كليدواژه :
تحريك الكتريكي مغز , سالمند , كنترل پاسچر , مخچه
چكيده فارسي :
زمينه و هدف: كاهش مهارت‌هاي تعادل و كنترل پاسچر از عوامل كليدي زمين‌خوردن سالمندان است. مطالعهٔ حاضر با هدف بررسي تأثير تحريك الكتريكي مخچه با جريان مستقيم بر متغيرهاي كينتيك كنترل پاسچر اين افراد انجام شد.
روش‌بررسي: اين پژوهش نيمه‌تجربي و از نوع پيش‌آزمون‌پس‌آزمون بود. جامعهٔ آماري را تمامي سالمندان مراجعه‌كننده به مركز جامع توان‌بخشي جمعيت هلال‌احمر شهر تهران تشكيل دادند كه از بين آن‌ها تعداد بيست نفر سالمند 60الي75ساله از هر دو جنس زن و مرد با نمونه‌گيري دردسترس و هدف‌مند انتخاب شدند. سپس به‌صورت تصادفي در دو گروه ده‌نفري تجربي و كنترل قرار گرفتند. بعد از اندازه‌گيري اوليهٔ متغيرهاي كينتيك كنترل پاسچر توسط دستگاه پاسچروگرافي، مخچهٔ شركت‌كنندگان هر دو گروه تجربي و كنترل در پنج جلسهٔ بيست‌دقيقه‌اي با جريان مستقيم الكتريكي دو ميلي‌آمپري واقعي و غيرواقعي (شم) تحريك شد. در هر جلسه، بلافاصله پس از تحريك، آزمودني‌ها به‌مدت نيم‌ساعت تمرينات تعادلي روي دستگاه هوبر انجام دادند. پس از اتمام پنج جلسه، متغيرهاي كينتيك كنترل پاسچر با دستگاه پاسچروگرافي مجدداً اندازه‌گيري شد. جهت تجزيه‌وتحليل داده‌ها آزمون شاپيروويلك، آزمون لون، همگني شيب خط رگرسيون و آزمون تحليل كوواريانس به‌كار رفت.
يافته‌ها: نتايج تحقيق، حاكي‌از تأثير معنادار تحريك الكتريكي مخچه با جريان مستقيم بر متغيرهاي سرعت جابه‌جايي مركز فشار (0٫020=p)، دامنهٔ جابه‌جايي مركز فشار (0٫037=p)، استراتژي كنترل پاسچر (0٫042=p) و تعادل مركب (0٫018=p) سالمندان در گروه تجربي است.
نتيجه‌گيري: تحريك الكتريكي مخچه با جريان مستقيم الكتريكي بر متغيرهاي كينتيك كنترل پاسچر و تعادل سالمندان اثرات سودمندي دارد.
چكيده لاتين :
Background & Objective: Loss of balance and falling is one of the health problems in the elderly people who causes a change in their quality
of life. Reducing balance and postural control skills is one of the key factors in the aging of the elderly. The aim of the present study was to
investigate the effect of cerebellar transcranial direct current stimulation on kinetic variables of postural control and balance of elderly people.
Methods: This study was a quasi–experimental, pre– and posttest design. Participants of this study included 20 elderlies (60–75 year–old) of
both genders who referred to the Tehran Rehabilitation Center of Red Crescent Society in the summer of 2017. They were selected based on
inclusion and exclusion criteria and available and targeted sampling method, and randomly assigned to two “Intervention” (real) and “control”
(Placebo) groups. Participants had criteria witch is needed to use transcranial direct current stimulation (TDCS), computerized dynamic
posturorghraphy and Huber apparatus based on safety screening questionnaire for TDCS & TACS (transcranial direct current stimulation &
transcranial direct alternating stimulation) and gained score cognitively over 23 in mini mental status evaluation (MMSE). The subject's exclusion
criteria from the research included these cases: having acute cerebrovascular diseases such as epilepsy, which increases risk of stimulation, acute
eczema of the skin, the presence of any metal implants in the brain, having a history of imbalance and frequent dizziness, and fear of electrical
stimulation of the brain. After a preliminary assessment of kinetic postural parameters by computerized dynamic posturorghraphy apparatus,
intervention group received direct current stimulation over the cerebellum at 2mA and placebo group received sham stimulation, twenty minutes
in five sessions. Based on the protocol that used in this study, the anode electrode was placed 2 cm below the occipital inion and the cathode
electrode on the right buccinators muscle. At each session, immediately after stimulation, participants performed half–hour equilibrium exercises
on the Huber apparatus. After completing five sessions, the kinetic variables of postural control were re–measured by the posturorghraphy
apparatus. The computerized dynamic posturorghraphy apparatus was the equitest model of the American NeuroCom company, one of the most
advanced kinetic variables assessor apparatus that are used to manipulate effective sensory systems in control posture. This device has a unique
evaluation technique that provides quantitative data in posture control and it is a suitable tool for analyzing age–related changes, TDCS device
was an ActivaTek Attenda Inc model. The Huber device was the Valence Cedex 09 model, which was used to improve neuromuscular
coordination, muscle strength and body posture correction, Sensory integration and motor control improvement.
Results: In analyzing the results, Shapiro–Wilk test was used to evaluate the normal distribution of data and Levene's test for equality of error
variances between the groups, and after checking the homogeneity of slope regression, covariance analysis was used to determine the difference
between the post test scores of intervention and control groups. The results of the study indicated that cerebellar transcranial direct current
stimulation had a significant effect on the center of pressure velocity (p=0.020), the center of pressure distance (p=0.037), postural control
strategy (p=0.042) and equilibrium composite (p=0.018) on the elderly participants of the experimental group.
Conclusion: The results of this study showed that cerebellar TDCS has beneficial effects on kinetic variables of postural control and balance of
elderly people. This can be a good opportunity to promote healthy for the elderly and to develop therapeutic approaches for elderly people with
equilibrium disorders. The field of transcranial direct current stimulation and neural rehabilitation are experiencing a new phase with the advent
of the cerebellum TDCS. This new knowledge can be useful in understanding the interactions between the cerebral cortex and deep cerebellar
nuclei.
