Multi-modal access method (eye-tracking + switch-scanning) for individuals with severe motor impairment: A preliminary investigation.

Individuals with severe motor impairments often require alternative means to access computers and communication technology. A range of alternative access devices exist; however, most rely on use of a single access modality. While this approach works for some individuals, it can be limiting for others. This study explored the use of a multi-modal prototype (eye-tracking + switch-scanning) on typing performance with a range of individuals with motor impairments. The multi-modal prototype was compared to eye-tracking alone for this study. Results indicated that the multi-modal prototype had significantly slower typing rate but significantly lower total errors compared to eye-tracking alone. Analysis of individual data revealed four subgroups of clinical relevance including individuals that 1) benefit from multi-modal, 2) benefit from eye-tracking, 3) demonstrate learning and 4) demonstrate fluctuating performance.

A protocol for identification of early bulbar signs in amyotrophic lateral sclerosis.

The purpose of this project is to identify characteristics that may be of assistance in establishing the diagnosis and monitoring early progression of bulbar dysfunction in patients with Amyotrophic Lateral Sclerosis (ALS). Early identification of bulbar dysfunction would assist in clinical trials and management decisions. A database of 218 clinic visits of patients with ALS was developed and formed the basis for these analyses. As a framework for the description of our methodology, the Disablement Model [World Health Organization. WHO International classification of impairment, activity, and participation: beginner's guide. In: WHO, editor. Beta-1 draft for field trials; 1999] was utilized. Our data identified that the strongest early predictors of bulbar speech dysfunction include altered voice quality (laryngeal control), speaking rate, and communication effectiveness. A protocol for measuring these speech parameters was therefore undertaken. This paper presents the protocol used to measure these bulbar parameters.

Effects of linguistic cues and stimulus cohesion on intelligibility of severely dysarthric speech.

This study examined the effects of supplemental cues on the intelligibility of unrelated sentences and related sentences (narratives) produced by 4 women with severe dysarthria secondary to cerebral palsy. Visual images containing alphabet, topic, combined (alphabet and topic together), and no cues were imposed in real time on audio speech samples and presented to 72 nondisabled listeners. Statistical results showed that cue conditions had similar effects on unrelated and on related sentence intelligibility. Combined cues resulted in higher intelligibility scores than any other cue condition, no cues resulted in lower intelligibility scores than any other cue condition, and alphabet cues yielded higher intelligibility scores than topic cues. Intelligibility of related and unrelated sentences differed only for alphabet cues where related sentences had greater intelligibility than unrelated sentences. Results are discussed relative to the quantity and type of cues.

A treatment for vocal cord dysfunction in female athletes: an outcome study.

OBJECTIVES: This article reports the outcome of a speech pathology treatment program for vocal cord dysfunction (VCD) in 20 adolescent female athletes. STUDY DESIGN: A retrospective, nonrandomized group design was used to collect the outcome data. METHODS: Twenty consecutive referrals of female athletes diagnosed as having symptoms of VCD during exercise were assessed, treated, and followed for at least 6 months after treatment. RESULTS: Ninety-five percent of the participants reported the ability to control symptoms of VCD during exercise up to 6 months after treatment. Asthma medications were no longer used by 80% of the athletes. All of the females continued to participate in athletics. CONCLUSION: Speech pathology intervention focusing on respiratory control of VCD in adolescent female athletes is an effective treatment resulting in the athletes' ability to control the symptoms of VCD in exercise for at least 6 months after treatment.

Functional outcome assessment in dysarthria.

Strategies for the functional assessment of communication disorders experienced by persons with dysarthria can be based on the Chronic Disabilities Model described by Nagi (1991), which considers a disorders at five different levels, ranging from pathophysiology at the level of the tissue to the societal levels of dysfunction. Outcomes can be measured at all levels of the model. For example, at the pathophysiologic level, outcomes may indicate events at the tissue level during the course of the disease, whereas, at the level of the disability, outcomes reveal the adequacy of speech production using compensatory strategies in communicative contexts, and at the societal level, they may indicate the overall degree of success a speaker has in specific real-world speaking situations. This article focuses on "functional" assessment of persons with dysarthria. Thus, assessment is viewed from the perspective of how speech and the use of speech can be measured in functional situations over time or as a result of treatment.

DECTalk and MacinTalk speech synthesizers: intelligibility differences for three listener groups.

This study examined word level intelligibility differences between DECTalk and MacinTalk speech synthesizers using the Modified Rhyme Test in an open format transcription task. Three groups of listeners participated: inexperienced, speech-language pathologists, and speech synthesis experts. Results for between-subjects ANOVA showed that the expert group correctly identified a significantly higher number of words than each of the other listener groups. For the within-subjects factor of voice, simple effects ANOVA and post hoc contrasts within each group showed that listeners had higher intelligibility scores for the DECTalk male voice, Perfect Paul, than for the MacinTalk male voice, Bruce. No other pairwise gender/age-matched differences were found between the two synthesizers.

