Attentional Demand of Motor Speech Encoding: Evidence From Parkinson's Disease.

PURPOSE: While the involvement of attention in utterance planning is well established at the conceptual and lexical levels, the attentional demands of postlexical processes are still debated. This study investigates the involvement of attentional resources on motor speech encoding during utterance production in the context of Parkinson's disease (PD), a population allowing to assess if the attentional demands observed in a dual-task paradigm (the dual-task costs [DTCs]) are explained by postlexical difficulties and not solely by executive impairment. METHOD: Speech production was analyzed in a dual-task paradigm with 30 participants presenting with motor speech disorders due to hypokinetic dysarthria in the context of PD. The dual-task comprised an automatic speech task in which participants recited the days of the week and two nonverbal tasks evaluating processing speed and inhibition. The severity of dysarthria and performance in several executive tests (inhibition, verbal fluency, and cognitive shifting) were used as potential predictors of the DTCs. RESULTS: Individuals with PD exhibited a DTC on the nonverbal tasks and on the speech task when the secondary task was inhibition (the most difficult one). Additionally, the severity of dysarthria and a poorer performance in cognitive shifting predicted a more severe DTC on speech rate. Finally, modulation of the magnitude of the DTCs was observed, depending on the difficulty of the nonverbal secondary task. CONCLUSION: The results suggest that, in PD, postlexical processes require attentional resources and cognitive shifting is related to dual-task performance in speech. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.21265893.

Longitudinal study of speech and dual-task performance in Parkinson's disease patients treated with subthalamic nucleus deep brain stimulation.

INTRODUCTION: Impairments in speech and executive functions are both observed in Parkinson's disease (PD) and might be influenced by subthalamic nucleus deep brain stimulation (STN-DBS). We investigated the effects of STN-DBS on speech and executive functions and their mutual interference in PD. METHODS: 14 PD patients eligible for bilateral STN-DBS (PD-DBS), and 16 PD patients with best medical treatment (PD-BMT) were included. Global cognition, executive functions (inhibition and verbal fluency), speech tasks with acoustic measures, and a dual-task (DT) combining a speech task with a Go or Go/NoGo task were performed at baseline and 12 months follow-up. A normative group of matched healthy participants was included at baseline for the evaluation of speech and DT performance. RESULTS: In both patient groups, global cognition mildly decreased after 12 months (p < .001). PD-DBS showed decreased inhibition (p = .016) whereas PD-BMT deteriorated in vowel articulation (p = .011). Using the DT paradigm, PD-DBS showed a slowing of speech rate after 12 months (p = .009) in contrast to PD-BMT (p = .203). CONCLUSION: STN-DBS does not seem to impair speech and global cognition but might affect certain executive functions (notably inhibition). Speech-cognition interference is relatively preserved in PD patients, even though PD-DBS present larger DT cost on speech rate at 12 months post-DBS compared to PD-BMT. An evaluation with a longer follow-up using a larger sample is needed to confirm long-term effects.

Attention in post-lexical processes of utterance production: Dual-task cost in younger and older adults.

There is a general agreement that speaking requires attention at least for conceptual and lexical processes of utterance production. However, conflicting results have been obtained with dual-task paradigms using either repetition tasks or more generally tasks involving limited loading of lexical selection. This study aimed to investigate whether post-lexical processes recruit attentional resources. We used a new dual-task paradigm in a set of experiments where a continuous verbal production task involved either high or low demand on lexical selection processes. Experiment 1 evaluates lexical and post-lexical processes with a semantic verbal fluency task, whereas Experiments 2 and 3 focus on post-lexical processes with a non-propositional speech task. In each experiment, two types of non-verbal secondary tasks were used: processing speed (simple manual reaction times) or inhibition (Go/No-go). In Experiment 1, a dual-task cost was observed on the semantic verbal fluency task and each non-verbal task. In Experiment 2, a dual-task cost appeared on the non-verbal tasks but not on the speech task. The same paradigm was used with older adults (Experiment 3), as increased effort in post-lexical processes has been associated with ageing. For older adults, a dual-task cost was also observed on the non-propositional verbal task when speech was produced with the inhibition non-verbal task. The results suggest an attentional cost on post-lexical processes and strategic effects in the resolution of the dual-task.

