This study is being conducted in order to understand more about how the body responds to a mind/body practice called yoga nidra. Results from this study will be used to inform the design of future studies that investigate the effects of yoga nidra on sleep quality and insomnia.

Yoga nidra is a simple guided meditation technique that involves lying still on a mattress while listening to a voice. Participants will follow simple instructions that involve becoming aware of their body and breath, as well as various memories, emotions, and images. This practice is not religious in nature. The investigators do not believe it will conflict with any religious beliefs. The goal of this practice is to help get rid of mental, physical and emotional tensions.

This clinical trial explores the physiological effects of yoga nidra and its connection to sleep. The investigators will measure patterns in brainwave activity, respiration and heart rate variability using EEG, and two wireless devices: the Spire® breath monitor and the Bodyguard® HRV monitor. This study will also address feasibility questions related to credibility and acceptability, using self-report surveys, drop-out rates, and participant feedback. Twenty-two participants will be recruited using digital and paper advertisements throughout Portland and the National University of Natural Medicine (NUNM). Interested individuals will contact the study coordinator, and then complete a screening call. During this telephone screening, the study coordinator will ask general questions and use standardized surveys to exclude participants based on inclusion/exclusion criteria. Prospective participants who pass the telephone screening will then be invited for two visits to the Helfgott Research Institute. Each visit will involve informed consent, followed by the completion of two eligibility surveys, and several intake questionnaires. The measurement periods will involve: 10 minutes of baseline data collection, 30 minutes of lying quietly or listening to a recording of yoga nidra, and then 1 hour of resting comfortably. Participants will be allowed to fall asleep during this time and will be left alone in the room with the lights out during the entire intervention (after the first 10 minutes of baseline data collection). When finished, participants will complete a few short questionnaires before their departure. The first visit will involve lying quietly as a baseline control. At the second visit, half of the population will be randomly selected to do yoga nidra and half will complete the baseline control measurements again.

Inclusion Criteria:

• Insomnia severity index (ISI) score 8-21 (subthreshold to moderately severe clinical insomnia)
• Can understand a recording in English

Exclusion Criteria:

• prescription sleeping medications
• regular mind/body practice within last 6 months
• diagnosed depression (or Patient Health Questionnaire (PHQ-2 into PHQ-9) score above 10)
• diagnosed sleep apnea (or STOP-BANG Sleep Apnea Questionnaire score of 3 or more)
• excessive alcohol use
• cannabis use
• smoking
• stimulant use
• shift work
• fibromyalgia