نوع مقاله : مقاله پژوهشی
نویسندگان
1 کارشناسی‌ارشد رفتار حرکتی، گروه رفتار حرکتی، دانشگاه سمنان، سمنان، ایران
2 دانشیار رفتار حرکتی، گروه رفتار حرکتی، دانشگاه سمنان، سمنان، ایران
3 استادیار رفتار حرکتی دانشکده علوم ورزشی دانشگاه مازندران بابلسر، ایران
کلیدواژه‌ها
موضوعات
عنوان مقاله English
نویسندگان English
Background and Purpose
Visual impairment, as a sensory disability, accounts for approximately one-third of global disability statistics. Balance is a critical component of the sensorimotor system essential for maintaining postural stability. Individuals with visual impairments often exhibit deficits in postural control and balance, which compromise automatic motor control. To compensate, they rely heavily on auditory cues to enhance stability and spatial orientation. Recent interventions have explored the use of rhythmic auditory stimulation (RAS), which utilizes external attentional focus to improve motor performance. The effectiveness of RAS may be attributed to its ability to direct external attention, as individuals with visual impairments often depend on internal attentional focus and conscious processing during movement rather than automatic motor control. This study examined the effects of a gait training program incorporating rhythmic auditory stimulation on static and dynamic balance in individuals with congenital blindness.
Methods and Materials
This quasi-experimental study involved 20 congenitally blind participants (9 females and 11 males) selected through convenience sampling. Written informed consent was obtained from all participants and their guardians, with assurances of confidentiality and exclusive research use of the data. Balance was measured using a foot scan device that recorded the coordinates of the center of pressure (COP) of the feet. For static balance assessment, participants stood barefoot on the device for 20 seconds, facing forward. Dynamic balance was evaluated using the stability limit test, where participants stood barefoot on the device and tilted their bodies maximally in four directions—forward, backward, left, and right—without lifting their feet off the surface, for 20 seconds. After pre-test measurements, participants were randomly assigned to experimental and control groups. The experimental group performed individualized gait training with rhythmic auditory stimulation under trainer supervision. Post-test measurements were conducted similarly. COP data were extracted using Balance software and analyzed in Excel. Statistical analysis employed parametric covariance tests, or non-parametric bootstrap tests when assumptions were violated, with significance set at p ≤ 0.05, using SPSS version 21.
Results
Descriptive data showed that the COP level and COP distance (static balance indices) and COP amplitude in the anterior-posterior and medial-lateral directions (dynamic balance indices) increased in the experimental group relative to controls. Tests for normality indicated non-normal distributions for COP level and distance (p < 0.05), necessitating bootstrap analysis for these variables. Bootstrap results showed no significant changes in COP level (p = 0.629) and COP distance (p = 0.613) following the intervention. Covariance analysis revealed that training with external focus instructions did not significantly affect dynamic balance indices, including COP amplitude in the anterior-posterior (p = 0.063) and medial-lateral (p = 0.428) directions.
Discussion
Although the intervention did not yield statistically significant improvements in static balance, the observed positive trends in COP level and distance suggest potential benefits that might become significant with longer training durations. Maintaining static balance resembles an inverted pendulum, where the body’s center of gravity is stabilized by relatively constant forces applied to the ground (17), making static balance less challenging to improve. The lack of significant effect on dynamic balance, despite relative improvements in the experimental group, suggests that external focus instructions may have a greater impact on dynamic than static balance in blind individuals. External focus facilitates automatic motor processes and better self-organization of sensorimotor systems, reducing reliance on higher neural centers for limb control and enhancing motor performance (7). Since visually impaired individuals tend to focus on internal information, auditory external feedback may provide critical supplementary cues during balance tasks.
Conclusion
While the intervention did not produce statistically significant improvements, the trends observed indicate that rhythmic auditory stimulation may be a viable, low-cost rehabilitation tool for enhancing postural stability and reducing fall risk in individuals with visual impairment. Its accessibility and ease of implementation make it suitable for clinical and community settings. Further research with larger sample sizes, extended intervention periods, and gender-specific analyses is needed to confirm these findings and optimize training protocols.
Article Message
New rehabilitation methods such as rhythmic auditory stimulation show potential to improve static and dynamic balance in individuals with blindness. However, given the lack of statistically significant results, cautious application is recommended, and further research is essential to establish efficacy.
کلیدواژه‌ها English
