Translating Principles of Neural Plasticity Into Research on Speech Motor Control Recovery and Rehabilitation

from the Journal of Speech, Language, and Hearing Research

Purpose: To review the principles of neural plasticity and make recommendations for research on the neural bases for rehabilitation of neurogenic speech disorders.

Method: A working group in speech motor control and disorders developed this report, which examines the potential relevance of basic research on the brain mechanisms involved in neural plasticity and discusses possible similarities and differences for application to speech motor control disorders. The possible involvement of neural plasticity in changes in speech production in normalcy, development, aging, and neurological diseases and disorders was considered. This report focuses on the appropriate use of functional and structural neuroimaging and the design of feasibility studies aimed at understanding how brain mechanisms are altered by environmental manipulations such as training and stimulation and how these changes might enhance the future development of rehabilitative methods for persons with speech motor control disorders.

Conclusions: Increased collaboration with neuroscientists working in clinical research centers addressing human communication disorders might foster research in this area. It is hoped that this article will encourage future research on speech motor control disorders to address the principles of neural plasticity and their application for rehabilitation.

The Efficacy of Fast ForWord Language Intervention in School-Age Children With Language Impairment: A Randomized Controlled Trial

from the Journal of Speech, Language, and Hearing Research

Purpose: A randomized controlled trial was conducted to compare the language and auditory processing outcomes of children assigned to receive the Fast ForWord Language intervention (FFW-L) with the outcomes of children assigned to nonspecific or specific language intervention comparison treatments that did not contain modified speech.

Method: Two hundred sixteen children between the ages of 6 and 9 years with language impairments were randomly assigned to 1 of 4 conditions: (a) Fast ForWord Language (FFW-L), (b) academic enrichment (AE), (c) computer-assisted language intervention (CALI), or (d) individualized language intervention (ILI) provided by a speech-language pathologist. All children received 1 hr and 40 min of treatment, 5 days per week, for 6 weeks. Language and auditory processing measures were administered to the children by blinded examiners before treatment, immediately after treatment, 3 months after treatment, and 6 months after treatment.

Results: The children in all 4 conditions improved significantly on a global language test and a test of backward masking. Children with poor backward masking scores who were randomized to the FFW-L condition did not present greater improvement on the language measures than children with poor backward masking scores who were randomized to the other 3 conditions. Effect sizes, analyses of standard error of measurement, and normalization percentages supported the clinical significance of the improvements on the Comprehensive Assessment of Spoken Language (E. Carrow-Woolfolk, 1999). There was a treatment effect for the Blending Words subtest of the Comprehensive Test of Phonological Processing (R. K. Wagner, J. K. Torgesen, & C. A. Rashotte, 1999). Participants in the FFW-L and CALI conditions earned higher phonological awareness scores than children in the ILI and AE conditions at the 6-month follow-up testing.

Conclusion: Fast ForWord Language, the intervention that provided modified speech to address a hypothesized underlying auditory processing deficit, was not more effective at improving general language skills or temporal processing skills than a nonspecific comparison treatment (AE) or specific language intervention comparison treatments (CALI and ILI) that did not contain modified speech stimuli. These findings call into question the temporal processing hypothesis of language impairment and the hypothesized benefits of using acoustically modified speech to improve language skills. The finding that children in the 3 treatment conditions and the active comparison condition made clinically relevant gains on measures of language and temporal auditory processing informs our understanding of the variety of intervention activities that can facilitate development.

The Influence of Linguistic Content on the Lombard Effect

from the Journal of Speech, Language, and Hearing Research

Purpose: The Lombard effect describes the tendency for speakers to increase pitch, intensity, and duration in the presence of noise. It is unclear whether these modifications are uniformly applied across all words within an utterance or whether information-bearing content words are further enhanced compared with function words. In the present study, the authors investigated the influence of linguistic content on acoustic modifications made to speech in noise.

Method: Sixteen speaker–listener pairs engaged in an interactive cooperative game in quiet, 60 dB of multitalker noise, and 90 dB of multitalker noise. Speaker productions were analyzed to examine differences in fundamental frequency (F0), intensity, and duration of target words in sentences across noise conditions.

