Visible skin disease symptoms of another person reduce automatic imitation of their hand movements.

Imitation is an important mechanism for social interaction and learning, and humans tend to imitate others automatically. While imitating others is often useful, it can backfire when imitation is incongruent with one's goals. For example, in forced-choice reaction time tasks, this tendency results in a reliable slowing of reactions if the observed and self-initiated actions are incompatible (compatibility effect). While imitation is commonly explained as a social phenomenon, previous results on the compatibility effect's dependence on social cues are inconsistent. However, in many previous studies, the associated social cues were easy to ignore by the participants. To make the social modifier more salient, the current study manipulated emotionally relevant aspects of the model hand itself in an imitation inhibition task by using models displaying skin disease symptoms which we expected to elicit (1) perceptions of dissimilarity and (2) disgust in participants. As predicted, participants' (n = 63) reaction times were influenced more by the incompatible actions of the symptom-free than the symptomatic model hand. However, both levels of self-reported disgust toward and self-other overlap with symptomatic hands were low and did not account for the observed effect on automatic imitation. Our findings show that automatic imitation depends on social factors if these are an integral part of the model and processed quickly, presumably due to their affective salience or the salience of the self-other distinction. Whether this effect is driven by emotional reactions to the model remains an open question.

Anticipation of aversive visual stimuli lengthens perceived temporal duration.

Subjective estimates of elapsed time are sensitive to the fluctuations in an emotional state. While it is well known that dangerous and threatening situations, such as electric shocks or loud noises, are perceived as lasting longer than safe events, it remains unclear whether anticipating a threatening event speeds up or slows down subjective time and what defines the direction of the distortion. We examined whether the anticipation of uncertain visual aversive events resulted in either underestimation or overestimation of perceived duration. The participants did a temporal bisection task, where they estimated durations of visual cues relative to previously learnt long and short standard durations. The colour of the to-be-timed visual cue signalled either a 50% or 0% probability of encountering an aversive image at the end of the interval. The cue durations were found to be overestimated due to anticipation of aversive images, even when no image was shown afterwards. Moreover, the overestimation was more pronounced in people who reported feeling more anxious while anticipating the image. These results demonstrate that anxiogenic anticipation of uncertain visual threats induce temporal overestimation, which questions a recently proposed view that temporal underestimation evoked by uncertain threats is due to anxiety.

Increasing self-other similarity modulates ethnic bias in sensorimotor resonance to others' pain.

The tendency to simulate the pain of others within our own sensorimotor systems is a vital component of empathy. However, this sensorimotor resonance is modulated by a multitude of social factors including similarity in bodily appearance, e.g. skin colour. The current study investigated whether increasing self-other similarity via virtual transfer to another colour body reduced ingroup bias in sensorimotor resonance. A sample of 58 white participants was momentarily transferred to either a black or a white body using virtual reality technology. We then employed electroencephalography to examine event-related desynchronization (ERD) in the sensorimotor beta (13-23 Hz) oscillations while they viewed black, white and violet photorealistic virtual agents being touched with a noxious or soft object. While the noxious treatment of a violet agent did not increase beta ERD, amplified beta ERD in response to black agent's noxious vs soft treatment was found in perceivers transferred to a black body. Transfer to the white body dismissed the effect. Further exploratory analysis implied that the pain-related beta ERD occurred only when the agent and the participant were of the same colour. The results suggest that even short-lasting changes in bodily resemblance can modulate sensorimotor resonance to others' perceived pain.

No evidence of calorie-related modulation of N2 in food-related Go/No-Go training: A preregistered ERP study.

Go/No-Go tasks, which require participants to inhibit automatic responses to images of palatable foods, have shown diagnostic value in quantifying food-related impulses. Moreover, they have shown potential for training to control impulsive eating. To test the hypothesis that training modulates early neural markers of response inhibition, the current study investigated how the N2 event-related brain potential to high- and low-calorie food images changes along Go-/No-Go training and how the N2 is related to later eating behavior. 50 healthy adults, (mBMI  = 23.01) first completed a food Go/No-Go task in which high- and low-calorie food images were accompanied by Go-and No-Go-cues with equal frequency. Participants then completed a training block in which high-calorie foods were predominantly paired with a No-Go cue and the low-calorie foods with a Go cue, followed by a block with reversed coupling (order of the training blocks counterbalanced between participants). After each training, there was a snacking opportunity during which calorie intake was measured. Against our preregistered hypotheses, the N2-amplitudes were not significantly affected by the calorie-content and there was no training-related modulation in the N2. In addition , food intake was not influenced by the preceding training blocks and the N2 amplitude did not predict the food intake. Our study suggests that the link between N2 obtained in a food-related Go/No-Go task and impulse control is not clear-cut and may be limited to specific task characteristics. The results are of high importance as they question the previously assumed mechanism of Go/No-Go training in food-related inhibitory control.