Objective: In this study, we investigate the brain mechanisms of the conscious regulation of the desire for food using functional magnetic resonance imaging. Further, we examine associations between hemodynamic responses and participants' cognitive restraint of eating (CRE), as well as their susceptibility to uncontrolled eating. Subjects: Seventeen non-vegetarian, right-handed, female Caucasian participants (age: 20-30 years, mean 25.3 years±3.1 s.d.; BMI: 20.2-31.2 kg m À2 , mean 25.1 ± 3.5 s.d.). Measurements: During scanning, our participants viewed pictures of food items they had pre-rated according to tastiness and healthiness. Participants were either allowed to admit to the desire for the food (ADMIT) or they were instructed to downregulate their desire using a cognitive reappraisal strategy, that is, thinking of negative long-term health-related and social consequences (REGULATE).Results: Comparing the hemodynamic responses of the REGULATE with the ADMIT condition, we observed robust activation in the dorsolateral prefrontal cortex (DLPFC), the pre-supplementary motor area, the inferior frontal gyrus (IFG), the dorsal striatum (DS), the bilateral orbitofrontal cortex (OFC), the anterior insula and the temporo-parietal junction (TPJ). Activation in the DLPFC and the DS strongly correlated with the degree of dietary restraint under both conditions. Conclusion: Cortical activation in the DLPFC, the pre-supplementary motor area and the inferior frontal gyrus (IFG) are known to underpin top-down control, inhibition of learned associations and pre-potent responses. The observed hemodynamic responses in the lateral OFC, the DS, the anterior insula and the TPJ support the notion of reward valuation and integration, interoceptive awareness, and self-reflection as key processes during active regulation of desire for food. In conclusion, an active reappraisal of unhealthy food recruits the brain's valuation system in combination with prefrontal cognitive control areas associated with response inhibition. The correlations between brain responses and CRE suggest that individuals with increased cognitive restraint show an automatic predisposition to regulate the hedonic aspects of food stimuli. This cognitive control might be necessary to counterbalance a lack of homeostatic mechanisms.

This study is the first to reveal quadratic relationships of food-related brain processes and BMI. Reported nonlinear associations indicate inverse relationships between regulation-related motivational processing in the range of normal weight/overweight compared with the obese range. Connectivity analyses suggest that the need for top-down (dlPFC) adjustment of striatal value representations increases with BMI, whereas the interplay of self-monitoring (dmPFC) or eating-related strategic action planning (caudate) and salience processing (amygdala) might be hampered with high Disinhibition.

Real-time fMRI neurofeedback is a feasible tool to learn the volitional regulation of brain activity. So far, most studies provide continuous feedback information that is presented upon every volume acquisition. Although this maximizes the temporal resolution of feedback information, it may be accompanied by some disadvantages. Participants can be distracted from the regulation task due to (1) the intrinsic delay of the hemodynamic response and associated feedback and (2) limited cognitive resources available to simultaneously evaluate feedback information and stay engaged with the task. Here, we systematically investigate differences between groups presented with different variants of feedback (continuous vs. intermittent) and a control group receiving no feedback on their ability to regulate amygdala activity using positive memories and feelings. In contrast to the feedback groups, no learning effect was observed in the group without any feedback presentation. The group receiving intermittent feedback exhibited better amygdala regulation performance when compared with the group receiving continuous feedback. Behavioural measurements show that these effects were reflected in differences in task engagement. Overall, we not only demonstrate that the presentation of feedback is a prerequisite to learn volitional control of amygdala activity but also that intermittent feedback is superior to continuous feedback presentation.

Negotiation and trade typically require a mutual interaction while simultaneously resting in uncertainty which decision the partner ultimately will make at the end of the process. Assessing already during the negotiation in which direction one's counterpart tends would provide a tremendous advantage. Recently, neuroimaging techniques combined with multivariate pattern classification of the acquired data have made it possible to discriminate subjective states of mind on the basis of their neuronal activation signature. However, to enable an online-assessment of the participant's mind state both approaches need to be extended to a real-time technique. By combining real-time functional magnetic resonance imaging (fMRI) and online pattern classification techniques, we show that it is possible to predict human behavior during social interaction before the interacting partner communicates a specific decision. Average accuracy reached approximately 70% when we predicted online the decisions of volunteers playing the ultimatum game, a well-known paradigm in economic game theory. Our results demonstrate the successful online analysis of complex emotional and cognitive states using real-time fMRI, which will enable a major breakthrough for social fMRI by providing information about mental states of partners already during the mutual interaction. Interestingly, an additional whole brain classification across subjects confirmed the online results: anterior insula, ventral striatum, and lateral orbitofrontal cortex, known to act in emotional self-regulation and reward processing for adjustment of behavior, appeared to be strong determinants of later overt behavior in the ultimatum game. Using whole brain classification we were also able to discriminate between brain processes related to subjective emotional and motivational states and brain processes related to the evaluation of objective financial incentives.