Results: Proportional increases in F0, intensity, and duration were noted for all word types as noise increased from quiet to 60 dB. From quiet to 90 dB, content words that referred to agents, objects, and locations were disproportionately elongated compared with function words. Additionally, agents were further enhanced by increased F0.

Conclusions: At moderate noise levels, most word types appear to be uniformly boosted in F0, intensity, and duration. As noise increases, linguistic content shapes the extent of the Lombard effect, with F0 and duration serving as primary cues for marking information-bearing word types.

Translating Principles of Neural Plasticity Into Research on Speech Motor Control Recovery and Rehabilitation

from the Journal of Speech, Language, and Hearing Research

Purpose: To review the principles of neural plasticity and make recommendations for research on the neural bases for rehabilitation of neurogenic speech disorders.

Method: A working group in speech motor control and disorders developed this report, which examines the potential relevance of basic research on the brain mechanisms involved in neural plasticity and discusses possible similarities and differences for application to speech motor control disorders. The possible involvement of neural plasticity in changes in speech production in normalcy, development, aging, and neurological diseases and disorders was considered. This report focuses on the appropriate use of functional and structural neuroimaging and the design of feasibility studies aimed at understanding how brain mechanisms are altered by environmental manipulations such as training and stimulation and how these changes might enhance the future development of rehabilitative methods for persons with speech motor control disorders.

Conclusions: Increased collaboration with neuroscientists working in clinical research centers addressing human communication disorders might foster research in this area. It is hoped that this article will encourage future research on speech motor control disorders to address the principles of neural plasticity and their application for rehabilitation.

Auditory Processing Disorders: An Update for Speech-Language Pathologists

from the American Journal of Speech-Language Pathology

Purpose: Unanswered questions regarding the nature of auditory processing disorders (APDs), how best to identify at-risk students, how best to diagnose and differentiate APDs from other disorders, and concerns about the lack of valid treatments have resulted in ongoing confusion and skepticism about the diagnostic validity of this label. This poses challenges for speech-language pathologists (SLPs) who are working with school-age children and whose scope of practice includes APD screening and intervention. The purpose of this article is to address some of the questions commonly asked by SLPs regarding APDs in school-age children. This article is also intended to serve as a resource for SLPs to be used in deciding what role they will or will not play with respect to APDs in school-age children.

Method: The methodology used in this article included a computerized database review of the latest published information on APD, with an emphasis on the work of established researchers and expert panels, including articles from the American Speech-Language-Hearing Association and the American Academy of Audiology.

Conclusions: The article concludes with the authors’ recommendations for continued research and their views on the appropriate role of the SLP in performing careful screening, making referrals, and supporting intervention.

Computerized Script Training for Aphasia: Preliminary Results

from the American Journal of Speech-Language Pathology

Purpose: This article describes computer software that was developed specifically for training conversational scripts and illustrates its use with 3 individuals with aphasia.

Method: Three participants with chronic aphasia (Broca’s, Wernicke’s, and anomic) were assessed before and after 9 weeks of a computer script training program. For each participant, 3 individualized scripts were developed, recorded on the software, and practiced sequentially at home. Weekly meetings with the speech-language pathologist occurred to monitor practice and assess progress. Baseline and posttreatment scripts were audiotaped, transcribed, and compared to the target scripts for content, grammatical productivity, and rate of production of script-related words. Interviews with the person with aphasia and his or her significant other were conducted at the conclusion of treatment.

Results: All measures (content, grammatical productivity, and rate of production of script-related words) improved for each participant on every script. Two participants gained more than 5 points on the Aphasia Quotient of the Western Aphasia Battery. Five positive themes were consistently identified from the exit interviews—increased verbal communication, improvements in other modalities and situations, communication changes noticed by others, increased confidence, and satisfaction with the software.

Psychometric Evaluation of Condition-Specific Instruments Used to Assess Health-Related Quality of Life, Attitudes, and Related Constructs in Stuttering

from the American Journal of Speech-Language Pathology

Purpose: This study assessed the psychometric properties of instruments used to measure constructs similar to stuttering-specific health-related quality of life. In the stuttering literature, most such instruments were originally intended to measure speakers’ attitudes about, or reactions to, their stuttering.

