The effectiveness of SpeechEasy during situations of daily living

A multiple single-subject design was used to examine the effects of SpeechEasy on stuttering frequency in the laboratory and in longitudinal samples of speech produced in situations of daily living (SDL). Seven adults who stutter participated, all of whom had exhibited at least 30% reduction in stuttering frequency while using SpeechEasy during previous laboratory assessments. For each participant, speech samples recorded in the laboratory and SDL during device use were compared to samples obtained in those settings without the device. In SDL, stuttering frequencies were recorded weekly for 9-16 weeks during face-to-face and phone conversations. Participants also provided data regarding device tolerance and perceived benefits. Laboratory assessments were conducted at the beginning and the end of the longitudinal data collection in SDL. All seven participants exhibited reduced stuttering in self-formulated speech in the Device compared to No-device condition during the first laboratory assessment. In the second laboratory assessment, four participants exhibited less stuttering and three exhibited more stuttering with the device than without. In SDL, five of seven participants exhibited some instances of reduced stuttering when wearing the device and three of these exhibited relatively stable amounts of stuttering reduction during long-term use. Five participants reported positive changes in speaking-related attitudes and perceptions of stuttering. Further investigation into the short- and long-term effectiveness of SpeechEasy in SDL is warranted. Educational objectives: The reader will be able to summarize: (1) issues pertinent to evaluating treatment benefits of wearable fluency aids and evaluate (2) the effect of SpeechEasy on stuttering frequency and the perceived benefits of device use in situations of daily living, as assessed weekly over the course of 9-16 weeks of wear, for seven adults who stutter.     

The effect of SpeechEasy on stuttering frequency, speech rate, and speech naturalness

The effects of SpeechEasy on stuttering frequency, stuttering severity self-ratings, speech rate, and speech naturalness for 31 adults who stutter were examined. Speech measures were compared for samples obtained with and without the device in place in a dispensing setting. Mean stuttering frequencies were reduced by 79% and 61% for the device compared to the control conditions on reading and monologue tasks, respectively. Mean severity self-ratings decreased by 3.5 points for oral reading and 2.7 for monologue on a 9-point scale. Despite dramatic reductions in stuttering frequency, mean global speech rates in the device condition increased by only 8% in the reading task and 15% for the monologue task, and were well below normal. Further, complete elimination of stuttering was not associated with normalized speech rates. Nevertheless, mean ratings of speech naturalness improved markedly in the device compared to the control condition and, at 3.3 and 3.2 for reading and monologue, respectively, were only slightly outside the normal range. These results show that SpeechEasy produced improved speech outcomes in an assessment setting. However, findings raise the issue of a possible contribution of slowed speech rate to the stuttering reduction effect, especially given participants' instructions to speak chorally with the delayed signal as part of the active listening instructions of the device protocol. Study of device effects in situations of daily living over the long term is necessary to fully explore its treatment potential, especially with respect to long-term stability. Educational objectives: The reader will be able to discuss and evaluate: (1) issues pertinent to evaluating treatment benefits of fluency aids and (2) the effects of SpeechEasy on stuttering frequency, speech rate, and speech naturalness during testing in a dispensing setting for a relatively large sample of adults who stutter.     

Long-term effectiveness of the SpeechEasy fluency-enhancement device

The SpeechEasy has been found to be an effective device for reduction of stuttering frequency for many people who stutter (PWS); published studies typically have compared stuttering reduction at initial fitting of the device to results achieved up to one year later. This study examines long-term effectiveness by examining whether effects of the SpeechEasy were maintained for longer periods, from 13 to 59 months. Results indicated no significant change for seven device users from post-fitting to the time of the study (t = ?.074, p = .943); however, findings varied greatly on a case-by-case basis. Most notably, when stuttering frequency for eleven users and former users, prior to device fitting, was compared to current stuttering frequency while not wearing the device, the change over time was found to be statistically significant (t = 2.851, p = .017), suggesting a carry-over effect of the device. There was no significant difference in stuttering frequency when users were wearing versus not wearing the device currently (t = 1.949, p = 0.92). Examinations of these results, as well as direction for future research, are described herein.Educational objectives: The reader will be able to: (a) identify and briefly describe two types of altered auditory feedback which the SpeechEasy incorporates in order to help reduce stuttering; (b) describe the carry-over effect found in this study, suggest effectiveness associated with the device over a longer period of time than previously reported, as well as its implications, and (c) list factors that might be assessed in future research involving this device in order to more narrowly determine which prospective users are most likely to benefit from employing the SpeechEasy.     

