RESUMO: Este estudo teve como objetivo analisar a lateralidade e a destreza manual em crianças com Transtorno do Espectro Autista (TEA). Do ponto de vista da motricidade humana, a lateralidade contribui para o processo de maturação motora. Figura-se entre as principais características do autismo o atraso nas habilidades motoras grossas e finas, com piora progressiva no quadro. Analisar o nível de lateralidade do indivíduo com TEA torna-se importante por possibilitar uma direção na intervenção motora com o intuito de melhorar a funcionalidade do autista e sua qualidade de vida. A amostra deste estudo foi composta por oito crianças, alunos de uma instituição de ensino pública, do sexo masculino, com idade média de 8,75±1,83 anos e diagnosticadas com TEA com base no DSM-V. Os resultados mostraram que os participantes do estudo parecem apresentar lateralidade destra e, também, melhor desempenho com a mão preferida em uma tarefa de destreza manual. Observou-se que, na tarefa que exigiu maior atenção e destreza, a diferença no desempenho das mãos foi significativa. Já na tarefa com menor demanda atencional e de destreza manual, o desempenho entre as mãos não foi significante, porém foi nesse momento que foram observados os maiores erros na execução. A motivação pode ser uma variável fundamental para o desempenho motor em tarefas que avaliam o tempo de execução. É importante uma maior ênfase no desenvolvimento da motricidade desses indivíduos durante a fase escolar para diminuir as dificuldades motoras e, consequentemente, melhorar a qualidade de vida, sensação de bem-estar, autonomia e interação social.

ABSTRACT: This study aimed to analyze laterality and manual dexterity in children with Autism Spectrum Disorder (ASD). From the point of view of human motor skills, laterality contributes to the motor maturation process. Among the main characteristics of autism is the delay in gross and fine motor skills, with progressive worsening in the condition. Analyzing the level of laterality of the individual with ASD becomes important because it allows a direction in the motor intervention in order to improve the functionality and quality of life of the autistic person. The sample of this study was composed of eight children, students of a public education institution, male, with an average age of 8.75 ± 1.83 years old and diagnosed with ASD based on the DSM-V. The results showed that the study participants seem to have right handedness and also better performance with the preferred hand in a manual dexterity task. It was observed that, in the task that demanded more attention and dexterity, the difference in hand performance was significant. In the task with the lowest attentional demand and manual dexterity, the performance between the hands was not significant; however, it was at that moment that the biggest mistakes in execution were observed. Motivation can be a fundamental variable for motor performance in tasks that assess execution time. It is important to emphasize the development of the motor skills of these individuals during the school phase to reduce motor difficulties and, consequently, improve quality of life, sense of well-being, autonomy and social interaction.

Resumo O objetivo do presente estudo foi avaliar as diferenças no desempenho entre as condições de foco de atenção externo e interno e uma condição de demonstração online. Adicionalmente, se essas diferenças seriam observadas em um nível neuromuscular por meio da análise EMG, além das medidas de resultados tradicionais. Foi levantada a hipótese que sob a condição de demonstração os participantes teriam um desempenho melhor do que sob as condições de foco externo e interno. Também foi levantado a hipótese que a condição de demonstração apresentaria menor atividade EMG do que as condições de foco externo e interno. Além disso, esperava-se corrobora os benefícios do foco externo em relação ao foco interno, tanto nas medidas de resultado quanto de produto. Seis participantes do sexo masculino realizaram uma extensão de perna bilateral nas condições: foco de atenção interno, foco de atenção externo e condições de demonstração online. Os tempos de meta de contrações musculares foram definidos para ação muscular concêntrica (4 segundos) e ação muscular excêntrica (2 segundos). Um eletrogoniômetro foi usado para registrar a ativação muscular (medidas de produção) e o erro temporal foi usado para observar o desempenho (medidas de resultado). Os resultados mostraram que a condição de demonstração online obteve melhor desempenho do que a condição de foco externo e uma ativação muscular reduzida. No entanto, não foram encontradas diferenças entre o foco interno e as outras condições experimentais. Esses achados avançam no entendimento dos mecanismos que sustentam o foco de atenção, como o proposto pela Constrained Action Hypothesis.

