Sensory Communication

Contains table of contents for Section 2, an introduction, reports on nine research projects and a list of publications.National Institutes of Health Grant 5 R01 DC00117National Institutes of Health Grant 2 R01 DC00270National Institutes of Health Grant 1 P01 DC00361National Institutes of Health Grant 2 R01 DC00100National Institutes of Health Grant FV00428National Institutes of Health Grant 5 R01 DC00126U.S. Air Force - Office of Scientific Research Grant AFOSR 90-200U.S. Navy - Office of Naval Research Grant N00014-90-J-1935National Institutes of Health Grant 5 R29 DC0062

Sensory Communication

Contains table of contents for Section 2, an introduction, reports on ten research projects and a list of publications.National Institutes of Health Grant 5 R01 DC00117National Institutes of Health Grant 5 R01 DC00270National Institutes of Health Grant 5 P01 DC00361National Institutes of Health Grant 2 R01 DC00100National Institutes of Health Grant 7 R29 DC00428National Institutes of Health Grant 2 R01 DC00126U.S. Air Force - Office of Scientific Research Grant AFOSR 90-0200U.S. Navy - Office of Naval Research Grant N00014-90-J-1935National Institutes of Health Grant 5 R29 DC00625U.S. Navy - Office of Naval Research Grant N00014-91-J-145

A Comparison of Auditory and Tactual Presentation of a Single-Band Envelope Cue as a Supplement to Speechreading

Research on auditory supplements to speechreading has clearly demonstrated that even highly simplified auditory signals can lead to substantial improvements in intelligibility. In general, the effects observed with such auditory supplements are greater than those typically observed with tactual aids to speechreading. The purpose of the current study was to compare benefits to speechreading of a supplementary low bandwidth signal presented through either the auditory or tactual system. The supplementary signal, which consisted of a 200 Hz carrier amplitude modulated by the envelope of an octave band of speech centered at 500 Hz, was presented through a high- performance single-channel vibrator for tactual stimulation or through headphones for auditory stimulation. Performance of normal-hearing subjects on the reception of words in sentences and the reception of several suprasegmental properties was examined under conditions of speechreading alone and speechreading supplemented by either the auditory or tactual signal. Benefits to speechreading were observed with both the auditory and tactual supplements for the reception of words in sentences. The size of the benefit observed with the tactual signal was roughly one-third of that observed with the auditory signal. In suprasegmental tests of the ability to discriminate rising from falling pitch contours and the location of the stressed word in a short phrase, neither the auditory nor tactual supplement resulted in improvements in performance over speechreading alone. Possible explanations for the differential effects obtained for auditory and tactual presentation of the same envelope cue are discussed

Effects of Bilingualism, Noise, and Reverberation on Speech Perception by Listeners with Normal Hearing

This study compared monosyllabic word recognition in quiet, noise, and noise with reverberation for 15 monolingual American English speakers and 12 Spanish-English bilinguals who had learned English prior to 6 years of age and spoke English without a noticeable foreign accent. Significantly poorer word recognition scores were obtained for the bilingual listeners than for the monolingual listeners under conditions of noise and noise with reverberation, but not in quiet. Although bilinguals with little or no foreign accent in their second language are often assumed by their peers, or their clinicians in the case of hearing loss, to be identical in perceptual abilities to monolinguals, the present data suggest that they may have greater difficulty in recognizing words in noisy or reverberant listening environments