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Cocaine-dependent individuals show altered brain activation during decision making. It is unclear, however, whether these activation differences are related to relapse vulnerability. This study tested the hypothesis that brain-activation patterns during reinforcement learning are linked to relapse 1 year later in individuals entering treatment for cocaine dependence. Subjects performed a Paper-Scissors-Rock task during functional magnetic resonance imaging (fMRI). A year later, we examined whether subjects had remained abstinent (n=15) or relapsed (n=15). Although the groups did not differ on demographic characteristics, behavioral performance, or lifetime substance use, abstinent patients reported greater motivation to win than relapsed patients. The fMRI results indicated that compared with abstinent individuals, relapsed users exhibited lower activation in (1) bilateral inferior frontal gyrus and striatum during decision making more generally; and (2) bilateral middle frontal gyrus and anterior insula during reward contingency learning in particular. Moreover, whereas abstinent patients exhibited greater left middle frontal and striatal activation to wins than losses, relapsed users did not demonstrate modulation in these regions as a function of outcome valence. Thus, individuals at high risk for relapse relative to those who are able to abstain allocate fewer neural resources to action-outcome contingency formation and decision making, as well as having less motivation to win on a laboratory-based task.
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This functional magnetic resonance imaging study investigated long-term effects of cognitive behavior therapy (CBT) in individuals suffering from spider phobia. Ten female patients who had shown positive immediate CBT effects were invited to take part in a 6-month follow-up investigation. Here, the patients, along with eight non-phobic females, were presented with the same pictures depicting spiders, generally disgust-inducing, generally fear-inducing and neutral content, which they had viewed 6 months earlier. Patients' self-report and overt behavior indicated a positive long-term clinical improvement. Related hemodynamic changes included an increase in medial orbitofrontal cortex (OFC) activity. As the medial OFC is involved in emotion-related learning, especially in the representation of positive stimulus-outcome associations, we conclude that the medial OFC effect constitutes the neuronal basis of the lasting positive CBT outcome. Activity to disorder-irrelevant pictures decreased across the sessions in the lateral OFC and in the insula, which most likely reflects general habituation.
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Thema
- Frontal Lobe/physiopathology
- Abstinence (1)
- Adult (2)
- Amygdala/physiopathology (1)
- Animals (1)
- Aversive Therapy (1)
- Brain/*physiopathology (1)
- Brain/physiopathology (1)
- Cerebral Cortex/physiopathology (2)
- Cocaine dependence (1)
- Cocaine-Related Disorders/*physiopathology (1)
- *Cognitive Behavioral Therapy (1)
- Corpus Striatum/*physiopathology (1)
- Decision Making (1)
- Emotions/physiology (1)
- Female (2)
- Follow-Up Studies (1)
- Functional magnetic resonance imaging (1)
- Humans (2)
- *Learning (1)
- Magnetic Resonance Imaging (2)
- Male (1)
- Middle Aged (1)
- Motivation (1)
- Phobic Disorders/physiopathology/psychology/*therapy (1)
- Recurrence (1)
- *Reinforcement, Psychology (1)
- Relapse (1)
- Reward (1)
- Spiders (1)
- Substance-Related Disorders/physiopathology (1)
- Treatment Outcome (1)
- Visual Perception (1)