Some effects of the Edinburgh Masker on stuttering during oral reading and spontaneous speech

This study assessed the effect of a voice-activated masking unit, known as the Edinburgh Masker, on the speech of four stutterers during oral reading and spontaneous speech. The results show that one stutterer reduced stuttering almost completely whenever the masker was activated. Two subjects showed either marginal or temporary reductions of stuttering during one speaking condition but showed no change in the other condition. The other subject reduced stuttering only during spontaneous speech. No reduction in stuttering was associated with reduced speech rate. A perceptual analysis procedure conducted to assess for altered speech quality during masking conditions found changes in speech quality were evident in two subjects. The clinical implications of these findings are discussed.     

Listener perceptions of stuttering across two presentation modes: a quantitative and qualitative approach

The purpose of this study was to compare participants' quantitative and qualitative judgments of various forms and frequencies of stuttering, during either audiovisual or audio-only presentation modes. A total of 64 participants voluntarily agreed to participate in the study. Each participant was randomly assigned and exposed to only one of the four conditions of varying stuttering severity levels. The assigned speech sample was presented to the participant in either the audiovisual or audio-only mode. After watching or listening to the sample, participants completed a six-item Likert scale and were asked four open-ended questions. Comments made by listeners were developed into positive and negative comments as well as sorted into five theme clusters. The data analyses revealed a number of non-significant differences across mean Likert scale ratings for the six statements and for the number of positive and negative comments between the two presentation modes. However, the results provided partial support for the notion that as the frequency of stuttering increases, listeners tend to make increasingly more negative comments about the speaker. Additionally, there were no clear differences in comments across the five theme clusters between the two presentation modes. The findings suggest that the type of presentation mode does not appear to affect listeners' perceptions of stuttering to the same extent that stuttering severity does. EDUCATIONAL OBJECTIVES: The reader will be able to: (1) describe how listeners perceive and react to various frequencies of stuttering; (2) explain how audiovisual versus audio-only samples impact listener perceptions of stuttering and (3) provide examples of the ways in which qualitative data can enhance the understanding of how listeners react to various levels of stuttering.     

The effects of simulated stuttering and prolonged speech on the neural activation patterns of stuttering and nonstuttering adults

Functional magnetic resonance imaging was used to investigate the neural correlates of passive listening, habitual speech and two modified speech patterns (simulated stuttering and prolonged speech) in stuttering and nonstuttering adults. Within-group comparisons revealed increased right hemisphere biased activation of speech-related regions during the simulated stuttered and prolonged speech tasks, relative to the habitual speech task, in the stuttering group. No significant activation differences were observed within the nonstuttering participants during these speech conditions. Between-group comparisons revealed less left superior temporal gyrus activation in stutterers during habitual speech and increased right inferior frontal gyrus activation during simulated stuttering relative to nonstutterers. Stutterers were also found to have increased activation in the left middle and superior temporal gyri and right insula, primary motor cortex and supplementary motor cortex during the passive listening condition relative to nonstutterers. The results provide further evidence for the presence of functional deficiencies underlying auditory processing, motor planning and execution in people who stutter, with these differences being affected by speech manner.     

Differential levels of speech and manual dysfluency in adults who stutter during simultaneous drawing and speaking tasks

We examined the disruptive effects of stuttering on manual performance during simultaneous speaking and drawing tasks. Fifteen stuttering and fifteen non-stuttering participants drew continuous circles with a pen on a digitizer tablet under three conditions: silent (i.e., neither reading nor speaking), reading aloud, and choral reading (i.e., reading aloud in unison with another reader). We counted the frequency of stuttering events in the speaking tasks and measured pen stroke duration and pen stroke dysfluency (normalized jerk) in all three tasks. The control group was stutter-free and did not increase manual dysfluency in any condition. In the silent condition, the stuttering group performed pen movements without evidence of dysfluency, similar to the control group. However, in the reading aloud condition, the stuttering group stuttered on 12% of the syllables and showed increased manual dysfluency. In the choral reading condition stuttering was virtually eliminated (reduced by 97%), but manual dysfluency was reduced by only 47% relative to the reading aloud condition. Trials where more stuttered events were generally positively correlated with higher manual dysfluency. The results are consistent with a model in which episodes of stuttering and motor dysfluency are related to neural interconnectivity between manual and speech processes.     

