The role of the right tempoparietal junction in the elicitation of vicarious experiences and detection accuracy while observing pain and touch

This study investigated the effects of observing pain and touch in others upon vicarious somatosensory experiences and the detection of subtle somatosensory stimuli. Furthermore, transcranial direct current stimulation (tDCS) was used to assess the role of the right temporoparietal junction (rTPJ), as this brain region has been suggested to be involved in perspective taking and self-other distinction. Undergraduates (N = 22) viewed videos depicting hands being touched, hands being pricked, and control scenes (same approaching movement as in the other video categories but without the painful/touching object), while experiencing vibrotactile stimuli themselves on the left, right, or both hands. Participants reported the location at which they felt a somatosensory stimulus. Vibrotactile stimuli and visual scenes were applied in a congruent or incongruent way. During three separate testing sessions, excitability of the rTPJ was modulated with tDCS (cathodal, anodal, or sham). We calculated the proportion of correct responses and false alarms (i.e., number of trials in which a vicarious somatosensory experience was reported congruent to the site of the visual information). Pain-related scenes facilitated the correct detection of tactile stimuli and augmented the number of vicarious somatosensory experiences compared with observing touch or control videos. Stimulation of the rTPJ had no reliable influence upon detection accuracy or the number of vicarious errors. This study indicates that the observation of pain-related scenes compared to the observation of touch or control videos increases the likelihood that a somatosensory stimulus is detected. Contrary to our expectations, the rTPJ did not modulate detection accuracy

It wasn't me! Motor activation from irrelevant spatial information in the absence of a response

Embodied cognition postulates that perceptual and motor processes serve higher-order cognitive faculties like language. A major challenge for embodied cognition concerns the grounding of abstract concepts. Here we zoom in on abstract spatial concepts and ask the question to what extent the sensorimotor system is involved in processing these. Most of the empirical support in favor of an embodied perspective on (abstract) spatial information has derived from so-called compatibility effects in which a task-irrelevant feature either facilitates (for compatible trials) or hinders (in incompatible trials) responding to the task-relevant feature. This type of effect has been interpreted in terms of (task-irrelevant) feature-induced response activation. The problem with such approach is that incompatible features generate an array of task relevant and irrelevant activations [e.g., in primary motor cortex (M1)], and lateral hemispheric interactions render it difficult to assign credit to the task-irrelevant feature per se in driving these activations. Here, we aim to obtain a cleaner indication of response activation on the basis of abstract spatial information. We employed transcranial magnetic stimulation (TMS) to probe response activation of effectors in response to semantic, task-irrelevant stimuli (i.e., the words left and right) that did not require an overt response. Results revealed larger motor evoked potentials (MEPs) for the right (left) index finger when the word right (left) was presented. Our findings provide support for the grounding of abstract spatial concepts in the sensorimotor system

Anticipating actions and corticospinal excitability : a preregistered motor TMS experiment

Past research on action observation and imitation suggests that observing a movement activates a corresponding motor representation in the observer. However, recent research suggests that individuals may not only reflexively simulate the observed behavior but also simulate and engage in anticipated action without another person actually engaging in it. For example, it has been demonstrated that observing a triggering event (i.e., nose wrinkling) that potentially leads to the anticipation of an action (i.e., nose scratching) increases the likelihood that the observer will perform that action. In the present research, we applied motor Transcranial Magnetic Stimulation (TMS) to investigate such anticipated social action effects at the neurophysiological level within a trial-by-trial measure. While a pilot study suggests that observing nose wrinkling elicits stronger motor evoked potentials (MEPs) in participants' biceps muscles than observing control events, this effect could not be fully replicated in a preregistered study. Although a post hoc meta-analysis across both studies supports the general hypothesis, these results need to be taken cautiously. Implications of the results reported in the manuscript are discussed. (C) 2018 Elsevier Ltd. All rights reserved

Spontaneous theory of mind is reduced for nonhuman-like agents as compared to human-like agents

Theory of Mind research has shown that we spontaneously take into account other's beliefs. In the current study, we investigate, with a spontaneous Theory of Mind (ToM) task, if this belief representation also applies to nonhuman-like agents. In a series of three experiments, we show here that we do not spontaneously take into account beliefs of nonhuman-like others, or at least we do it to a lesser extent than for human and human-like agents. Further, the experience we have with the other agent, in our case a dog, does not modulate spontaneous ToM: the same pattern of results was obtained when dog owners and no owners were compared. However, when more attention was attracted to the dog behavior, participants' behavior was influenced by the beliefs of the dog. In sum, spontaneous belief representation seems to be primarily restricted to human and human-like agents, but can be facilitated when more attention is drawn to a nonhuman-like agent

Mimicry and automatic imitation are not correlated

It is widely known that individuals have a tendency to imitate each other. However, different psychological disciplines assess imitation in different manners. While social psychologists assess mimicry by means of action observation, cognitive psychologists assess automatic imitation with reaction time based measures on a trial-by-trial basis. Although these methods differ in crucial methodological aspects, both phenomena are assumed to rely on similar underlying mechanisms. This raises the fundamental question whether mimicry and automatic imitation are actually correlated. In the present research we assessed both phenomena and did not find a meaningful correlation. Moreover, personality traits such as empathy, autism traits, and traits related to self- versus other-focus did not correlate with mimicry or automatic imitation either. Theoretical implications are discussed

