Altered auditory feedback improves speech intelligibility in individuals diagnosed with Parkinson's disease - A pilot study.

INTRODUCTION: The purpose of the current study was to evaluate speech intelligibility and speech rate in individuals with Parkinson's disease using altered auditory feedback (AAF) in comparison to age-matched healthy controls. Based on prior research, it is hypothesized that the use of AAF will improve participants' speech intelligibility. METHOD: Five individuals with Parkinson's disease (clinical group) and five age-matched healthy controls aged 50 and above participated in this pre/post group experiment. All participants completed reading and monologue tasks with and without AAF. The AAF delayed the participants' auditory feedback by 150 milliseconds and altered it by 1/20 octave. Thirty-two naïve listeners listened to the recorded participants' speech samples (with and without AAF) randomly and rated the participants' speech intelligibility. RESULTS: Results of the mixed model ANOVA revealed that participants in the control group had significantly higher speech intelligibility scores than the participants in the clinical group. Post-hoc tests indicated that only participants in the clinical group were more intelligible with AAF than without AAF. Participants in the clinical group had better speech intelligibility when reading the passage than speaking the monologue. With regards to speech rate, participants spoke more slowly with AAF than without. Finally, there was a negative correlation between speech rate and speech intelligibility. CONCLUSION: The current findings support our hypothesis that AAF improves speech intelligibility in people with Parkinson's disease, though not healthy controls. Future research should evaluate the long-term effect of AAF use on speech intelligibility in people with Parkinson's disease.

The role of lag effect in distributed practice on learning novel vocabulary.

PURPOSE: The purpose of the current study was to investigate the lag effects in two different versions of distributed practice on learning novel language vocabulary. METHOD: Forty-four healthy monolingual English-speaking participants were randomly assigned to two versions of distributed practice. The two versions of distributed practice were created by altering the temporal lag between the practice sessions. Participants in both groups completed a similar practice regimen wherein they practiced 30 French occupations five times each for a total of 150 times. The pre/post-design employed in this experiment involved participants completing baseline, immediate, and delayed retention tests. The outcome measures included a comprehensive multiple-choice test and a written expression task. RESULTS: The findings from the comprehensive and expressive tasks indicated that the learning performance of participants across both groups was better during the immediate retention test compared to the delayed retention test. With regard to the group, participants assigned to the condensed version of distributed practice demonstrated superior learning of the novel vocabulary over participants assigned to the extended version of distributed practice. CONCLUSION: The findings indicate that an increased temporal lag between the practice sessions results in a "non-monotonic function," wherein the learning continues to improve until an optimal lag, after which the learning declines as the lag continues to increase. This line of research will have a substantive impact on service-delivery models in speech-language pathology.

Role of Massed Versus Distributed Practice in Learning Novel Foreign Language Utterances.

The current study compared the role of massed versus distributed practice in learning novel foreign language utterances. Fifty healthy native English-speaking participants were randomly assigned to either massed or distributed practice groups. All participants practiced eight novel French utterances 25 times each for a total of 200 times, with the spacing of practice sessions differing between the two groups. Both the groups completed an immediate retention as well as a delayed retention test. Participants' learning was evaluated based on phonetic accuracy and naturalness of the French utterances. The findings revealed that participants involved in distributed practice demonstrated better learning over participants involved in massed practice. Future research should aim to extrapolate these findings in treating speech disorders.

Role of Constant, Random and Blocked Practice in an Electromyography-Based Oral Motor Learning Task.

PURPOSE: The role of principles of motor learning (PMLs) in speech has received much attention in the past decade. Oral motor learning, however, has not received similar consideration. This study evaluated the role of three practice conditions in an oral motor tracking task. METHOD: Forty-five healthy adult participants were randomly and equally assigned to one of three practice conditions (constant, blocked, and random) and participated in an electromyography-based task. The study consisted of four sessions, at one session a day for four consecutive days. The first three days sessions included a practice phase, with immediate visual feedback, and an immediate retention phase, without visual feedback. The fourth session did not include practice, but only delayed retention testing, lasting 10-15 minutes, without visual feedback. RESULTS: Random group participants performed better than participants in constant and blocked practice conditions on all the four days. Constant group participants demonstrated superior learning over blocked group participants only on day 4. CONCLUSION: Findings indicate that random practice facilitates oral motor learning, which is in line with limb/speech motor learning literature. Future research should systematically investigate the outcomes of random practice as a function of different oral and speech-based tasks.