Voluntary stuttering suppresses true stuttering: a window on the speech perception-production link

In accord with a proposed innate link between speech perception and production (e.g., motor theory), this study provides compelling evidence for the inhibition of stuttering events in people who stutter prior to the initiation of the intended speech act, via both the perception and the production of speech gestures. Stuttering frequency during reading was reduced in 10 adults who stutter by approximately 40% in three of four experimental conditions: (1) following passive audiovisual presentation (i.e., viewing and hearing) of another person producing pseudostuttering (stutter-like syllabic repetitions) and following active shadowing of both (2) pseudostuttered and (3) fluent speech. Stuttering was not inhibited during reading following passive audiovisual presentation of fluent speech. Syllabic repetitions can inhibit stuttering both when produced and when perceived, and we suggest that these elementary stuttering forms may serve as compensatory speech gestures for releasing involuntary stuttering blocks by engaging mirror neuronal systems that are predisposed for fluent gestural imitation.     

Regional brain activity change predicts responsiveness to treatment for stuttering in adults

Developmental stuttering is known to be associated with aberrant brain activity, but there is no evidence that this knowledge has benefited stuttering treatment. This study investigated whether brain activity could predict progress during stuttering treatment for 21 dextral adults who stutter (AWS). They received one of two treatment programs that included periodic H₂¹⁵O PET scanning (during oral reading, monologue, and eyes-closed rest conditions). All participants successfully completed an initial treatment phase and then entered a phase designed to transfer treatment gains; 9/21 failed to complete this latter phase. The 12 pass and 9 fail participants were similar on speech and neural system variables before treatment, and similar in speech performance after the initial phase of their treatment. At the end of the initial treatment phase, however, decreased activation within a single region, L. putamen, in all 3 scanning conditions was highly predictive of successful treatment progress.     

A novel approach for measuring social participation in adults who stutter

This paper reports a preliminary study which trialled a novel approach for measuring speech output and social participation. The amount of phonation was accumulated via an objective measure called an Ambulatory Phonation Monitor (APM).Purpose(1) To establish whether adults who stutter will tolerate wearing an APM for an extended period of time (three days), (2) to test whether the APM can accumulate useful data about the amount of phonation adults who stutter produce in the course of a normal day and (3) to examine a possible relationship between stuttering severity and amount of phonation.MethodThree adults who stutter wore an APM for three consecutive days during their waking hours. Each completed a questionnaire regarding the device and kept a speech diary outlining daily speaking activities and self-reported stuttering severity. APM data regarding amount of phonation was collected, analysed and compared with the participants’ speech diaries.ResultsEach adult tolerated wearing the APM and while they felt comfortable speaking wearing the device, it was somewhat cumbersome. Variations in the amount of speaking across each day and in different speaking situations were evident. For two participants there was a positive correlation between phonation time and severity rating.ConclusionsPreliminary data suggests that the APM can provide valuable information about the amount adults who stutter speak. The APM is sufficiently sensitive to differentiate variations in the amount of phonation during different speaking situations. These favourable preliminary results suggest the value of a larger scale study.Educational Objectives: The reader will be able to: (a) describe the different aspects of stuttering currently routinely measured in clinical practice; (b) discuss the limitations of current measurement procedures; (c) discuss the advantages of speech measures obtained by an Ambulatory Phonation Monitor APM); (d) describe the perspectives of adults who stutter who have worn an APM to measure phonation time.     

Exposure therapy for social anxiety disorder in people who stutter: An exploratory multiple baseline design

Background & objectives: Social anxiety disorder (SAD) is a debilitating condition, and approximately half of adults who stutter have SAD. Cognitive-behavioral therapy (CBT) has shown promise in decreasing social anxiety symptoms among adults who stutter, but exposure, arguably the essential component for successful CBT for SAD, has been understudied and underemphasized. Aims of this study were to develop an exposure therapy protocol designed specifically for people who stutter and have SAD and evaluate its potential efficacy in reducing social anxiety and stuttering severity using a multiple baseline design.Methods: Six participants received ten sessions of exposure therapy. Participants reported daily social anxiety, and social distress and stuttering severity were evaluated at major assessment points.Results: There were substantial reductions in social anxiety and considerable improvements in affective, behavioral, and cognitive experiences of stuttering. No consistent change was observed for stuttering frequency. Gains were mostly maintained after six-months.Conclusions: Results suggest that the novel exposure approach may decrease social distress, but not necessarily influence speech fluency. These findings underscore the importance of the assessment and treatment of SAD among adults who stutter and suggest that the integration of care between clinical psychologists and speech-language pathologists may prove beneficial for this population.     

