Research efforts in the Polley Lab are directed toward understanding the mechanisms and clinical implications of brain plasticity. Auditory brain plasticity exhibits a fundamental duality, a yin and yang, in that it is both a source and possible solution for various types of hearing impairments. Following hearing loss, the balance of excitation and inhibition tips toward hyperexcitability throughout auditory processing regions of the brain to compensate for the loss of input from the ear.

 Dr. Polley’s work has shown that central gain cannot fully compensate for the loss of cochlear afferent neurons. To the contrary, hyper-amplification in the brain can further distort the neural representation of complex communication sounds, such as speech in noise, and even induce the perception of phantom sounds, contributing to pathophysiological processes such as hyperacusis and tinnitus.

This is the "yin," the dark side of brain plasticity, wherein the transcriptional, physiological and neurochemical changes that compensate for the loss or degradation of peripheral input can incur debilitating perceptual costs. The Polley Lab is also committed to understanding the "yang" of brain plasticity—how the remarkable malleability of the adult brain can be harnessed and directed towards an adaptive, or even therapeutic, endpoint through pharmacology, direct brain stimulation and non-invasive approaches such as immersive sensory training.

In the Polley Lab, their ultimate interests lie at the intersection of these two sides of brain plasticity. They are working to identify interventions that will turn down excess central amplification and restore normal auditory perception in individuals with hearing loss. 

The Polley Lab pursues its research interests in animal models and human subjects. Their animal models leverage cutting-edge approaches in optogenetics, in vivo cellular imaging, multi-channel electrophysiology, and behavioral neuroscience to manipulate neuromodulatory systems, identify drug targets and develop auditory training strategies that might shed light on human auditory pathologies. Their human subject work focuses on customized auditory training interfaces, aiming to enhance speech processing in noise and reduce the subjective intensity of tinnitus.

• Polley Lab
• Eaton-Peabody Laboratories
• Lauer Tinnitus Research Center
• Speech and Hearing Bioscience and Technology (SHBT) Program