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1.
J Mot Behav ; 55(3): 313-329, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36919517

RESUMO

Motor evoked potential amplitude (MEPamp) is frequently measured in transcranial direct current stimulation (tDCS) studies that target the primary motor cortex (M1), and a subset of these studies involve motor behavior. This systematic review explored the role of MEPamp as an indicator of neural change in M1-targeted tDCS studies involving motor behavior (i.e., motor practice and/or evaluation of motor performance) in healthy individuals, and examined the association between changes in motor performance and MEPamp. We executed our search strategy across four bibliographic databases. Twenty-two manuscripts met eligibility criteria. While anodal tDCS combined with motor practice frequently increased MEPamp, MEPamp outcomes did not necessarily align with changes in motor performance. Thus, MEPamp may not be the most appropriate indicator of neural change in tDCS studies that aim to improve motor performance.


Assuntos
Córtex Motor , Estimulação Transcraniana por Corrente Contínua , Humanos , Potencial Evocado Motor/fisiologia , Córtex Motor/fisiologia , Estimulação Magnética Transcraniana
2.
Phys Occup Ther Pediatr ; 43(4): 463-481, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36624962

RESUMO

PURPOSE: Describe how transcranial direct current stimulation (tDCS) was incorporated into an inpatient physiotherapy program for an adolescent with severe traumatic brain injury (TBI), detail the motor learning focus of the physiotherapy sessions, and summarize gross motor progress. METHOD: This case report describes an adolescent who received 20 minutes of anodal tDCS immediately prior to 16 physiotherapy sessions over four weeks. Potential side effects were tracked pre/post tDCS. Gross motor outcomes were measured pre-intervention, post-intervention, and three months post-intervention. Physiotherapy session content was analyzed using therapist documentation and the Motor Learning Strategies Rating Instrument. RESULTS: The youth tolerated tDCS well. The primary side effect was itchiness under the electrodes during tDCS sessions. His mobility progressed from wheelchair use pre- 'tDCS + physiotherapy' to ambulation with a walker post-intervention. His Gross Motor Function Measure score increased 33.1% points pre/post intervention. Session tasks often had several foci (e.g., skill acquisition, strength, and balance) with task focus changing as the youth progressed. Various motor learning strategies were layered within tasks to support performance and learning. CONCLUSIONS: tDCS was successfully integrated into an existing inpatient physiotherapy program for an adolescent with TBI. This protocol provides a structure for implementing, monitoring, and measuring tDCS + physiotherapy in pediatric rehabilitation.


Assuntos
Lesões Encefálicas Traumáticas , Córtex Motor , Estimulação Transcraniana por Corrente Contínua , Criança , Humanos , Adolescente , Estimulação Transcraniana por Corrente Contínua/métodos , Pacientes Internados , Córtex Motor/fisiologia , Aprendizagem/fisiologia , Lesões Encefálicas Traumáticas/terapia
3.
Dysphagia ; 38(1): 278-289, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35701690

RESUMO

Bedside dysphagia assessment protocols are not well developed in acute pediatric stroke unlike adults. The objective of this study was to identify items deemed relevant and feasible by expert consensus to inform the development of a bedside dysphagia screening tool for acute pediatric stroke. A two-phase study was conducted: (1) literature review and expert consultation generated a comprehensive list of dysphagia assessment items; (2) items were formatted in an online survey asking respondents opinion of relevance to acute pediatric stroke and feasibility for bedside administration by a trained health professional. The Dillman Tailored Design approach optimized response rate. Respondents were identified using the snowball method. Speech-language pathologists with > 2 years in pediatric dysphagia were invited to complete the survey. Demographic and practice variables were compared using univariate statistics. Item relevance and feasibility were made using binary or ordinal responses, combined to derive item-content validity indices (I-CVI) to guide item reduction. Items with I-CVI > 0.78 (excellent content validity) were moved forward to tool development. Of the 71 invited respondents, 57(80.3%) responded, of which 34(59.6%) were from North America. Sixty-one items were generated of which 4(6.6%) items were rated 'to keep'. These were face symmetry (I-CVI:0.89), salivary control (I-CVI:0.95), alertness (I-CVI:0.89) and choking (I-CVI:0.84). Of all respondents, 31(54.4%) endorsed swallowing trials, of which 25(80.6%) endorsed thin liquid by teaspoon (n = 17, 68%) or open cup (n = 20, 80%). We identified candidate items for bedside dysphagia screening with excellent content validity for acute pediatric stroke patients. Next steps include assessment of the psychometric value of each item in identifying dysphagia in children in the acute stage of recovery from stroke.


