28 de setembro de 2020

Marijuana craving in the brain

1 de setembro de 20093min

Proc Natl Acad Sci U S A. pnas.0903863106.

Published online 2009 July 24. doi: 10.1073/pnas.0903863106. PMCID: 2716383

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Marijuana craving in the brain

Francesca M. Filbey,ab1 Joseph P. Schacht,ac Ursula S. Myers,a Robert S. Chavez,a and Kent E. Hutchisonab

aThe Mind Research Network, 1101 Yale Boulevard, Albuquerque, NM 87106;

bDepartment of Psychology, University of New Mexico, 1 University of New Mexico, MSC03 2220, Albuquerque, NM 87131; and

cDepartment of Psychology and Neuroscience, Muenzinger D244, 345 UCB, University of Colorado, Boulder, CO 80309

Author contributions: F.M.F. and K.E.H. designed research; F.M.F., J.P.S., and U.S.M. performed research; F.M.F., J.P.S., U.S.M., and R.S.C. analyzed data; and F.M.F., J.P.S. and U.S.M. wrote the paper.

Edited by L. L. Iversen, University of Oxford, Oxford, United Kingdom, and approved June 23, 2009 (received for review April 10, 2009)

Received April 10, 2009; Accepted June 23, 2009.

Freely available online through the PNAS open access option.

AbstractCraving is one of the primary behavioral components of drug addiction, and cue-elicited craving is an especially powerful form of this construct. While cue-elicited craving and its underlying neurobiological mechanisms have been extensively studied with respect to alcohol and other drugs of abuse, the same cannot be said for marijuana. Cue-elicited craving for other drugs of abuse is associated with increased activity in a number of brain areas, particularly the reward pathway. This study used functional magnetic resonance imaging (fMRI) to examine cue-elicited craving for marijuana. Thirty-eight regular marijuana users abstained from use for 72 h and were presented with tactile marijuana-related and neutral cues while undergoing a fMRI scan. Several structures in the reward pathway, including the ventral tegmental area, thalamus, anterior cingulate, insula, and amygdala, demonstrated greater blood oxygen level dependent (BOLD) activation in response to the marijuana cue as compared with the neutral cue. These regions underlie motivated behavior and the attribution of incentive salience. Activation of the orbitofrontal cortex and nucleus accumbens was also positively correlated with problems related to marijuana use, such that greater BOLD activation was associated with greater number of items on a marijuana problem scale. Thus, cue-elicited craving for marijuana activates the reward neurocircuitry associated with the neuropathology of addiction, and the magnitude of activation of these structures is associated with severity of cannabis-related problems. These findings may inform the development of treatment strategies for cannabis dependence.

Keywords: cannabis, cue, fMRI, reward



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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.