Rajinder Koul

Identification and production of graphic symbols by individuals with aphasia: efficacy of a software application

The purpose of the current study was to evaluate the ability of individuals with severe or global aphasia to identify and produce graphic symbols using a software program that turns a microcomputer into an electronic communication device. During the first phase of the treatment program, subjects were trained to identify single symbols and two-symbol combinations from different grammatical categories. The second phase involved training on production of simple subject-verb and subject-verb-object constructions using symbols correctly identified by subjects in the first phase. A single-subject, multiple-baseline design across behaviors replicated across five subjects was used to assess the effects of treatment on symbol identification. Results indicated that all subjects identified noun symbols with a greater degree of accuracy than symbols representing verb referents. Performance on symbol production task varied across subjects. The most frequently observed errors on the symbol production task were omission...

Effects of Symbol, Referent, and Instructional Variables on the Acquisition of Aided and Unaided Symbols by Individuals with Autism Spectrum Disorders

Individuals with little or no functional speech as a result of autism spectrum disorders frequently rely on aided and unaided augmentative and alternative communication (AAC) symbols and signs to augment or replace natural speech. This has led investigators to identify the variables that are responsible for the acquisition and communicative use of graphic symbols and manual signs. The overall aim of this article is to evaluate the role of symbol, referent, and instructional variables on the acquisition of AAC symbols by individuals with autism and severe speech and language impairments.

Production of Graphic Symbol Sentences by Individuals with Aphasia: Efficacy of a Computer-Based Augmentative and Alternative Communication Intervention.

The study employed a single-subject multiple baseline design to examine the ability of 9 individuals with severe Brocas aphasia or global aphasia to produce graphic symbol sentences of varying syntactical complexity using a software program that turns a computer into a speech output communication device. The sentences ranged in complexity from simple two-word phrases to those with morphological inflections, transformations, and relative clauses. Overall, results indicated that individuals with aphasia are able to access, manipulate, and combine graphic symbols to produce phrases and sentences of varying degrees of syntactical complexity. The findings are discussed in terms of the clinical and public policy implications.

Synthetic Speech Perception in Individuals With and Without Disabilities

Individuals with little or no functional speech frequently rely on non-speech communication systems to augment or replace natural speech. These systems include speech generating devices (SGDs), which provide synthetic speech upon activation. This paper comprises a summary of research conducted over the past 20 years on the perception of synthetic speech by nondisabled listeners and listeners with intellectual, language, and hearing impairments. A wide variety of perceptual studies have been conducted into how human listeners understand synthetic speech. Research has shown that perceptions of synthetic speech in individuals with intellectual and/or language impairments depend upon several general factors, including the acoustic-phonetic properties of the synthesizer, complexity of the perceptual task, and the experience of the listener. Additionally, individuals with intellectual and/or language impairments exhibit greater difficulties than nondisabled listeners with regard to processing synthetic speech signals that impose substantial cognitive demands.

Speech Output Technologies in Interventions for Individuals with Autism Spectrum Disorders: A Scoping Review.

The purpose of this scoping review was to (a) map the research evidence on the effectiveness of augmentative and alternative communication (AAC) interventions using speech output technologies (e.g., speech-generating devices, mobile technologies with AAC-specific applications, talking word processors) for individuals with autism spectrum disorders, (b) identify gaps in the existing literature, and (c) posit directions for future research. Outcomes related to speech, language, and communication were considered. A total of 48 studies (47 single case experimental designs and 1 randomized control trial) involving 187 individuals were included. Results were reviewed in terms of three study groupings: (a) studies that evaluated the effectiveness of treatment packages involving speech output, (b) studies comparing one treatment package with speech output to other AAC modalities, and (c) studies comparing the presence with the absence of speech output. The state of the evidence base is discussed and several directions for future research are posited.

Comparison of Graphic Symbol Learning in Individuals with Aphasia and Right Hemisphere Brain Damage

This study compared the differences in performance on recognition of graphic symbols across time by individuals with aphasia, individuals with right-hemisphere brain damage, and neurologically normal adults. The subjects, seen individually, learned 40 Blissymbols. The symbols were selected so that the effects of symbol translucency and complexity on the recognition of graphic symbols could be examined. A paired-associate learning paradigm was used to teach the symbol-referent pairs to subjects. The results indicated that individuals with aphasia and neurologically normal adults do not differ significantly in recognition of graphic symbols. However, individuals with right-hemisphere damage recognized fewer symbols compared to individuals with aphasia and normal adults, suggesting that they have difficulty in associative learning of graphic symbols. Additionally, translucency was found to be a potent factor in the recognition of Blissymbols by all groups. The finding that individuals with severe chronic aphasia can learn and retain graphic symbols has significant clinical implications for aphasia rehabilitation.

