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An fMRI Study of the An fMRI Study of the Interaction of Stress and Interaction of Stress and Cocaine Cues on Cocaine Cocaine Cues on Cocaine
Craving in Cocaine-Craving in Cocaine-Dependent MenDependent Men
Cocaine addiction tough to treat because many patients show chronic relapse
Relapse is often preceded by1) Negative emotions2) Stressful life events
Limbic areas - Motivation and emotion Areas linked to dopamine system - reward
Anterior cingulate cortex Amygdala Nucleus accumbens Insula
Amygdala Bed nucleus of stria terminalis
Script-guided imagery of stressful situations Found that female cocaine users had
increased frontal and cingulate activation
How stress influences cocaine craving to better understand relapse process
About relationship between stress and craving in the brain
Stressful stimuli would enhance the activation of craving related neural pathways.
IVs: Stressor and Script-TypeDV: subjective measure of emotion OR fMRI activation
Participants Ten right-handed African American males Age range: 37-49 Administration method: smoking crack In early stage of drug abstinence (on avg
8) Met DSM-IV criteria for cocaine
dependence but no other disorders Unless substance-induced mood disorder
Procedure Baseline assessments of:
cocaine craving the week before testing ADHD Psychopathology Mental imagery ability
Script-guided mental imagery Listened to and mentally re-enacted scripts
One drug-related One drug-neutral
Stressor: threat of mild electric shock to wrist Told which part of testing would occur
fMRI scanning BOLD fMRI
Data analysis done with statistical parametric mapping software Based on probability of areas being activated
due solely to chance
Measure Mean (SD) RangeCCS—cocaine craving
4.85 (2.4) 1–10
QMI 59.4 (31) 35–116CAARS-SL 12.11 (8.4) 2–24BPRS 26.2 (6.6) 19–38
Baseline assessments
Within-Subjects ANOVA for: Shock condition – not significant Timepoint – Cocaine script resulted in
significantly higher craving than neutral script and baseline
Shock*Timepoint interaction – not significant
No significant changes at any timepoint during the session in subjective ratings of sadness, anxiety, or anger
Cocaine Scripts to Neutral Scripts1) Early: Early
Significant activation of: Anterior cingulate cortex Insula Posterior cingulate cortex
2) Late: LateSignificant activation of: Anterior cingulate cortex Insula
3) Entire cocaine script minus entire neutralActivation of: Anterior cingulate cortex Insula Posterior cingulate cortex
Cocaine (no stress): Cocaine (stress) Right thalamus Precuneus/posterior cingulate cortex→ Not significant
Cocaine (stress, late): Neutral (stress, late) Left insula→ Not significant
No activation differences when no stress: no stress
Effects seen in parietal lobes For “Early” these effects were significant in
the posterior cingulate cortex and right parietal
(For Cocaine*Stress)
1st Main Finding:Cocaine compared to neutral showed
activation of: Posterior cingulate cortex
Linked to anterior cingulate and amygdala; reward
Left insula Integration of internal body state associated with
emotions Right thalamus
Information relaying
2nd Main FindingStressor in cocaine condition resulted in
activation of: Left insula Anterior cingulate cortex
Evaluation of incentive cues and decision-making regarding reward
Results seen for stress situation not surprising as they are areas previously associated with conditioned cocaine craving.→ Responses not as strong as in prior studiesResults for reward make sense but areas missingNucleus accumbensPrefrontal cortexOrbitofrontal cortex
Limitations fMRI loud – harder to fully immerse self in
script Used PET in past
Imagery skills were not the same across all participants
Desired responding Not stressful enough
Cocaine scripts elicited responses in areas associated with rewards
Presence of cocaine script and stressor enhanced cocaine-induced reward activation Also attentional areas
Implications? Relaxation training for recovering addicts
Future studies: More participants
Duncan, E., Boshoven, W., Harenski, K., Fiallos, A., Tracy, H., Jovanovic, T., Hu, X., Drexler, K. & Kilts, C. (2007). An fMRI study of the interaction of stress and cocaine cues on cocaine craving in cocaine-dependent men. The American Journal on Addictions, 16, 174-182.