Common features of fluency-evoking conditions studied in stuttering subjects and controls: an H(2)15O PET study

We used H(2)15O PET to characterize the common features of two successful but markedly different fluency-evoking conditions -- paced speech and singing -- in order to identify brain mechanisms that enable fluent speech in people who stutter. To do so, we compared responses under fluency-evoking conditions with responses elicited by tasks that typically elicit dysfluent speech (quantifying the degree of stuttering and using this measure as a confounding covariate in our analyses). We evaluated task-related activations in both stuttering subjects and age- and gender-matched controls. Areas that were either uniquely activated during fluency-evoking conditions, or in which the magnitude of activation was significantly greater during fluency-evoking than dysfluency-evoking tasks included auditory association areas that process speech and voice and motor regions related to control of the larynx and oral articulators. This suggests that a common fluency-evoking mechanism might relate to more effective coupling of auditory and motor systems -- that is, more efficient self-monitoring, allowing motor areas to more effectively modify speech. These effects were seen in both PWS and controls, suggesting that they are due to the sensorimotor or cognitive demands of the fluency-evoking tasks themselves. While responses seen in both groups were bilateral, however, the fluency-evoking tasks elicited more robust activation of auditory and motor regions within the left hemisphere of stuttering subjects, suggesting a role for the left hemisphere in compensatory processes that enable fluency. EDUCATIONAL OBJECTIVES: The reader will learn about and be able to: (1) compare brain activation patterns under fluency- and dysfluency-evoking conditions in stuttering and control subjects; (2) appraise the common features, both central and peripheral, of fluency-evoking conditions; and (3) discuss ways in which neuroimaging methods can be used to understand the pathophysiology of stuttering.     

Vocal changes in stutterers and nonstutterers during monotoned speech

For years, reports have circulated that stutterers experience marked decrements in their stuttering when they speak or read in monotone. Wingate has suggested that the ameliorative effects of various novel speaking conditions on stuttering can be attributed to modifications in vocalization induced by such conditions. The present study was conducted to see whether this explanation would extend to monotoned speech as well. Ten teenage and adult stutterers and 10 normal speakers were tested in control and monotone reading conditions. Dependent measures were the frequencies of disfluency and stuttering, fundamental frequency, fundamental frequency standard deviation, vocal SPL, vocal SPL standard deviation, and fluent reading rate. Only within-group statistical comparisons were made, because members of the two groups could not be matched pairwise along critical vocal parameters. The major findings of this study indicated that across the two conditions, both groups significantly reduced their fundamental frequency, fundamental frequency standard deviation, vocal SPL and vocal SPL standard deviation. Only the stutterers exhibited a significant decrement in disfluency and stuttering. The normals did not evince enough disfluency in the control condition for a reduction to occur during monotoning. Neither group effected a reduction in fluent reading rates. These and other findings and interpretations are discussed relative to Wingate's modified vocalization hypothesis.     

Common features of fluency-evoking conditions studied in stuttering subjects and controls: an H2O PET study

We used H₂¹⁵O PET to characterize the common features of two successful but markedly different fluency-evoking conditions — paced speech and singing — in order to identify brain mechanisms that enable fluent speech in people who stutter. To do so, we compared responses under fluency-evoking conditions with responses elicited by tasks that typically elicit dysfluent speech (quantifying the degree of stuttering and using this measure as a confounding covariate in our analyses). We evaluated task-related activations in both stuttering subjects and age- and gender-matched controls.

Areas that were either uniquely activated during fluency-evoking conditions, or in which the magnitude of activation was significantly greater during fluency-evoking than dysfluency-evoking tasks included auditory association areas that process speech and voice and motor regions related to control of the larynx and oral articulators. This suggests that a common fluency-evoking mechanism might relate to more effective coupling of auditory and motor systems — that is, more efficient self-monitoring, allowing motor areas to more effectively modify speech.

These effects were seen in both PWS and controls, suggesting that they are due to the sensorimotor or cognitive demands of the fluency-evoking tasks themselves. While responses seen in both groups were bilateral, however, the fluency-evoking tasks elicited more robust activation of auditory and motor regions within the left hemisphere of stuttering subjects, suggesting a role for the left hemisphere in compensatory processes that enable fluency.

Educational objectives: The reader will learn about and be able to: (1) compare brain activation patterns under fluency- and dysfluency-evoking conditions in stuttering and control subjects; (2) appraise the common features, both central and peripheral, of fluency-evoking conditions; and (3) discuss ways in which neuroimaging methods can be used to understand the pathophysiology of stuttering.     