Speech, language, and hearing function in twins with Alport syndrome: A seven-year retrospective case report.

Alport syndrome is an X-linked syndrome that results in nephritis, renal failure, sensorineural hearing loss, and eye deficits. As a result of sensorineural hearing loss, these individuals are likely to experience difficulties in the area of speech and language. While studies in the past have examined the speech and language characteristics of children with syndromic sensorineural hearing loss, to our knowledge there are no previous studies to have documented the speech and language characteristics of these children on a long-term basis. The current study addresses this limitation by reporting speech, language, hearing, and function of twin brothers with X-linked Alport syndrome across a seven-year period. Information was collected by examining the medical records of the participants as well as through a verbal interview with the participants' guardian. Results revealed that the participants' hearing abilities gradually deteriorated over the seven-year period which affected their speech and language development as well. The kidney function tests revealed significant presence of hematuria (blood in the urine) as well as proteinuria (protein in the urine) suggesting chronic kidney dysfunction. This longitudinal study demonstrates the functional relationship between the kidneys and the cochlea, although they appear to be independent of one another. As individuals with Alport syndrome exhibit systemic complications, interdisciplinary collaboration is essential among health care providers including audiologists, speech-language pathologists, nephrologists, and ophthalmologist to promote evidence-based practice.

Functioning of medial olivocochlear bundle in right- and left-handed individuals.

Functional symmetry of medial olivocochlear bundle (MOCB) as a function of handedness remains to be well investigated. The current study aimed to assess the functional symmetry of MOCB through contralateral inhibition of otoacoustic emissions (OAEs) in right- and left-handed individuals. Thirteen left-handed and 13 right-handed individuals in the age range of 19-25 years participated. Behavioural experiment involved measuring speech perception in noise and vocal reaction time. Physiological experiment involved measuring the contralateral inhibition of OAEs in both the ears of participants. Findings of the current study revealed lack of functional asymmetry in right- as well as left-handed individuals. Results of the current study suggest that right- as well as left-handed individuals do not demonstrate functional asymmetry at the level of descending auditory pathways unlike the higher cortical centres.

Is There an Interaction between Task Complexity and Practice Variability in Speech-Motor learning?

BACKGROUND: Prior studies have investigated the influence of principles of motor learning (PMLs) on speech-motor learning. However, the interactive effect of different PMLs on speech-motor learning remains unknown. PURPOSE: This study is aimed at investigating the interaction of 2 PMLs, that is, practice variability and task complexity and their influence on speech-motor learning. METHOD: Forty healthy individuals (aged 18-30 years) were randomly and equally allocated to 2 groups where they had to either practice a simple (simple group) or a complex phrase (complex group). Two levels of practice variability (constant and variable) were considered in training participants in simple and complex groups. Participants practiced 50 practice trials of either complex or simple phrase during the first 2 days. At the end of training on each day, participants produced 10 trials of the phrase they practiced without feedback. On the third day, participants returned for a delayed retention test. The participant utterances on all the 3 days were recorded for later analysis. RESULTS: Data analysis revealed that there was no major effect of practice condition, and there was no interaction of task complexity and practice condition. However, there was an interaction between data collection points and complexity. CONCLUSION: The findings suggest that irrespective of the complexity of the to-be-learned speech task, there is no preponderance of variable over constant practice, which contradicts the findings of the non-speech-motor learning literature.

Efficacy of auditory-verbal therapy in children with hearing impairment: A systematic review from 1993 to 2015.

