Spatio‐temporal dynamics of oscillatory brain activity during the observation of actions and interactions between point‐light agents

Abstract

Predicting actions from non-verbal cues and using them to optimise one's response behaviour (i.e. interpersonal predictive coding) is essential in everyday social interactions. We aimed to investigate the neural correlates of different cognitive processes evolving over time during interpersonal predictive coding. Thirty-nine participants watched two agents depicted by moving point-light stimuli while an electroencephalogram (EEG) was recorded. One well-recognizable agent performed either a 'communicative' or an 'individual' action. The second agent either was blended into a cluster of noise dots (i.e. present) or was entirely replaced by noise dots (i.e. absent), which participants had to differentiate. EEG amplitude and coherence analyses for theta, alpha and beta frequency bands revealed a dynamic pattern unfolding over time: Watching communicative actions was associated with enhanced coupling within medial anterior regions involved in social and mentalising processes and with dorsolateral prefrontal activation indicating a higher

TMS-induced inhibition of the left premotor cortex modulates illusory social perception

“…In the other half of the trials, it was entirely replaced by noise dots (noise trials). The dots of agent B were presented using a limited life-time technique (for more detail, see Friedrich et al, 2022a, b; Manera et al, 2011b; Zillekens et al, 2019). The participants’ task was to indicate whether agent B was present or absent in the cluster of noise dots.…”

“…The participants’ task was to indicate whether they saw agent B in the cluster of noise dots or not. Previous studies using the same experimental design showed that communicative gestures, in contrast to individual actions, facilitated the perception of a second agent (Friedrich et al, 2022b; Manera et al, 2011b; Zillekens et al, 2019).…”

“…In this study, the premotor cortex was inhibited offline with cTBS, which means that a virtual lesions was set before the participants started with the experimental task and this virtual lesion should have lasted for the whole session (Huang et al, 2005). The experimental task is rather complex and each trial consists of different parts, which can be divided into three time segments (Friedrich et al, 2022b): First, participants were watching agent A's gesture and in case of a communicative gesture, they generated predictions for agent B's response action. Second, they focused on the cluster of noise dots and tried to detect agent B among them.…”

“…We used an experimental design developed by Manera and colleagues (2011b) including two point-light agents (Figure 1; Friedrich et al, 2022a, b; Manera et al, 2011b; Zillekens et al, 2019). The agents are humans represented by moving lights that are attached to their major joints.…”

“…(adapted from Friedrich et al, 2022a, b and Zillekens et al, 2019) . (A) Task conditions: Agent A performed either a communicative (COM) or an individual (IND) gesture.…”