Abstract

Background and Aim: The Action Observation stimulates mirror neurons. It is the effective acquisition of skills, motor learning and memory formation and this feature can be used to treat injuries such as stroke. The aim of this study was to investigate the effect of action observation on the symmetry of weight distribution in lower limbs and stability indices in semi-dynamic stability.

Materials and Methods: This study was conducted in 91 healthy male and female non-athletes aged 20 to 45 years. Data were collected through questionnaires and clinical examinations. Subjects were randomly assigned to men and women with and without film observation. A 3-minute short film was preapared to stimulate mirror neurons in the standing position on the symmetry weight measurement system and Biodex platform system. In film observation group, before and after viewing the film, distribution of weigh bearing on the right and left sides, and dynamic stability indices in two stability levels of 5 and 8 were measured and calculated indices of total, anterior - posterior and medio- lateral indices were obtained. In without film observation group, measurements were performed at the similar time as a film observation group.

Results: Percentage weight distribution showed no significant difference between the two groups. The comparison of percentage changes between two groups showed that observation of the film improved significantly total index (p <0.002) and anterior – posterior index (p <0.018) in the stability level of 5. Analysis of the results in the separately men and women groups, showed the significant improvement of these parameters only in women group after film observation regardless of film observation, the percentage changes of stability indices showed no significant differences in men groups.

Conclusion: Action Observation (by activating the mirror neurons) can be effective methods to improve the balance standing of healthy people on the stable and unstable surfaces. Significant improvement stability indices in women after viewing the film, may suggest the greater sensitivity of women's mirror neurons related to men.

Keywords: Mirror Neurons, Action Observation, Symmetry of Weight Distribution, Dynamic Stability, Stability

Background and Aim : Trauma or micro-trauma over prolonged period of time can lead to

  pathoanatomical changes and passive instability of the sacroiliac joint. These subjects often reluctant to bear full weight through the impaired side of the pelvis. The aim of this study was to investigate the effect of exercise therapy on symmetric distribution of weight in sacroiliac joint instability in standing and walking through Alfoot device.

Materials and Methods : In this study, 17 subjects with sacroiliac joint instability with age range of 20-40 years were selected by simple sampling. Subjects performed a single session of training that involve five tasks in 3 sets, including sitting on gym ball, lying on gym ball, quadruped, standing near wall and standing on tilt board. Before, immediately after, 5 and 10 minutes after intervention , scanning the both feet were recorded during standing and walking.

Results : The amount of weight on both feet in bipedal stance position were significantly different before and immediately after the intervention. But this difference , 5 minutes (p =0.058) and 10 minutes (p =0.110) was not significantly different after exercise therapy. The pressure on the middle part of the foot during walking significantly increased immediately after the intervention and it continues up to 10 minutes .

Conclusion : The results of this study suggest that training of lumbopelvic muscles can be an effective way to improve weight distribution on the affected side in patients with sacroiliac joint instability .