Overview

The Hearing Response Mechanisms through Observations of Neuro-Immunity in the Cochlea (HARMONIC) Laboratory, uses a combination of techniques including fluorescent imaging, flow cytometry, and deep neural network analysis of facial grimace and movement to understand how the immune system and neurons of the cochlea interact after exposure to loud noise. The long-term goal of Dr. Beers Wood’s research is to develop interventions to prevent or treat noise induced hearing loss (NIHL) or NIHL associated conditions such as pain hyperacusis.

Active Research Areas

  • Pain hyperacusis (noxacusis) causes significant impacts on the quality of life of its sufferers who experience normal levels of sound as painful. The mechanism is not known and there is no current treatment. An animal model of pain hyperacusis will help to better understand this condition. First, an assay is needed to reliably demonstrate that an animal is in pain in response to sound (sound-evoked pain).

    We created an assay called BIOMAP: A Behavioral Inventory of Mouse Affective Pain. This assay uses machine learning to quantify the facial grimace, movement and complex behaviors of an animal. Mice exposed to sound at the human pain level (120 dB) demonstrate changes in behavior equivalent to that of the peak of a migraine.

    Since up to 50% of people with pain hyperacusis can recall an instance of loud noise associated with the onset of symptoms, we will use noise exposure to induce hyperacusis. We will then quantify cochlear immune cells and type II afferent neuron synapse morphology.

  • The macrophage response to acoustic trauma has been well documented. However, in other systems, macrophages are only one part of the immune response to tissue damage. We have examined the immune compartment of the inner ear and found type II innate immune cells as one of the dominate immune cell types other than macrophages. The type II immune pathway has been understudied in the ear. The type II response is helpful for wound healing and tissue regeneration but can also be associated with fibrosis. We will continue basic studies into type II responses after acoustic trauma.