Obturator prostheses after cancer surgery: an approach to speech outcome assessment.

PURPOSE: This article describes a speech assessment protocol for patients using either obturator prostheses or speech aid prostheses for surgically acquired defects due to cancer of the maxilla and/or soft palate. METHODS: This protocol is structured according to the executive summary of "Disability in America: Toward a National Agenda For Prevention" a report formulated by the Institute of Medicine that describes four levels of disorder: (1) pathology, (2) impairment, (3) functional limitation, and (4) disability. Assessment instruments included (1) the Sentence Intelligibility Test to measure the rate and understandability of speech, (2) a speech physiology system to measure appropriate separation of the nasal/nasopharyngeal and oral compartments, (3) a 13-point interval scale to rate speech nasality, and (4) a scale to rate self-perceptions of communication effectiveness. RESULTS: The results from two patients are reported to illustrate the outcome assessment protocol.

The effect of rate control on the intelligibility and naturalness of dysarthric speech.

Speaking rates of individuals with severe ataxic dysarthria (n = 4) and severe hypokinetic dysarthria (n = 4) were reduced to 60% and 80% of habitual rates using four different pacing strategies (Additive Metered, Additive Rhythmic, Cued Metered, and Cued Rhythmic). Effects of rate control on sentence and phoneme intelligibility and speech naturalness were examined. Sentence intelligibility improved for both groups, with metered pacing conditions associated with the largest improvement in scores. Similar improvements as speaking rates were reduced were not seen for the phoneme intelligibility task; however, one must recognize that sentence and phoneme intelligibility tasks are different. Slowing the rate of dysarthric speakers did not have as marked an impact on speech naturalness as it did for normal speakers whose naturalness decreased at slowed rates. Metered rate control strategies were associated with the lowest ratings of naturalness for all subject groups. A potential explanation for the discrepancies between the findings for sentence and phoneme intelligibility is offered.

Extended communication samples of augmented communicators. II: Analysis of multiword sequences.

The three primary purposes of this project are (a) to identify those word sequences that occur frequently across a group of 10 linguistically intact augmented communicators, (b) to determine the communality with which the various augmented communicators use specific word sequences, and (c) to evaluate the usefulness of word sequences in providing keystroke savings for users of augmentative and alternative communication (AAC) devices as compared to letter-by-letter spelling or single-word retrieval. Communication samples were collected for 14 consecutive days from 10 subjects who used AAC devices. These samples were analyzed with custom software to determine the frequency of occurrence of one-, two-, three-, four-, and five-word sequences. The results revealed that three-, four-, and five-word sequences occurred very infrequently within and across communication samples. Two-word sequences occurred much more frequently than the longer sequences. The authors concluded that clinicians should continue to encourage linguistically intact clients to select long messages (three words or more) for their AAC devices based on message content and the urgency with which messages need to be delivered rather than relying exclusively on statistical analysis. However, statistically based multiword analysis should not be abandoned. Frequently occurring one- and two-word sequences may be an important source of messages that will increase communication efficiency when stored and retrieved in an AAC device.

Perceived articulatory adequacy and velopharyngeal function in dysarthric speakers.

Twenty-four dysarthric speakers with etiologies of brain injury or stroke were placed into one of two groups based on aerodynamic measures of velopharyngeal status. Group I contained 13 individuals who were velopharyngeally incompetent in that nasal air flow was always noted during the stop phase of voiceless plosive sounds. Group II contained 11 individuals who at times achieved complete velopharyngeal closure. Certain measures of perceived articulatory adequacy were found to distinguish between the two groups. Specifically, speakers who were velopharyngeally incompetent produced an articulatory error pattern characterized by better performance for the consonant subcategory nasals-glides than for pressure consonants. Speakers who at times were achieving velopharyngeal closure did not exhibit a marked difference between these two consonant subcategories. Clinical use of measurement of articulatory adequacy as a gross indicator of velopharyngeal competence is suggested and limitations are discussed.

Synthetic and natural speech preferences of male and female listeners in four age groups.

The purpose of this investigation was to examine the preferences of listeners of both sexes in four age groups with regard to natural and computer-generated synthetic speech in six different contexts. The subjects (listeners) for this study included 5 males and 5 females in each of four age groups (6-8 year olds, 10-12 year olds, adolescents, and adults). The listeners rated their preferences for 11 different voices (four natural and seven synthetic) on a 5-point Likert scale. Their preferences were rated for six communication contexts dependent on the potential user of the voice (adult male, adult female, child male, child female, computer, and self). The data were analyzed separately for each of the six communication contexts. In general, female listeners across the age range indicated that only natural female voices (adult or child) were acceptable alternatives to their own speech, thus rejecting the natural male voices as well as the synthetic voices. Male listeners appeared to be somewhat more flexible in terms of gender-appropriateness for themselves and other adult men, but selected female-sounding voices for women and female children. Children preferred to have computers produce synthesized speech, while adults preferred computers with more natural-sounding voices. The results of this investigation raise a number of issues related to the combined effects of age and gender-appropriateness of natural and synthetic speech. These are discussed in terms of their implications for the future development of synthetic speech technology used in communication devices.