Abstract The purpose of the present study was to examine whether there would be performance differences between external and internal focus of attention conditions and an online demonstration condition, and if these differences would be observed at a neuromuscular level through EMG analysis, in addition to traditional outcome measures. We hypothesized that under the demonstration condition participants would perform better than under external and internal focus conditions. We also hypothesized that demonstration condition would show smaller EMG activity than external and internal focus conditions. Furthermore, we hope to replicate the benefits of external focus in relation to internal focus, both in outcome and product measures. Six male participants performed a bilateral leg extension under internal focus of attention, external focus of attention and online demonstration conditions. Muscular contractions goal times were set for concentric muscle action (4 seconds) and eccentric muscle action (2 seconds). An electrogoniometer was used to record muscular activation (production measures), and temporal error was used to observe performance (outcome measures). Results showed that online demonstration condition obtained better performance than external focus condition and a reduced muscular activation. However, differences between internal focus and the other experimental conditions were not found. These findings advance in the understanding mechanisms underpining the focus of attention, such as proposed by Constrained Action Hypothesis.

Abstract Developmental Coordination Disorder (DCD) is a neurodevelopmental condition marked by impairments in the development of motor coordination. The uncoordinated movements of children with DCD lead to performance difficulties in daily life activities and academic settings. Despite the high prevalence of this condition (2-7%) and severe consequences associated with it, DCD is not well recognized in clinical and educational practices, particularly in Brazil. This review provides an overview of DCD and the research evidence - we present definitions and characteristics associated with the condition, the diagnostic criteria, associated difficulties, frequent co-morbidities and a summary of the possible causes. Finally, we review management strategies and intervention approaches for DCD. We also discuss some of the common challenges of the field - while DCD has been largely studied in the last decade, there are still many gaps between research and practice that need to be filled. Awareness and dissemination of relevant, scientific information is necessary. In conclusion, DCD is a significant condition with a clear diagnostic criteria, and requires intervention to improve motor and functional skills, which can improve the associated difficulties as well as the physical and mental health consequences of the condition.

Resumo O tipo de prática pode influenciar o que é aprendido de uma habilidade motora. Objetivou-se investigar os efeitos da prática constante e aleatória na aprendizagem do Programa Motor Generalizado e parâmetros do saque do voleibol. A amostra foi composta por 20 crianças entre 10 e 12 anos. Os participantes realizaram um pré-teste, cujo escore foi utilizado para contrabalançar dois grupos (n=10), prática constante e aleatória. Durante a fase de aquisição, o grupo aleatório realizou 252 saques de três posições diferentes, sempre indicada ao final de cada saque e o grupo controle realizou todos os saques somente de uma posição específica. O teste de retenção mostrou que ambos os grupos aprenderam o Programa Motor Generalizado, mas a prática aleatória conduziu para uma melhor aprendizagem dos parâmetros, resultante da prática variada. Durante a prática de habilidades motoras esportivas, apesar de as práticas constante e aleatória melhorarem a aprendizagem do Programa Motor Generalizado, somente a prática aleatória melhora a aprendizagem dos parâmetros da habilidade motora.

Abstract The type of practice can influence what is learned from a motor skill. The aim of this study was to investigate the effects of the constant and random practice on the learning of Generalized Motor Program and parameters of the volleyball serve. The sample was composed of 20 children between 10 and 12 years old. The participants performed a pre-test whose score was adopted to counterbalance two groups (n=10), random practice and constant practice. During the acquisition phase, the random group performed 252 serves from three different positions, always indicated at the end of each serve, and the constant group performed all serves from only a specific position. The retention test showed that both groups learned the Generalized Motor Program, but random practice conducted to higher parameterization learning, resultant from the variable of practice. During practice of a sport motor skills, although the constant and random practice improve the learning of Generalized Motor Program, only the random practice improves learning of parameters of the motor skill.

