Motor Difficulties Research Articles

Assessment of control during movement, fine motor skills/handwriting, and gross motor control in children with developmental coordination disorder using the DCD-Q

Motor coordination and control are affected by Developmental Coordination Disorder (DCD), particularly in children. As a result, they are unable to write, tie shoelaces, or participate in sports, affecting their social interactions and quality of life. Considering the poor short-term and long-term outcomes observed in children with DCD, awareness of this condition may increase, prompting more research. Among 99 children with DCD, a six-week intervention was performed in both control and intervention groups. In addition to the DCD-Q questionnaire, parents completed a fine motor/handwriting and gross motor control questionnaire. An ANOVA test was used to analyze all values as mean ± SD. The results showed that both groups improved in motor coordination and control. DCD-related motor difficulties can be addressed more effectively with early intervention in all three domains, especially fine motor control. The control group’s motor control scores increased from 17.9 ± 0.6 at baseline to 21.5 ± 0.5 by the sixth week, with a statistically significant p-value of 0.009. Alternatively, the intervention group’s scores improved from 19.6 ± 0.5 at baseline to 22.4 ± 0.5 at the sixth week, with a statistically significant p-value of 0.007. With regards to fine motor control, the control group’s scores improved from 13.4 ± 1.08 at baseline to 16.4 ± 0.6 at the sixth week, with a statistically significant p-value of 0.01. With regards to fine motor control, the intervention group’s scores improved from 14.5 ± 0.3 at baseline to 20.3 ± 1.4 at the sixth week, with a statistically significant p-value of 0.004. As for gross motor control, the control group’s score increased from 16.6 ± 1.05 at baseline to 20.2 ± 1.0 at the sixth week, showing high statistical significance with a p-value of <0.0001. The intervention group’s scores improved from 18.7 ± 0.5 at baseline to 21.5 ± 0.7 at the sixth week, also demonstrating statistical significance with a p-value of 0.002. Overall, this study highlights the potential benefits of tailored interventions in enhancing motor skills and overall quality of life for children with DCD.

Angelman syndrome: A genetic challenge for physical and learning disabilities

Angelman syndrome (AS) was first reported in 1965 by Dr. Harry Angelman. It is a condition of neurodevelopment characterized by, a lack of speech, distinctive behavior, seizure, intellectual capacity, and cheerful disposition. The cause of AS is a lack of production by maternal imprinted genes (UBE3A) on the 15q11-q13 chromosome. The complications of AS are strabismus, atrophy of the optical nerve, and blindness, which are rarely reported. There is a possibility of complications in the laboratory diagnostic tests for AS. One method is to evaluate with DNA methylation analysis of AS/Prader-Willi Syndrome (PWS) imprinting center (IC). On cytogenetic analysis, at least 50–60% of patients had a maternally induced de novo mutation of chromosome 15q11-13 with more serious clinical phenotypes such as microcephaly, seizures, language impairment, and motor difficulties. Multiexonic or whole gene deletion is identified by array-comparative genomic hybridisation (CGH) in some cases and laboratory and methodology may vary such deletions. Diagnosis of AS can be suggested by unsteady movements before walking. Based on the patient’s medical history, electroencephalogram (EEG) data, clinical symptoms, and the presence or absence of a chromosome 50 deletion, a diagnosis of AS is made. Incidence estimated for AS is approximately 1 in 12,000–20,000 birth lives, but the epidemiological measures of life expectancy remains unknown. The clinical features of AS phenotype include seizures, sleep disturbance, intellectual disability, and movement disorders such as tremor and ataxia, anxiety, expressive language is limited, behavioral changes, pleasant demeanor, and easily manipulated laughs, EEG abnormalities were discovered in around 100% of the patients. The researcher identified problems with inflammation at the injection site caused by a higher dose of a drug and they monitored proteins in the individual’s blood and cerebrospinal fluid as an additional safety precaution. Genetic counseling for families with one child with AS to address the likelihood of recurrence can be a challenging subject that frequently requires specialist advice.