Articulatory adequacy in dysarthric speakers: a comparison of judging formats.

An articulatory inventory was administered to 19 dysarthric adults and scored using two judging formats--phoneme identification and traditional testing. Results indicated that samples judged using the traditional testing format, in which the judge knew the target phoneme, were consistently scored more accurately than those that had been judged using a phoneme identification format, in which the target was not known. Although overall both judging formats were characterized by high inter-rater reliability, the traditional testing format was less reliable than phoneme identification with samples obtained from severely involved speakers. Potential uses of articulatory inventories for dysarthric adults are described.

Speech-muscle visuomotor tracking in dysarthric and nonimpaired speakers.

Assessment of speech-muscle function during nonspeech tasks may provide an important component in the clinical evaluation of speech-motor disorders. Various methodological problems have limited the value of such data in the past. The goal of the present study was to evaluate a set of instrumental, objective procedures for assessment of the nonspeech performance capabilities of different speech-muscle systems. Subjects included 10 nonimpaired adults and a diverse group of 6 adult dysarthric individuals. Each subject performed visuomotor tracking of a 0.6-Hz sinusoidal target with the lower lip, jaw, larynx, and respiratory systems. Cross correlation and phase data were used to describe tracking performance. The nonimpaired subjects showed consistently high cross correlations with little phase shift. The dysarthric subjects showed a wide range of tracking performance which was generally consistent with their overall levels of speech performance and levels of neurological impairment. Differential levels of performance were noted across speech subsystems in some dysarthric subjects. In general, the results suggest that visuomotor-tracking paradigms provide a viable approach to clinical evaluation of speech-muscle function in nonspeech tasks.

Modification of breath patterning to increase naturalness of a mildly dysarthric speaker.

The case of a 20-year-old, closed head injured male with mild dysarthria is presented. The decreased naturalness of speech was related to short, uniform breath groups, inhalation during every pause, and restricted fundamental frequency. Data related to patterns of breathing and pausing during samples of connected speech along with measures of respiratory control are presented in order to illustrate techniques for assessing and training speech naturalness.

Expressive communication disorders in persons with multiple sclerosis: a survey.

The purpose of this study was to survey individuals with multiple sclerosis to determine (1) the presence and severity of their expressive communication disorders, (2) the extent expressive communication problems interfere with employment, and (3) the frequency of using communication augmentation equipment. An eight-page questionnaire was distributed to 656 persons diagnosed as having multiple sclerosis, who returned completed questionnaires. Twenty-three percent of the total sample reported the presence of "speech or other communication problems." Four percent of the total sample indicated that strangers were unable to understand them. Of this group 28.8% reported that they used communication augmentation equipment.

Communication augmentation systems: quantification in natural settings.

Although observation in clinical settings of communication augmentation system use by severely physically handicapped nonspeaking persons is important, monitoring of such use in natural settings can yield valuable information about the system, communication frequency, and unique communication needs of the individual. This study was designed to evaluate the use of communication partners as data recorders. For nonspeaking, severely physically handicapped subjects were observed in the home, school or treatment settings by a trained observer and a minimally trained communication partner. Issues of partner training and length of time required to obtain a representative sample of communication arose as a result of this study. More work in the areas of automated data collection systems or use of communication partners as data collectors is required before claiming that accurate communication interactions can be recorded in natural settings.

Frequency of word occurrence in communication samples produced by adult communication aid users.

Communication samples generated by five nonspeaking adults using Canon Communicators were collected for 14 consecutive days. Samples were analyzed to determine frequency of word occurrence. A core vocabulary of the 500 most frequently occurring words was analyzed further to determine spelling level and proportion of complete communication samples represented by subsets of the core vocabulary list. The 500 core vocabulary words represented 80% of the total words in the combined communication samples for the 5 subjects. Of all messages generated by the subjects, 33% could be communicated in their entirety using words from the core vocabulary list. The communication of the remaining messages required one or more words in addition to the core vocabulary. The spelling grade level of the words in the core vocabulary list did not exceed the seventh grade. The implications of the results for designing and customizing communication aids and for potential user training are discussed.

Microcomputer-based communication augmentation systems for two nonspeaking, physically handicapped persons with severe visual impairment.

Two different microcomputer-based communication systems were developed for nonspeaking physically handicapped individuals with severe visual impairment. One subject was 24 years old and had an inoperative optic glioma which impaired motor function as well as vision. The second subject was cortically blind with severe motor limitation secondary to an automobile accident which occurred at 17 years of age. Both communication systems employed speech synthesis as a control feature to compensate for visual impairment. Both subjects have learned to use their communication systems. The second subject has not achieved extended, independent system use due to reduced vigilance and attention span.