The aim of this study was to investigate the short and long-term effects of the bandwidth KR in learning of the absolute and relative dimensions of a motor skill. Twenty-two undergraduate students divided into two groups: G15 who received KR when the relative error exceeded 15%; and G0, with KR after every trial. The study consisted of an acquisition phase, and the volunteers practiced 100 trials with a target time of 850 ms and relative of 22.2%, 44.4% and 33.3% between the first and second, second and third, third and fourth keys, respectively. This phase, KR related to relative time (relative error) was provided according to the group. KR of total target time was available to both groups after all trials. Three retention tests with ten trials were conducted 10 minutes, 24 hours and one week after the acquisition phase. The results showed that G15 had a smaller relative error than G0. This study allows concluding that bandwidth KR in relation relative time error showed its effects in the consistency of relative time. These effects persisted even after seven days after the acquisition phase in a delayed retention test.

The amorphous, mesoporous SiO2-SO3H catalyst with a surface area of 115 m2 g-1 and 1.32 mmol H+ per g was very efficient for the protonation of ketones on a 10% (m/m) basis, and the catalyst-bound intermediates can be trapped by polyalcohols to produce ketals in high yields or suffer aldol condensations within minutes under low-power microwave irradiation. The same catalyst can easily reverse the ketalization reaction.

Abstract Aims: This study aimed to investigate how different age groups of older adults perform and control movements in a goal-directed aiming task and the importance of visual feedback during these movements. Methods: Participants included 22 old adults, divided in two age groups: younger (60-70 yr) and older (80-90 yr). Subjects performed the task in a condition with vision and in a condition where vision was deprived. Results: In the vision condition, younger subjects showed smaller movement and reaction times, smaller radial errors, higher peak velocities, lower relative times to reach peak velocity than older subjects. In the vision-deprived condition the same results were found, except for radial error measure, where no significant effect for age groups was found. Conclusion: Younger subjects seemed to rely more on visual online feedback than older subjects and older subjects use other sensory sources to meet the possible deficits of information obtained by vision.

RESUMO A pesquisa objetivou a comparação da tomada de decisão de treinadores de voleibol por meio das estratégias de busca visual (número e duração das fixações visuais) em função dos seus anos de experiência. A amostra constituiu-se por trinta e quatro treinadores de voleibol (n=34) com idade média de 32,5 ± 9,4 anos. Assim, configuraram-se dois grupos: principiantes (2,8 ± 1,9 anos de prática) e experientes (19 ± 7,2 anos de prática). Para avaliação do conhecimento tático relacionado aos aspectos da tomada de decisão os treinadores realizaram a análise das cenas de ataque de extremidade do Teste de Conhecimento Tático Declarativo no Voleibol. Os resultados não apontaram diferenças significativas nas estratégias visuais, tomada de decisão e conhecimento tático declarativo na análise das cenas entre os dois grupos (p>0,05), sendo que o poder do efeito variou entre pequeno e moderado para as variáveis analisadas. Neste contexto, percebeu-se que as estratégias visuais utilizadas entre os treinadores com diferentes tempos de experiência foram semelhantes.

ABSTRACT The research aimed at comparing the decision making of volleyball coaches through visual search strategies (number and duration of visual fixations) based on their years of experience. The sample consisted of thirty-four volleyball coaches (n = 34) with a mean age of 32.5 ± 9.4 years. Thus, two groups were formed: beginners (2.8 ± 1.9 years of practice) and experienced (19 ± 7.2 years of practice). To assess the tactical knowledge related to aspects of decision-making, the coaches conducted the analysis of the end-attack scenes of the Declarative Tactical Knowledge Test in Volleyball. The results not related significant differences to the visual strategies, decision-making and declarative tactical knowledge in the analysis of the scenes between the two groups (p> 0.05), and the power of the effect ranged from small to moderate for the analyzed variables. In this context, it was noticed that the visual strategies used between the coaches with different times of experience were similar.

RESUMO Pouco se sabe a respeito da associação entre o efeito da interferência contextual (EIC) e medidas cinemáticas. O objetivo do presente estudo foi investigar o EIC nos perfis cinemáticos de velocidade e aceleração do membro superior. Vinte e dois participantes (23,7 ± 3,3 anos) foram alocados em dois grupos de prática: em blocos (GPB) e aleatória (GPA). A tarefa consistiu em acertar três alvos apresentados no monitor em três sequências pré-determinadas o mais rápido e preciso possível. O estudo foi dividido em fase de aquisição e teste de transferência. As variáveis de desempenho foram tempo de reação, tempo de movimento e tempo de resposta e as variáveis cinemáticas foram pico de velocidade, tempo relativo para o pico de velocidade e número de correções para alcançar o alvo. Os principais achados mostraram que o GPA apresentou menor tempo de movimento e de resposta do que o GPB. Análise de regressão indicou que a mudança observada ao longo da prática para a medida de pico de velocidade estava associada à mudança do tempo de reação da fase de aquisição para o teste de transferência. Como o pico de velocidade é uma medida associada à pré-programação, sugere-se que o controle central seja essencial para a observação do EIC.