OBJECTIVES: Auditory verbal therapy (AVT) is one of the primary treatment approaches for developing spoken language in children with hearing impairment (HI), but its outcomes have not been thoroughly investigated. The current study aimed to systematically review past studies investigating AVT outcomes in children with HI. METHODS: A systematic search was conducted in six databases. Fourteen articles that met the final inclusion criteria were grouped under three categories based on the outcome measures: receptive and expressive language development, auditory/speech perception and mainstreaming. RESULTS: Articles under "receptive and expressive language development" category indicated AVT can even help children with HI beyond three years of age to develop age appropriate language skills and catch up with their hearing peers. Articles under "auditory /speech perception" category suggested that children receiving AVT can learn to recognize words accurately even in the presence of background noise. Articles grouped under "mainstreaming" category indicated that children receiving AVT can be successfully mainstreamed. CONCLUSION: Although studies suggest that AVT can have a positive impact on developing speech and language skills in children with HI, it is difficult to generalize these findings due to limited evidence. Future studies should utilize well-controlled group designs to minimize the role of external variables as well as strengthen the evidence-base for AVT.

Are individuals with Parkinson's disease capable of speech-motor learning? - A preliminary evaluation.

INTRODUCTION: The benefits of different practice conditions in limb-based rehabilitation of motor disorders are well documented. Conversely, the role of practice structure in the treatment of motor-based speech disorders has only been minimally investigated. Considering this limitation, the current study aimed to investigate the effectiveness of selected practice conditions in spatial and temporal learning of novel speech utterances in individuals with Parkinson's disease (PD). METHODS: Participants included 16 individuals with PD who were randomly and equally assigned to constant, variable, random, and blocked practice conditions. Participants in all four groups practiced a speech phrase for two consecutive days, and reproduced the speech phrase on the third day without further practice or feedback. RESULTS: There were no significant differences (p > 0.05) between participants across the four practice conditions with respect to either spatial or temporal learning of the speech phrase. Overall, PD participants demonstrated diminished spatial and temporal learning in comparison to healthy controls. Tests of strength of association between participants' demographic/clinical characteristics and speech-motor learning outcomes did not reveal any significant correlations. CONCLUSIONS: The findings from the current study suggest that repeated practice facilitates speech-motor learning in individuals with PD irrespective of the type of practice. Clinicians need to be cautious in applying practice conditions to treat speech deficits associated with PD based on the findings of non-speech-motor learning tasks.

A systematic review of treatment intensity in speech disorders.

PURPOSE: Treatment intensity (sometimes referred to as "practice amount") has been well-investigated in learning non-speech tasks, but its role in treating speech disorders has not been largely analysed. This study reviewed the literature regarding treatment intensity in speech disorders. METHOD: A systematic search was conducted in four databases using appropriate search terms. Seven articles from a total of 580 met the inclusion criteria. The speech disorders investigated included speech sound disorders, dysarthria, acquired apraxia of speech and childhood apraxia of speech. All seven studies were evaluated for their methodological quality, research phase and evidence level. RESULT: Evidence level of reviewed studies ranged from moderate to strong. With regard to the research phase, only one study was considered to be phase III research, which corresponds to the controlled trial phase. The remaining studies were considered to be phase II research, which corresponds to the phase where magnitude of therapeutic effect is assessed. Results suggested that higher treatment intensity was favourable over lower treatment intensity of specific treatment technique(s) for treating childhood apraxia of speech and speech sound (phonological) disorders. CONCLUSION: Future research should incorporate randomised-controlled designs to establish optimal treatment intensity that is specific to each of the speech disorders.

Auditory interference control in children with learning disability: An exploratory study.

OBJECTIVES: The current study aimed to compare the auditory interference control of participants with Learning Disability (LD) to a control group on two versions of an auditory Stroop task. METHODS: A group of eight children with LD (clinical group) and another group of eight typically developing children (control group) served as participants. All the participants were involved in a semantic and a gender identification-based auditory Stroop task. Each participant was presented with eight different words (10 times) that were pre-recorded by a male and a female speaker. The semantic task required the participants to ignore the speaker's gender and attend to the meaning of the word, and vice-versa for the gender identification task. The participants' performance accuracy and reaction time (RT) was measured on both the tasks. RESULTS: Control group participants significantly outperformed the clinical group participants on both the tasks with regard to performance accuracy as well as RT. CONCLUSION: The results suggest that children with LD have problems in suppressing irrelevant auditory stimuli and focusing on the relevant auditory stimuli. This can be attributed to the auditory processing problems in these children.

