Perception of normal and spectrally compressed speech by the skin

Abstract

The development of sensory aids continues to be focused on increasing the number of channels and on alternative processing schemes. The present study compares natural hVd syllables and simple sentences presented with varying degrees of spectral compression [R. Hurtig, J. Acoust. Soc. Am. Suppl. 1 85, S44 (1989)] under vibrotactile and electrocutaneous stimulation conditions. In addition, a comparison of the number of channels used was made. Confusion matrices were constructed from the responses made in a closed set identification task, which followed a subject‐paced exploratory learning task. Multidimensional scaling of the stimuli based on their first three formant values produced the standard representation against which the perceptual data could be evaluated. This congruence analysis graphically illustrates the distortions of the perceptual vowel space. An overall shrinkage of the perceptual space is evident across conditions; however, this effect is not uniform. Warping of the space is observed but in different portions of the space for each of the stimulation conditions.