Video modelling interventions to teach spontaneous requesting using AAC devices to individuals with autism: a preliminary investigation

This multiple baseline study investigated to what extent individuals with autism would learn to operate a speech generating device (SGD) to request a preferred object by observing a video model. The intervention consisted of each participant viewing a 10- to15-s video model that demonstrated the requesting of a preferred object using a SGD. Baseline, intervention and generalisation were all implemented within a public school, special education classroom. After viewing the video model, two participants displayed the ability to request preferred items using the SGD without prompting or cues. However, the participants did not generalise requesting using the SGD to a second preferred object. The study provides preliminary evidence that video modelling can be used to teach individuals with autism and severe cognitive disabilities requesting skills using an SGD.

Word identification and sentence verification of two synthetic speech systems by individuals with intellectual disabilities

This study compared the performance of a group of individuals with intellectual disabilities with a matched control group on word recognition and sentence verification tasks. Two text-to-speech systems (i.e., DECTalk™ and RealVoice™®) were used to present synthetic speech stimuli. A pretest was administered to exclude subjects who were unable to obtain perfect scores when experimental stimuli were presented via natural speech. Results revealed that DECTalk male and female synthetic voices were significantly (p < .01) superior to the RealVoice synthesizer across groups. Additionally, performance of individuals with intellectual disabilities was significantly (p < .05) poorer than that of nondisabled individuals on the sentence verification task. Data analyzed on practice effects indicated significant interaction (p < .05) between voice and task. The results of this study should be of interest to clinicians and researchers in recognizing the differences between individuals with cognitive disabilities and no...

Satisfaction with health care among people with hearing impairment: a survey of Medicare beneficiaries

Abstract Purpose: The purpose of this study was to investigate the determinants of access to and satisfaction with health care from Medicare participants with hearing impairment. Method: Raw data for the study was obtained from the 2004 Medicare Current Beneficiary Survey (MCBS). Satisfaction with care was assessed using 10 of the MCBS questions probing satisfaction in a number of areas related to health care. The data were analyzed using logistic regression. This analysis was conducted in three steps. The first step involved identifying potentially important predisposing and enabling variables that influenced satisfaction with care using univariate analysis. The second step involved fitting the variables retained from the first step into a multiple logistic regression equation to determine a preliminary main effects model. The final analysis included determining the odds ratio for each independent variable retained from the earlier analysis. Results: Individuals with hearing impairment demonstrated some level of dissatisfaction with quality of health care. Each of the MCBS satisfaction questions were significantly (p < 0.05) associated with at least one of the communication variables. Conclusions: Understanding the effects of hearing impairment on satisfaction with health care is critical to the delivery of effective and efficient services to individuals with such disabilities. Implications for Rehabilitation Presence of communication impairment, specifically hearing impairment, affects satisfaction with health care. Medical school training regarding methods to improve diagnosis and treatment of patients with communicative impairments could lead to improved patient–provider interactions and ultimately increased satisfaction with the provider and care given. Health care providers need to allow for extended appointments for patients with communication impairments. Time accommodations could prevent misunderstandings about diagnosis and treatment methods which otherwise might have detrimental results.

Effects of repeated listening experiences on the perception of synthetic speech by individuals with mild-to-moderate intellectual disabilities.

The purpose of this study was to examine whether individuals with intellectual disabilities (n = 18) demonstrate improvement in the perception of synthetic speech as a result of repeated exposure to it. Specifically, effects of training on novel versus repeated stimuli produced by the ETI Eloquence™ speech synthesizer were analyzed. Results revealed that training and experimental task each played a significant (p values < 0.01) role in the perception of synthetic words and sentences. Further, there was an absence of significant effect (p > 0.01) for stimulus type (i.e., repeated versus novel) suggesting that individuals with intellectual disabilities are able to generalize their knowledge of the acoustic-phonetic properties of synthetic speech to novel stimuli. Data are also presented for typical participants to establish a benchmark condition for the newly developed Eloquence synthesizer.