Assuntos
Transtornos de Deglutição , Acidente Vascular Cerebral , Adulto , Humanos , Criança , Transtornos de Deglutição/diagnóstico , Transtornos de Deglutição/etiologia , Deglutição , Acidente Vascular Cerebral/complicações , Programas de Rastreamento/métodos , Psicometria , Reprodutibilidade dos Testes
4.
Dev Med Child Neurol ; 65(7): 953-960, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36404436

RESUMO

AIM: To estimate gross motor change in inpatient school-aged children with subacute acquired brain injury (ABI), identify factors associated with gross motor change, and describe inpatient physiotherapy focus. METHOD: This retrospective chart review involved inpatient children (5-18 years) with subacute ABI who had either two Gross Motor Function Measure (GMFM-88) assessments or one GMFM-88 with another pre/post gross motor outcome measure. Outcome change scores and Goal Attainment Scaling (GAS) T scores were calculated. Regression analyses examined factors predicting gross motor change. GAS goal areas were analysed to determine physiotherapy focus. RESULTS: Of the 546 charts screened, 266 (118 female) met study criteria. The GMFM-88 was generally administered first, followed by other measures. GMFM-88 (n = 202), Community Balance and Mobility Scale (n = 89), and Six-Minute Walk Test (6MWT) (n = 98) mean change scores were 18.03% (SD 19.34), 17.85% (SD 10.77), and 142.3 m (SD 101.8) respectively. The mean GAS T score was 55.06 (SD 11.50). Lower baseline scores and increased time between assessments were most predictive of greater GMFM-88 change (r ≥ 0.40). Twenty-five percent of GAS goals were ambulation-based. INTERPRETATION: Appropriate outcome measure selection is integral to detecting gross motor change in pediatric inpatient ABI rehabilitation. Mean change score estimates can be used to compare standard inpatient rehabilitation with new treatment approaches.


Assuntos
Lesões Encefálicas , Paralisia Cerebral , Criança , Humanos , Feminino , Estudos Retrospectivos , Pacientes Internados , Avaliação da Deficiência , Destreza Motora
5.
Front Hum Neurosci ; 16: 858863, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35664350

RESUMO

Purpose: The ability to hear ourselves speak has been shown to play an important role in the development and maintenance of fluent and coherent speech. Despite this, little is known about the developing speech motor control system throughout childhood, in particular if and how vocal and articulatory control may differ throughout development. A scoping review was undertaken to identify and describe the full range of studies investigating responses to frequency altered auditory feedback in pediatric populations and their contributions to our understanding of the development of auditory feedback control and sensorimotor learning in childhood and adolescence. Method: Relevant studies were identified through a comprehensive search strategy of six academic databases for studies that included (a) real-time perturbation of frequency in auditory input, (b) an analysis of immediate effects on speech, and (c) participants aged 18 years or younger. Results: Twenty-three articles met inclusion criteria. Across studies, there was a wide variety of designs, outcomes and measures used. Manipulations included fundamental frequency (9 studies), formant frequency (12), frequency centroid of fricatives (1), and both fundamental and formant frequencies (1). Study designs included contrasts across childhood, between children and adults, and between typical, pediatric clinical and adult populations. Measures primarily explored acoustic properties of speech responses (latency, magnitude, and variability). Some studies additionally examined the association of these acoustic responses with clinical measures (e.g., stuttering severity and reading ability), and neural measures using electrophysiology and magnetic resonance imaging. Conclusion: Findings indicated that children above 4 years generally compensated in the opposite direction of the manipulation, however, in several cases not as effectively as adults. Overall, results varied greatly due to the broad range of manipulations and designs used, making generalization challenging. Differences found between age groups in the features of the compensatory vocal responses, latency of responses, vocal variability and perceptual abilities, suggest that maturational changes may be occurring in the speech motor control system, affecting the extent to which auditory feedback is used to modify internal sensorimotor representations. Varied findings suggest vocal control develops prior to articulatory control. Future studies with multiple outcome measures, manipulations, and more expansive age ranges are needed to elucidate findings.