Feasibility of an eye-gaze technology intervention for students with severe motor and communication difficulties in Taiwan

Eye-gaze technology provides access to a computer through the control of eye movements, thus allowing students with severe motor and communication difficulties to communicate and participate in curriculum activities and leisure; however, few studies have investigated whether any challenges exist to its implementation. This study examines the feasibility for teachers, parents, and therapists of applying an eye-gaze technology intervention for students with severe motor and communication difficulties in everyday settings. A mixed-method design was applied, focusing on the acceptability, demands, implementation, and practicality of the technology applications. Data was collected from 16 participants who assisted five students using eye-gaze technology in a previous 6-month intervention. The intervention comprised (a) use of eye-gaze devices with individualized content; and (b) services including training in use, team meetings, and bi-monthly support on implementation problems. The results showed that the participants perceived the technology as appropriate to enhance interaction and understanding of the students’ learning and communication messages. Portable and easy-to-adjust systems were crucial to apply eye-gaze technology in different contexts. Improving eye-gaze services was required to afford in-service education, follow-up services, and loaning programs for sustainable implementation. The facilitators and barriers could guide researchers and practitioners to enhance the implementation of eye-gaze technology.

Lipid-Lowering Drug Gemfibrozil Protects Mice from Tay-Sachs Disease via Peroxisome Proliferator-Activated Receptor α.

Tay-Sachs disease (TSD) is a progressive heritable neurodegenerative disorder characterized by the deficiency of the lysosomal β-hexosaminidase enzyme (Hex-/-) and the storage of GM2 ganglioside, as well as other related glycoconjugates. Along with motor difficulties, TSD patients also manifest a gradual loss of skills and behavioral problems, followed by early death. Unfortunately, there is no cure for TSD; however, research on treatments and therapeutic approaches is ongoing. This study underlines the importance of gemfibrozil (GFB), an FDA-approved lipid-lowering drug, in inhibiting the disease process in a transgenic mouse model of Tay-Sachs. Oral administration of GFB significantly suppressed glial activation and inflammation, while also reducing the accumulation of GM2 gangliosides/glycoconjugates in the motor cortex of Tay-Sachs mice. Furthermore, oral GFB improved behavioral performance and increased the life expectancy of Tay-Sachs mice. While investigating the mechanism, we found that oral administration of GFB increased the level of peroxisome proliferator-activated receptor α (PPARα) in the brain of Tay-Sachs mice, and that GFB remained unable to reduce glycoconjugates and improve behavior and survival in Tay-Sachs mice lacking PPARα. Our results indicate a beneficial function of GFB that employs a PPARα-dependent mechanism to halt the progression of TSD and increase longevity in Tay-Sachs mice.

The Impact of Childhood Trauma on Sensory Processing and Connected Motor Planning and Skills: A Scoping Review

BackgroundTraumatic experiences during childhood have been suggested to alter the course of sensory and motor development due to the impact on neural connections within the brain at integral periods. This connection has been alluded to in literature and is discussed anecdotally by practitioners suggesting the impact is commonly seen in practice. Previous scoping reviews in this area have focused solely on the process of sensory modulation without exploring the connection to motor planning.ObjectiveThis scoping review considers what is known from the existing literature about the impact of childhood trauma on sensory processing and motor skills.MethodThis scoping review followed the JBI methodology for scoping reviews (Peters et al., 2020), searching CINAHL plus, Proquest, Scopus, PsycINFO, EThOS, as well as a search of the reference lists of the articles and citation chaining, to locate both published and unpublished sources. Articles were reviewed by two reviewers independently, with a third reviewer verifying those that met inclusion criteria where there was disagreement.ResultsSix articles were identified that met the inclusion criteria for the study. While all included studies suggested the concurrence of sensory processing and motor difficulties in individuals who have experienced childhood trauma they did not conclusively make the link between the two suggesting an overall low level of evidence. Commonalities were identified in relation to the areas of the brain impacted and the nature of difficulties experienced with some suggestion of this varying according to stage of development and the specific nature of the trauma.ConclusionsThis study suggests emerging evidence in relation to the connection between trauma, sensory processing and motor development but that further empirical research is needed to verify this and inform practice.

Investigating how prior knowledge influences perception and action in developmental coordination disorder.

