Advances in Cognitive Sciences

fa اثربخشی مراقبه ذهن‌آگاهی بر ادراک زمان و امواج مغزی با کاربرد تکلیف دوقسمتی زمانی در جمعیت دانشجویی The effectiveness of mindfulness meditation on the time perception and brain waves using a temporal bisection task in the student population علوم اعصاب شناختی پژوهشي اصیل Research مقدمه: ادراک زمان مقولهای است که کنجکاوی هوشمندانه بشر را برای دستکاری علمی و شناخت به راه میاندازد. این مطالعه با هدف بررسی اثرات ذهنآگاهی بر ادراک زمان و امواج مغزی با به کار بردن تکلیف دوقستی زمانی انجام شد. روش کار: این پژوهش با روش آزمایشی با گروه کنترل انجام شد و از پاییز 1397 تا 1399 به طول انجامید. نمونه‌گیری از 143 نفر از دانشجویان دانشگاه علوم تحقیقات، به شیوه تصادفی انجام شد. 31 دانشجوی کارشناسی از نظر سلامت روانی و بیماری‌های مغزی توسط مصاحبه بالینی ساختاریافته (SCID-5-CV) ارزیابی شدند. توانمندی ذهن‌آگاهی‌شان بر مبنای پرسشنامه ذهن‌آگاهی Freiburg در حد متوسط بود، به دو گروه آزمایش 16 نفر و کنترل 15 نفر تقسیم شدند. برای گروه آزمایشی فایل صوتی 13 دقیقه‌ای ذهن‌آگاهی و کنترل فایل خنثی ارائه شد. تکلیف دو قسمتی زمان و ثبت توسط دستگاه آمپلی‌فایر Mitsar 19 کاناله، و توان امواج مغزی در باندهای فرکانسی مختلف قبل و بعد از ارائه متغیر مستقل در دو گروه در کانال‌های C3، C4، Cz، F3، F4، Fz و Pz محاسبه شد. یافته‌ها: نتایج نشانگر افزایش بتا، دلتا و تتا در کانال‌های مختلف بود. تغییرات آلفا به صورت متعارض به دست آمد. گاما و اندازه تتا به بتا کاهش معناداری در گروه آزمایش داشتند. یافته‌های رفتاری نشانگر افزایش تعداد پاسخ‌های طولانی (Percentage long response) و کاهش نقطه دوقسمتی زمان (Bisection point) بود. نتیجهگیری: نتایج نشان داد که متغیر ذهن‌آگاهی 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. <div id="_com_1" uage="JavaScript"></div> <div><div></div></div> Introduction Time Perception is a category that stimulates human's intelligent curiosity for scientific manipulation and cognition. Differences in cognitive function of time perception in different areas such as time awareness, time perspective, and time estimation concerning different variables such as age, different emotional and mental states, different personality traits, and different psychiatric disorders have been studied. In this regard, the relationship between altered states of consciousness and time perception is one of the essential and new areas of attention. In this area, the altered states of consciousness due to meditation exercises have attracted a lot of attention. The mindfulness technique is one of the meditation techniques that affect human cognitive function, including time perception. The studies that have been done in this field are primarily in the field of cognitive, behavioral, and perceptual. However, very little research has been done on the electrophysiological mechanisms of the effect of mindfulness on the time perception. This study aimed to investigate the effects of mindfulness on the time perception and brain waves using a bio section task with a controlled group experimental design. Methods This research was carried out through a randomized controlled clinical trial, which was lasted from autumn 2018 to 2020. 143 students of the Science and Research Branch of Islamic Azad University participated voluntarily in the experiments. In a structured clinical interview for the DSM-5 (SCID-5-CV) psychiatric disorder, thirty-one undergraduate students were assessed for mental health and brain disease.. Their mindfulness ability was moderate based on the Freiburg questionnaire, and they were assigned randomly into experimental and control groups, containing sixteen and fifteen participants, respectively. The experimental and control groups were presented a 13-minute mindfulness audio file and a neutral file to. 19-channel EEG signals during the temporal bio section task was recorded from participants, while the power of brain waves in different frequency bands were calculated before and after presenting the independent variable in two groups in channels C3, C4, Cz, F3, F4, Fz, and Pz. F3, Fz, F4, F3, C3, Cz, C4, and Pz channel signals from 19 channels, in 7 conditions, and two pre-test and post-test stages were used for analysis. ICA removed the EMG and EOG artifacts and blinking. Spectral analyzes in the range of 0.5 to 40 Hz were considered. Finally, the signals were visually examined, and the artifact was removed using amplitude thresholding. The Welch power spectrum density estimation method performed power extraction, hamming window 400 ms, 50% overlap, and 0.25 Hz resolution. Frequency bands, Delta 0.5-4, Theta 4-8, Alpha 1: 8-10, Alpha 2: 10-12, Beta 12-30, Gamma 1: 30-35, and Gamma 2: 35-40 Hz were considered. Signal segments were defined from the start of the stimulus display to the response moment in each trial. 