6.
J Head Trauma Rehabil ; 37(5): 293-302, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35125430

RESUMO

OBJECTIVE: To examine child behavior change scores from randomized controlled trials (RCTs) of parent interventions for pediatric traumatic brain injury (TBI). METHODS: MEDLINE, EMBASE, PsycINFO, and CINAHL were searched to identify studies that examined parent interventions for pediatric TBI. Inclusion criteria included (i) a parent intervention for children with TBI; (ii) an RCT study design; (iii) statistical data for child behavior outcome(s); and (iv) studies that were published in English. RESULTS: Seven studies met inclusion criteria. All interventions reported improved child behavior after pediatric TBI; however, child and parent factors contributed to behavior change scores in some interventions. Factors found to contribute to the level of benefit included age of child, baseline behavior levels, sociodemographics (eg, parent income, parent education), and parent mental health. CONCLUSION: Improved child behavior outcomes resulting from parent interventions for pediatric TBI are well supported by the evidence in the peer-reviewed literature. Clinicians are encouraged to consider child and parent factors as they relate to child behavior outcomes.


Assuntos
Lesões Encefálicas Traumáticas , Pais , Criança , Humanos , Pais/psicologia
7.
Brain Inj ; 36(1): 39-51, 2022 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-35157529

RESUMO

OBJECTIVE: Explore the feasibility, tolerability, and early efficacy of transcranial direct current stimulation (tDCS) as a therapeutic intervention for youth with cognitive persistent post-concussion symptoms (PPCS). HYPOTHESIS: tDCS improves performance on a dual task working memory (WM) paradigm in youth with cognitive PPCS. PARTICIPANTS: Twelve youth experiencing cognitive PPCS. DESIGN: A quasi-randomized pilot trial was used to explore the tolerability of, and performance differences on, a dual N-Back WM task paired with active or sham tDCS over 3 sessions. MEASURES: Accuracy and reaction time on WM task and self-report of tDCS tolerability. RESULTS: Trends toward increases in accuracy from Day 1 to 3 seen in both groups. Active tDCS group performed better than sham on Day 2 in N-Back level N2 (p = .019), and marginally better than the sham group on Day 3 in level N3 (p = .26). Participants reported tDCS as tolerable; compared to the active tDCS group, the sham group reported more "considerable" (p = .078) and "strong" symptoms (p = .097). CONCLUSION: tDCS is a promising tool for enhancing WM performance and is a feasible and tolerable adjunct to behavioral interventions in youth with cognitive PPCS. A clinical trial to demonstrate efficacy is warranted.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Adolescente , Cognição , Método Duplo-Cego , Humanos , Memória de Curto Prazo/fisiologia , Projetos Piloto , Córtex Pré-Frontal/fisiologia , Tempo de Reação
8.
Eur J Appl Physiol ; 122(4): 965-974, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35084541