Developmental coordination disorder (DCD) is characterised by a broad spectrum of difficulties in performing motor tasks. It has recently been proposed that a specific deficit in sensorimotor prediction and feedforward planning might underpin these motoric impairments. The purpose of this study was to use a naturalistic object lifting paradigm to examine whether deficits in sensorimotor prediction might underpin the broad spectrum of difficulties individuals with DCD face when interacting with objects in their environment. We recruited 60 children with probable DCD and 61 children without DCD and measured perceptions of heaviness and fingertip force rate application when interacting with objects which varied in their apparent weight. If deficits in sensorimotor prediction do underpin the broad-ranging motor difficulties seen in DCD, we would expect to see a reduced effect of visual size cues on fingertip force rates and illusory misperceptions of object heaviness. We found no evidence of differences in any metrics of sensorimotor prediction between children with (n = 46) and without DCD (n = 61). Furthermore, there was no correlation between any metrics of sensorimotor prediction and motor performance (as assessed by the standard diagnostic movement assessment battery). Illusory misperceptions of object weight also did not appear to differ between groups. These findings suggest that issues with sensorimotor prediction are unlikely to affect the performance of simple real-world movements in those with DCD.

Effectiveness of CO-OP group intervention for children with developmental coordination disorder: single-case experimental design study protocol

IntroductionWith the Cognitive Orientation to daily Occupational Performance (CO-OP) approach, children with developmental coordination disorder learn to use a problem-solving strategy to deal with their motor difficulties and perform daily...

<i>In Vitro</i> Pharmacological Evaluation of Fulvic Acid and Humic Acid Novel Combination in Amyloid Beta Intoxicated SH-SY5Y Cell Lines Model of Alzheimer’s Disease

Alzheimer’s disease is the most widespread advancing neurodegenerative disorder, and it is estimated that more than 50 million people have been affected worldwide. It is characterized by dementia, loss of sensory and motor function and difficulty in performing work. NMDA antagonists and acetylcholinesterase inhibitors are currently being used as treatment options for AD, but the treatment would not decline the disease progression as well as neurodegeneration. We used a unique humic acid and Fulvic acid mixture in the current investigation for the treatment of amyloid-β intoxicated Alzheimer’s in vitro model in SH-SY5Y cell line. Humic acid and fulvic acids are organic substances which will be produced by microorganism from the biomass such as dead matter of animal as well as plants. Both the components were used in the 1:1 ratio against AD induced cell line with optimum concentration 50μM/ml of each compound. The inflammatory mediators like Reactive Oxygen Species (ROS) were estimated using flow cytometry - H2DCFDA staining assay and cytokines such as TNF-α and IL-1β levels were estimated using ELISA. The results obtained from present study implicating that the humic acid and fulvic acids and their novel combinations lessen the ROS, cytokines level and decreased the apoptosis levels there by it exhibiting the neuro-protective mechanism via inhibiting neuro-inflammatory pathway in AD.

A Process Analysis of Rey-Osterrieth Complex Figure Test Performance Using the Boston Qualitative Scoring System in HIV-Associated Neurocognitive Disorders.

Deficits in episodic verbal memory are commonly observed in persons with HIV (PWH) disease, in whom they are characterized by dysregulation of the executive aspects of encoding and retrieval and adversely impact everyday functioning. Deficits in episodic visual memory are also apparent in PWH, but we know less about their cognitive architecture. This study used the Boston Qualitative Scoring System (BQSS) for the Rey-Osterrieth Complex Figure (ROCF) to examine visual learning and recall in 43 individuals without HIV and 141 PWH who completed a full research neuropsychological, psychiatric, and medical assessment. A mixed model covarying for education and estimated verbal IQ showed that participants with HIV-associated neurocognitive disorders (HAND) performed worse than PWH without neurocognitive disorders and HIV- participants at comparable medium-to-large effect sizes across the Copy, Immediate, and Delayed trials of the BQSS-ROCF, suggesting a primary encoding deficit. A component process analysis of the BQSS-ROCF Copy Trial revealed that participants with HAND had specific difficulties with configural accuracy, cluster accuracy, and cluster placement. Within the PWH sample, measures of motor coordination and executive functions emerged as independent predictors of BQSS-ROCF Copy Trial performance. Findings extend prior research by showing that HAND may be associated with a primary encoding deficit for complex visuomotor learning and memory tasks that is driven by a combination of visuospatial, motor, and executive difficulties.

