Although new auditory evoked potential equipment was ordered late summer of 1987, delivery was not made until mid-April 1988. Dichotic studies using the digits test of Musick in normally aging and demented subjects did continue during that time (approximately 90 subjects were seen). Data collection is ongoing for the Dichotic Digits tests in these populations. Since mid-April of 1988, 26 subjects have been seen for gathering normative auditory brainstem response (ABR), data on our new auditory evoked potential equipment. Data is gathered at frequently used stimulus intensities, stimulus polarities, stimulus rate, and by age and sex. All of these conditions are studied using both circumaural and insert earphones. We are looking forward to also collecting data on insert electrodes should we be able to free up enough clinic time. It is essential that we continue to see as many normals as possible in order to be able to use our new auditory evoked potential equipment on our diverse patient populations as soon as possible. The insert earphones will provide even more comfortable testing conditions for many patients previously unable to tolerate heavy earphones or in whom myogenic artifact was a serious containment. Multi-frequency immittance norms will be collected as time permits. The software is still evolving and we anticipate data collection to begin in the fall of 1988. These studies will be helpful in evaluating the middle ear systems in patients with connective tissue disorders. It is pertinent to note that the Audilogy Clinic is primarily a service consultative facility, and the needs of the NIH patients always come first. Therefore, we see normal controls for this study only when there is no conflict with patient scheduling in Audiology.
