Processing of Hand-Related Verbs Specifically Affects the Planning and Execution of Arm Reaching Movements

Abstract

Even though a growing body of research has shown that the processing of action language affects the planning and execution of motor acts, several aspects of this interaction are still hotly debated. The directionality (i.e. does understanding action-related language induce a facilitation or an interference with the corresponding action?), the time course, and the nature of the interaction (i.e. under what conditions does the phenomenon occur?) are largely unclear. To further explore this topic we exploited a go/no-go paradigm in which healthy participants were required to perform arm reaching movements toward a target when verbs expressing either hand or foot actions were shown, and to refrain from moving when abstract verbs were presented. We found that reaction times (RT) and percentages of errors increased when the verb involved the same effector used to give the response. This interference occurred very early, when the interval between verb presentation and the delivery of the go signal was 50 ms, and could be elicited until this delay was about 600 ms. In addition, RTs were faster when subjects used the right arm than when they used the left arm, suggesting that action–verb understanding is left-lateralized. Furthermore, when the color of the printed verb and not its meaning was the cue for movement execution the differences between RTs and error percentages between verb categories disappeared, unequivocally indicating that the phenomenon occurs only when the semantic content of a verb has to be retrieved. These results are compatible with the theory of embodied language, which hypothesizes that comprehending verbal descriptions of actions relies on an internal simulation of the sensory–motor experience of the action, and provide a new and detailed view of the interplay between action language and motor acts.

Are the motor features of verb meanings represented in the precentral motor cortices? Yes, but within the context of a flexible, multilevel architecture for conceptual knowledge

“…These studies, among many others (e.g., Sato et al, 2008;Mirabella et al, 2012;Aravena et al, 2012Aravena et al, , 2014, suggest that verb-induced motor activation is not a rigid, inflexible affair, but is instead sensitive to attentional and situational factors that we are only beginning to understand. It is essential to realize, however, that the mere fact that there is some variability regarding when and how the motor features of verb meanings are retrieved does not imply that those features are not really long-term components of the concepts or that they are not really subserved by the precentral motor cortices.…”

How the context matters. Literal and figurative meaning in the embodied language paradigm

“…An interference effect has also been observed in another set of studies (e.g. [8,[10][11][12][13]). The occurrence of either facilitation or interference is thought to depend on the extent of the temporal overlapping between linguistic and motor tasks [10,12,14].…”

Language–motor interference reflected in MEG beta oscillations

“…The reason to initially include imageability as an experimental factor was not an expected interaction with the interference effect based on the literature (Sato et al, 2008;Mirabella et al, 2012;Buccino et al, 2005). Rather, this factor was introduced to control for its facilitatory influence on reaction times (Giesbrecht et al, 2004;Newcombe et al, 2012) since our set of stimuli is characterised by a larger variability of imageability than reported in previous experiments (Mirabella et al, 2012).…”

“…Evidence for language-motor interaction was found in a range of behavioural experiments (Bergen et al, 2010;Boulenger et al, 2006;Hirschfeld and Zwitserlood, 2012;Glenberg and Kaschak, 2002); as well as neurophysiological experiments Willems et al, 2011). Language processing can influence motor behaviour kinematics (Dalla Volta et al, 2009;Mirabella et al, 2012;Nazir et al, 2008) or reaction times (Liepelt et al, 2012;Buccino et al, 2005). Generally, the interaction between language and motor tasks can either produce interference or facilitation, depending on the respective task and situational factors such as stimulus timing or stimulus set (Paulus et al, 2009;Chersi et al, 2010;Diefenbach et al, 2013;de Vega et al, 2013).…”