SOUND SCIENCE: Nandhu Radhakrishnan, a speech language pathologist, is working to help us sound better.
back as anybody could remember, Nandhu Radhakrishnan's family had produced physicians who proudly served the citizens of India's Tamil Nâdu state. Radhakrishnan's father, grandfather, and great-grandfather all devoted their lives and careers to the healing arts.
So when young Nandhu suggested that perhaps a career in drama and music was his true calling, it's not hard to imagine the stir that broke out in the Radhakrishnan household. "In India, it's a tradition that parents will -- not force -- but try to decide their children's career direction. We were told to focus on -- we were steered toward -- science, medicine, those sorts of disciplines."
Luckily for Radhakrishnan, now a 35-year-old assistant professor at MU, compromise was easy. Because his father was a surgeon who specialized in treating the throat and vocal cords, Radhakrishnan decided to pursue his interest in the arts, music especially, by studying the anatomy and physiology of the human voice, a subject his father was certain to understand and appreciate.
"One of the subspecialities in speech and hearing science is to treat professional voice users," Radhakrishnan recalls with a shrug and smile. "And since that tied in closely to my interest of being an actor, singer, director or playwright, I thought, 'Yes, this is it!' And I pursued it with passion, lots of passion."
After receiving bachelor's and master's degrees in audiology and speech pathology at India's prestigious Mumbai University, Radhakrishnan followed that passion to Ohio's Bowling Green State University, where he earned a doctorate in the lab of renowned acoustician and voice scientist Ronald Scherer.
With Scherer, he investigated the speech mechanisms of classical singers, asking basic but still unanswered questions: How might the lungs, larynx, vocal tracts and articulators of a master vocalist differ from those of us who struggle to carry a tune? What other factors might affect the range and quality of human sound? And, most crucially, how might answers to these questions improve treatments for those with speech pathologies?
"Dr. Scherer channeled my study into learning how the voice can change and how one can improve voice with exercises," Radhakrishnan says. "We were looking into the physiological properties of exercise and how muscles react to exercise; how human beings learn [speech] behavior and how we can affect learned behaviors."
Radhakrishnan is still exploring these issues, now in the Laryngeal Physiology Lab he came to MU in 2005 to establish. Courted by other institutions that wanted labs of their own, he says he chose the University for personal as much as professional reasons.
"To be productive in a work environment you don't necessarily need state-of-the-art equipment or even a tremendous amount of funding. You need collegial co-workers," he says. "That was the first thing that impressed me during my interview. Everyone talks to each other here."
With Radhakrishnan, conversation often centers on happenings in his lab, a linoleum-floored, 300-square-foot room that resembles a low-fi recording studio. Radhakrishnan's desk, computer monitors and mic stands vie for space with bundled wires, audio cords and an array of digital and analog metering devices. There is even an electric piano tucked into the corner.
Keyboard aside, these instruments are all intended to further an elusive goal: determining exactly which organs and muscles are at work, and at what level, when someone speaks or sings. "Voice production is interesting in that two people could be creating the same sound while singing entirely differently. One way may be good, and the other harmful," he says.
Because not every person uses organs and muscles to produce sound in the same way, pinpointing the mechanics of voice requires some highly specialized gear. Sensors used in a process called multiple signal acquisition, to cite just one example, allow Radhakrishnan to measure even minute variations in rib cage and abdominal function during a respiratory and vocal vibratory cycle, thus determining whether variations of air pressure and flow might be the culprits behind a singer's "weak" vocal output.
"If the lung pressure is really high, and airflow is very low, we can tell that the problem is somewhere at the valve level or the vocal chord level," says Radhakrishnan. Having located the source of the problem, he can then seek to correct it using voice exercise and other therapy techniques.
Radhakrishnan's instruments also allow him to visually represent, using waveforms, sounds that singers produce during lessons.
"What interests me is what is happening between the teacher and the student," he says. "We're telling the student, this is what you are doing, this is how the voice is sounding, and this is what it looks like on a graph. This may give several avenues of feedback, or give several channels of bio-feedback, that may help learning occur faster, or otherwise enhance the student's learning."
And his own singing and acting? Radhakrishnan says he still loves music and drama, and that he's active, along with his speech-pathologist wife, in local events celebrating India's rich culture. But he's not planning to quit his day job: "Since I realize I'm not that good at singing -- that I'll never have a professional's voice -- I think I'm able to understand the limitations most of us face, as well as better admire what those special few have and work on the science behind it."