Review on Accessibility of Scissors for the Left-handed and Ambidextrous, and People with Fine Motor Difficulties in the Digital Era

Review on Accessibility of Scissors for the Left-handed and Ambidextrous, and People with Fine Motor Difficulties in the Digital Era

Intrauterine Growth and Offspring Neurodevelopmental Traits

Conventional epidemiological analyses have suggested that lower birth weight is associated with later neurodevelopmental difficulties; however, it is unclear whether this association is causal. To investigate the relationship between intrauterine growth and offspring neurodevelopmental difficulties. MoBa is a population-based pregnancy cohort that recruited pregnant women from June 1999 to December 2008 included approximately 114 500 children, 95 200 mothers, and 75 200 fathers. Observational associations between birth weight and neurodevelopmental difficulties were assessed with a conventional epidemiological approach. Mendelian randomization analyses were performed to investigate the potential causal association between maternal allele scores for birth weight and offspring neurodevelopmental difficulties conditional on offspring allele scores. Birth weight and maternal allele scores for birth weight (derived from genetic variants robustly associated with birth weight) were the exposures in the observational and mendelian randomization analyses, respectively. Clinically relevant maternal ratings of offspring neurodevelopmental difficulties at 6 months, 18 months, 3 years, 5 years, and 8 years of age assessing language and motor difficulties, inattention and hyperactivity-impulsivity, social communication difficulties, and repetitive behaviors. The conventional epidemiological sample included up to 46 970 offspring, whereas the mendelian randomization sample included up to 44 134 offspring (median offspring birth year, 2005 [range, 1999-2009]; mean [SD] maternal age at birth, 30.1 [4.5] years; mean [SD] paternal age at birth, 32.5 [5.1] years). The conventional epidemiological analyses found evidence that birth weight was negatively associated with several domains at multiple offspring ages (outcome of autism-related trait scores: Social Communication Questionnaire [SCQ]-full at 3 years, β = -0.046 [95% CI, -0.057 to -0.034]; SCQ-Restricted and Repetitive Behaviors subscale at 3 years, β = -0.049 [95% CI, -0.060 to -0.038]; attention-deficit/hyperactivity disorder [ADHD] trait scores: Child Behavior Checklist [CBCL]-ADHD subscale at 18 months, β = -0.035 [95% CI, -0.045 to -0.024]; CBCL-ADHD at 3 years, β = -0.032 [95% CI, -0.043 to -0.021]; CBCL-ADHD at 5 years, β = -0.050 [95% CI, -0.064 to -0.037]; Rating Scale for Disruptive Behavior Disorders [RS-DBD]-ADHD at 8 years, β = -0.036 [95% CI, -0.049 to -0.023]; RS-DBD-Inattention at 8 years, β = -0.037 [95% CI, -0.050 to -0.024]; RS-DBD-Hyperactive-Impulsive Behavior at 8 years, β = -0.027 [95% CI, -0.040 to -0.014]; Conners Parent Rating Scale-Revised [Short Form] at 5 years, β = -0.041 [95% CI, -0.054 to -0.028]; motor scores: Ages and Stages Questionnaire-Motor Difficulty [ASQ-MOTOR] at 18 months, β = -0.025 [95% CI, -0.035 to -0.015]; ASQ-MOTOR at 3 years, β = -0.029 [95% CI, -0.040 to -0.018]; and Child Development Inventory-Gross and Fine Motor Skills at 5 years, β = -0.028 [95% CI, -0.042 to -0.015]). Mendelian randomization analyses did not find any evidence for an association between maternal allele scores for birth weight and offspring neurodevelopmental difficulties. This study found that the maternal intrauterine environment, as proxied by maternal birth weight genetic variants, is unlikely to be a major determinant of offspring neurodevelopmental outcomes.

Long-term motor development after hypothermia-treated hypoxic-ischaemic encephalopathy

