Abstract:
چکیده:
مقدمه:
ادراک زمان مقوله ای پیچیده است، که کنجکاوی هوشمندانه ی بشر را برای دستکاری علمی و شناخت آن به راه می اندازد. این مطالعه با هدف بررسی اثرات ذهن آگاهی بر ادراک زمان و امواج مغزی با به کار بردن تکلیف دوقستی زمانی و ثبت امواج مغزی به طور همزمان با روش آزمایشی گروهی انجام شد. ذهن اگاهی برگرفته از فایلهای صوتی تمرینات ذهنآگاهی ویلیامز و پنمن بود.
روش کار:
این تحقیق با روش آزمایشی با گروه کنترل و اندازهگیری قبل و بعد از ارایهی متغیر مستقل انجام شد. این مطالعه از پاییز 1397 تا 1399 به طول انجامید. محل اجرای پژوهش دفتر کار خصوصی پژوهشگر بود. نمونه گیری از میان 143 نفر از دانشجویان دانشگاه علوم تحقیقات، به طور تصادفی انجام شد. از این میان 31 نفر دانشجوی لیسانس که از نظر سلامت روانی و بیماریهای مغزی توسط مصاحبهی بالینی ساختار یافته برای اختلالهای روانپزشکی DSM-5 (SCID-5-CV) ارزیابی شدند و از نظر توانمندی ذهن آگاهی متوسط بودند به دو گروه آزمایش 16 و کنترل 15 نفر تقسیم شدند. برای گروه آزمایشی فایل صوتی 13 دقیقهای ذهن آگاهی و کنترل فایل صوتی خنثی ارائه شد. تکلیف دو قسمتی زمان و ثبت توسط دستگاه آمپلی فایر mitsar 19 کاناله، و توان امواج مغزی در باندهای فرکانسی دلتا، تتا، آلفا، بتا و گاما قبل و بعد از ارائه متغیر مستقل در دو گروه در کانالهای C3، C4، Cz، F3، F4، Fz و Pz محاسبه شد تجزیه وتحلیل اماری با روش ANCOVA،MANCOVA و نرم افزر spssنسخه 24 انجام شد.
یافتهها:
نتایج نشانگر افزایش توان بتا، دلتا و تتا در کانالهای مختلف بود. تغییرات توان آلفا به صورت متعارض به دست آمد. امواج گاما و اندازه شاخص تتا به بتا کاهش معناداری در گروه آزمایش داشتند. یافتههای رفتاری نشانگر افزایش تعداد پاسخهای طولانی (Persentage Long response) و کاهش نقطه دوقسمتی زمان (Bisection point) بود.
نتیجه گیری:
با توجه به یافتهها میتوان اینگونه استنباط کرد که متغیر ذهن آگاهی با تغییر در اندازههای الکتروفیزیولوژیک فوق که نشانگر کاهش برانگیختگی، افزایش تمرکز به درون، افزایش مهار حرکتی و افزایش آگاهی بدنی و تنظیم هیجانی است در فرآیند پردازش شناختی ادراک زمان مؤثر بوده و موجب بیش تخمینی در ادراک زمان میشود.
Introduction:
A recent study examined the effects of mindfulness on the perception of time and brain waves by a group experimental method.
Methods:
31 undergraduate students who were evaluated in terms of mental health and brain diseases and were moderate in terms of mindfulness ability were divided into two experimental groups of 16 and 15 controls. The temporal bisection task and recording brain waves was performed before and after the independent variable.
EEG signal processing was performed by forming a data matrix of EEG signals of individuals and display characteristics of task images and subjectschr('39') responses, separating the EEG signal of the desired channels for processing: F3, Fz, F4, C3, Cz, C4, Pz. In the preprocessing phase, remove the EMG and EOG motion artifacts and blink ICA when needed. Since the calculation of the frequency band power is considered, the desired frequency range was considered to be 0.5 to 45 Hz, this range does not include the noise of 50 Hz city electricity and DC artifact. Therefore, no frequency filter was used at this stage to preserve the original content of the EEG signals and to avoid signal degradation as much as possible. Delta power: 0.5 -4Hz, theta: 4-8Hz, alpha 8-12Hz, alpha 1: 8-10Hz, alpha 2: 10-12Hz, beta: 12-30Hz, beta 1: 12-16Hz, beta 2: 16-20 Hz, Beta 3: 20-30 Hz, Gamma 30-40 Hz, Gamma 1: 30-35 Hz, Gamma 2: 35-40 Hz. Calculated in C3, C4, Cz, F3, F4, Fz and Pz channels.
The reference segment 500 milliseconds before each trial was considered as the reference of that trial. The power values of the above frequency bands were extracted for all individuals for all selected channels and for before and after the intervention. The power output stored in the content was extracted in mat format. Which included the relevant channel number, for example C3, and was recorded before or after the intervention. The power of each frequency band is as follows: Absolute power, normalized power, ie absolute power minus reference power divided by reference power (which indicates the percentage increase in power from reference to trial).
One session of mindfulness audio file was presented for the experimental group and one session of neutral audio file was presented for the control group. The results were analyzed by MANCOVA -ANCOVA test. A significant decrease in Bp and an increase in the percentage of Plongs were observed in the experimental group compared to the control.
Results:
Significant increase in beta in C3, C4, Cz, F3, F4 and Fz in the experimental group compared to control confirms the effect of mindfulness variable on beta change and improved time perception.
There was also a significant increase in delta power at F3, Fz and Pz and theta power at C4, F4 and Fz in favor of the experimental group. Alpha power changes were conflicting at C3 and F4. Significant increase in alpha power was observed in C4, Cz and Pz and decrease in F3 and Fz. Thus, despite the effect of a relative decrease in arousal level with increasing alpha, it can be inferred that in order to achieve integrated results on the alpha effect, a more specific study is needed to distinguish alpha changes in the hemisphere.
The mindfulness variable significantly reduced gamma power at C3, Cz, F3, F4 and Fz. As a result, it can be hypothesized that mindfulness may also improve temporal performance by increasing motor inhibition.
A significant increase in theta/ beta at C4, Cz and Pz indicates a decrease in external concentration and an increase in internal concentration. According to the above results, it can be inferred that the mindfulness variable has significantly increased the theta-to-beta index in C4, Cz and Pz channels.
Conclusion:
According to the results of this study, mindfulness overestimates time by decreasing arousal and increasing attention to internal stimuli and increasing motor inhibition. This effect occurs by increasing the power of beta, delta, theta and decreasing gamma, which are possible mediators in this process, and based on the conflicting results of alpha, a more specific study of alpha changes in the hemisphere is proposed.
Ethical consent form approved by Tabriz University was taken from all subjects and the form was sent to the appendix. The Faculty of Educational Sciences and Psychology of Tabriz University does not currently provide an ethical code-based identifier for research.