David Martinelli, Ph.D.
Meet the Researcher
Martinelli received his doctorate in developmental biology from Johns Hopkins University and the Carnegie Institution for Science. He completed postdoctoral training at Stanford University and is now an assistant professor of neuroscience at the University of Connecticut Health Center. His 2019 Emerging Research Grant was generously funded by Hyperacusis Research Ltd.
As a postdoc I studied a gene called C1q-like 3 in the brain. I showed it was important in allowing neurons to communicate with one another in the brain. In 2014, a paper suggested that the gene C1q-like 1, in the same family, was important in the cochlea’s sensory hair cells. At the time, I didn’t even know what hair cells were, so I sat on this publication for years. Then it was serendipitous that the neuroscience department where I am an assistant professor has long studied the auditory system. We could combine my expertise and tools to study C1q-like genes with experts on the auditory system.
As we looked more closely at this gene, we realized that it may have a function in the detection of auditory pain. Hyperacusis is a condition in which a person experiences pain at a much lower volume level than listeners with typical hearing. Using a novel animal model in which this gene that is part of the pain circuit is missing, we hypothesize it will lessen the perception of auditory pain when high intensity sounds are presented.
For a science project when I was 14, I built a 6-foot-by-10-foot maze and ran my pet hamsters through to get a food reward at the end. The little critters did indeed improve their maze running time. My mother says after all these years that I am still playing with rodents, which is quite true.
In a high school genetics glass, I remember separating fruit flies whose genes made their eyes different colors. I loved it and majored in molecular genetics in college. In graduate school I joined the lab of Chen-Ming Fan, Ph.D. We studied a gene called sonic hedgehog (known as SHH, and not to be confused with Sonic the Hedgehog). Like a second father to me, Dr. Fan showed me how to mentor (we are still close), and I now consider teaching the students in my lab to be a sacred responsibility.
David Martinelli, Ph.D., is funded by Hyperacusis Research Ltd. We thank Hyperacusis Research for its support of studies that will increase our understanding of the mechanisms, causes, diagnosis, and treatments of hyperacusis and severe forms of loudness intolerance..
The Research
University of Connecticut Health Center
Creation and validation of a novel, genetically induced animal model for hyperacusis
Hyperacusis is a condition in which a person experiences pain at much lower sound levels than listeners with typical hearing. While the presence of outer hair cell afferent neurons is known, it is not known what information the outer hair cells communicate to the brain through these afferents. This project’s hypothesis is that the function of these mysterious afferents is to communicate to the brain when sounds are intense enough to be painful and/or damaging, and that this circuitry is distinct from the cochlea-to-brain circuitry that provides general hearing. The hypothesis will be tested using a novel animal model in which a certain protein that is essential for the proposed “pain” circuit is missing. The absence of this protein is predicted to cause a lessening of the perception of auditory pain when high-intensity sounds are presented. If true, this research has implications for those suffering from hyperacusis.
Long-term goal: To take advantage of the molecular mechanisms of the outer hair cell afferents and develop methods to dampen the perception of auditory pain, providing relief to those with hyperacusis without affecting traditional hearing.