RESUMO

PURPOSE: To contrast older and younger adults' prefrontal cortex (PFC) neural activity (through changes in oxygenated hemoglobin) during single and dual tasks, and to compare decrements in task performance. METHODS: Changes in oxygenated hemoglobin of dorsolateral PFC were monitored using functional near-infrared spectroscopy during single tasks of spelling backwards (cognitive task) and 30 m preferred paced walk; and a dual task combining both. Gait velocity was measured by a pressure sensitive mat. RESULTS: Twenty sex-matched younger (27.6 ± 3.5 years) and 17 older adults (71.2 ± 4.9 years) were recruited. The left PFC oxygenated hemoglobin decreased from start (1st quintile) to the end (5th quintile) of the walking task in younger adults ( - 0.03 ± 0.03 to - 0.72 ± 0.20 µM; p < .05) unlike the non-significant change in older adults (0.03 ± 0.06 to - 0.41 ± 0.32 µM, p > .05). Overall, oxygenation increased bilaterally during dual versus single walk task in older adults (Left PFC: 0.22 ± 0.16 vs. - 0.23 ± 0.21 µM, respectively; Right PFC: 0.17 ± 0.18 vs. - 0.33 ± 0.22 µM, respectively), but only in right PFC in younger adults ( - 0.02 ± 0.15 vs. - 0.47 ± 0.13 µM). Older adults exhibited lower velocity during the dual task compared to younger adults (1.03 ± 0.16 vs. 1.20 ± 0.17 m/s, respectively). Older age was associated with dual task cost on velocity during walking after adjusting for confounding variables. CONCLUSIONS: Age-related cognitive decline in older adults may increase neural activity for cognitive tasks and diminish walking automaticity that may lead to decrements during dual tasking; the greater PFC increases in the oxygenated hemoglobin and lower velocity may be due to increased cognitive load and limited attentional resources.


Assuntos
Cognição , Espectroscopia de Luz Próxima ao Infravermelho , Idoso , Marcha , Humanos , Oxiemoglobinas , Caminhada
9.
J Autism Dev Disord ; 52(2): 725-737, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33765302

RESUMO

Examining brain and behaviour associations for language in autism spectrum disorder (ASD) may bring us closer to identifying neural profiles that are unique to a subgroup of individuals with ASD identified as language impaired (e.g. ASD LI+). We conducted a scoping review to examine brain regions that are associated with language performance in ASD. Further, we examined methodological differences across studies in how language ability was characterized and what neuroimaging methods were used to explore brain regions. Seventeen studies met inclusion criteria. Brain regions specific to ASD LI+ groups were found, however inconsistencies in brain and language associations were evident across study findings. Participant age, age-appropriate language scores, and neuroimaging methods likely contributed to differences in associations found.


Assuntos
Transtorno do Espectro Autista , Transtorno do Espectro Autista/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Humanos , Idioma , Neuroimagem
10.
J Int Neuropsychol Soc ; 28(10): 1091-1103, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34823632

RESUMO

OBJECTIVES: To examine the effects of pediatric traumatic brain injury (TBI) on verbal IQ by severity and over time. METHODS: A systematic review and subsequent meta-analysis of verbal IQ by TBI severity were conducted using a random effects model. Subgroup analysis included two epochs of time (e.g., <12 months postinjury and ≥12 months postinjury). RESULTS: Nineteen articles met inclusion criteria after an extensive literature search in MEDLINE, PsycInfo, Embase, and CINAHL. Meta-analysis revealed negative effects of injury across severities for verbal IQ and at both time epochs except for mild TBI < 12 months postinjury. Statistical heterogeneity (i.e., between-study variability) stemmed from studies with inconsistent classification of mild TBI, small sample sizes, and in studies of mixed TBI severities, although not significant. Risk of bias on estimated effects was generally low (k = 15) except for studies with confounding bias (e.g., lack of group matching by socio-demographics; k = 2) and measurement bias (e.g., outdated measure at time of original study, translated measure; k = 2). CONCLUSIONS: Children with TBI demonstrate long-term impairment in verbal IQ, regardless of severity. Future studies are encouraged to include scores from subtests within verbal IQ (e.g., vocabulary, similarities, comprehension) in addition to functional language measures (e.g., narrative discourse, reading comprehension, verbal reasoning) to elucidate higher-level language difficulties experienced in this population.


