Ronald Keith Siegel is an American psychiatrist, research professor in the Department of Psychiatry and Biobehavioral Sciences at the University of California, Los Angeles

University of California, Los Angeles

The University of California, Los Angeles is a public research university located in the Westwood neighborhood of Los Angeles, California, USA. It was founded in 1919 as the "Southern Branch" of the University of California and is the second oldest of the ten campuses...

 (as recently as 2005), and the author of several noted studies and books on psychopharmacology

Psychopharmacology

Psychopharmacology is the scientific study of the actions of drugs and their effects on mood, sensation, thinking, and behavior...

, hallucination

Hallucination

A hallucination, in the broadest sense of the word, is a perception in the absence of a stimulus. In a stricter sense, hallucinations are defined as perceptions in a conscious and awake state in the absence of external stimuli which have qualities of real perception, in that they are vivid,...

, and paranoia

Paranoia

Paranoia [] is a thought process believed to be heavily influenced by anxiety or fear, often to the point of irrationality and delusion. Paranoid thinking typically includes persecutory beliefs, or beliefs of conspiracy concerning a perceived threat towards oneself...

. Siegel has studied, lectured, and conducted research at Brandeis University

Brandeis University

Brandeis University is an American private research university with a liberal arts focus. It is located in the southwestern corner of Waltham, Massachusetts, nine miles west of Boston. The University has an enrollment of approximately 3,200 undergraduate and 2,100 graduate students. In 2011, it...

, Harvard Medical School

Harvard Medical School

Harvard Medical School is the graduate medical school of Harvard University. It is located in the Longwood Medical Area of the Mission Hill neighborhood of Boston, Massachusetts....

, Dalhousie University

Dalhousie University

Dalhousie University is a public research university located in Halifax, Nova Scotia, Canada. The university comprises eleven faculties including Schulich School of Law and Dalhousie University Faculty of Medicine. It also includes the faculties of architecture, planning and engineering located at...

, and the Albert Einstein College of Medicine

Albert Einstein College of Medicine

Albert Einstein College of Medicine is a graduate school of Yeshiva University. It is a not-for-profit, private, nonsectarian medical school located on the Jack and Pearl Resnick Campus in the Morris Park neighborhood of the borough of the Bronx of New York City...

, and has been a consultant to several government commissions on drug use. His research has focused on the effects of drugs on human behavior, and has included numerous clinical studies in which human volunteers (sometimes referred to by Siegel as "psychonauts") have taken drugs such as ketamine

Ketamine

Ketamine is a drug used in human and veterinary medicine. Its hydrochloride salt is sold as Ketanest, Ketaset, and Ketalar. Pharmacologically, ketamine is classified as an NMDA receptor antagonist...

, LSD

LSD

Lysergic acid diethylamide, abbreviated LSD or LSD-25, also known as lysergide and colloquially as acid, is a semisynthetic psychedelic drug of the ergoline family, well known for its psychological effects which can include altered thinking processes, closed and open eye visuals, synaesthesia, an...

, marijuana, mescaline

Mescaline

Mescaline or 3,4,5-trimethoxyphenethylamine is a naturally occurring psychedelic alkaloid of the phenethylamine class used mainly as an entheogen....

, psilocybin

Psilocybin

Psilocybin is a naturally occurring psychedelic prodrug, with mind-altering effects similar to those of LSD and mescaline, after it is converted to psilocin. The effects can include altered thinking processes, perceptual distortions, an altered sense of time, and spiritual experiences, as well as...

, and THC

THC

THC commonly refers to tetrahydrocannabinol, the main active chemical compound in Cannabis.THC may also refer to:* Tan Holdings Corporation...

.

In 2005, Siegel was an expert witness for the defense in the Robert Blake

Robert Blake (actor)

Robert Blake is an American actor who starred in the film In Cold Blood and the U.S. television series Baretta. In 2005, he was tried and acquitted for the 2001 murder of his wife, but on November 18, 2005, Blake was found liable in a California civil court for her wrongful death.-Early...

 murder trial, testifying on the long-term effects of methamphetamine

Methamphetamine

Methamphetamine is a psychostimulant of the phenethylamine and amphetamine class of psychoactive drugs...

 and cocaine

Cocaine

Cocaine is a crystalline tropane alkaloid that is obtained from the leaves of the coca plant. The name comes from "coca" in addition to the alkaloid suffix -ine, forming cocaine. It is a stimulant of the central nervous system, an appetite suppressant, and a topical anesthetic...

 use. According to the jury foreman in the trial, Siegel was "one of the most compelling witnesses" in discrediting the testimony of Ronald Hambleton, who claimed that Blake had asked him to murder Bonnie Lee Bakley

Bonnie Lee Bakley

Bonnie Lee Bakley was the wife of actor Robert Blake.-Early life:Bonny Lee Bakley was born in Morristown, New Jersey to arborist Edward J. Bakley and his wife, Marjorie Lois Bakley. Bakley had three other siblings: Margerry Lisa Bakley, Joe Bakley, and her half-brother Peter Carlyon from her...

. In the course of his testimony in the Blake trial, Siegel disclosed that in one study, he had taught monkeys to smoke crack cocaine

Crack cocaine

Crack cocaine is the freebase form of cocaine that can be smoked. It may also be termed rock, hard, iron, cavvy, base, or just crack; it is the most addictive form of cocaine. Crack rocks offer a short but intense high to smokers...

.

In the early 1980s, Siegel administered large oral doses of LSD to two elephants.

Books

• Intoxication: The Universal Drive for Mind-Altering Substances (2005, 1989)
• Whispers: The Voices of Paranoia (1994)
• Fire in the Brain: Clinical Tales of Hallucination (1992)
• Hallucinations: Behavior, Experience, and Theory (with L.J. West) (1975)