ABSTRACT The association between contextual interference effect (CIE) and kinematic measures has been little investigated. The purpose of this study was to investigate the CIE on velocity and acceleration kinematic profiles of upper limb. Thirty-two subjects (23,7 ± 3,3 years) were assigned to groups of blocked practice (GPB) and random practice (GPA). The task consisted in achieve three targets in three specific sequences as quickly and accurately as possible. The study was designed in acquisition phase and transfer test. The variables of performance were reaction time, movement time, and response time and the kinematic variables were peak of speed, relative time to peak of speed, and number of peak acceleration points. The main findings showed that GPA showed lower movement time and response time than GPB. Regression analysis indicated that change in peak velocity during practice was associated to the change of the reaction time from practice to the transfer test. As peak velocity is a measure related to preprogramming, it is suggested that central control was essential to the CIE.

Abstract BACKGROUND There is aconsensus that repetition observed in constant practice producesminimalbenefits to the transfer of learning. OBJECTIVE The purpose of this study was to investigatein 3 experiments the effects of constant practicein transfer contexts. METHODOLOGY Participants were asked during acquisition phase, in all experiments, to press four keys sequentially with different requirements of absolute timing in a same relative timing structure. In the transfer tests, they were tested in a novel absolute timing criterion. RESULTS The results of experiment 1 and 2 showed that the relative timing structure was maintained only when the transfer required parameter scaling close to the parameter value practiced in acquisition. The transfer parameter that is far to the parameter practiced did not affect the movement parameterization. The result of experiment 3 showed that relative timing structure is disrupted in the transfer test when constant practice has high and low amount of practice. CONCLUSION Some specific aspects interfere in the transfer test when constant practice is experienced.

RESUMO O presente estudo investigou a influência de plateia sobre o desempenho sensoriomotor na aprendizagem do arremesso de dardo de salão. O experimento foi conduzido em dois dias distintos, cada um com uma condição específica: 1) com plateia (10 tentativas); 2) sem plateia (10 tentativas). Os 18 universitários de menor e maior desempenho foram divididos em dois grupos: prejudicado (GP) e beneficiado (GB). Nas análises de desempenho e escores de ansiedade-estado (IDATE), a ANOVA two way e pairwise identificaram interação entre grupo e condição, sendo GP com pior desempenho e maior IDATE e GB com melhor desempenho e sem alteração no IDATE na condição com plateia. Já na frequência cardíaca, não houve interação, porém efeito principal para o fator condição para ambos os grupos. Pode-se inferir que, a plateia influencia no desempenho sensoriomotor podendo ocorrer piora ou melhora a depender de características individuais.

ABSTRACT The present study investigated the influence of audience on the sensorymotor performance in learning the hall of javelin throwing. The experiment was conducted on two separate days, each with a specific condition: 1) with audience (10 attempts); 2) no audience (10 attempts). The 18 students of smaller and higher performance were divided into two groups: disadvantaged (DG) and benefited (BG). The performance and state-anxiety scores (IDATE), the two-way ANOVA and pairwise identified interaction between group and condition, and GP worst performing and most IDATE and GB with better performance and no change in IDATE provided with the audience. In the heart rate, there was no interaction but the main effect for the condition factor for both groups. It can be inferred that the audience influences the sensorymotor performance may cause worsening or improving depend on individual characteristics.