Assuntos
Lesões Encefálicas Traumáticas , Transtornos da Comunicação , Criança , Humanos , Lesões Encefálicas Traumáticas/complicações , Resolução de Problemas , Leitura , Compreensão
11.
J Acoust Soc Am ; 150(4): 2647, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34717445

RESUMO

Auditory feedback is an important component of speech motor control, but its precise role in developing speech is less understood. The role of auditory feedback in development was probed by perturbing the speech of children 4-9 years old. The vowel sound /ɛ/ was shifted to /æ/ in real time and presented to participants as their own auditory feedback. Analyses of the resultant formant magnitude changes in the participants' speech indicated that children compensated and adapted by adjusting their formants to oppose the perturbation. Older and younger children responded to perturbation differently in F1 and F2. The compensatory change in F1 was greater for younger children, whereas the increase in F2 was greater for older children. Adaptation aftereffects were observed in both groups. Exploratory directional analyses in the two-dimensional formant space indicated that older children responded more directly and less variably to the perturbation than younger children, shifting their vowels back toward the vowel sound /ɛ/ to oppose the perturbation. Findings support the hypothesis that auditory feedback integration continues to develop between the ages of 4 and 9 years old such that the differences in the adaptive and compensatory responses arise between younger and older children despite receiving the same auditory feedback perturbation.


Assuntos
Percepção da Fala , Adaptação Fisiológica , Adolescente , Criança , Pré-Escolar , Retroalimentação Sensorial , Humanos , Fonética , Fala , Acústica da Fala , Medida da Produção da Fala
12.
Brain Inj ; 35(10): 1275-1283, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34499576

RESUMO

OBJECTIVE: Establish objective and subjective speech rate and muscle function differences between athletes with and without sports related concussion (SRC) histories and provide potential motor speech evaluation in SRC. METHODS: Over 1,110 speech samples were obtained from 30, 19-22 year-old athletes who had sustained an SRC within the past 2 years and 30 pair-wise matched control athletes with no history of SRC. Speech rate was measured via average time per syllable, average unvoiced time per syllable, and expert perceptual judgment. Speech muscle function was measured via surface electromyography over the obicularis oris, masseter, and segmental triangle. Group differences were assessed using MANOVA, bootstrapping and predictive ROC analyses. RESULTS: Athletes with SRC had slower speech rates during DDK tasks than controls as evidenced by longer average time per syllable longer average unvoiced time per syllable and expert judgment of slowed rate. Rate measures were predictive of concussion history. Further, athletes with SRC required more speech muscle activation than controls to complete DDK tasks. CONCLUSION: Clear evidence of slowed speech and increased muscle activation during the completion of DDK tasks in athletes with SRC histories relative to controls. Future work should examine speech rate in acute concussion.


Assuntos
Traumatismos em Atletas , Concussão Encefálica , Esportes , Adulto , Atletas , Traumatismos em Atletas/complicações , Concussão Encefálica/complicações , Humanos , Músculos , Fala , Adulto Jovem
13.
Exp Brain Res ; 239(11): 3303-3313, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34476535

RESUMO

Neurophysiological experiments using transcranial magnetic stimulation (TMS) have sought to probe the function of the motor division of the corpus callosum. Primary motor cortex sends projections via the corpus callosum with a net inhibitory influence on the homologous region of the opposite hemisphere. Interhemispheric inhibition (IHI) experiments probe this inhibitory pathway. A test stimulus (TS) delivered to the motor cortex in one hemisphere elicits motor evoked potentials (MEPs) in a target muscle, while a conditioning stimulus (CS) applied to the homologous region of the opposite hemisphere modulates the effect of the TS. We predicted that large CS MEPs would be associated with increased IHI since they should be a reliable index of how effectively contralateral motor cortex was stimulated and therefore of the magnitude of interhemispheric inhibition. However, we observed a strong tendency for larger CS MEPs to be associated with reduced interhemispheric inhibition which in the extreme lead to a net effect of facilitation. This surprising effect was large, systematic, and observed in nearly all participants. We outline several hypotheses for mechanisms which may underlie this phenomenon to guide future research.


