Effects of Hearing Impairment on Neural Encoding of Speech in Awake-Behaving Mammals

Interdisciplinary Areas: Engineering and Healthcare/Medicine/Biology

Project Description

Understanding speech can be difficult in everyday noisy listening environments, such as restaurants. For hearing-impaired listeners, background noise is particularly troublesome. Approximately 40 million US adults are affected by noise-induced hearing loss: the most common form of preventable cochlear damage. Understanding the physiological basis of robust neural coding of speech in normal auditory systems, and the coding deficits resulting from cochlear damage, is critical for the development of effective audiological diagnostic tools and therapeutic interventions for these patients.
Studies quantifying the impact of noise-induced cochlear damage on neural coding of complex sounds in animals have typically used anesthetized animals. Since anesthesia is known to disrupt normal auditory neural coding, the translational relevance of those data is limited.
We will quantify the neural coding and behavioral discrimination of the acoustic parameters important for speech perception in noisy environments in awake-behaving chinchillas. Using novel wireless implantable recording technology developed at Purdue, we will obtain simultaneous single-neuron responses from the cochlear nucleus and whole-animal behavioral responses. Using innovative systems-identification analyses and signal-detection-theoretic approaches, we will directly compare animals’ neurometric and psychometric performance before and after noise-induced hearing loss. These awake-behaving neural data will inform future developments in audiological diagnostic and therapeutic clinical practice. 

Start Date

Spring 2019

Postdoc Qualifications

PhD in neuroscience, biomedical or electrical engineering, computational modelling, hearing sciences, or any other area related to sensory neuroscience and auditory signal processing. 


Michael G. Heinz, PhD (Professor of Speech, Language and Hearing Sciences); mheinz@purdue.edu; https://engineering.purdue.edu/auditory/

Mark Sayles, MD PhD (Assistant Professor of Biomedical Engineering); saylesm@purdue.edu; https://engineering.purdue.edu/SaylesLab 


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