Carolyn Richie

Discrimination and identification of vowels by young, hearing-impaired adults

This study examined the effects of mild-to-moderate sensorineural hearing loss on vowel perception abilities of young, hearing-impaired (YHI) adults. Stimuli were presented at a low conversational level with a flat frequency response (approximately 60 dB SPL), and in two gain conditions: (a) high level gain with a flat frequency response (95 dB SPL), and (b) frequency-specific gain shaped according to each listeners hearing loss (designed to simulate the frequency response provided by a linear hearing aid to an input signal of 60 dB SPL). Listeners discriminated changes in the vowels /I e E inverted-v ae/ when F1 or F2 varied, and later categorized the vowels. YHI listeners performed better in the two gain conditions than in the conversational level condition. Performances in the two gain conditions were similar, suggesting that upward spread of masking was not seen at these signal levels for these tasks. Results were compared with those from a group of elderly, hearing-impaired (EHI) listeners, reported in Coughlin, Kewley-Port, and Humes [J. Acoust. Soc. Am. 104, 3597-3607 (1998)]. Comparisons revealed no significant differences between the EHI and YHI groups, suggesting that hearing impairment, not age, is the primary contributor to decreased vowel perception in these listeners.

Vowel perception by noise masked normal-hearing young adults.

This study examined vowel perception by young normal-hearing (YNH) adults, in various listening conditions designed to simulate mild-to-moderate sloping sensorineural hearing loss. YNH listeners were individually age- and gender-matched to young hearing-impaired (YHI) listeners tested in a previous study [Richie et al., J. Acoust. Soc. Am. 114, 2923-2933 (2003)]. YNH listeners were tested in three conditions designed to create equal audibility with the YHI listeners; a low signal level with and without a simulated hearing loss, and a high signal level with a simulated hearing loss. Listeners discriminated changes in synthetic vowel tokens /I e epsilon alpha ae/ when Fl or F2 varied in frequency. Comparison of YNH with YHI results failed to reveal significant differences between groups in terms of performance on vowel discrimination, in conditions of similar audibility by using both noise masking to elevate the hearing thresholds of the YNH and applying frequency-specific gain to the YHI listeners. Further, analysis of learning curves suggests that while the YHI listeners completed an average of 46% more test blocks than YNH listeners, the YHI achieved a level of discrimination similar to that of the YNH within the same number of blocks. Apparently, when age and gender are closely matched between young hearing-impaired and normal-hearing adults, performance on vowel tasks may be explained by audibility alone.

The effects of auditory‐visual vowel and consonant training on speechreading performance

Recent work examined the effects of a novel approach to speechreading training using vowels, for normal‐hearing listeners tested in masking noise [C. Richie and D. Kewley‐Port, J. Acoust. Soc. Am. 114, 2337 (2003)]. That study showed significant improvements in sentence‐level speechreading for listeners trained on vowels compared to untrained listeners. The present study examined the effects of combining vowel and consonant training on speechreading abilities. Normal‐hearing adults were tested in auditory‐visual conditions in noise designed to simulate a hearing loss. Using a monosyllable context, one group of listeners received training on consonants, and another group received training on consonants and vowels combined. A control group did not receive training. All listeners performed speechreading pre‐ and post‐tests, on words and sentences. Comparison with the earlier study showed posttest sentence‐level speechreading increased by 10 percentage points for participants in the vowel training program, 8 ...

The effects of auditory and visual vowel training on speech reading performance

Speech reading, the use of visual cues to understand speech, may provide a substantial benefit for normal‐hearing listeners in noisy environments and for hearing‐impaired listeners in everyday communication. However, there exists great individual variability in speech reading ability, and studies have shown that only a modest improvement in speech reading ability is achieved with training. The purpose of this investigation was to determine the effects of a novel approach to speech reading training on word and sentence identification tasks. In contrast to previous research, which involved training on consonant recognition, this study focused on vowels. Two groups of normal‐hearing adults participated in auditory–visual (AV) conditions with added background noise. The first group of listeners received training on the recognition of 14 English vowels in isolated words, while the second group of listeners received no training. All listeners performed speech reading pre‐ and post‐tests, on words and sentences....

The effects of visual‐only vowel identification training on speech recognition for adults with hearing loss

Speechreading, the use of visual cues to speech, may provide benefit for listeners with hearing loss in everyday communication beyond that achieved with hearing aids alone. Recent work examined the effects of a novel approach to speechreading training, for normal‐hearing listeners tested in masking noise designed to simulate a hearing loss [C. Richie and D. Kewley‐Port, J. Acoust. Soc. Am. 117, 2570 (2005)]. That study showed improvements in sentence‐level speech recognition for listeners trained to speechread vowels under audiovisual conditions, compared to listeners trained to speechread consonants and untrained listeners. The present study examined the effects of vowel identification speechreading training on sentence‐level speech recognition, for adults with hearing loss. Computer‐based training and testing was administered visual‐only, in order to determine if training in the visual modality alone leads to gains in speech recognition. Results showed that vowel identification training under visual‐onl...

