![Sample our Health and Social Care journals, sign in here to start your FREE access for 14 days]({"type":"image" , "src" : "/sda/5938/TOC-Subject-Sample-2021-Health-Social-Care.jpg"})
Abstract
In providing profoundly hearing-impaired persons with processed speech through a signal-processing hearing aid, it is important that the new speech code matches their auditory capacities. This processing capacity for auditory information was investigated in this study. In part 1, the subjects’ ability to judge similarities among 8 different but related harmonic complexes was studied. The patterns contained different numbers of harmonics to a 125-Hz fundamental frequency; the harmonics had been spread over the spectrum in various ways. The perceptual judgments appeared to be based on a temporal cue, beat strength, and a spectral cue, related to the balance of high and low frequency components. In part 2, three sets of synthetic vowels were presented to the subjects. Each vowel was realized by summing harmonically related in-phase sinusoids at two formant frequencies. The sets differed in the number of sinusoids per formant: 1, 2 or 3. It was found that the subjects used spectral cues and vowel length for differentiating among the vowels. The overall results show the limited but perhaps usable ability of the profoundly impaired ear to handle spectral information. Implications of these results for the development of signal-processing hearing aids for the profoundly hearing impaired are discussed.