Active Research

Principal Investigators: Nancy Vaughan, PhD, Stephen Fausti, PhD

Objectives: The purpose of the proposed study is to investigate the processing of verbal communication in veterans with and without diabetes.

Research Plan: Four hundred diabetic and non-diabetic patients (200 in each group) from the Portland VA Medical Center will participate. Patients will have normal hearing or hearing loss no worse than 40 dBHL at 2000 Hz and 70 dBHL at 4000 Hz.

Methods: Speech understanding will be evaluated using two types of modified speech recognition tests that will increase processing demands in different ways: speech in noise and time-compressed (rapid) speech. A battery of psychoacoustic, neurocognitive and neurophysiological tests associated with speech understanding deficits will also be administered. Data analysis will compare diabetic and non-diabetic veterans on the results of these tests where age, hearing loss, and comorbidity are covariates. Correlational analyses will be performed to determine which results from the test battery are associated with processing deficits in verbal communication.