How learning to shake a rattle affects 8-month-old infants’ perception of the rattle's sound: Electrophysiological evidence for action-effect binding in infancy

Abstract

Bidirectional action-effect associations play a fundamental role in intentional action control and the development of the mirror neuron system. However, it has been questioned if infants are able to acquire bidirectional action-effect associations (i.e., are able to intentionally control their actions). To investigate this, we trained 8-month-old infants for one week to use a novel rattle that produced a specific sound when shaken. Infants were also presented with another sound, which was not related to an action. Thereafter, infants' EEG responses to these two sounds and to an additional, unfamiliar sound were recorded. Infants displayed a stronger mu-desynchronization above cortical motor sites (i.e., motor resonance) when listening to the action-related sound than when hearing other sounds. Our results provide therefore electrophysiological evidence that infants as young as 8 months are able to acquire bidirectional action-effect associations and parallel findings of audiovisual mirror neurons in the monkey brain.

What are you doing? How active and observational experience shape infants' action understanding

“…This suggests that young infants readily acquire new sensorimotor associations and speaks to the flexibility of the developing mirror system [86].…”

“…[84,85]). Through repeated execution of actions, infants form associations between these motor acts and their sensory consequences [86]. When infants subsequently observe these actions in others, they can use their motor system to predict the outcome of the ongoing actions.…”

First-person action experience reveals sensitivity to action efficiency in prereaching infants

“…By this hypothesis, visuomotor "mirror" representations-which could be innate (18,19) or built from correlated sensory and motor action input (20,21)-allow for the activation of a corresponding motor program following perception of another's action. Spreading activation from the motor plan to a representation of the action's salient visual or auditory effects then allows the observer to categorize the observed action as directed toward that effect or end state (22,23). Neurons in macaque inferior parietal lobule that are tuned to the end goal of an observed…”

“…Context-specificity can be incorporated in an ideomotor model by assuming that actioneffect relationships are learned in a state-dependent manner (22). However, although a store of such contingencies could eventually support context-sensitive action interpretation, this learning would require large corpora of action statistics wherein the action-effect pairings are learned separately under each possible environmental state.…”

Which way to take? Infants select an efficient path to their goal

“…The intention to elicit a particular sensory effect is assumed to activate directly the motor program associated with this effect, thereby leading to intentional action selection. Importantly, infant studies have demonstrated the presence of action-effect associations already in 1-year-olds (e.g., Elsner & Aschersleben, 2003;Kenward, 2010;Paulus, Hunnius, Van Elk, & Bekkering, 2012;Verschoor, Paulus, Spape, Biro, & Hommel, 2015;Verschoor, Weidema, Biro, & Hommel, 2010). Yet, the findings of infants' flexible means selection in Experiment 2, particularly their ability to switch to a formerly not used means to attain a goal that was previously attained by another means, seem to go beyond action-effect associations as a mechanism underlying efficient action selection.…”