Study of SAGE-904 Using a Ketamine Challenge to Evaluate Electrophysiology, Safety, Tolerability, and Pharmacokinetics in Healthy Participants

Inclusion Criteria:

1. Participant is willing and able to provide 2 forms of identification; at least 1 must have a photo
2. Participant has a body weight ≥50 kilograms (kg) and body mass index ≥18.0 and ≤30.0 kilograms per square meter (kg/m\^2) at screening
3. Participant is healthy with no history or evidence of clinically relevant medical disorders as determined by the investigator
4. Participant has the ability to tolerate the electrode headset for the duration of the testing session

Exclusion Criteria:

1. Participant has a history or presence of any psychiatric disease or condition including suicidal ideation or behavior, has answered YES to any question on the Columbia-Suicide Severity Rating Scale (C-SSRS) at screening or admission, or is currently at risk of suicide in the opinion of the Investigator
2. Participant has a history or presence of a neurologic disease or condition, including, but not limited to, epilepsy, closed head trauma with clinically significant (CS) sequelae, or a prior seizure
3. Participant has a family history of epilepsy
4. Participant has a history, presence, and/or current evidence of serologic positive results for Hepatitis B and C, human immunodeficiency virus (HIV) 1 or 2
5. Participant has obstructed venous access and/or has skin disease, rash, acne, or abrasion at venous access site that may affect the ability to obtain a pharmacokinetic (PK) sample or affect the ability to receive the ketamine infusions
6. Participant has had previous exposure to or is known to be allergic to ketamine or any of its excipients