Dysarthria following acute ischemic stroke: Prospective evaluation of characteristics, type and severity.

BACKGROUND: Dysarthria is a common symptom following stroke and represents an important cause of functional impairment in stroke patients. A better characterization of dysarthria could facilitate differential diagnosis and optimize healthcare service distribution. AIM: To determine the speech characteristics, dysarthria type and severity in the acute phase following ischemic stroke in a comprehensive stroke centre. METHODS & PROCEDURES: First-ever ischemic stroke patients consecutively admitted to the Stroke Unit of Ghent University Hospital were included in this prospective clinical study between March 2018 and October 2019. All participants admitted to the Stroke Unit were screened for dysarthria by a speech-language pathologist within 72 h after admission. When dysarthria was identified, speech characteristics were evaluated via auditory-perceptual assessment and objective measurement of acoustic parameters. Dysarthria type was determined based on the Mayo Classification System. Severity of impairment was scored at function and activity level using the Radboud Dysarthria Assessment and the evaluation of speech intelligibility at sentence level using the Dutch Speech Intelligibility Assessment. In addition, dysarthria recovery was separately evaluated in all participants using the National Institutes of Health Stroke Scale (NIHSS) at hospital admission, day 3 ± 2 and day 7. OUTCOMES & RESULTS: A total of 67 out of 151 participants (44%; mean age = 69 years; SD = 13; 28 females) were diagnosed with dysarthria in the acute phase following stroke. Standardized assessments were possible in 72% (48/67) of participants. Imprecise articulation of consonants, harsh voice quality and audible inspiration were the most frequent observed speech characteristics. The acoustic parameters maximum phonation time and maximum loudness deviated most from normative values. Unilateral upper motor neuron (UUMN) was the main dysarthria type present in 52% (25/48) of participants. A total of 58% (28/48) and 71% (34/48) of participants had no/minimal/mild difficulties at the functional and activity levels, respectively. Speech intelligibility was mildly impaired (median = 91%; IQR = 73-97). According to the NIHSS, sub-item speech score at hospital admission, 46% (70/151) of participants had dysarthria, of which half recovered completely from their dysarthria within 1 week after stroke symptom onset. CONCLUSIONS & IMPLICATIONS: UUMN was the dominant dysarthria type, and the majority of participants had a mild dysarthria. Half the participants showed complete recovery within 1 week following symptom onset. The observed speech characteristics mainly reflect impairments in the subsystem's articulation, phonation and respiration. Objective measurements of acoustic parameters corroborate these findings. Future research should focus on longitudinal assessment to investigate recovery of symptoms and the long-term impact of dysarthria on social participation. What this paper adds What is already known on the subject There are few data concerning the presentation of dysarthria following acute ischemic stroke. Moreover, previous research did not include objective measurements of speech characteristics and dysarthria severity. There was a need to determine prospectively speech characteristics, dysarthria type and severity in a stroke population using standardized assessments. What this paper adds to existing knowledge The findings of this study show a high prevalence of dysarthria following acute ischemic stroke. This study confirms previous findings that the speech of dysarthric patients following acute ischemic stroke was mostly characterized by imprecise articulation of consonants, a harsh voice quality and audible inspiration. The results of the objective measures confirm these findings. We added evidence that UUMN is the most prevalent dysarthria type in a stroke population, and that the majority of participants had mild dysarthria. A high rate of dysarthria recovery was seen in the first week following symptom onset. What are the potential or actual clinical implications of this work? The findings of this study contribute to the limited research performed regarding post-stroke dysarthria. The results can help optimize the distribution of healthcare resources. The majority of participants have a mild dysarthria, making the identification of the specific needs of this group an important area of concern. The evaluation of impaired speech subsystems and characteristics, especially supplemented with objective measures of acoustic parameters, and the classification of the type and severity of dysarthria can be helpful to monitor early progress in the acute phase post-stroke.

The feasibility, usability and acceptability of a tablet-based aphasia therapy in the acute phase following stroke.