Speech recognition and listening effort across various conditions in adults with aphasia

Some of the common complaints among adults with aphasia are that it is difficult to understand speech in noise and that listening can be very effortful. Nonetheless, there has been limited research to date on speech recognition in noise or listening effort for adults with aphasia. Stanfield & Richie (2014) investigated speech recognition under various listening conditions for adults with non-fluent aphasia. Participants with aphasia performed better in quiet as compared to noise, as expected, and better in noise that consisted of multi-talker babble as compared to one competing talker. They also showed modest benefit from the addition of visual cues to speech over auditory-only speech recognition. However, subjective reports of listening effort were mixed and did not line up with performance on the various tests of speech recognition. In the present study, the relationship between speech recognition under various listening conditions and an objective measure of listening effort, response time, was examine...

The contribution of vowels to auditory-visual speech recognition and the contributions of Diane Kewley-Port to the field of speech communication

Throughout her career, Diane Kewley-Port has made enduring contributions to the field of Speech Communication in two ways—through her research on vowels and through her mentoring. Diane has contributed greatly to current knowledge about vowel acoustics, vowel discrimination and identification, and the role of vowels in speech recognition. Within that line of research, Richie & Kewley-Port (2008) investigated the effects of visual cues to vowels on speech recognition. Specifically, we demonstrated that an auditory-visual vowel-identification training program benefited sentence recognition under difficult listening conditions more than consonant-identification training and no training. In this presentation, I will describe my continuing research on the relationship between auditory-visual vowel-identification training and listening effort, for adults with normal hearing. In this study, listening effort was measured in terms of response time and participants were tested on auditory-visual sentence recognitio...

The effects of vowel identification training on sentence‐level speech recognition

Recent work examined the effects of a novel computer‐based approach to speech recognition training involving vowel identification [C. Richie, J. Acoust. Soc. Am. 121, 3045 (2007)]. When vowel identification training was done under auditory‐visual conditions with noise participants demonstrated modest improvements in sentence recognition, and when training was done under visual‐only conditions participants failed to show improvements in sentence recognition. However, sentence recognition was assessed for the CID Everyday Sentences in terms of words correctly recognized. Improvements in speech recognition may have occurred following training on a level lower than the word, and gone unrecognized given this scoring method. The purpose of the present study is to determine whether vowel identification training leads to improvements in speech recognition on a test of sentence recognition, as measured by correct identification of consonants and vowels. These findings have implications for sentence recognition tes...

Acoustical differences in mothers’ speech to children with cochlear implants versus normal‐hearing children

Infant‐directed speech includes higher pitch overall and more exaggerated pitch contours compared to adult‐directed speech. Clear speech is characterized by increased duration and expanded vowel space compared to conversational speech. This study investigated the differences between mothers’ speech to children with cochlear implants versus normal‐hearing children in terms of acoustic characteristics associated with infant‐directed speech and clear speech. Ten mothers of children with cochlear implants, 12‐ months postimplantation, and 25 mothers of normal‐hearing, 12‐month‐old children were recorded during a 5‐min play session between mother and child. Pitch range, vowel duration, and vowel space in mothers’ speech to children with cochlear implants and normal‐hearing children were examined. Results are discussed in terms of differences between groups depending upon the hearing status of the child, and in terms of the acoustic characteristics of infant‐directed speech and clear speech directed toward hear...

The effects of speechreading training on viseme categories for vowels

The status of visemes, groups of visually confusable speech sounds, for American English vowels has been disputed for some time. While some researchers claim that vowels are visually distinguishable, others claim that some vowels are visually confusable and comprise viseme categories. Data from our study on speechreading words and sentences were examined for evidence of vowel visemes [C. Richie and D. Kewley‐Port, J. Acoust. Soc. Am. 117, 2570 (2005)]. Normal‐hearing listeners were tested in auditory‐visual conditions in masking noise designed to simulate a hearing loss. They were trained on speechreading tasks emphasizing vowels, consonants, or vowels and consonants combined. Pre‐ and post‐training speechreading tests included identification of 10 vowels in CVC context. Pre‐training data (vowel‐identification confusion matrices) were used to determine whether vowel visemes exist for untrained speechreaders. Post‐training results were examined to determine whether the number of vowel response categories i...