AimsTo describe longitudinal motor development in children treated with therapeutic- hypothermia (TH) due to neonatal hypoxic-ischaemic encephalopathy (HIE) and to explore motor functioning in early adolescence. Material and methodsChildren treated with TH due to HIE during 2007–2009, in Stockholm, participated in a prospective follow-up study. Motor development was assessed on four occasions, reported as percentiles and at mean ages. Alberta Infant Motor Scale was used at 0.35 years of age, Bayley Scales of Infant and Toddler Development-III at 2.1 years and Movement Assessment Battery for Children (MABC-2) at 7.3 and 11.1 years of age. MABC-2 Checklist was completed by parents at 7.3 and 11.1 years of age. General cognition was assessed using Wechsler Intelligence Scales for Children Fifth Edition (WISC-V). ResultsThirty-one percent (14/45) of the children had a motor score ≤ 15th percentile, indicating risk of motor difficulties at 11.1 years of age, and simultaneously the scores from parents of 52% (23/44), indicating risk of motor difficulties in the everyday context. These children had significantly lower motor percentile at 2.1 years of age, but within the normal range. Longitudinal motor development displayed a weak association with WISC-V Full Scale IQ (rs0.38, p = 0.013). ConclusionAmong survivors of hypothermia-treated HIE free of moderate/severe cerebral palsy, a third had MABC-2 scores indicating risk of motor difficulties at 11.1 years of age. As motor difficulties became more apparent over time, we suggest that children treated with TH due to neonatal HIE should be followed into at least middle school age.

Jazz and body percussion. A proposal of creative strategies with the BAPNE method

Neuromotricity is one of the most effective resources to possibly work cognitive and executive functions, highlighting its activities through the dual task in the BAPNE method. There is bibliography in Web of Science that provides positive data in several investigations with different types of population. Through the BAPNE method, the activities are structured in a specific way to ensure the learning process. In this way, with an adequate progressive sequence in the motor and cognitive difficulty, the independence of the upper and lower limbs and the voice is sought. The learning process of jazz music resides mainly in imitation, but also in the acquisition of knowledge and skills, the creativity of the teacher is as important as that of the learner, so it is proposed that once a certain level is reached, the latter assumes the role of leader in the activity. From the 32-bar AABA form of the Rhythm Changes, multiple activities can be created, supporting coordination, dissociation and laterality processes, among many other aspects, and thus providing a greater number of tools to professionals in different fields such as education and therapy to better and more widely understand the roots of jazz music. Keywords: Neuromotricity, BAPNE method, Jazz, Dual task, Body Percussion, Creativity.

Bursting with Potential: How Sensorimotor Beta Bursts Develop from Infancy to Adulthood.

Beta activity is thought to play a critical role in sensorimotor processes. However, little is known about how activity in this frequency band develops. Here, we investigated the developmental trajectory of sensorimotor beta activity from infancy to adulthood. We recorded EEG from 9-month-old, 12-month-old, and adult humans (male and female) while they observed and executed grasping movements. We analyzed "beta burst" activity using a novel method that combines time-frequency decomposition and principal component analysis. We then examined the changes in burst rate and waveform motifs along the selected principal components. Our results reveal systematic changes in beta activity during action execution across development. We found a decrease in beta burst rate during movement execution in all age groups, with the greatest decrease observed in adults. Additionally, we identified three principal components that defined waveform motifs that systematically changed throughout the trial. We found that bursts with waveform shapes closer to the median waveform were not rate-modulated, whereas those with waveform shapes further from the median were differentially rate-modulated. Interestingly, the decrease in the rate of certain burst motifs occurred earlier during movement and was more lateralized in adults than in infants, suggesting that the rate modulation of specific types of beta bursts becomes increasingly refined with age.SIGNIFICANCE STATEMENT We demonstrate that, like in adults, sensorimotor beta activity in infants during reaching and grasping movements occurs in bursts, not oscillations like thought traditionally. Furthermore, different beta waveform shapes were differentially modulated with age, including more lateralization in adults. Aberrant beta activity characterizes various developmental disorders and motor difficulties linked to early brain injury, so looking at burst waveform shape could provide more sensitivity for early identification and treatment of affected individuals before any behavioral symptoms emerge. More generally, comparison of beta burst activity in typical versus atypical motor development will also be instrumental in teasing apart the mechanistic functional roles of different types of beta bursts.

