Nora Volkow
Encyclopedia
Nora Volkow is director of the National Institute on Drug Abuse (NIDA)
National Institute on Drug Abuse
The National Institute on Drug Abuse is a United States federal-government research institute whose mission is to "lead the Nation in bringing the power of science to bear on drug abuse and addiction."-History:...

. She is the great-granddaughter of Russian revolutionary leader and Head of the Fourth International
Fourth International
The Fourth International is the communist international organisation consisting of followers of Leon Trotsky , with the declared dedicated goal of helping the working class bring about socialism...

, Leon Trotsky
Leon Trotsky
Leon Trotsky , born Lev Davidovich Bronshtein, was a Russian Marxist revolutionary and theorist, Soviet politician, and the founder and first leader of the Red Army....

. Her father was the son of Leon Trotsky’s elder daughter.

Born in Mexico City, Volkow and her three sisters grew up in the house where Trotsky was killed. She attended the Modern American School, then earned a medical degree from National University of Mexico before going to New York University
New York University
New York University is a private, nonsectarian research university based in New York City. NYU's main campus is situated in the Greenwich Village section of Manhattan...

 for psychiatric
Psychiatry
Psychiatry is the medical specialty devoted to the study and treatment of mental disorders. These mental disorders include various affective, behavioural, cognitive and perceptual abnormalities...

 residency. She chose a career in brain
Brain
The brain is the center of the nervous system in all vertebrate and most invertebrate animals—only a few primitive invertebrates such as sponges, jellyfish, sea squirts and starfishes do not have one. It is located in the head, usually close to primary sensory apparatus such as vision, hearing,...

 research after reading an article on the use of positron emission tomography
Positron emission tomography
Positron emission tomography is nuclear medicine imaging technique that produces a three-dimensional image or picture of functional processes in the body. The system detects pairs of gamma rays emitted indirectly by a positron-emitting radionuclide , which is introduced into the body on a...

 in studying brain function. She did research at Brookhaven National Laboratory
Brookhaven National Laboratory
Brookhaven National Laboratory , is a United States national laboratory located in Upton, New York on Long Island, and was formally established in 1947 at the site of Camp Upton, a former U.S. Army base...

 before becoming director of NIDA in 2003.

Research

Her imaging studies of the brains of people addicted to drugs have helped to clarify the mechanisms of drug addiction. They have also helped to change the public's view of drug addiction, from that of a moral
Moral
A moral is a message conveyed or a lesson to be learned from a story or event. The moral may be left to the hearer, reader or viewer to determine for themselves, or may be explicitly encapsulated in a maxim...

 violation or character flaw
Character flaw
In the creation and criticism of fictional works, a character flaw is a limitation, imperfection, problem, phobia, or deficiency present in a character who may be otherwise very functional. The flaw can be a problem that directly affects the character's actions and abilities, such as a violent temper...

 to an understanding that pathological changes to brain structure make it very difficult for addicts to give up their addictions. Volkow has shown that abnormalities in the prefrontal cortex
Prefrontal cortex
The prefrontal cortex is the anterior part of the frontal lobes of the brain, lying in front of the motor and premotor areas.This brain region has been implicated in planning complex cognitive behaviors, personality expression, decision making and moderating correct social behavior...

 of addicts create a feeling of need or craving that addicts know is irrational but cannot prevent. Prefrontal abnormalities also make it difficult to override compulsions to take drugs by exercising cognitive control. The main areas affected are the orbitofrontal cortex
Orbitofrontal cortex
The orbitofrontal cortex is a prefrontal cortex region in the frontal lobes in the brain which is involved in the cognitive processing of decision-making...

, which maintains attention to goals, and the anterior cingulate cortex
Cingulate cortex
The cingulate cortex is a part of the brain situated in the medial aspect of the cortex. It includes the cortex of the cingulate gyrus, which lies immediately above the corpus callosum, and the continuation of this in the cingulate sulcus...

, that mediates the capacity to monitor and select action plans. Both areas receive stimulation from dopamine
Dopamine
Dopamine is a catecholamine neurotransmitter present in a wide variety of animals, including both vertebrates and invertebrates. In the brain, this substituted phenethylamine functions as a neurotransmitter, activating the five known types of dopamine receptors—D1, D2, D3, D4, and D5—and their...

 centers lower in the brain. A steady influx of dopamine makes it difficult for addicts to shift their attention away from the goal of attaining drugs. It also fastens their attention to the motivation
Motivation
Motivation is the driving force by which humans achieve their goals. Motivation is said to be intrinsic or extrinsic. The term is generally used for humans but it can also be used to describe the causes for animal behavior as well. This article refers to human motivation...

al value of drugs, even though these drugs have long stopped providing pleasure. It is now understood that dopamine activation does not signal pleasure
Pleasure
Pleasure describes the broad class of mental states that humans and other animals experience as positive, enjoyable, or worth seeking. It includes more specific mental states such as happiness, entertainment, enjoyment, ecstasy, and euphoria...

. Rather, it signals the importance or relevance of sought-after goals. Addicts have a hard time turning their attention —and their actions— away from the goal of acquiring and consuming drugs. They are caught in a vicious circle
Virtuous circle and vicious circle
A virtuous circle and a vicious circle are economic terms. They refer to a complex of events that reinforces itself through a feedback loop. A virtuous circle has favorable results, while a vicious circle has detrimental results...

 of physical brain changes and the psychological consequences of those changes, leading to further changes.

External links

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