Enhanced speechreading in deaf adults: can short-term training/practice close the gap for hearing adults?

This study investigated effects of short-term training/practice on group and individual differences in deaf and hearing speechreaders. In two experiments, participants speechread sentences with feedback during training and without feedback during testing, alternating 10 times over six sessions spanning up to 5 weeks. Testing used sentence sets balanced for expected mean performance. In each experiment, participants were adults who reported good speechreading and either normal hearing (n = 8) or severe to profound hearing impairments (n = 8). The experiments were replicates, except that in one participants received vibrotactile speech stimuli in addition to visible speech during training, testing whether vibrotactile speech enhances speechreading learning. Results showed that (a) training/practice did not alter the relative performance among individuals or groups; (b) significant learning occurred when training and testing were conducted with speechreading only (although the magnitude of the effect was small); and (c) there was evidence that the vibrotactile training depressed rather than raised speechreading scores over the training period.     

The rehabilitation of adults with acquired hearing loss

The problems of adults with acquired hearing loss, together with aspects in the development of the rehabilitative skills of speechreading and auditory training are considered. An investigation carried out over a period of two years demonstrated how these skills may be acquired using single sensory and bisensory modes of instruction. The combined modes of speechreading and auditory training was found to produce the most effective communication. It was concluded that the combination of visual and auditory channels reduced sensory confusions.     

Attitude changes following speechreading training

Twelve hearing impaired adults were enrolled in intensive speechreading training classes following formal audiologic evaluation. They were given a video taped test of speechreading skill before and after twelve weeks (18 hours) of training. They were also given a post-treatment experimental questionnaire which asked for their opinions in the general areas of class procedures, communicative ability, feelings about the group and other related topics. The responses on the questionnaire were examined with regard to each individual's opinion, the total group feelings and the results of the speechreading test. It was found that although the speechreading test scores showed no significant pre- and post-treatment differences, the responses on the experimental questionnaire were generally positive. It was felt that this questionnaire may well be a useful tool as part of the evaluation of one's total communicative ability. Moreover, it was felt that the group experiences provided significant insights into hearing impairment and hearing handicap. The participants took on a more assertive approach to their communication difficulty. They tended to accept their handicap, had a greater understanding of the limitations and were able to offer suggestions to others so that they could understand more in various person-to-person social-communication situations.     

Speechreading performance under different conditions of video image, repetition, and speech rate.

Speechreading was assessed under different conditions of video image, repetition, and speech rate in three experiments on children who are deaf. The objective of the experiments was to obtain information for the design of interactive speechreading training programs using an interactive laser videodisc. Results of Experiment 1 showed that three different video images of testers (Entire-Face, 2/3 Profile, and Lips-Only), did not result in significantly different scores. Experiment 2 assessed which form of repetition (Entire-Face, 2/3 Profile, Lips-Only,) after the first Entire-Face presentation had the biggest effect on improving speechreading performance. The three different forms of repetition appeared to lead to a similar significant improvement. In Experiment 3, various speechreading stimuli were presented at four different speech rates. It appeared that these four speech rates did not significantly influence the speechreading scores. Results suggest that there is a wide range within which speaker-sender variables may vary without affecting the overall speechreading results.     

The relevance of body motion cues to both functional and dysfunctional communicative behavior.

This study assessed the extent ot which a speaker's visible, spontaneous body movements can contribute to the speech process. An experiment was conducted where subjects responded to videotaped verbal stimuli in one of three conditions (audiovisual, audiovisual without lip and facial cues, and audio alone) over four signal-to-noise ratios. The results indicated that: (1) visual cues can at times significantly improve comprehension scores, even with lip-facial cues not present; (2) visual cues significantly retard decay of comprehension as noise is increasingly introduced; (3) visual cues assist the comprehension of certain types of verbal segments, regardless of the information content expressed in those types of segments. A model of the bimodal aspect of the speech process is developed which illustrates both the cognitive and message-content dimensions. Possible future applications and research objectives are discussed in terms of normal and dysfunctional communicative behavior.     

