Pilot Study Comparing the Effectiveness of Two Different Methods of Acoustic Stimulation

Inclusion Criteria

• Able to provide written informed consent prior to admission
• Able to read, write and speak English
• Adult volunteers aged 21-50
• Working full time (M-F) schedule [Note: Full time is considered a 32 hour work week start time at 7am or later] or full time student
• Self-reported regular sleep schedule who are able to maintain their sleep schedule during the course of the study
• Self-reported sleep latency ≤ 30 minutes
• Self-reported wake after sleep onset ≤ 30 minutes
• Participants who regularly (3 of 5 work/school nights) use an alarm clock during the work/school week and who self-report:
• Regular sleep schedule of 5.5-7 hours +/- 15 minutes on work/school nights [confirmed by actigraphy at visit 2, at least 3 of 5 work/school nights between 5.5 to 7 hours total sleep time]
• Regular increase in sleep duration by ≥ 1 hour during non-work/school days as compared to work days, either by nocturnal bedtime extension or via a daytime nap [confirmed by actigraphy with at least 1 hour of increased sleep duration during one non-work/school night]
• Participants who demonstrate successful performance of the Paired Associates Learning Task during the training session

Exclusion Criteria

• Participation in another interventional study in the past 30 days.
• Major controlled* or uncontrolled medical condition such as congestive heart failure, neuromuscular disease, renal failure, cancer, Chronic Obstructive Pulmonary Disease (COPD), respiratory failure or insufficiency, or patients requiring oxygen therapy (as determined by self-report and reviewed by the study PI.)
• History of current or recent (e.g. within past 5 years) narcotic, or any other drug abuse.
• Daily caffeine intake > 650mg
• Current smoker (more than 6 cigarettes a week) or those using nicotine replacement therapy. Those that have been nicotine free for 30 days will be included.
• Currently working night shift, split shift or rotating shift (which includes night shifts).
• Current use, or use within the past month, of a prescription or over-the-counter sleep medication or stimulant; or use of psychoactive medication (based on self-report and review with a study clinician) Refer to table below for examples.
• Individuals who self-report a current severe or chronic medical condition that may affect sleep patterns (based on self-report and review with a study clinician).
• Pregnant or currently breast feeding
• Body Mass Index > 40 kg/m2
• Prior diagnosis (via self report) of any sleep disorder including:
• Obstructive Sleep Apnea (OSA) (AHI ≥15 events/hour) - from ambulatory or in lab polysomnography
• Restless legs syndrome, or periodic limb movement disorder
• Insomnia
• Parasomnia
• Circadian Rhythm Sleep-Wake Disorders
• High Risk of OSA based on STOP-BANG Questionnaire ("yes" on at least 4 of 8 questions)
• High risk of Restless Legs syndrome (RLS) base on Cambridge-Hopkins Screening Questionnaire
• High Risk of Insomnia based on Insomnia Severity Index (score of 22 or higher)
• Self-reported history of excessive alcohol intake - self-report > 21 drinks/week or binge alcohol consumption (>5 drinks per day)
• Individuals who self-report a history of recurrent seizures or epilepsy or family history of hereditary epilepsy or have a history of medical conditions that could increase the chance of seizures (e.g. stroke, aneurysm, brain surgery, structural brain lesion).
• Individuals who self-report severe contact dermatitis or allergy to silicone.
• Individuals who self-report moderate hearing loss.
• Inability to achieve appropriate headband fit (for prototype 1).
• Planned air travel or travel across more than one time zone during the anticipated period of the study with PowerSleep or PLL (Northwestern University) device use.
• Alpha-delta sleep on the first night in the sleep lab.
• Intentional naps during the work week.