The purpose of this study is to investigate the effects of flumazenil on cortical excitability in healthy human volunteers. Flumazenil acts as a potent benzodiazepine (BZP)-specific antagonist by competing at the central synaptic gamma-aminobutyric acid (GABA) receptor site. However, the relationship between GABA and flumazenil without BZPs is not well known. We plan to determine if intravenous (IV) administration in therapeutic dosage alters cortical excitability as measured by transcranial magnetic stimulation (TMS). The long-term plan is to identify a pharmacological method to reduce cortical inhibition that might be useful in stroke rehabilitation.
Only healthy volunteers, who are age 21 or older. No history of surgery with metallic implants or known metallic particles in the brain. Patients cannot be pregnant (as tested with a pregnancy test). Patients with a psychiatric illness are not eligible. No history of seizures. No cardiovascular disease or drug therapy for chronic depression. No hypersensitivity to benzodiazepines and related drugs. No history of drug abuse and/or chronic alcoholism.