نشریه رفتار حرکتی
پیاپی 53 (پاییز 1402)

Attention Deficit Hyperactivity Disorder is one of the most common childhood disorders that has attracted the attention of psychologists and psychiatrists. The main features of this disorder include: inability to control motor behavior, learning deficits, aggression, academic problems, sedation, and motor dysfunction. The purpose of this study was to investigate the effect of visual perception training on depth perception in children with attention deficit hyperactivity disorder. The research method was applied in terms of purpose and in terms of nature and method of quasi-experimental post-test with control group. For this purpose, 5 boy children referred to the clinic in the age range of 6 to 12 years were selected and available based on research objectives, Rats were randomly divided into two groups. The findings of this study showed that a period of visual perception training had a significant effect on reducing the symptoms of ADHD. The covariance analysis test was used to find the differences between the groups. The results showed that there was a significant difference in attention deficit hyperactivity disorder in comparison with the control group in reducing attention deficit hyperactivity disorder (P≤0/05). Based on the findings of the present study, it can be concluded that visual perception training can be a useful method in reducing symptoms of ADHD or at least one of these methods and in combination with other methods used in the treatment of ADHD children.

The purpose of the present study was to investigate the effect of visual occlusion training on the performance of forehand drive skill. Participants included 48 students (24.06 ±3.78 yrs.) who were divided into four groups: central vision, peripheral vision,, complete vision and control. The study consisted of three stages: pre-test, immediate and delayed retention tests. After the pre-test phase (30 trails), the participants of the experimental groups practiced the forehand drive in table tennis for eight sessions and five blocks of 100 trails in each session. At the end of the acquisition stage, the immediate retention test was performed and after two weeks, the retention test was performed with the same of the pre-test. The results of the immediately retention test showed that forehand skill was significantly improved in all three experimental groups compared to the control group (p≤0.05). Likewise, at this stage, the peripheral vision group showed the most progress. In the delayed retention test phase, the performance of the full vision and peripheral vision groups was better than the control and central vision groups, and the central vision group had a similar performance to the control group. Generally, according to the findings, considering the better performance of the peripheral vision group in the immediate and delayed retention tests compared to the control and central vision groups, It can be concluded that training with central vision occlusion is probably a type of training that improves performance in forehand drive in table tennis skill.

Combining self-controlled and imposed levels of task difficulty during training seems to be better than completely self-controlled conditions. This study aimed at determining whether self-control of task difficulty affects skill learning during the early and late practice stages. For this purpose, 48 novice of high school students with a mean age (17.5 ± 1.75) years were randomly divided into four groups including complete self-controlled, self-controlled at the early, self-controlled at the end and paired. In the acquisition phase, which includes 100 trails,the self-control group was informed that they could choose and practice any of the preset distances from the target (1/5, 3, 3/5, 4, 4/5, 5 m) before each trial during the acquisition phase. The task difficulty was either self-controlled or imposed to the participants in the two phases of the acquisition session. The accuracy score of basketball throwing were analyzed by mixed variance analysis with repeated measures in acquisition and retention and transfer tests. The results showed that self-control of task difficulty improves the compared to the paired group (P=0. 001). Secondly, the performance of self-control of task difficulty in the early practice group was better than self-control of task difficulty in the end practice group (P=0. 001). Third, accuracy in the self-control of task difficulty in the early practice group was significantly better than self-control difficulty group and the paired group (P=0. 001). In general, the benefits of self-control of task difficulty were justified using the challenge point framework, the information processing perspective and cognitive perspective.

The aim of this study was to examine the separate and combined effects of the external focus of attention and autonomy support on learning a targeting task, according to OPTIMAL theory of motor learning. 60 female students were randomly assigned into 4 groups of 15 participants in each group including external focus - autonomy support (provided a choice about the place of throwing along with a focus on target); external focus (focus on target); autonomy support (provided a choice about the location of throwing); and a control (without attentional instruction). The research motor task was a controlling throw of a coin with a dominant hand on targets placed on the ground consisting of ten concentric circles. Participants in a 2 * 2 design, (focus externally: Yes/No) (autonomy-support: Yes/No) completed the acquisition phase consisting of 60 trials. Retention test using with 2 hours and 24 hours' delay, were performed. The analysis of variance revealed that the main effect of external focus (p=0.38) and the interaction effects of external focus and autonomy support (p=0.69) are not significant. The main effect of autonomy support is significant (p=0.002). Participants in autonomy support groups performed better than those without autonomy support in retention phase. Overall, these findings suggest that the autonomy support separately and without the combination of external focus affects the learning of a targeting motor skill.

The purpose of the present study is to evaluating the role of kinematic factors in predicting the motor performance of gymnastic children aged 10-12 years by examining the effect of choking under pressure. The statistical sample of the research consisted of 40 skilled female gymnasts with an age range of 10-12 years, who were selected as available and their motor performance (execution of a chain of gymnastic floor movements) after evaluating some kinematic factors (motion range and sense joint position) was measured and evaluated in low-pressure and high-pressure conditions by two referees and a gymnastics coach. Data analysis was done using descriptive statistics (mean and standard deviation) and inferential (linear regression) methods in SPSS software. The results of the research showed that kinematic factors in conditions of high pressure can predict the motor performance of gymnasts. Therefore, it can be concluded that kinematic factors may play a significant role in predicting the motor performance of gymnasts under psychological pressure and change it.

falling and losing balance is one the most Important problem in elderly. Exercise interventions are one the best approach to resolve this problem. Task constraints manipulation is one this approach seems it can improve balance indexes in elderly population. So the aim of current study is to investigate effect of task constraints manipulation on balance indexes of healthy elderly adults Thirty elderly people were selected to participate in the research, and they were randomly divided into control and intervention groups. The intervention group participated in task constraints manipulation exercises for 8 weeks (3 times per week), while the control group lived without any interventions. The balance indexes were evaluated using the Biodex system. The results showed task constraints manipulation exercises improve the balance indexes in intervention group. The result of ANCOVA test revealed a significant improvement in the scores of postural control and balance (P<0.05). The results of this research confirm the effect of task constraints manipulation exercises on improving balance indexes in the elderly. Balance improvement finally can lead to reduce the fall risk in elder population.

Today, although virtual reality is suggested as a suitable and exciting alternative to other training methods, but all aspects of its effectiveness in combination with other interventions have not yet been well clarified. Therefore, our aim was to determine the effect of virtual reality with and without transcranial direct current stimulation on balance performance. The participants in the research were 36 sedentary adolescent girls who were purposefully selected and voluntarily participated in this study. The subjects were randomly divided into three control groups (12 people), VR+a-tDCS (12 people) and VR+sh-tDCS (12 people). First, each group received brain stimulation (anodal or sham) for 20 minutes with an intensity of 2 MA, then they performed virtual reality exercises for one hour. The control group did not receive any intervention. Each group conducted 12 sessions (3 sessions per week) with one day in between. Y and STROK tests were used to evaluate balance. The statistical test of the analysis Two-way Mixed ANOVA was used at the significance level of 0.05 and SPSS23 software. Static balance in the anodal group were higher than the sham group (p=0.004) and control group (p=0.001). Also, the dynamic balance in the anodal group was higher than the sham group (p=0.013) and the control group (p<0.001). The findings showed that anodal stimulation can increase the effectiveness of virtual exercises more and more lastingly. And this difference was maintained in the retention stage so that performance of the VR+a-tDCS group was superior to the other two groups.