Method: Seventeen instruments were identified through a comprehensive literature search. Based on specific criteria from previous publications, 10 were selected for complete review and evaluated using 15 measurement standards related to conceptual model, reliability, validity, responsiveness, interpretability (norms), burden (respondent and administrative), depth, and versatility.

Results: None of the available instruments met more than 8 of the 15 measurement standards assessed.

Conclusions: Available instruments do not satisfy psychometric criteria for use in individual or group-level decision making, either as measures of their originally intended constructs or as measures of health-related quality of life. Problems with the conceptual model, reliability, validity, and responsiveness of available instruments, as well as the lack of comprehensive normative data, combine to suggest the need for development and validation of a stuttering-specific health-related quality of life measure.

Comments on Bothe, Davidow, Bramlett, Franic, and Ingham (2006)

from the American Journal of Speech-Language Pathology

Purpose: To critically assess the quality, methodology, and conclusions in A. K. Bothe, J. H. Davidow, R. E. Bramlett, D. M. Franic, and R. J. Ingham’s (2006) systematic review of pharmacological approaches to stuttering.

Method: A. D. Oxman and G. H. Guyatt’s (1988) guidelines for reading literature reviews and A. D. Oxman and G. H. Guyatt’s (1991) criteria for assessing the scientific quality of systematic reviews were adopted to accomplish the purpose.

Results: Bothe et al.’s review was rated on a 7-point scale from extensive flaws on the high end to minimal flaws on the low end of the scale. The ratings varied from poor to good.

Conclusions: We judged Bothe et al.’s review of the pharmacological literature as it pertains to stuttering as flawed in its methodology and conclusions. However, we agree that the existing evidence for the use of pharmacological agents with persons who stutter is insufficient to recommend them in practice. Directions for improving the quality of clinical trials are suggested. In addition, we advocate for the multimethod measurement in stuttering research, including comparison, subjective evaluation, and social impact measures.

Pharmacological Approaches to Stuttering Treatment: Reply to Meline and Harn (2008)

from the American Journal of Speech-Language Pathology

Purpose: To address questions raised by T. Meline and W. E. Harn (2008) in their critique of our previous article (A. K. Bothe, J. H. Davidow, R. E. Bramlett, D. M. Franic, & R. J. Ingham, 2006).

Method: Additional information is provided to address several issues raised by Meline and Harn.

Results and Conclusions: Our previous systematic review omitted 1 relevant article about the use of olanzapine in stuttering, but the minimal effectiveness and the known serious side effects of this drug limit the implications of this omission. While we do not agree with many of Meline and Harn’s critiques of our review, we do agree with them that several larger points raise interesting questions about the structure, analysis, and usefulness of literature reviews in stuttering and in other areas. Fundamentally, we reassert our agreement with Meline and Harn that there is insufficient evidence to support the use of existing pharmacological agents in the treatment of stuttering.

Neuroplasticity and Rehabilitation Research for Speech, Language, and Swallowing Disorders

from the Journal of Speech, Language, and Hearing Research

Purpose: This article introduces a collection of consensus statements regarding the application of neuroplasticity principles to rehabilitation of dysphagia, dysarthria, apraxia, and aphasia.

Translational Research in Aphasia: From Neuroscience to Neurorehabilitation

from the Journal of Speech, Language, and Hearing Research

Purpose: In this article, the authors encapsulate discussions of the Language Work Group that took place as part of the Workshop in Plasticity/NeuroRehabilitation Research at the University of Florida in April 2005.

Method: In this narrative review, they define neuroplasticity and review studies that demonstrate neural changes associated with aphasia recovery and treatment. The authors then summarize basic science evidence from animals, human cognition, and computational neuroscience that is relevant to aphasia treatment research. They then turn to the aphasia treatment literature in which evidence exists to support several of the neuroscience principles.

