30 de setembro de 2020

Neurocircuitry of Addiction

26 de julho de 20112min

George F Koob*, and Nora D Volkow
Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, USA; National Institute on Drug Abuse, Bethesda, MD, USA

Drug addiction is a chronically relapsing disorder that has been characterized by  compulsion to seek and take the drug, ( loss of control in limiting intake, and  emergence of a negative emotional state (eg, dysphoria, anxiety, irritability) reflecting a  motivational withdrawal syndrome when access to the drug is prevented. Drug addiction has been conceptualized as a disorder that involves elements of both impulsivity and compulsivity that yield a composite addiction cycle composed of three  stages: ‘binge/intoxication’, ‘withdrawal/negative affect’, and ‘preoccupation/anticipation’ (craving).

Animal and human   imaging studies have revealed discrete circuits that mediate the three stages of the addiction cycle with key elements of the  ventral tegmental area and ventral striatum as a focal point for the binge/intoxication stage, a key role for the extended   amygdala in the withdrawal/negative affect stage, and a key role in the preoccupation/anticipation stage for a widely   distributed network involving the orbitofrontal cortex–dorsal striatum, prefrontal cortex, basolateral amygdala, hippocampus,  and insula involved in craving and the cingulate gyrus, dorsolateral prefrontal, and inferior frontal cortices in disrupted  inhibitory control.

The transition to addiction involves neuroplasticity in all of these structures that may begin with changes in  the mesolimbic dopamine system and a cascade of neuroadaptations from the ventral striatum to dorsal striatum and   orbitofrontal cortex and eventually dysregulation of the prefrontal cortex, cingulate gyrus, and extended amygdala.

Neurocircuitry of Addiction.pdf


Sobre a UNIAD

A Unidade de Pesquisa em álcool e Drogas (UNIAD) foi fundada em 1994 pelo Prof. Dr. Ronaldo Laranjeira e John Dunn, recém-chegados da Inglaterra. A criação contou, na época, com o apoio do Departamento de Psiquiatria da UNIFESP. Inicialmente (1994-1996) funcionou dentro do Complexo Hospital São Paulo, com o objetivo de atender funcionários dependentes.



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