Eligibility Details:
Inclusion Criteria:
1. Participants must be between 18-55 years of age, free of any current or past
neurological or psychiatric illness, and capable of performing all tasks during each
session of the experiment.
2. They must be able to provide written informed consent and must have sufficient
proficiency in the English language to understand and complete interviews,
questionnaires, and all other study procedures.
Exclusion Criteria:
1. Participant meets criteria for a DSM5 Axis-1 disorder.
2. Participant endorses current suicidal ideation with intent or plan.
3. Participant fails to adhere to our "Pre-float checklist".
4. Participant is morbidly obese (BMI > 40).
5. Certain drugs or medications consumed within the past week including any psychoactive
drugs (e.g., benzodiazepines, opiates, selective serotonin reuptake inhibitors,
dopamine agonists, barbiturates, MDMA, LSD, psilocybin, peyote, phencyclidine,
ketamine). For all other medications, we require the participant to be stably
medicated prior to participation (defined as having taken the medication for 6 weeks
or longer).
6. Participant has a history of unstable liver or renal insufficiency; glaucoma;
diabetes; significant and unstable cardiac, vascular, pulmonary, gastrointestinal,
endocrine, neurologic, hematologic, rheumatologic, or metabolic disturbance; or any
other condition that, in the opinion of the investigator, would make participation not
be in the best interest (e.g., compromise the well-being) of the subject or that could
prevent, limit, or confound the protocol-specified assessments.
7. Pregnancy as detected by a urine test.
8. Non-correctable vision or hearing problems.
9. MRI contraindications including: cardiac pacemaker, metal fragments in eyes/skin/body
(shrapnel), aortic/aneurysm clips, prosthesis, by-pass surgery/coronary artery clips,
hearing aid, heart valve replacement, shunt (ventricular or spinal), electrodes, metal
plates/pins/screws/ wires, or neuro/bio-stimulators (TENS unit), persons who have ever
been a professional metal worker/welder, history of eye surgery/eyes washed out
because of metal, vision problems uncorrectable with lenses, inability to lie still on
one's back for 60-120 minutes; prior neurosurgery; tattoos or cosmetic makeup with
metal dyes, unwillingness to remove body piercings, and pregnancy.