As we age our ability to understand speech often gets worse, especially in noisy environments. Sometimes this happens even though routine audiological tests turn out to be fine. The causes of these age-related hearing difficulties in the absence of a clinical hearing loss are not fully understood. These hearing difficulties may be due to a partial loss of the nerve fibers responsible for transmitting sound signals, or to subtle changes occurring to these nerve fibers. We are conducting an experiment that aims to clarify the causes of age-related hearing difficulties. This is a fundamental step towards developing early diagnosis and treatment of age-related hearing difficulties. A more in depth summary of this research project is provided here.
The experiment consists of a battery of auditory, electrophysiological, and cognitive tests. These include: – Discrimination and identification of speech and non-speech sounds presented through headphones (e.g. detecting which of two sounds has a higher pitch, or identifying a word in a noisy background). – Tests of cognitive performance (e.g. ability to memorize sequences of digits of increasing length). – Recordings of electroencephalographic (EEG) responses to sounds. EEG recordings measure the tiny currents generated by the brain through electrodes placed on the scalp.
We have now completed collecting all the data for the experiment and we are in the process of analyzing the data and writing up the results for publication.