QUESTION: Independent practice via an application with a language exercise program for aphasia, as an add-on to conventional care can be a good solution to intensify aphasia therapy. The aim of this prospective trial was to investigate the feasibility, usability and acceptability of the newly-developed aphasia exercise program in the 'Speech Therapy App (STAPP)' in the acute phase post-stroke. METHODS: All eligible people with aphasia following stroke (<2 weeks post-stroke) admitted to the Stroke Unit of Ghent University Hospital were recruited in this prospective clinical trial between September 2018 and December 2019. After linguistic assessments and two short training sessions, participants were asked to practice independently with 'STAPP' for at least 30 min/day during hospitalization. Exercises were individually tailored and adjusted if necessary. Outcome was measured by recruitment, adherence and retention rates, usability questionnaires and a visual analogue scale for satisfaction. RESULTS: Twenty-five (mean age 65 years (SD = 17), 14 females) of 31 eligible people with aphasia were enrolled in this trial (recruitment rate = 81 %). All participants but one (23/24) practiced with the language app until the end of hospitalization (retention rate = 96 %). Ten participants practiced at least 30 min/day (adherence rate = 42 %). Participants reported they learned to work quickly with the app (92 %; agreed/totally agreed), the app was easy to use (88 %), they could work independently (79 %), practiced their language (67 %) and wanted to continue working with the app at home (79 %). Acceptability was high (median satisfaction rate 91 %; IQR = 75-100). CONCLUSION: The aphasia exercise program in 'STAPP' is feasible to use as an additional rehabilitation tool along with standard of care in the acute phase post-stroke. Further research is needed to assess the efficacy. CLINICAL TRIAL REGISTRATION-URL: https://clinicaltrials.gov/ct2/show/NCT03679637.

Category specific recall in acute stroke: a case with letter speech.

Category selective recall in spontaneous speech after stroke has been reported only rarely. We recently described three cases demonstrating transient number speech in the acute stage of left hemispheric stroke and hypothesized a link with multilingualism and mathematical proficiency. In this report, we describe a similar case with a transient episode of utterances of randomly selected letters. Like in the three previous cases, this episode was preceded by a brief stage of mutism and ultimately evolved to Wernicke's aphasia over a period of days. This phenomenon is reviewed with reference to linguistic models and neuroanatomic and neurophysiological correlates.

When will a stuttering moment occur? The determining role of speech motor preparation.

The present study aimed to evaluate whether increased activity related to speech motor preparation preceding fluently produced words reflects a successful compensation strategy in stuttering. For this purpose, a contingent negative variation (CNV) was evoked during a picture naming task and measured by use of electro-encephalography. A CNV is a slow, negative event-related potential known to reflect motor preparation generated by the basal ganglia-thalamo-cortical (BGTC) - loop. In a previous analysis, the CNV of 25 adults with developmental stuttering (AWS) was significantly increased, especially over the right hemisphere, compared to the CNV of 35 fluent speakers (FS) when both groups were speaking fluently (Vanhoutte et al., (2015) doi: 10.1016/j.neuropsychologia.2015.05.013). To elucidate whether this increase is a compensation strategy enabling fluent speech in AWS, the present analysis evaluated the CNV of 7 AWS who stuttered during this picture naming task. The CNV preceding AWS stuttered words was statistically compared to the CNV preceding AWS fluent words and FS fluent words. Though no difference emerged between the CNV of the AWS stuttered words and the FS fluent words, a significant reduction was observed when comparing the CNV preceding AWS stuttered words to the CNV preceding AWS fluent words. The latter seems to confirm the compensation hypothesis: the increased CNV prior to AWS fluent words is a successful compensation strategy, especially when it occurs over the right hemisphere. The words are produced fluently because of an enlarged activity during speech motor preparation. The left CNV preceding AWS stuttered words correlated negatively with stuttering frequency and severity suggestive for a link between the left BGTC - network and the stuttering pathology. Overall, speech motor preparatory activity generated by the BGTC - loop seems to have a determining role in stuttering. An important divergence between left and right hemisphere is hypothesized.

The influence of subthalamic nucleus stimulation on pragmatic language production in Parkinson's disease.

