Temporal rate discrimination training

The goal of this randomized control clinical trial is to evaluate the benefit of auditory training to improve perception of timing information, using a simple, non-speech stimulus.  The study assesses the differences in benefit and time-course of training for three listener groups:  young, normal-hearing listeners, older normal-hearing listeners, and older listeners with hearing loss.  We evaluate benefit using behavioral measures and auditory evoked potentials measures (EEG) to examine the changes in neural encoding in the brain as a result of training.  Listeners in the experimental group receive training with the rapid pulse trains, and their performance is compared to an active control group that receives a different form of training, and a passive control group that receives no training.  Training entails 9, one-hour sessions of listening to the stimuli of interest and making behavioral judgements about differences between them, using a laboratory computer.  All groups undergo extensive behavioral and EEG testing prior to training, immediately following training, and one-month post-training.  The study assesses benefit for the trained stimuli, as well as for untrained stimuli to examine generalization of the training.  
 

Training with rapid sentences

This study evaluates the benefit of experimental training with time-compressed speech for improving perception of rapid speech and other forms of distorted speech. Time-compressed speech is a simulation of naturally fast speech, in which the experimenter can control the rate of the speech signal.  Older people often complain of difficulty understanding the speech of people who talk at a fast rate or who speak with a foreign accent, as well as difficulty understanding noise in poor acoustic environments (noise, reverberation). For this study, listeners are recruited who are young adults with normal hearing, older adults with normal hearing, or older adults with hearing loss.  Listeners undergo 6 training sessions of 1-hour/each, using a laptop in their home.  Listeners participate in either experimental training with the time-compressed (rapid) sentences or in active control training with sentences presented in noise. All listeners are evaluated on an extensive test battery at pre-training, post-training, and long-term retention intervals.  This test battery includes behavioral and EEG measures, using various types of speech signals to measure benefit with trained signals and generalization to untrained signals.  Recruitment is ongoing for this study.