The Spring Grove Experiment is a series of lysergic acid diethylamide (LSD) studies performed from 1963 to 1976 on patients with psychotic illnesses at the Spring Grove Clinic in Catonsville, Maryland. These patients were sponsored by a federal agency called the National Institute of Mental Health to be part of the first study conducted on the effects of psychedelic drugs on people with schizophrenia. Then, the Spring Grove Experiments were adapted to study the effect of LSD and psychotherapy on patients including alcoholics, heroin addicts, neurotics, and terminally-ill cancer patients. The research done was largely conducted by the members of the Research Unit of Spring Grove State Hospital. Significant contributors to the experiments included Walter Pahnke, Albert Kurland, Sanford Unger, Richard Yensen, Stanislav Grof, William Richards, Francesco Di Leo and Oliver Lee McCabe. Later, Spring Grove was rebuilt into the Maryland Psychiatric Research Center, where studies continued to be performed for the advancement of psychiatric research. This study on LSD is the largest study on psychedelic drugs to date. Historical context In 1943, Albert Hofmann discovered the hallucinogenic effects of LSD that led to an altered state of consciousness. In 1947, Gion Condrau and Arthur Stoll observed that people diagnosed as "psychotics" had a stronger tolerance for LSD and that the effects of the drug were similar to the symptoms expressed by psychotics themselves. In the late 1940s, English researcher Mayer-Gross found connections between schizophrenia and behaviors produced by LSD administration. In 1950, AK Busch and WC Johnson determined LSD's stimulative effects and first made the connection of LSD and its potential use in psychotherapy. In 1951, De Giacomo confirmed that when subjects with schizophrenia were given large dosages of LSD by mouth, they experienced a state of catatonia. He also stated that psychotic patients were more tolerant than healthy patients to LSD, and required higher dosages to produce responses. In 1953, D.W. Liddell and H. Weil-Malherbe studied the effects of LSD on mental processes and adrenaline in the blood and began characterizing the behaviors resulting from LSD administration to patients. They found that "depressive patients," experienced enhanced symptoms, becoming more depressed; while patients with schizophrenia experienced catatonic, or altered, states. They also found that after administering LSD through the patients' veins, adrenaline levels would fluctuate by rising, dropping, and rising, while blood glucose remained unaffected by the drug. Their method of administering LSD through the veins of patients with