Ithaca College Digital Commons @ IC Ithaca College Theses 2014 Effects of theta-frequency binaural beats on post- exercise recovery and stress responsivity Patrick McConnell Ithaca College Follow this and additional works at: http://digitalcommons.ithaca.edu/ic_theses Part of the Sports Sciences Commons Recommended Citation McConnell, Patrick, "Effects of theta-frequency binaural beats on post-exercise recovery and stress responsivity" (2014). Ithaca College Theses. Paper 16. This Thesis is brought to you for free and open access by Digital Commons @ IC. It has been accepted for inclusion in Ithaca College Theses by an authorized administrator of Digital Commons @ IC. EFFECTS OF THETA-FREQUENCY BINAURAL BEATS ON POST-EXERCISE RECOVERY AND STRESS RESPONSIVITY A Master’s Thesis Presented to the Faculty of the Graduate Program in Exercise and Sport Sciences Ithaca College In partial fulfillment of the requirements for the degree Master of Science by Patrick McConnell May 2014 Ithaca College School of Health Sciences and Human Performance Ithaca, New York CERTIFICATE OF APPROVAL MASTER OF SCIENCE THESIS This is to certify that the Thesis of Patrick McConnell Submitted in partial fulfillment of the requirements for the degree of Master of Science in the School of Health Science and Human Performance at Ithaca College has been approved. Thesis Advisor: Committee Member: Candidate: Chair, Graduate Program Dean, School of Health Sciences and Human Performance Date: ABSTRACT Binaural beats are an auditory illusion perceived when two or more pure tones of similar frequencies are presented dichotically through stereo headphones. This phenomenon is thought to have the potential to facilitate changes in arousal. The present study investigated the effects of 7 Hz binaural beating on post-exercise recovery and stress responsivity in college-aged students (n = 21; 18-29 years old). Psychological measures consisted of the positive and negative affect schedule and self-reported stress and relaxation. Physiological measures consisted of heart rate, heart rate variability, blood pressure and salivary α-amylase. Participants visited the laboratory twice over a two-week period at the same time of day to complete both a control (pink noise and carrier tone placebo) and an experimental (multilayered theta-frequency binaural beats with pink noise) session in a crossover controlled design. Participants exercised for 20- min at 70% of their predicted VO2max with a 5-min warm-up and cool-down at 50% of their exercise workload. After exercising, participants listened to either binaural beats or placebo while relaxing alone in a quiet, low-light environment. Lastly, participants completed a short, timed 20-question mental arithmetic battery designed to elicit a stress response. Measurements were taken at four time points during each session: at baseline, post-exercise, post-relaxation and post-stress. Heart rate variability analyses comprised 2- min windows corresponding to salivary-amylase acquisition. Theta binaural beats failed to outperform placebo in altering post-exercise recovery or stress responsivity. However, after listening to binaural beats, participants reported feeling more relaxed (6.4% change) and less stressed (11.5% change). Findings from the present study suggest that listening to binaural beats may have subtle psychological effects. Further research in a sample more representative of the general population is recommended. iii ACKNOWLEDGEMENTS Thanks to the following people who helped make this project manifest: To Dr. Sforzo, for his honesty, for challenging me and for teaching me how to approach the pursuit of science. To Dr. Ives, for helping me improve my scientific writing skills and for always maintaining a sense of humor. To the Monroe Institute, for kindly providing the experimental stimuli. To Bill, for always having an open door and an open mind. To my Mom, for all the hours of transcribing data and everything else. Thank you all! iv DEDICATION This thesis is dedicated to my parents and family and also to Robert Monroe and the kind folks at the Monroe Institute. To my parents, who have supported me and spurred me onwards and upwards continuously throughout the years; none of this would have been possible without your love and kindness. Thank you! To Robert Monroe, whose work kindled in me an unquenchable curiosity for the unknown. Safe travels wherever you may be. v TABLE OF CONTENTS Page ABSTRACT ....................................................................................................................... iii ACKNOWLEDGEMENTS ............................................................................................... iv DEDICATION .................................................................................................................... v LIST OF FIGURES ............................................................................................................ x LIST OF TABLES ............................................................................................................. xi Chapter 1. INTRODUCTION .............................................................................................. 1 Statement of Purpose .................................................................................. 4 Hypotheses .................................................................................................. 4 Assumptions of the Study ........................................................................... 5 Definition of Terms .................................................................................... 6 Delimitations ............................................................................................... 7 Limitations .................................................................................................. 8 2. REVIEW OF LITERATURE ............................................................................. 9 Relevant Neuroanatomy and Neurophysiology .......................................... 9 Brainstem anatomy ......................................................................... 9 The human auditory system and music ......................................... 10 Overview of the electroencephalogram ........................................ 10 Overview of entrainment .............................................................. 11 Binaural beat entrainment ............................................................. 12 Overview of Clinical Binaural Beat Research .......................................... 15 Autonomic Arousal: Stress and Relaxation Responses ............................ 17 The stress response ....................................................................... 17 Heart rate variability ..................................................................... 18 Time-domain measures ..................................................... 18 Frequency-domain measures ............................................ 19 Artifact removal and pre-processing of the HRV signal .............. 20 Salivary α-amylase ........................................................................ 20 vi TABLE OF CONTENTS (continued) Chapter Page Consciousness, Attention and Trance ....................................................... 22 The relaxation response ................................................................ 24 Hypnosis ....................................................................................... 25 Exercise ..................................................................................................... 26 Summary ................................................................................................... 28 3. METHODS ....................................................................................................... 29 Participants ................................................................................................ 29 Equipment and Measures .......................................................................... 30 Cardiovascular measures and analyses ......................................... 30 Enzymatic analysis ....................................................................... 31 Acoustic equipment ...................................................................... 31 Pre- and post- screening questionnaires ........................................ 32 Pre-participation screening questionnaire (PPSQ) ............ 33 Physical activity rating (PA-R) ......................................... 33 Perceived functional ability questionnaire (PFA) ............. 33 Post-participation screening questionnaire (Post-PSQ) .... 33 Psychometric instruments ............................................................. 34 Mental arithmetic battery .................................................. 34 The positive and negative affect schedule (PANAS) ....... 34 Rate of perceived exertion scale (RPE) ............................ 34 Procedures ................................................................................................. 35 HRV Data Processing ............................................................................... 38 Statistical Analyses ................................................................................... 39 4. RESULTS ......................................................................................................... 41 Psychological Measures ............................................................................ 41 State positive affect (PA) .............................................................