Playing with temptation: Stopping abilities to chocolate are superior, but also more extensive.

Cue-specific inhibitory control is assumed to support balanced food intake, but previous studies with established measures showed inconsistent results. We developed a novel kinematic stop task in virtual reality (VR) and report results from trajectory recordings. The primary objective of this explorative study was to assess the interrelationships between validated measures of food-related inhibitory control and novel measures from the VR task. We hypothesized that healthy female participants show worse inhibitory control when grasping attractive virtual chocolate, compared to non-edible color-and-shape matched objects. We further aimed to quantify the construct validity of kinematic measures (e.g., reaching extent/spatial displacement, movement time after stop-signal, velocity) with established measures of inhibitory control in a keyboard-based adaptive stop-signal task (SST). In total, 79 females with varying levels of chocolate craving participated in an experimental study consisting of self-report questionnaires, subjective chocolate craving, the conventional SST and the kinematic task in VR. Results showed superior stopping ability to chocolate in both tasks. In VR, participants successfully interrupted an initiated approach trajectory but terminated slightly closer to chocolate targets. Stop-signal delay (SSD) was adapted relative to movement onset and appeared later in chocolate trials, during which participants still stopped faster, as was also confirmed by shorter stop-signal reaction time (SSRT) in the conventional task. Yet, SSRT did not correlate with stopping in VR. Moreover, SSRT was related to depressive symptoms whereas measures from VR were related to chocolate craving and subjective hunger. Thus, VR stopping can provide deeper insights into healthy weight individuals' capacity to inhibit cue-specific approach behavior towards appetitive stimuli in simulated interactions. Furthermore, the results support a multi-faceted view of food-specific inhibitory control and behavioral impulsivity.

Polarity Specific Effects of Cross-Hemispheric tDCS Coupled With Approach-Avoidance Training on Chocolate Craving.

Transcranial Direct Current Stimulation (tDCS) over the Dorsolateral Prefrontal Cortex (DLPFC) has already been shown to decrease craving for food. However, it remains unclear whether a single session of tDCS combined with a cognitive bias modification (CBM) task may affect explicit and implicit measures of craving for chocolate. Fifty-one healthy volunteers (38 females; mean age: 22.12 ± 3.38) were randomly allocated to CBM training based on the Approach Avoidance task and either Sham, Right anodal-Left cathodal (RALC), or Left anodal-Right cathodal (LARC) tDCS. Results show that there was an increase in the explicit craving for chocolate, as assessed by the Visual Analog Scale [F(2, 46) = 3.239, p = 0.048], from the baseline to post-intervention. Participants which received LARC tDCS were explicitly self-reporting more craving for chocolate than those that received RALC tDCS (p = 0.023). Moreover, this effect was also observed on the implicit measure [F(2, 46) = 4.168, p = 0.022]. LARC tDCS significantly increased the implicit preference for chocolate when comparing to both RALC (p = 0.009) and Sham tDCS (p = 0.034). Previous studies have shown that RALC tDCS over the PFC is able to effectively decrease craving for food. Interestingly, the present data not only does not reproduce such result, but instead it suggests that LARC tDCS can actually increase the preference for chocolate. This result is compatible with recent models of brain laterality, in which cue craving seems to be more dependent on the left hemisphere. Thus, shifting the activity to the left hemisphere (while simultaneously reducing the activity over the homotopic region) may have led to this increased implicit as well as explicit preference for chocolate.

Chocolate craving and disordered eating. Beyond the gender divide?

Chocolate craving in women has previously been linked to disordered eating behaviors. A relatively higher prevalence of eating disorder pathology may account for the fact that chocolate craving is significantly more common in women in North America, compared to many other countries. While support for a causal role of disordered eating in the etiology of craving in women is growing, little is known about the extent to which food cravings are associated with disordered eating behaviors in men. This study was designed to systematically assess the impact of gender and chocolate craving on measures of attitudes to chocolate, responsiveness to food cues in the environment, body shape dissatisfaction, dietary restraint, and eating disorder and general pathology. Undergraduate men and women (n = 645, 37.2% male) were invited to complete self-report questionnaires assessing demographics, height and weight, food cravings, dietary attitudes and behaviors, along with eating disorder and general pathology. Data suggest that the relationship between chocolate craving and disordered eating behaviors in men is the opposite of what has previously been observed in women: compared to non-cravers, male chocolate cravers reported significantly more guilt related to craving, but were significantly less likely to diet and reported lower levels of dietary restraint, less frequent weight fluctuations, and fewer symptoms of eating disorders. Findings indicate that a positive relationship between disordered eating behaviors and chocolate craving may be unique to women (and potentially women in North America). Findings have important implications for our understanding of cultural and psychosocial factors involved in the etiology of food cravings.