500 milliseconds before the trial, and the reference interval was considered. The normalized power was calculated from the relation (signal segment absolute power minus reference absolute power divided by reference absolute power), representing the percentage increase in power from the reference interval to the excitation interval. Subjects were selected with scores (-1Z - + 1Z) on the Freiburg scale. An independent t-test assessed no significant difference between the two groups. Data beyond 1.5 times the interquartile range were defined as an outlier and removed. Normalized power of different frequency bands extracted from target channels was compared between two groups before and after presenting the independent variable using both ANCOVA and MANCOVA tests. Results Based on the findings of the ANCOVA test, mindfulness-based intervention decreased BP scores and increased the percentage of long responses in the experimental group compared to the control group. Mindfulness intervention has increased beta power at C3, F4, and Fz, delta at F3, Fz and Pz, theta at C4, F4 and Fz, and theta-to-beta size at C4, Cz, and Pz. Alpha power decreases in C3, F3, F4, and Fz, and increases in Cz and C3; alpha 1 decreases in C4 condition 1; Fz decrease in C4 condition 2 and 3; Cz and Pz decrease, and alpha 2 decreases in C3 condition 2 and C3 condition 7; C4 and F4 it has increased. Therefore, the alpha changes in C3 and F4 were contradictory, and it is impossible to make an integrated inference from the power changes of this wave in C3 and F4. Nevertheless, alpha power increased at C4, Cz, and Pz and decreased at F3 and Fz. Decreased gamma power was observed in F3, F4, and Fz, gamma 1 in F3, gamma 2 in C3, Cz, F3, F4, and Fz. As a result, it can be hypothesized that mindfulness may also improve temporal function by increasing motor inhibition. Conclusion Thus, mindfulness has led to an increase in the percentage of long responses (Plong) and a decrease in the bio section points (Bp), resulting in an overestimation of time perception.  Mindfulness increases beta, delta, and theta power, resulting in decreased arousal. The decrease in gamma, which indicates an increase in motor inhibition, physical awareness. and emotional regulation, was also proven in this study. The reduction in the theta-to-beta size, indicating an increase in internal focus, also shows in this study that mindfulness overestimates time by changing the outward-inward focus of attention. Therefore, these changes seem to be the electrophysiological mediators of the effect of mindfulness meditation on the process of cognitive processing of time perception in an overestimated way in time perception. Changes in alpha power were obtained inconsistently, requiring further research by examining the distinctive effect of alpha on the hemispheres. According to the results of this study, people estimate longer time intervals after performing mindfulness exercises by decreasing arousal, increasing attention to internal stimuli, and increasing motor inhibition. This effect occurs with the increasing power of beta, delta, and theta, and decreasing gamma, which are possible electrophysiological mediators in this process. Based on the contradictory alpha results, a more detailed study of alpha changes in the hemisphere is suggested.   Ethical considerations Compliance with ethical guidelines An ethical consent form approved by Tabriz University was obtained from all subjects. The present study consisted of data analysis, and it was approved by the Faculty of Educational Sciences and Psychology, University of Tabriz.   Authors' contributions Mohammad Ali Nazari, Mohammad Reza Feizi Derakhshi, and Touraj Hashemi guided the idea generation and design phase. Shahnaz Sabouri has done all the performing steps, sampling, and writing. Maryam Houri Pasand was involved in constructing the bio section task and its execution. Zeynab Khodakarami assisted in signal processing and data extraction, Behzad Golizadeh in statistical processing, and Homa Hashemi in typing and editing. Funding Personal funds funded this study. Acknowledgments The present article is the doctoral dissertation of the first author of this article (dated 2018/09/19 with the number 17/33419); therefore, the cooperation of all those who contributed to the advancement of this study is appreciated. I would also like to thank the Faculty of Educational Sciences and Psychology of Tabriz University for leading this research. Conflict of interest The authors declare no conflict of interest ادراک زمان, ذهن‌آگاهی, امواج مغزی, همزمان‌سازی وابسته به رویداد, ناهمزمان‌سازی وابسته به رویداد Time perception, Mindfulness, Brain waves, Event-related desynchronization, Event-related synchronization 33 47 http://icssjournal.ir/browse.php?a_code=A-10-829-2&slc_lang=fa&sid=1 Shahnaz Sabouri شهناز صبوری shahnazsabouri@yahoo.com 100319475328460012592 100319475328460012592 Yes PhD Student of Cognitive Neuroscience, Department of Psychology, University of Tabriz, Tabriz, Iran دانشجوی دکتری اعصاب شناختی، گروه روان‌شناسی، دانشگاه تبریز، تبریز، ایران Mohammad Ali Nazari محمد علی نظری 100319475328460012593 100319475328460012593 No Professor of Neuroscience, Laboratory of Cognitive Neuroscience, Faculty of Educational Sciences and Psychology, University of Tabriz, Tabriz, Iran استاد علوم اعصاب، آزمایشگاه علوم اعصاب شناختی، دانشکده علوم تربیتی و روان‌شناسی، دانشگاه تبریز، ایران Mohammad Reza Feizi Derakhshi محمدرضا فیضی درخشی 100319475328460012594 100319475328460012594 No Associate Professor of Computer Engineering, Artificial intelligence, Faculty of Electrical and Computer Engineering, University of Tabriz, Tabriz, Iran دانشیار مهندسی کامپیوتر، هوش مصنوعی، دانشکده مهندسی برق و کامپیوتر، دانشگاه تبریز، تبریز، ایران Tooraj Hashemi تورج هاشمی 100319475328460012595 100319475328460012595 No Professor of Educational Psychology, Faculty of Educational Sciences and Psychology, University of Tabriz, Tabriz, Iran استاد روان‌شناسی تربیتی، دانشکده علوم تربیتی و روان‌شناسی، دانشگاه تبریز، تبریز، ایران