Age-related changes in the visual perception of phonologically significant contrasts

The purpose of the present study was to determine whether the ability to speechread phonological contrasts is influenced by age. Forty-eight subjects were equally represented in three age groups: 8-9 years, 11-12 years and adults (20-29 years). The Hebrew version of the Speech Pattern Contrast (HeSPAC) test was administered by speechreading alone. Results showed that: age influenced performance; performance was contrast-dependent (place contrasts highly visible, manner and vowel height partially visible and voicing contrast invisible); hierarchy of contrast performance was similar for all age groups; Hebrew and English differ in the visual accessibility to speech contrasts in final voicing only; and females were found to be poorer speechreaders than males for the partially visible contrasts. The results suggest that speechreading at the phonological level follows a developmental course. The implications of these findings extend to recommendations provided to children in noisy listening conditions, speechreading training in hearing-impaired children and those with central auditory processing disorders (CAPD), and to the design of sensory aids.     

Difficulties experienced by hearing-aid candidates and hearing-aid users

Responses to an open-ended questionnaire were obtained from 250 hearing-aid candidates who had never worn a hearing aid and from 250 experienced hearing-aid users. The questionnaire stated 'Please make a list of the difficulties which you have as a result of your hearing loss.' The responses were divided into six major categories. The hearing-aid candidates reported more problems than the experienced users in the categories of (a) understanding speech where speechreading would normally be used (92% versus 81%), and (b) understanding speech where speechreading would normally not be used (51% versus 43%). A similar number of respondents in both groups reported problems in the categories of (c) personal difficulties (11%), (d) audiological or medical difficulties (18%), and (e) difficulties associated with environmental sounds (34%). Thirty-five per cent of the hearing-aid users reported (f) difficulties associated with their hearing aids. The most frequently reported specific difficulty in both groups was watching television (47% of the candidates and 37% of the users). Twenty-one per cent in each group reported difficulty conversing on the telephone.     

Computer applications in audiology and rehabilitation of the hearing impaired

Computers are playing an ever-increasing role in audiology. The potential applications of computers in audiology, speech pathology, and aural rehabilitation are described. These include the use of computers in adaptive testing, speech analysis and synthesis, automatic extraction of speech features, supplemental speechreading aids, analysis and synthesis of speechreading cues, language analysis, and computer simulation of the effect of specific speech training strategies.     

Preparing for communication interactions: the value of anticipatory strategies for adults with hearing impairment.

Some people with hearing impairment may use anticipatory strategies to prepare for an upcoming communication interaction, such as a doctor's appointment. They may consider vocabulary and statements that might occur, and they may practice speechreading a partner saying the items. Experiment 1 evaluated the effectiveness of two types of anticipatory strategies: workbook activities and situation-specific lipreading practice. Two groups of normal-hearing subjects were asked to prepare for a communication interaction in a bank setting where they would be required to recognize speech using only the visual signal. Each group was assigned to one type of anticipatory strategy. A third group served as a control group. Experiment 2 evaluated whether multifaceted anticipatory practice improved cochlear implant users' ability to recognize statements and words audiovisually that might occur in a doctor's office, bank, movie theater, and gas station. One group of implanted subjects received 4 days of training, 1 day for each setting, and a second group served as a control group. In both experiments, subjects who used anticipatory strategies did not improve their performance on situation-specific sentence tests more than the control subjects.     