Assuntos
Córtex Motor , Inibição Neural , Corpo Caloso , Potencial Evocado Motor , Humanos , Estimulação Magnética Transcraniana
14.
Brain Inj ; 35(10): 1121-1133, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34506212

RESUMO

Objective: Characterize the working memory (WM) profile of children and youth who have experienced concussion by systematically synthesizing existing literature on the neuropsychological outcomes of these injuries.Methods: Implemented a peer-reviewed search strategy combining key concepts of concussion/mild traumatic brain injury (mTBI), WM, and pediatrics across MedLine, Embase, PsycINFO, and CINAHL. Included studies written in English with extractable results on a WM outcome measure in individuals aged 21 and under who experienced concussion. Applied narrative synthesis to identify trends in the literature. Assessed risk of bias and quality using the NHLBI's Quality Assessment of Observational Cohort and Cross-Sectional Studies.Results: 40 articles met inclusion criteria. 34/40 studies compared WM performance in children or youth with concussion to healthy controls, pre-injury performance, or normative values, of which 15 reported significantly lower WM performance in the concussion sample. Visual/spatial WM was more consistently impacted than verbal WM. Cognitive demanding dual-task conditions were also reliably impacted.Conclusion: Literature indicated that WM is vulnerable to negative outcomes following pediatric concussion, yet the nature of outcomes is variable. Clinicians and researchers should implement comprehensive and theoretically motivated WM assessments to better understand the WM components impacted by injury.


Assuntos
Concussão Encefálica , Pediatria , Adolescente , Concussão Encefálica/complicações , Criança , Cognição , Estudos Transversais , Humanos , Memória de Curto Prazo
15.
J Pediatr Rehabil Med ; 14(3): 389-399, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34511517

RESUMO

PURPOSE: To examine language outcomes in the short-term stage (i.e., within three months) of early childhood traumatic brain injury (TBI). METHODS: A retrospective chart review over a 10-year period (January 1, 2007 to December 31, 2016) was completed at a single-site inpatient rehabilitation hospital. Inclusion criteria were children aged 15 months to five years 11 months with a diagnosis of closed TBI. RESULTS: Twenty-four charts were included in the descriptive analysis of language; there were fewer children with expressive language scores (n = 18) than receptive language scores (n = 24), likely due to word retrieval difficulties as per clinical documentation. Effects of TBI on language performance were more pronounced in receptive than expressive language. For children with scores in both receptive and expressive language areas (n = 18), five children had below average scores. These children were described as having language delays pre-injury (n = 2), lower exposure to English (n = 1), information processing difficulties (n = 1), and difficulties with formulation and organization of language (n = 1). CONCLUSION: This study represents an initial step in understanding expressive and receptive language performance shortly after early childhood TBI. Challenges with assessment as well as directions for future research are discussed.


Assuntos
Lesões Encefálicas Traumáticas , Idioma , Lesões Encefálicas Traumáticas/complicações , Pré-Escolar , Cognição , Humanos , Estudos Retrospectivos
16.
J Clin Neurosci ; 91: 32-42, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34373047

