Unusual actions do not always trigger the mentalizing network

Abstract

Past fMRI research has demonstrated that to understand other people's behavior shown visually, the mirror network is strongly involved. However, the mentalizing network is also recruited when a visually presented action is unusual and/or when perceivers think explicitly about the intention. To further explore the conditions that trigger mentalizing activity, we replicated one of such studies (de Lange, Spronk, Willems, Toni, & Bekkering, 2008, Current Biology, 18, 454) under the minimal instruction to "view" pictures of unusual actions, without giving any "intention" instruction as in the original study. Contrary to earlier research, merely viewing unusual actions did not activate mentalizing areas. Instead, the dorsal anterior cingulate cortex was activated. We conclude that unusual actions are not sufficient by themselves to trigger mentalizing. In order to activate the mentalizing network without an intention instruction, a richer action context informative of the implausibility of the action might be a prerequisite.

Perceiving Hesitation requires both the Motor and Mentalizing systems

“…A small number of studies corroborate our fMRI findings by using photos or movies of actions as stimuli and observed both networks to be co-activated, namely while judging the meaning of gestures (Schippers et al 2010), the confidence of an informant from facial movements (Kuhlen et al 2015), and while judging why participants perform certain hand actions (de Lange et al 2008;Spunt et al 2011;Ampe et al 2014). Co-activation were also found, when participants observed actions directed at another person as compared to solo actions (Centelles et al 2011;Becchio et al 2012).…”

“…Nonetheless, several studies have reported increases of activity in the mentalizing network while subjects watched actions performed by a protagonist. Results of these studies suggest that increases of activity or connectivity in the mentalizing system is found when participants watch interactive or communicative gestures (Schippers et al 2009;Centelles et al 2011;Becchio et al 2012;Mainieri et al 2013;Ciaramidaro et al 2014;Sperduti et al 2014) when watching irrational actions in relation to the context (Brass et al 2007;Jastorff et al 2011; but see Liew et al 2011;Ampe et al 2014) or when simply paying attention to why an action is performed (Brunet et al 2000;Grèzes et al 2004;de Lange et al 2008;Spunt et al 2011;Chambon et al 2017) This tension between studies emphasizing the independence of these two networks and those reporting co-activation raises the question of what determines whether observed actions recruit the theory of mind network. Several attempts have been made to describe the different levels of representations involved in actions, and these distinctions might be relevant here.…”

Responses to irrational actions in action observation and mentalising networks of the human brain

“…In the same study, IFG responded when participants viewed actions with unusual goals, demonstrating the complementary roles of action observation and mentalising systems. However, in these studies the engagement of the AON and MZN is dependent upon instructions to think about different aspects of the stimuli (see Ampe et al, 2012) and may not reflect spontaneous action understanding. Two recent studies have shown that the AON and MZN are both active during observation of simple grasping actions with social (Becchio et al, 2012) or communicative (Ciaramidaro et al, 2014) intent.…”

When context modulates the influence of action observation on language processing

“…This led us to question specifically the role of the context on the link between action observation and action verbs processing. We know that actions are considered “usual” only when they are presented in a typical and expected context, whereas actions that do not fit a given context are labelled “unusual” [ 16 ]. It has been demonstrated that the perception of unusual actions does not activate the same cerebral areas as the perception of usual actions [ 17 ].…”