The design of CAST (Computer-Aided Speechreading Training)

The underlying theoretical assumptions, goals, design, and implementation of a Computer-Aided Speechreading Training system (CAST) are described as a case study in program design. This computerized speechreading assessment and training system simulates face-to-face intervention and is designed to be one component of a comprehensive aural rehabilitation program for preretirement adults with acquired mild-to-moderate hearing loss. The interactive, automated course consists of eight training lessons, each focusing on a particular viseme that is practiced by a modified discourse tracking method using viseme-specific texts. Three basic speechreading skills are emphasized: visual speech perception, use of linguistic redundancy, and use of feedback between message sender and receiver. These skills are evaluated separately by means of CAST tracking rate, receiver strategy, and inferred error type. Four example case assessments are provided to illustrate the potential applications of CAST as a standardizable rehabilitative tool. An independent program evaluation is provided in a companion paper (Gagné, Dinon, & Parsons, 1991). Comparisons between CAST, face-to-face tracking procedures, and natural discourse are presented and discussed with reference to theoretical and clinical issues in speechreading and program evaluation.     

Enhanced visual speech perception in individuals with early-onset hearing impairment.

PURPOSE: L. E. Bernstein, M. E. Demorest, and P. E. Tucker (2000) demonstrated enhanced speechreading accuracy in participants with early-onset hearing loss compared with hearing participants. Here, the authors test the generalization of Bernstein et al.'s (2000) result by testing 2 new large samples of participants. The authors also investigated correlates of speechreading ability within the early-onset hearing loss group and gender differences in speechreading ability within both participant groups. METHOD: One hundred twelve individuals with early-onset hearing loss and 220 individuals with normal hearing identified 30 prerecorded sentences presented 1 at a time from visible speech information alone. RESULTS: The speechreading accuracy of the participants with early-onset hearing loss (M=43.55% words correct; SD=17.48) significantly exceeded that of the participants with normal hearing (M=18.57% words correct; SD=13.18), t(330)=14.576, p<.01. Within the early-onset hearing loss participants, speechreading ability was correlated with several subjective measures of spoken communication. Effects of gender were not reliably observed. CONCLUSION: The present results are consistent with the results of Bernstein et al. (2000). The need to rely on visual speech throughout life, and particularly for the acquisition of spoken language by individuals with early-onset hearing loss, can lead to enhanced speechreading ability.     

Interactive Microcomputer Method of Lipreading (MIMILLE): an interactive microcomputerized method of lipreading

A computer-aided speechreading assessment and training system is presented. It is intended to be one component of a comprehensive aural rehabilitation program for preretirement adults with acquired mild-to-moderate hearing loss. Each lesson focuses on a different viseme which is practiced using the 'discourse tracking' method. The system allows the evaluation of the basic skills necessary for lipreading, i.e. good visual speech decoding and effective use of lingustic redundancy and transmitter feedback, by evaluating separately tracking rate, strategy, and types of errors.     

Audiovisual speech perception in elderly cochlear implant recipients

OBJECTIVES/HYPOTHESIS: This study examined the speech perception skills of a younger and older group of cochlear implant recipients to determine the benefit that auditory and visual information provides for speech understanding. STUDY DESIGN: Retrospective review. METHODS: Pre- and postimplantation speech perception scores from the Consonant-Nucleus-Consonant (CNC), the Hearing In Noise sentence Test (HINT), and the City University of New York (CUNY) tests were analyzed for 34 postlingually deafened adult cochlear implant recipients. Half were elderly (i.e., >65 y old) and other half were middle aged (i.e., 39-53 y old). The CNC and HINT tests were administered using auditory-only presentation; the CUNY test was administered using auditory-only, vision-only, and audiovisual presentation conditions RESULTS: No differences were observed between the two age groups on the CNC and HINT tests. For a subset of individuals tested with the CUNY sentences, we found that the preimplantation speechreading scores of the younger group correlated negatively with auditory-only postimplant performance. Additionally, older individuals demonstrated a greater reliance on the integration of auditory and visual information to understand sentences than did the younger group CONCLUSIONS: On average, the auditory-only speech perception performance of older cochlear implant recipients was similar to the performance of younger adults. However, variability in speech perception abilities was observed within and between both age groups. Differences in speechreading skills between the younger and older individuals suggest that visual speech information is processed in a different manner for elderly individuals than it is for younger adult cochlear implant recipients.     

