Neuroimaging of Anesthetic Modulation of Human Consciousness

Inclusion Criteria:

1. Must have a body mass index (BMI) less than 30.
2. Must be right handed
3. Must be English speaking
4. Must be capable of giving written informed consent.
5. Must have history of playing tennis (or any type of racquet sport) at least 30 times over lifetime.

Exclusion Criteria:

1. History of obstructive sleep apnea;
2. History of a difficult airway with a previous anesthetic;
3. History of neurological disorders;
4. Hypertension or other cardiovascular abnormalities;
5. Pulmonary hypertension or other pulmonary abnormalities;
6. Gastroesophageal reflux disease (GERD) or heartburn;
7. History of significant head injury with loss of consciousness;
8. Learning disability or other developmental disorder;
9. Allergic reactions to eggs;
10. Pregnant or nursing mothers;
11. Contraindications to neuroimaging methods;
12. Inability or unwilling to fast, or withhold food and liquid intake, for 8 hours prior to your scheduled study visit.
13. Unwilling to abstain from alcohol use for 24 hours prior to your scheduled study visit.
14. History of drug use, or have a positive drug screen.
15. Tattoos on the head or neck region - all other tattoos are subject to determination by investigators.
16. Any impairment, activity or situation that in the judgment of the study coordinator or Principal Investigators would prevent satisfactory completion of the study protocol.