RESUMO

Few studies have investigated the neural mechanisms underlying speech production in children who stutter (CWS), despite the critical importance of understanding these mechanisms closer to the time of stuttering onset. The relative contributions of speech planning and execution in CWS therefore are also unknown. Using functional near-infrared spectroscopy, the current study investigated neural mechanisms of planning and execution in a small sample of 9-12 year-old CWS and controls (N = 12) by implementing two tasks that manipulated speech planning and execution loads. Planning was associated with atypical activation in bilateral inferior frontal gyrus and right supramarginal gyrus. Execution was associated with atypical activation in bilateral precentral gyrus and inferior frontal gyrus, as well as right supramarginal gyrus and superior temporal gyrus. The CWS exhibited some activation patterns that were similar to the adults who stutter (AWS) as reported in our previous study: atypical planning in frontal areas including left inferior frontal gyrus and atypical execution in fronto-temporo-parietal regions including left precentral gyrus, and right inferior frontal, superior temporal, and supramarginal gyri. However, differences also emerged. Whereas CWS and AWS both appear to exhibit atypical activation in right inferior and supramarginal gyri during execution, only CWS appear to exhibit this same pattern during planning. In addition, the CWS appear to exhibit atypical activation in left inferior frontal and right precentral gyri related to execution, whereas AWS do not. These preliminary results are discussed in the context of possible impairments in sensorimotor integration and inhibitory control for CWS.


Assuntos
Fala , Gagueira , Encéfalo/diagnóstico por imagem , Criança , Humanos , Imageamento por Ressonância Magnética , Espectroscopia de Luz Próxima ao Infravermelho , Gagueira/diagnóstico por imagem
17.
Neurobiol Lang (Camb) ; 2(1): 106-137, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34296194

RESUMO

Stuttering is a neurodevelopmental disorder characterized by impaired production of coordinated articulatory movements needed for fluent speech. It is currently unknown whether these abnormal production characteristics reflect disruptions to brain mechanisms underlying the acquisition and/or execution of speech motor sequences. To dissociate learning and control processes, we used a motor sequence learning paradigm to examine the behavioral and neural correlates of learning to produce novel phoneme sequences in adults who stutter (AWS) and neurotypical controls. Participants intensively practiced producing pseudowords containing non-native consonant clusters (e.g., "gvasf") over two days. The behavioral results indicated that although the two experimental groups showed comparable learning trajectories, AWS performed significantly worse on the task prior to and after speech motor practice. Using functional magnetic resonance imaging (fMRI), the authors compared brain activity during articulation of the practiced words and a set of novel pseudowords (matched in phonetic complexity). FMRI analyses revealed no differences between AWS and controls in cortical or subcortical regions; both groups showed comparable increases in activation in left-lateralized brain areas implicated in phonological working memory and speech motor planning during production of the novel sequences compared to the practiced sequences. Moreover, activation in left-lateralized basal ganglia sites was negatively correlated with in-scanner mean disfluency in AWS. Collectively, these findings demonstrate that AWS exhibit no deficit in constructing new speech motor sequences but do show impaired execution of these sequences before and after they have been acquired and consolidated.

18.
Neuroimage ; 239: 118326, 2021 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-34216772

RESUMO

Vocal flexibility is a hallmark of the human species, most particularly the capacity to speak and sing. This ability is supported in part by the evolution of a direct neural pathway linking the motor cortex to the brainstem nucleus that controls the larynx the primary sound source for communication. Early brain imaging studies demonstrated that larynx motor cortex at the dorsal end of the orofacial division of motor cortex (dLMC) integrated laryngeal and respiratory control, thereby coordinating two major muscular systems that are necessary for vocalization. Neurosurgical studies have since demonstrated the existence of a second larynx motor area at the ventral extent of the orofacial motor division (vLMC) of motor cortex. The vLMC has been presumed to be less relevant to speech motor control, but its functional role remains unknown. We employed a novel ultra-high field (7T) magnetic resonance imaging paradigm that combined singing and whistling simple melodies to localise the larynx motor cortices and test their involvement in respiratory motor control. Surprisingly, whistling activated both 'larynx areas' more strongly than singing despite the reduced involvement of the larynx during whistling. We provide further evidence for the existence of two larynx motor areas in the human brain, and the first evidence that laryngeal-respiratory integration is a shared property of both larynx motor areas. We outline explicit predictions about the descending motor pathways that give these cortical areas access to both the laryngeal and respiratory systems and discuss the implications for the evolution of speech.


