Age-related differences in predictive response timing in children: Evidence from regularly relative to irregularly paced reaction time performance

Optimizing Reaction Time in Relation to Manual and Foot Laterality in Children Using the Fitlight Technological Systems

The purpose of the study was to design and implement, in the physical and sports education process and in the motor evaluation process, a program of exercises and specific tests to optimize reaction time by using the Fitlight technological systems in relation to the manual and foot laterality of the pupils and identification of gender differences regarding the development of reaction speed. The study included 231 pupils, between 10 and 11 years old, who were divided into two groups according to gender, as follows: the male sample included 109 (97.32%) subjects, and the female sample included 103 (94.45%) participants. All subjects were identified with right manual and foot laterality. Both samples performed a specific exercise program to optimize reaction time in relation to manual and foot laterality by using Fitlight technologies. In the study, four tests were applied in order to evaluate reaction times using Fitlight, two in relation to the manual laterality and two with foot laterality, and the results were statistically processed with IBM SPPS Statistic 24 (IBM Corp., Armonk, NY, USA). Through the comparative analysis of the samples and the progress aimed at optimizing the reaction time specific to our study, it was found that the female sample recorded greater progress at the level of manual laterality, both for the right hand and for the left one, while the sample of boys recorded significant progress in terms of improving reaction time at the level of right and left foot laterality. At the foot laterality level, the results for the executions with the right foot were better in the simple test with four Fitlight spotlights in a line, and for the complex test, with eight Fitlight spotlights in a square, the results were better in the executions with the left foot. This reveals the fact that the greater the execution complexity, the better the motor prevalence on the left side.

Compensation to real-time temporal auditory feedback perturbation depends on syllable position

Auditory feedback perturbations involving spectral shifts indicated a crucial contribution of auditory feedback to planning and execution of speech. However, much less is known about the contribution of auditory feedback with respect to temporal properties of speech. The current study aimed at providing insight into the representation of temporal properties of speech and the relevance of auditory feedback for speech timing. Real-time auditory feedback perturbations were applied in the temporal domain, viz., stretching and compressing of consonant-consonant-vowel (CCV) durations in onset + nucleus vs vowel-consonant-consonant (VCC) durations in nucleus + coda. Since CCV forms a gesturally more cohesive and stable structure than VCC, greater articulatory adjustments to nucleus + coda (VCC) perturbation were expected. The results show that speakers compensate for focal temporal feedback alterations. Responses to VCC perturbation were greater than to CCV perturbation, suggesting less deformability of onsets when confronted with temporally perturbed auditory feedback. Further, responses to CCV perturbation rather reflected within-trial reactive compensation, whereas VCC compensation was more pronounced and indicative of adaptive behavior. Accordingly, planning and execution of temporal properties of speech are indeed guided by auditory feedback, but the precise nature of the reaction to perturbations is linked to the structural position in the syllable and the associated feedforward timing strategies.

KTK MOTOR TEST: REVIEW OF THE MAIN INFLUENCING VARIABLES

OBJECTIVE

To analyze the scientific literature regarding the effects of external variables on KTK motor test scores and to verify which motor tests are associated with KTK.

DATA SOURCES

Four databases (PubMed, Science Direct, Scientific Electronic Library Online - SciELO - and Latin American and Caribbean Health Sciences Literature - LILACS) were used to search for studies in which the descriptors Körperkoordinationstest für Kinder and KTK were presented in the title, abstract and keywords. Inclusion criteria were: articles published in English or Portuguese from January 2006 to December 2016; free access to the article in full and texts available online; presenting the descriptor terms mentioned above in the title, abstract or keywords; containing sample with children and adolescents aged 4 to 16 years old; being indexed in a journal with a rating of B2 or higher (WebQualis; Qualis 2016) for the area of physical education. The following were excluded: studies in books, chapters of books, theses and dissertations; duplicate scientific articles; conference summaries; articles published in proceedings and abstracts of congresses.

DATA SYNTHESIS

After the three stages of selection (identification, screening and eligibility) and the criteria proposed at the PICOS scale, 29 studies were included in this review.

CONCLUSIONS

Body composition and the regular practice of physical activities were the variables that presented the greatest influence on KTK. It is important that health professionals working with the pediatric public encourage regular physical activity to improve body composition and, thus, to obtain better KTK scores. Additionally, the Movement Assessment Battery for Children (M-ABC) test had the highest positive correlation with the KTK test.

Brain Connectomics of Visual-Motor Deficits in Children with Developmental Coordination Disorder

OBJECTIVE

To extend preliminary findings on associated white matter deficits and structural connectivity in children with developmental coordination disorder (DCD).

STUDY DESIGN

Diffusion magnetic resonance imaging-based tractography was used to identify abnormal microstructural properties of specific sensorimotor white matter tracts in 21 children with DCD between 8 and 10 years of age and 20 age- and sex-matched typically developing controls. Graph theoretical analyses were applied to evaluate whole brain connectomics. Associations were also calculated between the tractography/connectome results and visual-motor performance, as measured with the Beery-Buktenica Developmental Test of Visual Motor Integration.