Communication skills and thalamic lesion: Strategies of rehabilitation

Aim

To describe the speech rehabilitation history of patients with thalamic lesions.

Background

Thalamic lesions can affect speech and language according to diverse thalamic nuclei involved. Because of the strategic functional position of the thalamus within the cognitive networks, its lesion can also interfere with other cognitive processes, such as attention, memory and executive functions. Alterations of these cognitive domains contribute significantly to language deficits, leading to communicative inefficacy. This fact must be considered in the rehabilitation efforts.

Materials and methods

Whereas evaluation of cognitive functions and communicative efficiency is different from that of aphasic disorder, treatment should also be different. The treatment must be focused on specific cognitive deficits with belief in the regaining of communicative ability, as well as it occurs in therapy of pragmatic disorder in traumatic brain injury: attention process training, mnemotechnics and prospective memory training.

Results

According to our experience: (a) there is a close correlation between cognitive processes and communication skills; (b) alterations of attention, memory and executive functions cause a loss of efficiency in the language use; and (c) appropriate cognitive treatment improves pragmatic competence and therefore the linguistic disorder.

Conclusion

For planning a speech-therapy it is important to consider the relationship between cognitive functions and communication. The cognitive/behavioral treatment confirms its therapeutic efficiency for thalamic lesions.     

Visual evoked-response components related to speechreading and spatial skills in hearing and hearing-impaired adults

Averaged visual evoked responses (VER) to light flashes which varied systematically in brightness and predictability were collected from 24 hearing and 24 hearing-impaired adults. In addition, speechreading, abstract reasoning, and spatial relations tests were administered. Separate principal components analyses of the VERs were conducted on each group to replicate and extend our previous report of an early VER component (VF16) which reflected individual differences in the speechreading skills of hearing subjects. VF16 appeared in both analyses, confirming its replicability as a latent VER component. VF16 correlated with speechreading skill in hearing-impaired males (r = -.73), under stimulus conditions identical to those in our previous study. However, its correlations with speechreading skills in hearing subjects were not significant. VF16 also varied systematically with stimulus predictability and correlated with spatial ability in both groups only when the time of occurrence of the light flashes was predictable. These data tentatively suggest that VF16 is a VER correlate of individual differences in a psychologically dynamic process, perhaps involving expectancy, which may relate to the performance of hearing-impaired and hearing people in visually based communication or cognitive processing situations.     

Perception of speech pattern contrasts from auditory presentation of voice fundamental frequency

The perception of phonologically significant speech pattern contrasts was measured in normally hearing subjects who were presented with F0 contours alone, speechreading alone, and the two in combination. For the suprasegmentals and final consonant voicing, perception in the combined condition was dominated by F0. For the vowel, consonant place, and final consonant continuance contrasts, perception in the combined condition was dominated by vision. For initial consonant voicing and continuance, however, there was clear evidence of interaction between F0 and speechreading. Here, the combined score was higher than either of the single-modality scores, and also higher than could be predicted on the assumption that the auditory and visual channels act as statistically independent channels of information.     

How to assess outcome of hearing aid fitting in children.

Assessment of outcome of hearing aid fitting in children should contain several dimensions: audibility, speech recognition, subjective benefit and speech production. Audibility may be determined by means of aided hearing thresholds or real-ear measurements. For determining speech recognition, methods different from those used for adult patients must be used, especially for children with congenital hearing loss. In these children the development of the spoken language and vocabulary has to be considered, especially when testing speech recognition but also with regard to speech production. Subjective assessment of benefit to a large extent has to rely on the assessment by parents and teachers for children younger than school age. However, several studies have shown that children from the age of around 7 years can usually produce reliable responses in this respect. Speech production has to be assessed in terms of intelligibility by others, who may or may not be used to the individual child's speech. Ideally, the outcome should be assessed repeatedly at suitable intervals in order to be able to follow the child's communicative development.     

The relationship between verbal ability and sentence-based speechreading.