Assuntos
Laringe/fisiologia , Imageamento por Ressonância Magnética/métodos , Córtex Motor/fisiologia , Vias Neurais/fisiologia , Respiração , Fala/fisiologia , Adulto , Feminino , Humanos , Análise dos Mínimos Quadrados , Masculino , Córtex Motor/diagnóstico por imagem , Mecânica Respiratória/fisiologia , Descanso/fisiologia , Canto/fisiologia , Adulto Jovem
19.
Stroke ; 52(4): 1309-1318, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33641384

RESUMO

BACKGROUND AND PURPOSE: Following adult stroke, dysphagia, dysarthria, and aphasia are common sequelae. Little is known about these impairments in pediatric stroke. We assessed frequencies, co-occurrence and associations of dysphagia, oral motor, motor speech, language impairment, and caregiver burden in pediatric stroke. METHODS: Consecutive acute patients from term birth-18 years, hospitalized for arterial ischemic stroke (AIS), and cerebral sinovenous thrombosis, from January 2013 to November 2018 were included. Two raters reviewed patient charts to detect documentation of in-hospital dysphagia, oral motor dysfunction, motor speech and language impairment, and caregiver burden, using a priori operational definitions for notation and assessment findings. Other variables abstracted included demographics, preexisting conditions, stroke characteristics, and discharge disposition. Impairment frequencies were obtained by univariate and bivariate analysis and associations by simple logistic regression. RESULTS: A total of 173 patients were stratified into neonates (N=67, mean age 2.9 days, 54 AIS, 15 cerebral sinovenous thrombosis) and children (N=106, mean age 6.5 years, 73 AIS, 35 cerebral sinovenous thrombosis). Derived frequencies of impairments included dysphagia (39% neonates, 41% children); oral motor (6% neonates, 41% children); motor speech (37% children); and language (31% children). Common overlapping impairments included oral motor and motor speech (24%) and dysphagia and motor speech (23%) in children. Associations were found only in children between stroke type (AIS over cerebral sinovenous thrombosis) and AIS severity (more severe deficit at presentation) for all impairments except feeding impairment alone. Caregiver burden was present in 58% patients. CONCLUSIONS: For the first time, we systematically report the frequencies and associations of dysphagia, oral motor, motor speech, and language impairment during acute presentation of pediatric stroke, ranging from 30% to 40% for each impairment. Further research is needed to determine long-term effects of these impairments and to design standardized age-specific assessment protocols for early recognition following stroke.


Assuntos
Afasia/etiologia , Sobrecarga do Cuidador , Transtornos de Deglutição/etiologia , Disartria/etiologia , AVC Isquêmico/complicações , Adulto , Afasia/epidemiologia , Criança , Pré-Escolar , Transtornos de Deglutição/epidemiologia , Disartria/epidemiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos
20.
Neuropsychol Rev ; 31(1): 1-13, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33398784

RESUMO

Verbal fluency is a neuropsychological measure commonly used to examine cognitive-linguistic performance as reported in pediatric TBI literature. We synthesized the scholarly literature of verbal fluency performance in pediatric TBI and estimated the effects of TBI according to: (i) type of verbal fluency task (phonemic or semantic), (ii) severity of TBI, and (iii) time post-injury. Meta-analysis revealed that childhood TBI negatively impacted phonemic fluency and semantic fluency and that effect sizes were larger for children with more severe TBI. The negative effect of TBI was evident across time post injury within each level of severity. Verbal fluency tasks are efficient indicators of potential underlying impairments in lexical knowledge and executive functioning in children with TBI regardless of severity of injury or time post injury. Future research employing verbal fluency tasks are encouraged to explore if age at injury differentiates semantic versus phonemic fluency outcomes across severity levels.


Assuntos
Lesões Encefálicas Traumáticas , Comportamento Verbal , Lesões Encefálicas Traumáticas/complicações , Criança , Função Executiva , Humanos , Testes Neuropsicológicos , Semântica
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