This is a prospective dual parallel arm human subject study aimed at determining the relationship between level of sedation (consciousness) and features of multi and uni-sensory evoked potentials with the ultimate goal of developing novel means of detecting consciousness under anesthesia with potential for application to other clinical settings such as brain injury. For this purpose we chose two anesthetics with fundamentally distinct mechanisms of action: propofol and ketamine. Anesthesia with ketamine currently evades adequate detection using the available monitors of depth of anesthesia. Please see the rationale for dosing of the two anesthetics above. The study will involve healthy compensated volunteers. During the screening interview we will rule out the presence of any of the exclusion criteria (see below) and explain the details of the study to the subject. After questions concerning study design are answered we will obtain consent for the participation in the study. On the day of the study, EEG cap will be applied for monitoring brain activity and IV will be placed for drug administration. Blood pressure, ECG, pulse oxymetry, and end-tidal CO2 (from nasal cannula) will be monitored. Supplemental oxygen will be administered using a nasal cannula. Subjects will then perform the behavioral tasks in the awake state for approximately 1 hour.

You may be eligible for this study if you meet the following criteria:

• Conditions: Anesthesia Awareness
• Age: 99 years or below
• Gender: All