Yoshio Kitajima

Relationship between motor skill and social impairment in children with autism spectrum disorders

Abstract Aim: The purpose of this study was to investigate the relationship between motor skill and social impairment in children with autism spectrum disorders (ASD). Methods: The subjects were 26 children with ASD aged 7–16 years. Their intelligence quotients (IQ) ranged from 73 to 124. We conducted two tasks: movement assessment battery for children-2 (MABC-2) and social responsiveness scale (SRS). The MABC-2 is a motor test that can assess total motor ability, and three sub-domain abilities. SRS is a parent questionnaire that can assess individual differences in social impairment. Results: In the children with ASD in this study, difficulty with manual dexterity was the most frequently occurring problem. Also, their individual differences in social impairment were strongly interrelated with problems with manual dexterity. Interpretation: These results suggest that when MABC-2 is administered to children with ASD but without severe cognitive impairment, due attention should be paid to their manual dexterity (MD) score.

Motor Skills and Social Impairments in Children With Autism Spectrum Disorders

The purpose of this study was to examine the relationship between the Japanese version of the Developmental Coordination Disorder Questionnaire (DCDQ-J) and the Social Responsiveness Scale (SRS) in Japanese children with autism spectrum disorders (ASD). The participants were 19 children with ASD. The DCDQ-J is a parent questionnaire that can assess the degree of motor skill impairments, and the SRS assesses the severity of social impairments. To check the criterion-related validity of the DCDQ-J in children with ASD, the Japanese version of the Movement Assessment Battery for Children-2 (MABC2-J) was also conducted. The total score of the DCDQ-J was significantly negatively correlated with the SRS score in the same way as the MABC2-J total score. These results indicate that the severity of social impairments in children with ASD is related not only to the child’s fundamental motor abilities but also to practical motor skills in everyday life.

Development of carefulness and quickness observed for a tray-carrying task.

The purpose of this study was to investigate the developmental change in performance of groups of children instructed to behave carefully and quickly in a tray-carrying task. The subjects were 69 nonhandicapped children from a kindergarten, ages 3–4 to 6 years, and 20 adult students who volunteered. Subjects were instructed to carry as fast as they could a tray with a glass of water for 3 m without a spill. The amounts of water spilled and the times taken were measured. The amounts of water spilled were hardly different within groups of children of the same ages or between age groups. But the times were different among groups: the younger ones took longer, and the difference in time between tray-carrying and normal walking was greatest for the youngest group. Children could carry the tray as carefully as adults but could not do so quickly. The nature of the representation of the instruction in relation to the behavior of children and the difference in strategy to guarantee carefulness between children and the adults are discussed.

Speed and accuracy of motor and cognitive control in children with intellectual disabilities

Abstract Objectives: The purpose of this study was to investigate the relationship between motor and cognitive control in children with intellectual disabilities (ID), focusing on the two aspects of speed and accuracy. Methods: The subjects were 39 children with ID aged 8–15 years. Their Intelligence Quotient (IQ) ranged from 13 to 71. The children with ID included 12 children with Down’s syndrome and 10 children with autism. We conducted three tasks: seal affixation task, tray-carrying task, and the Matching Familiar Figures Test (MFFT). The seal affixation and tray-carrying tasks are motor tasks we devised that can separately measure the speed and accuracy of motor control. MFFT is a cognitive control task that can be used to evaluate cognitive styles, such as impulsive-reflective. Results: In the children with ID in this study, motor speed and accuracy were related to cognitive speed and accuracy. Moreover, these children could be classified into four groups based on their MFFT performance, with the motor performances of each group corresponding to the characteristics of that group seen on MFFT. Discussion: These results suggest the possibility that a motor-cognitive control link exists in children with ID.

Verbal regulation of grip force in preschoolers.

The purpose of this study was to clarify the developmental processes in verbal regulation by preschool children. Participants were 152 typically developing children (74 boys, 78 girls) between 4 and 6 years of age (M = 5.3, SD =.8), and 30 healthy adults (15 men, 15 women) between 19 and 26 years of age (M = 20.8, SD = 1.4). In Exp. 1, the task was to regulate grip force based on quantitative instruction which implies using a scale for regulation. Participants were required to produce a half-grip force of the maximum (Task 1). In Exp. 2, the task was grip-force regulation based on nonquantitative instruction. The participants were asked to respond with a slightly weaker grip force than the maximum (Task 2) and then a further weaker grip force (Task 3) than that used on Task 2. The regulation rates produced the extent of regulation and suggest regulation by quantitative instruction may develop earlier than by nonquantitative instruction. Also, precise grip-force regulation based on the semantic aspect of instruction may be difficult for young children. The developmental changes in the rate of performance especially observed in children of 4 to 6 years indicate that the tendency to use too much grip force disappears during this preschool period. In addition, too little grip force in regulation may reflect the developmental process toward fine grasping movements.

Discrepancy between Motor and Cognitive Control in Adults with Intellectual Disabilities

Purpose : To investigate the relationship between motor and cognitive control in adults with intellectual disabilities (ID), focusing on two aspects, speed and accuracy. Method : Participants were 62 adults with ID aged 20 to 47 years. Their intelligence quotients (IQ) ranged from 13 to 61. Nine of the adults with ID had Down syndrome, and 8 of the adults had autism. We conducted three tasks: seal affixation task, tray-carrying task, and the Matching Familiar Figures Test (MFFT). The seal affixation and tray-carrying tasks are motor tasks we devised that can separately measure the speed and accuracy of motor control. MFFT is a cognitive control task that can be used to evaluate cognitive styles, such as impulsive-reflective. Results : Adults with ID showed high motor accuracy and similar motor speed regardless of their MFFT performance. That is, discrepancies between motor and cognitive control existed in adults with ID. Conclusions : The results of this study indicate that some types of motor control problem may become unclear with growth. A longitudinal investigation focused on the motor skill development of persons with ID is therefore necessary.