The use of non-speech oral-motor exercises among Indian speech-language pathologists to treat speech disorders: An online survey.

OBJECTIVE: Previous surveys in the United States of America (USA), the United Kingdom (UK), and Canada have indicated that most of the speech-language pathologists (SLPs) tend to use non-speech oral-motor exercises (NSOMEs) on a regular basis to treat speech disorders.At present, there is considerable debate regarding the clinical effectiveness of NSOMEs. The current study aimed to investigate the pattern and extent of usage of NSOMEs among Indian SLPs. METHOD: An online survey intended to elicit information regarding the use of NSOMEs was sent to 505 members of the Indian Speech and Hearing Association. The questionnaire consisted of three sections. The first section solicited demographic information, the second and third sections solicited information from participants who did and did not prefer to use NSOMEs, respectively. Descriptive statistics were employed to analyse the responses that were clinically relevant. RESULTS: A total of 127 participants responded to the survey. Ninety-one percent of the participants who responded to the survey indicated that they used NSOMEs. CONCLUSION: The results suggested that the percentage of SLPs preferring to use NSOMEsis similar to the findings of surveys conducted in the USA, the UK, and Canada. The Indian SLPs continue to use NSOMEs based on a multitude of beliefs. It is important for SLPs to incorporate the principles of evidence-based practice while using NSOMEs to provide high quality clinical care.

Brief report: an unusual manifestation of diagnostic overshadowing of pervasive developmental disorder--not otherwise specified: a five year longitudinal case study.

Children with communication disorders present with a range of comorbid conditions. Occasionally one of the comorbid conditions manifests so strongly that the primary condition goes unnoticed by the clinician. This tendency to overlook comorbid health problems in the presence of a disability is referred to as diagnostic overshadowing. This is a five-year follow up case study of a 9-year-old female child. The child was initially diagnosed to have Separation anxiety disorder (SAD), but during the course of follow up she began to exhibit features of pervasive developmental disorder-not otherwise specified (PDD-NOS). This case report throws light on the severity of SAD which overshadowed PDD-NOS. Importance of follow-up and the need for a multidisciplinary team to be sensitive to the phenomenon of diagnostic overshadowing is discussed.

Recovery of speech following total glossectomy: an acoustic and perceptual appraisal.

This study involved an acoustic and perceptual analysis of the speech produced by a 31-year-old female following total glossectomy. Speech samples were collected on three occasions within the first 3 months following glossectomy. Vowel articulation was examined acoustically as a function of vowel space and the Euclidean distance separating corner vowels. Perceptual analyses involved presentation of the participant's CV productions to 30 healthy adult listeners who made forced-choice identifications of consonant type. Acoustic analysis revealed improvements in vowel space area and an increase in the Euclidean distances. The perceptual results revealed a statistically significant deterioration in consonants over the 3-month period with anterior sounds being perceived more correctly than medial and posterior sounds. The current study highlights the variable nature of speech following glossectomy, with greater improvements in vowel articulation compared to consonant articulation during the earliest stages of surgical recovery.

Acoustic estimates of respiration in the pain cries of newborns.

OBJECTIVE: The purpose of the present study was to examine the temporal features of pain-elicited crying demonstrated by healthy full term infants to estimate (1) the respiratory rate during cry and (2) the inspiratory and expiratory phase composition of the cry respiratory cycle. PATIENTS AND METHODS: The pain-elicited cries of 12 newborn infants were recorded within the first 2 weeks following birth. A complete crying episode was analyzed for each infant and acoustically measured for the number and duration of inspiratory and expiratory cry components. These components were then used to estimate the respiratory rate of infant crying, as well as the inspiratory and expiratory phase composition of the cry respiratory cycles. RESULTS: Acoustic analysis revealed that the average rate of crying was 57 breaths min⁻¹ with the inspiratory phase contributing 27% to the overall respiratory cycle. However, considerable variability was found across infants with distinct patterns of respiration associated with high versus low respiratory rates. CONCLUSIONS: The respiratory patterns associated with pain cries is highly variable and may be associated with variations in stress-arousal, strength of emotional expression, and overall fitness. This study supports the notion that the respiratory activity surrounding newborn infant crying is unique to the type of cry sampled.