Abstract AIMSThe purpose of this study was to investigate how depressive symptoms mediate different motor control requirements in elderlies and to assess the concurring effects fomented by the interaction between aging and depressive symptoms, providing indirect measures of brain functionality. METHODS Sixty-eight elderlies were paired in terms of age and gender and were equally distributed into depressed and nondepressed groups, according to their score on the Beck Depression Questionnaire. The participants performed the Grooved Pegboard Test placing and withdrawing pegs while execution time and error rate were measured. RESULTS This investigation revealed that depressive symptoms exert a broad effect upon motor control, although that the symptom intensity, as well as the interaction between aging and depression intensity, were exclusively correlated with withdrawal task, suggesting that there is a greater effect upon motor acts with higher frontal lobe requirements. CONCLUSION The discrimination of motor control aspects provides a valuable contribution for the understanding of the underlying neurophysiology of the interaction between aging and depression as it represents an indirect measure of cerebral dysfunction. Further, these findings may still have clinical implications, as they can promote more rational approaches to the elaboration of preventive measures that help maintain the functional capability of depressed elderlies.

Abstract AIMS The purpose of this study was to investigate the effects of the combination of constant and variable practice when both, motor program and parameters on absolute and relative dimensions of a task, are manipulated. METHOD Twenty undergraduate students, aged between 19 and 24 years, participated in this study. Two groups practiced the task of pressing four keys of a numeric keyboard with total and relative times specified under constant conditions in the first part of the acquisition phase and under block conditions in the second part when one group varied parameters and another varied motor programs. RESULTS Both groups improved parameters and motor program measures during the acquisition phase. In the retention test, the parameters variation resulted in higher accuracy on motor program measure that the variation of motor programs. CONCLUSION Both combinations improve parameters and motor program accuracy. Moreover, the maintenance of GMP during the variation phase contributes to strengthening it.

RESUMO O objetivo foi avaliar os efeitos da estimulação transcraniana por corrente contínua (ETCC) sobre o córtex motor primário (M1) nas assimetrias de desempenho manual em uma tarefa de destreza manual. A amostra foi composta por 28 voluntários, destros, do sexo masculino e sem comprometimento neurológico. A tarefa (Grooved Pegboard) consistiu em encaixar 25 pinos em 25 receptáculos, o mais rápido possível. A tarefa foi executada no pré-teste com ambas as mãos para definição do nível de assimetria manual. Uma semana após o pré-teste foi aplicado a ETCC ou placebo, em seguida os sujeitos foram avaliados no pós-teste. Os resultados revelaram que os efeitos da ETCC no M1 não foram capazes de diminuir as assimetrias manuais em uma tarefa de destreza manual em sujeitos destros. Entretanto, somente o grupo ETCC melhorou o desempenho do pré-teste para o pós-teste (p<0,05) em ambas as mãos. A estimulação do M1 direito pode ter gerado benefícios no M1 contralateral.

ABSTRACT The aim of this study was to evaluate the effect of transcranial direct-current stimulation (tDCS) on the primary motor cortex (M1) in the manual performance asymmetries in a manual dexterity tasks. The sample consisted of 28 volunteers, right-handed, men and without neurological impairment. The task (Grooved Pegboard) consisted of inserting 25 pins in 25 receptacles, as soon as possible. The task was executed in the pretest with both hands to define the level of manual asymmetry. tDCS or Sham were applied a week after the pretest, then the subjects were evaluated in the post-test. The results revealed that the effects of tDCS in M1 did not reduce asymmetries in a manual dexterity task. However, only the tDCS group improved the performance from pretest to the posttest (p <0.05) in both hands. Stimulation of the right M1 may have generated benefits in the contralateral M1.

Abstract AIMS This study aimed to investigate the comparison between sex and manual aiming control in different cognitive and motor constraints of the task. METHODS Eighty-four right-handed participants (42 women) performed 110 trials of a manual aiming task with a non-inking pen on a digitizing tablet. The aiming task required four different conditions of execution. The control condition appeared on the computer screen in 70% of the trials, and the other three conditions, (a) distractor, (b) inhibition of response and (c) higher index of difficulty, each appeared in 10% of the trials. RESULTS Compared with women, men produced shorter movement and response times, as well as higher peak velocity in the control and distractor conditions. When the index of difficulty of the task increased, men produced only higher peak velocity. Women produced more corrective movements to achieve the target only in the control condition. CONCLUSION Our results corroborate those of previous studies that indicate sex-specific response strategies when the sensory motor system is challenged by different task constraints.