Conclusion: Despite the extant aphasia treatment literature, many questions remain regarding how neuroscience principles can be manipulated to maximize aphasia recovery and treatment. They propose a framework, incorporating some of these principles, that may serve as a potential roadmap for future investigations of aphasia treatment and recovery. In addition to translational investigations from basic to clinical science, the authors propose several areas in which translation can occur from clinical to basic science to contribute to the fundamental knowledge base of neurorehabilitation. This article is intended to reinvigorate interest in delineating the factors influencing successful recovery from aphasia through basic, translational, and clinical research.

Telehealth Delivery of the Camperdown Program for Adults Who Stutter: A Phase I Trial

from the Journal of Speech, Language, and Hearing Research

Purpose: This Phase I trial investigated the viability of telehealth delivery of the Camperdown Program with adults who stutter. This program involves speech restructuring.

Method: All treatment was conducted remotely with participant–clinician contact occurring by telephone and e-mail.

Results: Ten adults completed the program. The group showed an 82% reduction in stuttering frequency immediately after treatment and a 74% reduction 6 months after treatment. However, there was significant individual variation in response to the program.

Conclusion: These preliminary data suggest that telehealth Camperdown has the potential to provide efficacious treatment for clients who do not have access to traditional face-to-face treatment.

Age Effects on the Process of L2 Acquisition? Evidence From the Acquisition of Negation and Finiteness in L2 German

from Language Learning

It is widely assumed that ultimate attainment in adult second language (L2) learners often differs quite radically from ultimate attainment in child L2 learners. This article addresses the question of whether learners at different ages also show qualitative differences in the process of L2 acquisition. Longitudinal production data from two untutored Russian beginners (ages 8 and 14) acquiring German under roughly similar conditions are compared to published results on the acquisition of German by adult immigrants. The study focuses on the acquisition of negation and finiteness as core domains of German sentence grammar. Adult learners have been shown to produce an early nonfinite learner variety in which utterance organization relies on principles of information structure rather than on target language grammar. They then go through a couple of intermediate steps in which, first, semantically empty verbs (auxiliaries) serve as isolated carriers of finiteness before lexical verbs become finite. Whereas the 14-year-old learner of this case study basically shows a developmental pattern similar to that of adults, the 8-year-old child produces a different order of acquisition: Not only is the development of finite morphology faster, but finite lexical verbs are acquired before auxiliary constructions (Perfekt). Results suggest a stronger tendency for young learners to incrementally assimilate input patterns without relying on analytic steps guided by principles of information organization to the same extent as older learners.

Cognition, Language Contact, and the Development of Pragmatic Comprehension in a Study-Abroad Context

from Language Learning

This study examined two issues: (a) whether there are gains in accurate and speedy comprehension of second language (L2) pragmatic meaning over time and (b) whether the gains are associated with cognitive processing ability and the amount of language contact in an L2 environment. Forty-four college students in a US institution completed three measures three times over a 4-month period: (a) the pragmatic listening test that measured the ability to comprehend implied speaker intentions, (b) the lexical access test that measured ability to make speedy semantic judgment, and (c) the language contact survey that examined the amount of time learners spent in L2 outside the class. The learners’ pragmatic comprehension was analyzed for accuracy (the scores on the pragmatic listening test) and comprehension speed (the average time taken to answer items correctly). Results showed that the learners made significant improvement on comprehension speed but not on accuracy of comprehension. Lexical access speed was significantly correlated with comprehension speed but not with accuracy. The amount of speaking and reading outside class that the students reported on the language contact survey significantly correlated with the gains in comprehension speed but not with accuracy of comprehension.

Role Salience and Anticipated Work–Family Relations Among Young Adults With and Without Hearing Loss

from the Journal of Deaf Studies and Deaf Education

This study examined the effect of hearing status on role salience and anticipated work–family relations among 101 unmarried young adults aged 20–33 years: 35 with hearing loss (19 hard of hearing and 16 deaf) and 66 hearing. Participants completed the Life Role Salience scale, anticipated conflictual relations scale, anticipated facilitory relations scale, and a background questionnaire. The deaf participants demonstrated a significantly higher level of commitment to work but anticipated the significantly lowest level of conflict. Hearing status was a significant variable in predicting anticipated conflictual relations among all participants. Mode of communication was a significant predictor of conflictual relations among the hearing loss group. Implications for theory and practice were discussed.