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The purpose of the present study was to investigate Effect of self-regulation from biofeedback exercises on the learning of dart throwing skill under pressure conditions. Participants were 28 undergraduate male students of the University of Tehran who were selected in an accessible manner as they were right-handed and had no experience in dart throwing and working with biofeedback devices. These numbers were randomly divided into four groups of visual, auditory, combined and control biofeedback. The number of biofeedback training sessions was 4 sessions with pre-test, post-test and retention sessions in 4 weeks. The results of analysis of covariance and mixed analysis of variance with repeated measures showed that visual, auditory and combined biofeedback training had a significant effect on the learning of dart throwing skills under pressure (P <0/05). According to the research findings, it is suggested to use biofeedback of temperature and galvanic response of the skin, visually, audibly or in combination, to learn darts throwing skills and skills similar to and close to darts throwing skills, as well as feedback of biofeedback sessions. Prioritize the combination biofeedback to see the best results.

 

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The aim of present study was to determine the effect of different levels of balance task difficulty and muscle pattern sonification on balance elderlies. eleve  healthy elderly mean age 66/09± 2/26 yr were selected voluntarily. The study inclusion criteria included no structural postural problems, lack of lower extremity fractures over the past six months, no uncorrected visual impairments, no vestibular disorders, and no use of nerve medications, narcotics, alcohol, and any substance leading to dizziness or lack of focus and affecting balance
 Participants were asked to stand still on a stable platform under two conditions (with sonification of muscle activity pattern and without feedback) in three difficulty levels (6, 8, and 10). Stability index scores (Overall, Anterior- Posterior and Medial- Lateral) were calculated by Biodex Balance System.  The duration of each test was 20 seconds and rest times were 10 seconds. Results showed that with increasing task difficulty, scores of  overall balance ,Medial- Lateral balance  and Anterior- Posterior balance. In addition, There was a significant reduction in the scores of Overall balance (p= 0/005), anterior - posterior balance (p= 0/002) and medial - lateral balance (p= 0/022) and sonification of muscle activity pattern condition compared with without sonification of muscle activity pattern condition in the level of 6. Overall, the results of this study showed that increasing task difficulty increases postural sway, and the availability of sonification of muscle activity pattern can improve balance and reduce postural sway.
Keywords: Electrical activity, Stability index, Biofeedback , Task Difficulty