of hearing loss.

 Dr. Kalluri was born in India and moved with her family to Boston at age seven. Her love of tinkering led her to the University of Massachusetts at Amherst, where she earned a bachelor’s degree in engineering. “I liked the combination of theoretical and hands-on elements that engineering offers,” she says. While pursuing a master’s degree in electrophysics at the University of Southern California, she read an article on retinal implants being developed for the blind by teams of engineers and physicians. The article inspired her to apply her engineering skills to the biological sciences.

Dr. Kalluri soon discovered that the auditory system was an excellent area for study. “If you are interested in understanding how different processes allow you to sense the environment, the inner ear has a beautiful structure,” she says. “It has both a mechanical structure and a beautiful neural network and feedback mechanisms that in many ways make it a model system for study.”