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*Reward

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Gowin, J. L., Ball, T. M., Wittmann, M., Tapert, S. F., & Paulus, M. P. (2015). Individualized relapse prediction: Personality measures and striatal and insular activity during reward-processing robustly predict relapse. Drug and Alcohol Dependence, 152, 93–101. https://doi.org/10.1016/j.drugalcdep.2015.04.018

BACKGROUND: Nearly half of individuals with substance use disorders relapse in the year after treatment. A diagnostic tool to help clinicians make decisions regarding treatment does not exist for psychiatric conditions. Identifying individuals with high risk for relapse to substance use following abstinence has profound clinical consequences. This study aimed to develop neuroimaging as a robust tool to predict relapse. METHODS: 68 methamphetamine-dependent adults (15 female) were recruited from 28-day inpatient treatment. During treatment, participants completed a functional MRI scan that examined brain activation during reward processing. Patients were followed 1 year later to assess abstinence. We examined brain activation during reward processing between relapsing and abstaining individuals and employed three random forest prediction models (clinical and personality measures, neuroimaging measures, a combined model) to generate predictions for each participant regarding their relapse likelihood. RESULTS: 18 individuals relapsed. There were significant group by reward-size interactions for neural activation in the left insula and right striatum for rewards. Abstaining individuals showed increased activation for large, risky relative to small, safe rewards, whereas relapsing individuals failed to show differential activation between reward types. All three random forest models yielded good test characteristics such that a positive test for relapse yielded a likelihood ratio 2.63, whereas a negative test had a likelihood ratio of 0.48. CONCLUSIONS: These findings suggest that neuroimaging can be developed in combination with other measures as an instrument to predict relapse, advancing tools providers can use to make decisions about individualized treatment of substance use disorders.
Schienle, A., Schäfer, A., Hermann, A., & Vaitl, D. (2009). Binge-eating disorder: reward sensitivity and brain activation to images of food. Biological Psychiatry, 65(8), 654–661. https://doi.org/10.1016/j.biopsych.2008.09.028

BACKGROUND: The underlying neurobiological mechanisms that account for the onset and maintenance of binge-eating disorder (BED) are not sufficiently understood. This functional magnetic resonance imaging (fMRI) study explored the neural correlates of visually induced food reward and loathing. METHOD: Sixty-seven female participants assigned to one of four groups (overweight BED patients, overweight healthy control subjects, normal-weight healthy control subjects, and normal-weight patients with bulimia nervosa) participated in the experiment. After an overnight fast, the participants' brain activation was recorded during each of the following three conditions: visual exposure to high-caloric food, to disgust-inducing pictures, and to affectively neutral pictures. After the fMRI experiment, the participants rated the affective value of the pictures. RESULTS: Each of the groups experienced the food pictures as very pleasant. Relative to the neutral pictures, the visual food stimuli provoked increased activation in the orbitofrontal cortex (OFC), anterior cingulate cortex (ACC), and insula across all participants. The BED patients reported enhanced reward sensitivity and showed stronger medial OFC responses while viewing food pictures than all other groups. The bulimic patients displayed greater arousal, ACC activation, and insula activation than the other groups. Neural responses to the disgust-inducing pictures as well as trait disgust did not differ between the groups. CONCLUSIONS: This study provides first evidence of differential brain activation to visual food stimuli in patients suffering from BED and bulimia nervosa.
Kirsch, P., Reuter, M., Mier, D., Lonsdorf, T., Stark, R., Gallhofer, B., Vaitl, D., & Hennig, J. (2006). Imaging gene-substance interactions: the effect of the DRD2 TaqIA polymorphism and the dopamine agonist bromocriptine on the brain activation during the anticipation of reward. Neuroscience Letters, 405(3), 196–201. https://doi.org/10.1016/j.neulet.2006.07.030

Dopamine is known as the main neurotransmitter modulating the activation of the reward system of the brain. The DRD2 TaqIA polymorphism is associated with dopamine D2 receptor density which plays an important role in the context of reward. Persons carrying an A1 allele have a lower D2 receptor density and a higher risk to show substance abuse. The present study was designed to investigate the influence of the DRD2 TaqIA polymorphism and the selective D2 receptor agonist bromociptine on the activation of the reward system by means of functional magnetic resonance imaging (fMRI). In a double-blind crossover study with 24 participants we found an increase of reward system activation from placebo to bromocriptine only in subjects carrying the A1 allele. Furthermore, only A1 carrier showed an increase of performance under bromocriptine. The results are interpreted as reflecting a specific sensitivity for dopamine agonists in persons carrying an A1 allele and may complement actual data and theories of the development of addiction disorders postulating a higher genetic risk for substance abuse in carrier of the A1 allele.
Kirsch, P., Schienle, A., Stark, R., Sammer, G., Blecker, C., Walter, B., Ott, U., Burkart, J., & Vaitl, D. (2003). Anticipation of reward in a nonaversive differential conditioning paradigm and the brain reward system: an event-related fMRI study. NeuroImage, 20(2), 1086–1095. https://doi.org/10.1016/S1053-8119(03)00381-1

Findings from animal as well as human neuroimaging studies suggest that reward delivery is associated with the activation of subcortical limbic and prefrontal brain regions, including the thalamus, the striatum, the anterior cingulate and the prefrontal cortex. The aim of the present study was to explore if these reward-sensitive regions are also activated during the anticipation of reinforcers that vary with regard to their motivational value. A differential conditioning paradigm was performed, with the presentation of a rewarded reaction time task serving as the unconditioned stimulus (US). Depending on their reaction time, subjects were given (or not given) a monetary reward, or were presented with a verbal feedback consisting of being fast or slow. In a third control condition no task needed to be executed. Each of the three conditions was introduced by a different visual cue (CS). Brain activation of 27 subjects was recorded using event-related functional magnetic resonance imaging. The results showed significant activation of the substantia nigra, thalamic, striatal, and orbitofrontal brain regions as well as of the insula and the anterior cingulate during the presentation of a CS signalling a rewarded task. The anticipation of a monetary reward produced stronger activation in these regions than the anticipation of positive verbal feedback. The results are interpreted as reflecting the motivation-dependent reactivity of the brain reward system with highly motivating stimuli (monetary reward) leading to a stronger activation than those less motivating ones (verbal reward).

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Last update from database: 04.06.25, 15:35 (UTC)

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