Scientists watch Brain's garbage disposal during sleep

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

* INCLUSION CRITERIA: All Participants 1. Between 18 and 60 years of age as determined by self-report. 2. Ability to provide written informed consent as determined by physical examination and verbal communication. EXCLUSION CRITERIA: All Participants 1. Subjects with self-report of insomnia as determined by self-report and/or medical history; 2. Subjects with any of the following: narcolepsy, obstructive sleep apnea (OSA) and/or abnormal sleeping patterns (including but not limited to those who use a C-PAP machine, sleeping during the day, using medication to fall asleep, sleeps less than 6 hours per night, night shift workers), subjects reporting snoring as determined by self-report using STOP-BANG questionnaire for undiagnosed OSA (3 or more yes answers will exclude) and/or medical history; 3. Subjects with a history of restless leg syndrome as determined by self-report and/or medical history; 4. Use, in the past two weeks, of psychoactive medications (four weeks for fluoxetine) or medications that may affect brain function (including but not limited to opioid analgesics, tricyclic antidepressants, selective serotonin reuptake inhibitors \[SSRIs\], or serotonin norepinephrine reuptake inhibitors \[SNRIs\], benzodiazepines and barbiturates) as determined by self-report and/or medical history; 5. Current or past DSM-IV or DSM 5 diagnosis of a psychiatric disorder as determined by history and clinical exam including substance use disorder (except for nicotine/caffeine), alcoholism and alcohol dependence. Past history of a mental disorder as defined by DSM IV or DSM 5 will be excluded only if it required hospitalization (any length), or chronic medication management (more than 4 weeks), and that could impact brain function at the time of the study. 6. Major medical problems that can impact brain function at the time of the scan (e.g., problems of the CNS including seizures and psychosis; cardiovascular disease including hypertension and arrhythmias; metabolic, autoimmune, endocrine disorders) as determined by self-report, medical history and/or clinical exam. 7. Head trauma with loss of consciousness for more than 30 minutes as determined by self-report and/or medical history; 8. Positive test for controlled substances (cocaine, methamphetamine, amphetamines, opioids, cannabinoids, benzodiazepines and barbiturates) on any day of study including upon check-in to NIH CC as determined by urine toxicology; 9. Pregnant: Females must have negative urine pregnancy test 10. Presence of ferromagnetic objects in the body that are contraindicated for MRI of the head (including but not limited to pacemakers or other implanted electrical devices, brain stimulators, some types of dental implants, aneurysm clips, metallic prostheses, permanent eyeliner, implanted delivery pump, or shrapnel fragments) or fear of enclosed spaces as determined by the self-report checklist. 11. Fear of enclosed spaces (claustrophobia) as determined by self-report and medical history. 12. Cannot lie comfortably flat on the back for up to 3 hours in the MRI scanner as determined by self-report. 13. Body weight greater than 250 kg. This is the upper limit that the bed of the MR scanner can accommodate (clinical exam). 14. Alcohol consumption on the day of the MRI as determined by breath alcohol test 15. Study investigators and staff, as well as their superiors, subordinates and immediate family members (adult children, spouses, parents, siblings).