Eighteen hearing-impaired subjects participated in the present study. The purpose was to investigate one general question: The nature of the relationship between verbal ability and speechreading. Verbal ability was assessed by two types of measure: a test of vocabulary size, and four tests of lexical access speed. The results demonstrated that lexical access speed was related to speechreading performance. Vocabulary size was not found to be directly related to the speechreading criterion; rather, its influence was in an indirect fashion via its relation to lexical access speed. It was concluded that lexical access speed could be used as a diagnostic tool, such that when an individual demonstrates lexical access that is unreasonably slow, it could be taken as an indication to suggest that rehabilitation programs should emphasize alternatives to speechreading. A general implication of the present results is that absence of relation between a predictor variable and the speechreading criterion does not necessarily imply absence of relation between the two. There is still a possibility that the predictor variable might be indirectly related to the speechreading criterion.     

Acoustic and electrical pattern analysis of consonant perceptual cues used by cochlear implant users

It is hypothesized that for postlingually deafened adult cochlear implant (CI) users, a significant source of their perceptual performance variability is attributable to differences in their ability to discriminate the basic perceptual cues that are important in speech recognition. Previous research on 'electric hearing' has identified consistent perceptual cues for vowel recognition. However, the results on consonant perception by CI users are less clear. The primary purpose of this study is to present a quantitative method of evaluating potential 'electric cues' used by CI users in consonant identification. Since the actual input signals to the auditory periphery of CI users are electric in nature, we elected to measure the CI electric discharge patterns in addition to the original acoustic waveforms. The characteristics of the electric discharge patterns in response to intervocalic consonants were quantified and correlated with the dimensions of CI patients' perceptual spaces, which were computed from multidimensional scaling analyses of their consonant confusion matrices. The results agree with most, but not all, commonly accepted acoustic cues used by normal-hearing listeners. The correlation findings also suggest that CI users employ different sets of 'electric cues' in perceiving consonants that differ in their manner of articulation. Specifically, spectral and temporal cues associated with slowly changing formant structures and transitions, and features associated with frication and high-frequency noise, are all highly correlated with the perceptual dimensions of all CI users. However, rapidly changing formant transitions, such as those present in stop consonants, did not appear to play a significant role in consonant recognition by more poorly performing CI subjects. The perceptual results were consistent with our physical findings that the SPEAK coding strategy partially degraded the rapidly changing formant transitions.     

Perceptual Restoration of Degraded Speech Is Preserved with Advancing Age

Cognitive skills, such as processing speed, memory functioning, and the ability to divide attention, are known to diminish with aging. The present study shows that, despite these changes, older adults can successfully compensate for degradations in speech perception. Critically, the older participants of this study were not pre-selected for high performance on cognitive tasks, but only screened for normal hearing. We measured the compensation for speech degradation using phonemic restoration, where intelligibility of degraded speech is enhanced using top-down repair mechanisms. Linguistic knowledge, Gestalt principles of perception, and expectations based on situational and linguistic context are used to effectively fill in the inaudible masked speech portions. A positive compensation effect was previously observed only with young normal hearing people, but not with older hearing-impaired populations, leaving the question whether the lack of compensation was due to aging or due to age-related hearing problems. Older participants in the present study showed poorer intelligibility of degraded speech than the younger group, as expected from previous reports of aging effects. However, in conditions that induce top-down restoration, a robust compensation was observed. Speech perception by the older group was enhanced, and the enhancement effect was similar to that observed with the younger group. This effect was even stronger with slowed-down speech, which gives more time for cognitive processing. Based on previous research, the likely explanations for these observations are that older adults can overcome age-related cognitive deterioration by relying on linguistic skills and vocabulary that they have accumulated over their lifetime. Alternatively, or simultaneously, they may use different cerebral activation patterns or exert more mental effort. This positive finding on top-down restoration skills by the older individuals suggests that new cognitive training methods can teach older adults to effectively use compensatory mechanisms to cope with the complex listening environments of everyday life.