Parkinsonian speech disfluencies: effects of L-dopa-related fluctuations

The excess dopamine theory of stuttering (Wu et al., 1997) contends that stuttering may be related to excess levels of the neurotransmitter dopamine in the brain. As Parkinson's disease (PD) patients commonly exhibit changes in dopamine levels accompanied by changes in motor performance, the present study examined disfluency in PD patients to gain information on the role of dopamine in speech disfluencies. Nine PD patients with no history of developmental stuttering were recorded once before and twice after taking their morning medication (on separate days). They read a passage and produced a monologue. Within-word and overall speech disfluencies were calculated at each recording. Through motor testing, it was inferred that participants had relatively low dopamine levels before taking medication, and relatively high dopamine levels after taking medication. There were no group changes in disfluency levels when the low-dopamine and high-dopamine states were compared. There were, however, significant differences in percent disfluencies between the PD participants and age-matched controls. The results of this study do not strongly support the excess dopamine theory of stuttering. Rather, the disfluency changes exhibited by individual participants support a hypothesis that speech disfluencies may be related to increases or decreases in dopamine levels in the brain. EDUCATIONAL OBJECTIVES: The reader will learn about: (1). the characteristics of disfluent speech exhibited by speakers with Parkinson's disease. (2). The effect of L-dopa based medications on disfluencies of Parkinsonian speakers. (3). The complex role brain dopamine levels may play in disfluent speaking behavior.     

Genetic and environmental effects on stuttering: a twin study from Finland

The present study explored the prevalence of self-reported stuttering in a Finnish twin population and examined the extent to which the variance in liability to stuttering was attributable to genetic and environmental effects. We analyzed data of 1728 Finnish twins, born between 1961 and 1989. The participants were asked to complete a questionnaire on speech, language, and voice. In two of the questions they were asked to report the occurrence of childhood and present stuttering of their own and that of their sibling. According to the results, 2.3% (52) of the participants were reported to have stuttered as children and 28.8% of them (15) were reported to continue to stutter in adulthood. There was no significant gender difference in the prevalence of stuttering in either childhood or adulthood. For childhood stuttering, the tetrachoric correlation was higher for monozygotic pairs (r=.74) than for dizygotic pairs (r=.27). By means of structural equation modeling it was found that 82% of the variance in liability to childhood stuttering was attributable to additive genetic effects, with the remaining 18% due to non-shared environmental effects. In conclusion, the results of the present study confirm findings from prior studies and support a strong genetic and only a moderate non-shared environmental effect on stuttering. Potential small differences in the prevalence of stuttering in different populations are suggested by our data. EDUCATIONAL OBJECTIVES: The reader will be able to recognize the contribution of genetic and environmental effects on stuttering.     

Behavioral engineering: stuttering as a function of stimulus duration during speech synchronization

Past studies have shown that stuttering is eliminated when speech is synchronized with a metronomic beat, but the speech sounds artificial. The present study investigated the effect of increasing the duration of these individual stimulus beats with the stimulus-off period constant at 1 sec. When subjects were instructed to speak during the stimulus-on period, stuttering was an inverse function of stimulus duration, indicating that the known metronome effect on stuttering is one point on a continuum of effective rhythm procedures. The "naturalness" of speech increased as the stimulus duration increased up to durations of about 2 sec, and then decreased. At optimal values, stuttering was greatly reduced and naturalness and rapidity of speech were retained. These optimal values effectively controlled stuttering in a field test that used two types of specially designed portable instruments, one of which produced a tactual stimulus and the other an auditory stimulus.     

Stuttering: A multidimensional treatment and evaluation package

A regulated breathing method associated with systematic desensitization and cognitive restructuring was applied to eight adult stutters. Behavioral measures (percentage of stuttered syllable [%SS] and rate of speech) were taken during telephone, interview, and public speaking situations using both obtrusive and unobtrusive conditions. Cognitive and subjective assessment included the Erickson Scale of Communication Attitudes, an irrational beliefs scale, self-efficacy perception, and the percentage of improvement reported by the stutterers. Eight adult nonstutterers were also assessed in identical conditions and compared with the treated subjects in the purpose of a social validation perspective. Results showed that the treatment package significantly reduced stuttering at post-test, and therapeutic gains were maintained at 6 month follow-up study. On the %SS, no significant difference emerged at follow-up between treated stutterers and normals. The multicomponent treatment appears to be a successful treatment for stuttering.