While the influence of deep brain stimulation (DBS) of the subthalamic nucleus (STN) on the comprehension of pragmatic language in Parkinson's disease (PD) has been the focus of studies, its impact on production, however, has yet to be elucidated. (1) Investigating the inf luence of DBS STN on pragmatic language production in spontaneous speech by comparing different stimulation conditions and (2) evaluating the effect of asymmetric dopaminergic denervation. This paper included 18 patients with advanced idiopathic PD with STN DBS. [Ten PD patients with predominantly left hemispheric dopamine denervation (PD-left) and eight PD patients with predominantly right-hemispheric dopamine denervation (PD-right).] The pragmatic components 'communicative functions' and 'conversational skills' were evaluated by analysing the spontaneous language production in four stimulation conditions. STN stimulation did not appear to influence the pragmatic production skills. Only when asymmetric dopamine depletion was taken into account the parameter 'giving an explanation' interaction was detectable. STN DBS appears to have some influence on the production of pragmatic language depending on asymmetric dopaminergic denervation. Suggestions are made for further research of pragmatic production in Parkinson's disease.

Subthalamic nucleus stimulation and spontaneous language production in Parkinson's disease: A double laterality problem.

BACKGROUND: Asymmetric degeneration of dopaminergic neurons, are characteristic for Parkinson's disease (PD). Despite the lateralized representation of language, the correlation of asymmetric degeneration of nigrostriatal networks in PD with language performance has scarcely been examined. OBJECTIVE/HYPOTHESIS: The laterality of dopamine depletion influences language deficits in PD and thus modulates the effects of subthalamic nucleus (STN) stimulation on language production. METHODS: The spontaneous language production of patients with predominant dopamine depletion of the left (PD-left) and right (PD-right) hemisphere was compared in four stimulation conditions. RESULTS: PD-right made comparatively more verb inflection errors than PD-left. Bilateral STN stimulation improves spontaneous language production only for PD-left. CONCLUSIONS: The laterality of dopamine depletion influences spontaneous language production and the effect of STN stimulation on linguistic functions. However, it is probably only one of the many variables influencing the effect of STN stimulation on language production.

Increased motor preparation activity during fluent single word production in DS: A correlate for stuttering frequency and severity.

Abnormal speech motor preparation is suggested to be a neural characteristic of stuttering. One of the neurophysiological substrates of motor preparation is the contingent negative variation (CNV). The CNV is an event-related, slow negative potential that occurs between two defined stimuli. Unfortunately, CNV tasks are rarely studied in developmental stuttering (DS). Therefore, the present study aimed to evaluate motor preparation in DS by use of a CNV task. Twenty five adults who stutter (AWS) and 35 fluent speakers (FS) were included. They performed a picture naming task while an electro-encephalogram was recorded. The slope of the CNV was evaluated at frontal, central and parietal electrode sites. In addition, a correlation analysis was performed with stuttering severity and frequency measures. There was a marked increase in CNV slope in AWS as compared to FS. This increase was observed over the entire scalp with respect to stimulus onset, and only over the right hemisphere with respect to lip movement onset. Moreover, strong positive correlations were found between CNV slope and stuttering frequency and severity. As the CNV is known to reflect the activity in the basal ganglia-thalamo-cortical-network, the present findings confirm an increased activation of this loop during speech motor preparation in stuttering. The more a person stutters, the more neurons of this cortical-subcortical network seem to be activated. Because this increased CNV slope was observed during fluent single word production, it is discussed whether or not this observation refers to a successful compensation strategy.

CNV amplitude as a neural correlate for stuttering frequency: A case report of acquired stuttering.

A neural hallmark of developmental stuttering is abnormal articulatory programming. One of the neurophysiological substrates of articulatory preparation is the contingent negative variation (CNV). Unfortunately, CNV tasks are rarely performed in persons who stutter and mainly focus on the effect of task variation rather than on interindividual variation in stutter related variables. However, variations in motor programming seem to be related to variation in stuttering frequency. The current study presents a case report of acquired stuttering following stroke and stroke related surgery in the left superior temporal gyrus. A speech related CNV task was administered at four points in time with differences in stuttering severity and frequency. Unexpectedly, CNV amplitudes at electrode sites approximating bilateral motor and left inferior frontal gyrus appeared to be inversely proportional to stuttering frequency. The higher the stuttering frequency, the lower the activity for articulatory preparation. Thus, the amount of disturbance in motor programming seems to determine stuttering frequency. At right frontal electrodes, a relative increase in CNV amplitude was seen at the test session with most severe stuttering. Right frontal overactivation is cautiously suggested to be a compensation strategy. In conclusion, late CNV amplitude elicited by a relatively simple speech task seems to be able to provide an objective, neural correlate of stuttering frequency. The present case report supports the hypothesis that motor preparation has an important role in stuttering.