The role of stimulus-driven versus goal-directed processes in fight and flight tendencies measured with motor evoked potentials induced by Transcranial Magnetic Stimulation

This study examines two contrasting explanations for early tendencies to fight and flee. According to a stimulus-driven explanation, goal-incompatible stimuli that are easy/difficult to control lead to the tendency to fight/flee. According to a goal-directed explanation, on the other hand, the tendency to fight/flee occurs when the expected utility of fighting/fleeing is the highest. Participants did a computer task in which they were confronted with goal-incompatible stimuli that were (a) easy to control and fighting had the highest expected utility, (b) easy to control and fleeing had the highest expected utility, and (c) difficult to control and fleeing and fighting had zero expected utility. After participants were trained to use one hand to fight and another hand to flee, they either had to choose a response or merely observe the stimuli. During the observation trials, single-pulse Transcranial Magnetic Stimulation (TMS) was applied to the primary motor cortex 450 ms post-stimulus onset and motor evoked potentials (MEPs) were measured from the hand muscles. Results showed that participants chose to fight/flee when the expected utility of fighting/fleeing was the highest, and that they responded late when the expected utility of both responses was low. They also showed larger MEPs for the right/left hand when the expected utility of fighting/fleeing was the highest. This result can be interpreted as support for the goal-directed account, but only if it is assumed that we were unable to override the presumed natural mapping between hand (right/left) and response (fight/flight)

Measuring mentalizing ability: a within- subject comparison between an explicit and implicit version of a ball detection task

The concept of mentalizing has been widely studied, but almost exclusively through tasks with explicit instructions. Recent studies suggest that people also mentalize on a more implicit level. However, to our knowledge, no study to date has directly contrasted the effects of implicit and explicit mentalizing processes on an implicit dependent measure within-subjects. We implemented this by using two versions of an object detection task, differing only on secondary catch questions. We hypothesized that if explicit mentalizing relies on complementary processes beyond those underlying implicit mentalizing, this would be reflected in enhanced belief effects in the explicit version. Twenty-eight healthy adults watched movies in which, during the first phase, both they themselves and another agent formed a belief about the location of a ball, and although irrelevant, these beliefs could influence their ball detection reaction times in the second phase. After this response phase, there were occasional catch questions that were different for the explicit and implicit task version. Finally, self-report measures of autism spectrum disorder (ASD) symptomatology were included, as the literature suggests that ASD is related to a specific deficit in implicit mentalizing. Both in the explicit and implicit version, belief conditions had a significant effect on reaction times, with responses being slower when neither the participant nor the other agent expected the ball to be present compared to all other conditions. Importantly, after the implicit version, participants reported no explicit mentalizing awareness. In our neurotypical sample, ASD symptoms were not found to correlate with either explicit or implicit mentalizing. In conclusion, the reaction time patterns in the explicit and implicit version of the task show strikingly similar effects of mentalizing, indicating that participants processed beliefs to the same extent regardless of whether they mentalized explicitly or implicitly, with no additional effects for explicit processing

Support from a TMS/MEP study for a direct link between positive/negative stimuli and approach/avoidance tendencies

International audienc

Measuring spontaneous mentalizing with a ball detection task : putting the attention-check hypothesis by Phillips and colleagues (2015) to the test

Theory of Mind (ToM) or mentalizing refers to the ability to attribute mental states (such as desires, beliefs or intentions) to oneself or others. ToM has been argued to operate in an explicit and an implicit or a spontaneous way. In their influential paper, Kovács et al. (Science 330:1830–1834, 2010) introduced an adapted false belief task—a ball detection task—for the measurement of spontaneous ToM. Since then, several studies have successfully used versions of this paradigm to investigate spontaneous ToM. This paradigm has, however, been criticized by Phillips et al. (Psychol Sci 26(9):1353–1367, 2015), who argue that the effects are fully explained by timing artifacts in the paradigm, namely differences in timing of the attention check. The main objective of the current study is to test this attention-check hypothesis. An additional aim was to relate the findings to autism spectrum disorder (ASD) symptomatology in our neurotypical sample, as ASD has been linked to deficits in spontaneous mentalizing. We applied an adjusted version of the paradigm in which the timings for all conditions are equalized, ruling out any potential timing confounds. We found significant main effects of own and agent beliefs on reaction times. Additionally, we found a significant ‘ToM-effect’: When participants believe the ball is absent, they detect the ball faster if the agent believes the ball would be present rather than absent, which refers to the original effect in the paper of Kovács et al. (2010), taken as evidence for spontaneous ToM and which was contested by Phillips et al. (2015). Our findings cannot be explained by the attention-check hypothesis. Effects could not be associated with ASD symptoms in our neurotypical sample, warranting further investigation on the link between spontaneous mentalizing and ASD