Automatic Versus Evaluative Components of Cue Reactivity
Paraules clau
Resum
Descripció
Relapse to drug abuse often happens in the presence of stimuli that are associated with previous drug-use, and drug-taking behavior appears to be partly controlled by such cues. While some theories postulate that such facilitation is mediated by cue-induced craving states, others hypothesize that the underlying processes are highly automatized and can happen without conscious control or even awareness. One way to approach psychological mechanisms of cue reactivity is to measure disruption of ongoing mental activity by drug-related material in dependent individuals while manipulating the degree to which cognitive evaluative processes can unfold. Craving measurement under these conditions can elucidate its relationship with automatic processing versus conscious evaluation of drug cues. Autonomic and neural correlates can be identified by concomitant psychophysiological and fMRI recording. Results from these studies will shed light on the role of spontaneous automatic reactions versus cognitive evaluation for different measures of cue reactivity. By helping to elucidate the psychological mechanisms and neurobiological basis of drug-cue reactivity in dependent individuals, this may have substantial implications for the understanding of mechanisms and treatment of drug dependence. Thus, while there are no direct benefits to subjects participating in these experiments, the results may benefit the health of society. MRI-related risks to subjects (injury from metal implants, claustrophobia, temporary deafness due to the loud banging noises) will be minimized by prescreening and providing earplugs. Drug-related cues may induce acute craving; subjects will be dismissed only after craving levels have returned to baseline.
Dates
| Darrera verificació: | 08/18/2010 |
| Primer enviat: | 12/17/2009 |
| Inscripció estimada enviada: | 12/17/2009 |
| Publicat per primera vegada: | 12/20/2009 |
| Última actualització enviada: | 06/29/2017 |
| Publicació de l'última actualització: | 07/01/2017 |
| Data d'inici de l'estudi real: | 08/11/2003 |
| Data estimada de finalització de l’estudi: | 08/18/2010 |
Condició o malaltia
Fase
Criteris d'elegibilitat
| Edats elegibles per estudiar | 18 Years Per a 18 Years |
| Sexes elegibles per estudiar | All |
| Accepta voluntaris saludables | Sí |
| Criteris | - INCLUSION CRITERIA: Smokers: Regular smoking of greater than or equal to 20 cigarettes other than ultra-low nicotine cigarettes per day for at least two years. Experienced withdrawal signs after not smoking for several hours. Score on the Fagerstrom Test for Nicotine Dependence greater than or equal to 3. No intention to quit or reduce tobacco use, and no treatment for tobacco dependence currently or during the previous 3 months. No history of abuse of or dependence to any other drug. Age at least 18 and not older than 50 years. Controls: Smoked less than 5 cigarettes during lifetime No history of abuse of or dependence to any drug, including alcohol. Age at least 18 and not older than 50 years. Cocaine abusers: Reported regular crack-cocaine use for at least six months. Meeting DSM-IV criteria for cocaine dependence. No intention to quit or reduce cocaine use, and no treatment for cocaine dependence currently or during the previous 3 months. No dependence on any other drug except nicotine. Recreational use of other drugs of abuse without meeting dependence criteria is not an exclusion criterion. Age at least 18 and not older than 50 years. Controls: No history of dependence on any drug except nicotine. Age at least 18 and not older than 50 years. EXCLUSION CRITERIA: All subject groups Female subjects: pregnancy (a urine pregnancy test will be performed before each MRI experimental session). Presence of metal objects in the body (e.g. some artificial joints, bone pins, surgical clips, skull plate, dental braces) or implanted electronic devices (e.g. cardiac pacemaker, neurostimulator) Claustrophobia. For experiments involving MRI, left-handed or ambidextrous as determined by the Edinburgh Handedness Inventory. Cardiovascular or cerebrovascular diseases. Major psychiatric disorders including mood, anxiety or psychotic disorders. History of or current neurological illnesses including seizure disorders, migraine, multiple sclerosis, movement disorders, head trauma, CVA or CNS tumor. Gross structural brain abnormalities as revealed by T1 weighted images. Use of medication that may affect the CNS at the time of scanning (e.g. b-blocker or analgesics). Learning disability, amnesia or other conditions that impede memory and attention. IQ less than 85. HIV-positivity. |