Structural validity and internal consistency of an outcome measure to assess self-reported educator capacity to support children with motor difficulties

BackgroundPartnering for Change (P4C) is a school-based occupational therapy service intended to build the capacity of educators to support children with motor difficulties.AimsThis paper describes the development of the Partnering for Change Educator Questionnaire and evaluates its structural validity and internal consistency.Methods and proceduresThe P4C Educator Questionnaire was completed by 1,216 educators four times across 2 years. Data from the initial time point were analysed via exploratory factor analysis (n = 436). Subsequently, Cronbach’s alpha and mean interitem correlations were calculated. Finally, the proposed factor structure was confirmed by testing it against data from times two through four using confirmatory factor analysis (n = 688).Outcomes and resultsA three-factor structure was evident and confirmed in hypothesis testing. The factor structure was interpretable according to the framework for building educator capacity used in this study. Internal consistency was high, with the total scale outperforming each subscale.Conclusions and implicationsA novel measure of educator self-reported capacity to support students with motor difficulties demonstrated structural validity and internal consistency. We currently recommend use as a complete scale accompanied by additional validation research.

In Vivo Ultrafast Doppler Imaging Combined with Confocal Microscopy and Behavioral Approaches to Gain Insight into the Central Expression of Peripheral Neuropathy in Trembler-J Mice.

The main human hereditary peripheral neuropathy (Charcot-Marie-Tooth, CMT), manifests in progressive sensory and motor deficits. Mutations in the compact myelin protein gene pmp22 cause more than 50% of all CMTs. CMT1E is a subtype of CMT1 myelinopathy carrying micro-mutations in pmp22. The Trembler-J mice have a spontaneous mutation in pmp22 identical to that present in CMT1E human patients. PMP22 is mainly (but not exclusively) expressed in Schwann cells. Some studies have found the presence of pmp22 together with some anomalies in the CNS of CMT patients. Recently, we identified the presence of higher hippocampal pmp22 expression and elevated levels of anxious behavior in TrJ/+ compared to those observed in wt. In the present paper, we delve deeper into the central expression of the neuropathy modeled in Trembler-J analyzing in vivo the cerebrovascular component by Ultrafast Doppler, exploring the vascular structure by scanning laser confocal microscopy, and analyzing the behavioral profile by anxiety and motor difficulty tests. We have found that TrJ/+ hippocampi have increased blood flow and a higher vessel volume compared with the wild type. Together with this, we found an anxiety-like profile in TrJ/+ and the motor difficulties described earlier. We demonstrate that there are specific cerebrovascular hemodynamics associated with a vascular structure and anxious behavior associated with the TrJ/+ clinical phenotype, a model of the human CMT1E disease.

B - 43 Case Study: Native Hawaiian/Pacific Islander Female Veteran with Dementia with Lewy Bodies.

Recent research suggests there is a lack of consensus regarding current data on the racial/ethnic profiles of cognitively impaired persons with dementia with Lewy bodies (DLB) despite DLB being among the most common neurodegenerative dementias. This case study reviews a Native Hawaiian/Pacific Islander (NHPI) with probable DLB and discusses challenges encountered to emphasize the importance of appropriate normative data to help detect DLB in diverse populations. A 78-year-old NHPI female veteran presented for repeat neuropsychological evaluation to track her cognitive symptoms. Chief complaints included concurrent cognitive and motor difficulties, fully formed visual hallucinations, nighttime confusion, and reduplicative paramnesias which have significantly impacted her instrumental activities of daily living. Neuropsychological testing is suggestive of progressive decline in several cognitive domains, including visuospatial ability, executive functioning, semantic fluency, and verbal and visual learning and memory. Consistent with a DLB diagnosis, her cognitive symptoms emerged concurrently with motor symptom onset. There is also evidence of significant visuospatial and executive difficulties, as well as previously reported reduplicative paramnesia, confusion, and weekly fully-formed hallucinations. Additionally, there is evidence of concurrent parkinsonism's such as bradykinesia, rigidity, hypophonia, and tremor. The constellation of symptoms reported by the patient, combined with the results of neuropsychological assessment, was highly congruent with prototypical DLB; however, lack of proper normative data to accurately assess for decline in her scores led to significant caution in interpretation of her neuropsychological performance. This case demonstrates the importance of proper normative data in diverse populations and the role of neuropsychological evaluations in specific cultural contexts.

Long-Term Outcomes for Individuals With Childhood Apraxia of Speech.

