This research is a prospective cohort study. The aim of the study is to determine different levels of sedative mechanism and the effect on brain functional connectivity of midazolam, dexmedetomidine and propofol.

This research will include 120 healthy volunteers and 120 brain tumor patients; the participants will be allocated into midazolam, dexmedetomidine and propofol group. Resting and task fMRI will be performed at awake (BIS>90), mild sedation (BIS 80-85), moderate sedation (BIS 65-75), deep sedation (BIS 45-55) and recovery states (BIS >90). The primary outcome of our study is the effect of different levels of sedation for brain network connection. The secondary outcomes are the effect of different levels of sedation for default, executive control, sensory and motor networks and their subnetwork connectivity; the sedation state, circulatory and respiratory parameters of the participants, and the adverse events.

Inclusion Criteria:

• 1. Male, 18 ~ 65 years old
• 2. Healthy Volunteer / Brain Tumor Patients
• 3. Senior high school and above
• 4. Sign informed consent

Exclusion Criteria:

• 1. In vivo implant MRI check taboo
• 2. Cardiopulmonary liver and kidney and other systemic complications
• 3. History of major surgical anesthesia
• 4. Abuse of drugs, alcoholism history
• 5. Test drug allergy history
• 6. Claustrophobia
• 7. Left hand