Isolating Action-specific Neural Response During Observation of Motorically Familiar and Unfamiliar Action in Infancy

• In Event: Poster Session 05
  In Poster Session: PS 05 Topic - Biological Processes: Neuroscience and Genetics

Abstract

Action production and perception lead to overlapping neural motor activation (neural mirroring), suggested to serve as a basis for action understanding. Recent evidence shows that neural mirroring is tightly associated with actions in which infants are competent in (Cannon et al., 2016). Others find neural mirroring extends even to actions beyond one’s motor repertoire (Southgate & Begus, 2013), challenging the notion that experience is critical in neural mirroring. This apparent contradiction in findings may stem from the decision of baseline. Baselines that differ visually from observation windows may capture beyond motor activity contaminated with general visual processes. So far, however, neural mirroring studies in infancy have focused on analysis of Mu power (6-9Hz) calculated with the same type of baseline for different experimental observation with less emphasis on matching visual scene. Baselines that help distinguish motor processes from general visual alpha response will help understand contrary findings across studies. Moreover, having been focused solely on Mu power, the field has been neglecting other important aspects of the multidimensional neural signal with potential to resolve this discrepancy such as functional connectivity and it’s relation to behavior.

We aimed to expand our understanding of how active experience impacts action perception by exploring 9 month (N=17, M=9m20days) and 12-month-old(N=19, M=12m 21days) infants’ alpha power (6-9Hz) over Central and Occipital regions during observation of Grasp (motorically familiar) and Cane-use (unfamiliar) action. Our goal was to (1) compare neural mirroring with a baseline that is visually similar to each experimental window (visually-matched Baseline2, Figure1) to one that includes differences (Baseline1), (2) capture topographically isolated action-specific mirroring processes, (3) explore functional connectivity between different regions during observation, (4) and explore associations of alpha power with behavior.
(1) When using Baseline2, we found significantly less suppression of visual alpha. Also, we found significantly more mu suppression during observation of Grasp than Cane-use actions (during anticipation of the action). (2) Thus it allowed us to isolate the action-specific component from the neural signal. The opposite pattern was found for Baseline1. (3) In the Grasp condition, connectivity between central-occipital regions (M= 0.39, SE = 0.08) was significantly higher than central-frontal (M= 0.36, SE = 0.08, p= .015) and central-parietal (M= 0.36, SE = 0.07, p= .013). In the Cane-use condition, there was no evidence for a difference among connectivity across regions, though no evidence of an interaction between Condition and electrode clusters emerged. (4) We observed a marginally significant relation between Mu power regardless of baseline during observation of grasping actions and infants’ grasping latency, and this relation was specific to Mu power and not visual alpha. These findings are in line with the notion that experience influences infants’ action perception. Moreover, infant neural mirroring is evident in 9- and 12-month-olds yet heavily dependent on the baseline and need to be teased apart from visual processes. However, a comprehensive interpretation can be made with additional measures to isolate action-specific processes. Our findings contribute empirical evidence to methodological refinement that can be used to measure the infant neural mirroring network.

Authors

• Haerin Chung, University of Chicago
  Presenting Author

• Marlene Meyer, Radboud Universiteit Nijmegen
  Non-Presenting Author

• Rebecca Wixted
  Non-Presenting Author

• Christina Hartman, University of Chicago
  Non-Presenting Author

• Amanda Woodward, University of Chicago
  Non-Presenting Author