The study's primary aims were to describe the long-term speech outcomes for adolescents and young adults with a history of childhood apraxia of speech (CAS) and to examine the association of persistent speech sound errors with measures of literacy skills, phonological processing, motor speech production, and parent report of early motor difficulty. Data from a large longitudinal 25-year study were used to explore outcomes for 32 individuals with a history of CAS, ages 12;6 (years;months) to 25 years (M = 17.4, SD = 4.7). Persistent and nonpersistent groups were compared on decoding, phonological processing, multisyllabic word repetition, diadochokinetic rate, and parent report of motor involvement. Parametric (Welch's t tests) and nonparametric tests (Wilcoxon and Fisher exact tests) were used to identify differences between the groups' distributions. Developmental trajectories of speech production were plotted. Outcomes for individuals with CAS are highly variable, with some demonstrating speech sound errors into adolescence and young adulthood. Speech sound errors were primarily on later developing sounds. Persistence was significantly associated with early motor difficulties. Difficulties with multisyllabic words, phonological processing, and literacy were often present regardless of persistence or nonpersistence of speech errors. Children with CAS are at risk for persistent speech sound errors into adulthood. For children showing limited progress with more traditional speech therapy, alternative interventions should be explored. Individuals with persistent speech sound errors are more likely to have a history of early motor deficits. Regardless of persistence, participants with CAS demonstrated ongoing weaknesses in literacy, phonological processing skills, and complex speech production tasks.

Is There a Role of Inferior Frontal Cortex in Motor Timing? A Study of Paced Finger Tapping in Patients with Non-Fluent Aphasia.

The aim of the present study was to investigate the deficits in timing reproduction in individuals with non-fluent aphasia after a left hemisphere lesion including the inferior frontal gyrus, in which Broca's region is traditionally localised. Eighteen stroke patients with non-fluent aphasia and twenty-two healthy controls were recruited. We used a finger-tapping Test, which consisted of the synchronisation and the continuation phase with three fixed intervals (450 ms, 650 ms and 850 ms). Participants firstly had to tap simultaneously with the device's auditory stimuli (clips) (synchronisation phase) and then continue their tapping in the same pace when the stimuli were absent (continuation phase). Patients with aphasia demonstrated less accuracy and greater variability during reproduction in both phases, compared to healthy participants. More specifically, in the continuation phase, individuals with aphasia reproduced longer intervals than the targets, whereas healthy participants displayed accelerated responses. Moreover, patients' timing variability was greater in the absence of the auditory stimuli. This could possibly be attributed to deficient mental representation of intervals and not experiencing motor difficulties (due to left hemisphere stroke), as the two groups did not differ in tapping reproduction with either hand. Given that previous findings suggest a potential link between the IFG, timing and working memory, we argue that patients' extra-linguistic cognitive impairments should be accounted for, as possible contributing factors to timing disturbances.

Adolescents with ADHD and co-occurring motor difficulties show a distinct pattern of maturation within the corticospinal tract from those without: A longitudinal fixel-based study.

It is well documented that attention-deficit hyperactivity disorder (ADHD) often presents with co-occurring motor difficulties. However, little is known about the biological mechanisms that explain compromised motor skills in approximately half of those with ADHD. To provide insight into the neurobiological basis of poor motor outcomes in ADHD, this study profiled the development of white matter organization within the cortico-spinal tract (CST) in adolescents with ADHD with and without co-occurring motor problems, as well as non-ADHD control children with and without motor problems. Participants were 60 children aged 9-14 years, 27 with a history of ADHD and 33 controls. All underwent high-angular resolution diffusion MRI data at up to three time points (115 in scans total). We screened for motor impairment in all participants at the third time point (≈14 years) using the Developmental Coordination Disorder Questionnaire (DCD-Q). Following pre-processing of diffusion MRI scans, fixel-based analysis was performed, and the bilateral CST was delineated using TractSeg. Mean fiber density (FD) and fiber cross-section (FC) were extracted for each tract at each time-point. To investigate longitudinal trajectories of fiber development, linear mixed models were performed separately for the left and right CST, controlling for nuisance variables. To examine possible variations in fiber development between groups, we tested whether the inclusion of group and the interaction between age and group improved model fit. At ≈10 years, those with ADHD presented with lower FD within the bilateral CST relative to controls, irrespective of their prospective motor status. While these microstructural abnormalities persisted into adolescence for individuals with ADHD and co-occurring motor problems, they resolved for those with ADHD alone. Divergent maturational pathways of motor networks (i.e., the CST) may, at least partly, explain motor problems individuals with ADHD.