Sensitivity and specificity of an acoustic- and perceptual-based tool for assessing motor speech disorders in French: the MonPaGe-screening protocol.

To respond to the need of objective screening tools for motor speech disorders (MSD), we present the screening version of a speech assessment protocol (MonPaGe-2.0.s), which is based on semi-automated acoustic and perceptual measures on several speech dimensions in French. We validate the screening tool by testing its sensitivity and specificity and comparing its outcome with external standard assessment tools. The data from 80 patients diagnosed with different types of mild to moderate MSD and 62 healthy test controls were assessed against the normative data obtained on 404 neurotypical speakers, with Deviance Scores computed on seven speech dimensions (voice, speech rate, articulation, prosody, pneumophonatory control, diadochokinetic rate, intelligibility) based on acoustic and perceptual measures. A cut-off of the MonPaGe total deviance score (TotDevS) >2 allowed MSD to be diagnosed with specificity of 95% and an overall sensitivity of 83.8% on all patients pulled, reaching 91% when very mildly impaired patients were excluded. A strong correlation was found between the MonPaGe TotDevS and an external composite perceptual score of MSD provided by six experts. The MonPaGe screening protocol has proven its sensitivity and specificity for diagnosing presence and severity of MSD. Further implementations are needed to complement the characterization of impaired dimensions in order to distinguish subtypes of MSD.

Classification of postoperative behavior disturbances in preschool children: A qualitative study.

BACKGROUND/AIM: Negative postoperative changes in children are frequent and have been described for decades. However, there is currently no theoretical framework, nor any consensual operational criteria for identifying them. This study aims at characterizing the many dimensions involved in postoperative behavioral disturbances in early childhood, using a qualitative analysis applied for the first time to these symptoms. METHOD: Fifty-seven parents of preschool children (1-5 years old; 38 boys), who underwent general anesthesia, were interviewed 10 days after surgery. Semi-structured interviews investigated behavioral disturbances classically described in preschool children. Qualitative analysis of the transcripts allied both deductive and inductive reasoning, and inductive coding was carried out using constant comparison method with dedicated qualitative software. RESULTS: Parents reported both positive and negative postoperative changes. Negative changes were classified in four main categories: (a) Externalizing and (b) Internalizing problems behaviors, (c) Feeding sleeping disruption and (d) Somatic problems, each comprising different sub-categories. Importantly within these categories, the symptoms distribution changed in 5 years old children, compared to younger children. Finally, our method allowed defining whether these (negative or positive) changes were significant or not, that is, the importance of postoperative behavioral changes. CONCLUSION: The results of this study highlight the heterogeneity of postoperative disturbances in preschool children. These results are of primary importance for the definition and measurement of postoperative behavioral disturbances.

Neuropsychological outcome after extra-temporal epilepsy surgery.

BACKGROUND: The neuropsychological results of temporal lobe epilepsy surgery are well reported in the literature. The aim of this study was to analyse the neuropsychological outcome in a consecutive series of patients with extra-temporal epilepsy. METHODS: We retrospectively analysed the data of patients operated between 1996 and 2008 for extra-temporal epilepsy. Standard neuropsychological tests were applied. We assessed the neuropsychological outcome after surgery and the correlation of the neuropsychological outcome with (1) side and localisation of surgery, (2) Engel scale for seizure outcome and (3) timing of surgery. FINDINGS: Patients had a better neuropsychological outcome when undergoing non-frontal resection [χ2 (2) =6.66, p = 0.036]. Subjects who had undergone left or right resection showed no difference in outcome [χ2 (2) =0.533, p = 0.766]. The correlation between the Engel scale for seizure re-occurence and the neuropsychological scores showed only a tendency for better outcome (Spearman ρ = -0.437; p = 0.069). The global measure of change did not correlate significantly with delay of surgery (Spearman ρ = -0.163; p = 0.518). CONCLUSIONS: Resective epilepsy surgery improves neuropsychological status outcome in patients with extra-temporal epilepsy even if the patient did not become seizure free. The outcome is better for non-frontal localisation.