Johnson Lab Research
The Johnson Lab at NYU Langone studies the voice by encompassing a variety of techniques and approaches to conduct multifaceted research analyzing both rodent and human systems, with the goal of understanding, preventing and treating voice disorders in older adults.
Investigating laryngeal neuromuscular mechanisms directly in humans is challenging due to the small size and relative inaccessibility of the intrinsic laryngeal muscles. Therefore, we have focused on an animal model for our translational research. The ultrasonic vocalizations (USVs) of rats have been used in behavioral neuroscience to study a variety of correlates between the brain and behavior. Because rats create USVs using the same laryngeal muscles as humans use to vocalize and because rats can be trained to increase how much they vocalize, USVs provide an opportunity to study the relationship between vocal training and underlying laryngeal neuromuscular mechanisms.
Dr. Johnson pioneered the application of this model in a 2013 vocal training study in which he explored the effect of USV training on both vocal behavior and neuromuscular plasticity in the senescent rat larynx. Old rats that were trained to increase their USV production over eight weeks had reduced age-related changes in both USV acoustics and laryngeal neuromuscular junction morphology relative to an untrained control group. The team’s current research, funded by the National Institutes of Health, is expanding on these findings by refining the type, length, and intensity of the vocal intervention as well as exploring how vocal exercise affects mechanisms of muscle hypertrophy. Additional work is focused on automating the vocal training system to improve consistency and increase training intensity and throughput and in applying high-throughput metabolomic and proteomic methods to more fully characterize the effects of age and exercise on the laryngeal muscles.
One area that holds great promise for improving the aging voice is singing training through choir participation. Choir singing has been used as a treatment program for diseases such as chronic obstructive pulmonary disease, dementia, and Parkinson’s disease. Despite this precedent, there is little existing research on the effects of singing and vocal training in older adults. Our research examines the effects of vocal training in older adults through choir participation using traditional clinical acoustic and aerodynamic measures of vocal function, as well as novel high-resolution three-dimensional MRI to measure changes in laryngeal structure related to aging and vocal exercise.
Related Areas of Vocal Research Interest
We are curious about a variety of issues pertaining to the singing voice, such as the physiology of belting, as well as extreme capabilities of the laryngeal mechanism, like those involved in beat-boxing. In addition, we are involved in several exciting endeavors to test the use of new technologies to monitor vocal load and assess virtual vocal training.