Medicine and Health Sciences Commons^™

Effects Of Hearing Aid Amplification On Robust Neural Coding Of Speech, Jonathan Daniel Boley

Open Access Dissertations

Hearing aids are able to restore some hearing abilities for people with auditory impairments, but background noise remains a significant problem. Unfortunately, we know very little about how speech is encoded in the auditory system, particularly in impaired systems with prosthetic amplifiers. There is growing evidence that relative timing in the neural signals (known as spatiotemporal coding) is important for speech perception, but there is little research that relates spatiotemporal coding and hearing aid amplification.

This research uses a combination of computational modeling and physiological experiments to characterize how hearing aids affect vowel coding in noise at the level of …

Predicting Language Impairment Status: A Risk Factor Model, Johanna Maria Rudolph

Open Access Dissertations

The etiology of specific language impairment (SLI) is multifactorial. Research has shown that genetic, environmental, and developmental factors may influence the course of its development. Because many of these factors are present even before a child is born, it is possible that a child's risk of developing the disorder can be identified long before grammatical deficits are observed. The goal of this study was to develop and validate a screening tool to discriminate between children with SLI and typically developing (TD) children using risk factor information including gender, family history of communication or reading disorders, socioeconomic status, maternal and paternal …

Patient Perceptions Of Physicians And Medication Adherence Among Medicare Part D Beneficiaries, Lori Marquinne Ward

Open Access Dissertations

Ward, Lori Marquinne. Ph.D., Purdue University, December, 2013. Patient Perceptions of Physicians and Medication Adherence Among Medicare Part D Beneficiaries. Major Professor: Joseph Thomas III.

An observational database analysis using Medicare Current Beneficiary Survey data was conducted to examine patient perceptions of physicians and associations with adherence to antihypertensive medication among Medicare beneficiaries enrolled in Medicare Part D. The study sample included beneficiaries if they were 65 years or older, dwelling in the community, had a diagnosis of hypertension in 2007, were enrolled in Medicare Part D all 12 months in 2008, and had Medicare Part D claims for antihypertensive …

Neural Encoding Of Complex Signals In The Healthy And Impaired Auditory Systems, Saradha Ananthakrishnan

Open Access Dissertations

Individuals with sensorineural hearing loss (SNHL) typically experience difficulty in understanding speech. Our current knowledge of deficits in speech perception and encoding consequent to SNHL is restricted to psychophysical studies in humans and single-unit experiments in animals. However, the nature of degradation in neural encoding of speech following hearing impairment in humans has not been extensively researched. The objective of this dissertation is to provide a systematic evaluation of neurobiological signature of hearing loss at the subcortical level using an objective electrophysiological non-invasive neural index, the frequency following response (FFR). Subcortical neural encoding of speech signals is explored by quantifying …