RESULTS

Significant positive correlations were obtained between visual-motor trace scores and fractional anisotropy (FA) in the retrolenticular limb of the internal capsule within the group with DCD. Moreover, lower FA in sensorimotor tracts and altered structural connectivity were observed for children with DCD. Compared with controls, subjects with DCD showed decreases in clustering coefficient, and global and local efficiency, suggesting weaker structural network segregation and integration. The degree of decreased global efficiency was significantly associated with poor visual-motor tracing outcomes, above and beyond FA reductions. Specifically, nodal efficiency at the cerebellar lobule VI and right parietal superior gyrus were found significant predictors to discriminate between children with DCD and those with typical development.

CONCLUSIONS

Specific white matter alterations and network topology features associate with visual-motor deficits and DCD diagnosis indicating the clinical potential of diffusion magnetic resonance imaging-based metrics for diagnosing DCD.

Human strategies for solving a time-place learning task: the role of counting and following verbal cues

Two experiments were conducted to assess the emergence of time-place learning in humans. In experiment 1, a computer based software was designed in which participants had to choose to enter one of four rooms in an abandoned house search for a zombie every 3-15s. Zombies could be found in only one of these rooms every trial in 3 min periods during the 12 min sessions. After 4 training sessions, participants were exposed to a probe session in which zombies could be found in any room on every trial. Almost all participants behaved as if they were timing the availability intervals: they anticipated the changes in the location of the zombie and they persisted in their performance patterns during the probe session; however, verbal reports revealed that they were counting the number of trials in each period in order to decide when to switch between rooms. In the second experiment, the task was modified in two ways: counting was made harder by using three different intertrial ranges within each session: 2-6s, 2-11s and 2-16s. Second, labels were displaced during the final session to assess whether participants learned to click on a given place or to follow a set of verbal cues. We found that participants did not notice the label changes suggesting that they learned to click on a given place, and that a win/stay-lose/shift strategy was clearly used to decide when to switch rooms in the second experiment. The implications of verbal behavior when assessing time-place learning with humans and the possible differences in this process between humans and animals are discussed.

Deficient motor timing in children with neurofibromatosis type 1

Neurofibromatosis type 1 (NF1) is one of the most common single-gene disorders affecting fine and visual-motor skills. This case-control study investigated motor timing as a possible related performance deficit in children with NF1. A visual-motor reaction time (VRT) test was administered in 20 NF1 children (mean age 9 years 7 months) and 20 age- and gender-matched typically developing (TD) children. Copying and tracing performance were evaluated using the Beery-Buktenica Developmental Test of Visual-Motor Integration (Beery VMI). Children with NF1 responded with an increased reaction time (RT) to temporally predictive stimuli compared to TD children, whereas RT at unpredictive stimuli did not differ between groups. Motor timing indexed by the RT decrease at predictive stimuli significantly associated with the Beery VMI copy and tracing outcomes. Deficient motor timing as an actual symptom may add to further research on the pathogenesis of NF1-associated motor impairment and the development of more effective treatment.

Major changes in a rhythmic ball-bouncing task occur at age 7 years

The aim of the study was to investigate the development of a rhythmical skill of children aged from 5 to 12 years old. Five age groups (5–6, 7–8, 9–10, 11–12, and young adults) performed a virtual ball bouncing task (16 forty-second long test trials). Task performances, racket oscillation, ball-racket impacts as well as the ball-racket coupling were analysed. The results showed a change in both performance and behaviour at the age of 7 years old. Before this age, children exhibited restricted perceptual-motor coordination with a high frequency of racket oscillation and a poor level of performance. After the age of 7, cycle-to-cycle adaptive coordination based on visual information was progressively acquired leading to increasing performance levels with age. Overall these results revealed a rapid change in capability to perform the ball bouncing task across age with a late emergence of the required coordination and significant change in the coordination at the age of 7.

Neural underpinnings of impaired predictive motor timing in children with Developmental Coordination Disorder

A dysfunction in predictive motor timing is put forward to underlie DCD-related motor problems. Predictive timing allows for the pre-selection of motor programmes (except 'program' in computers) in order to decrease processing load and facilitate reactions. Using functional magnetic resonance imaging (fMRI), this study investigated the neural correlates of motor timing in DCD (n=17) and typically developing children (n=17). The task involved motor responses to sequences of visual stimuli with predictive or unpredictive interstimulus intervals (ISIs). DCD children responded with a smaller reaction time (RT) advantage to predictive ISIs compared to typically developing children. Typically developing children exhibited higher activation in the right dorsolateral prefrontal cortex (DLPFC) and right inferior frontal gyrus (IFG) for responses at unpredictive as opposed to predictive ISIs, whereas activations in DCD children were non-differentiable. Moreover, DCD children showed less activation than typically developing children in the right DLPFC, the left posterior cerebellum (crus I) and the right temporo-parietal junction (TPJ) for this contrast. Notably, activation in the right temporo-parietal junction (TPJ) positively correlated with RT as an indicator of processing load in both groups. These data indicate that motor performance in DCD children requires extra processing demands due to impaired predictive encoding.