Prefrontal cortex activation in preschoolers’ naturalistic action sequence planning

• In Event: Infant learning and brain development

Abstract

Brain activation patterns of young toddlers and children are difficult to investigate as children rarely comply with the restrictions of neuroimaging testing (i.e. sitting still, long repetitions of trials). Furthermore, to understand the brain development of real-world functions such as planning and executive functions, it is crucial to have ecologically-valid tasks (Pinti et al., 2018). The aims of this study were: 1) to assess the feasibility of wireless fNIRS in combination with optical motion capture to investigate neural development of planning and executive functions in preschoolers in freely moving children, and 2) to investigate changes in prefrontal cortex activation in action sequence planning in the preschool period.

Forty-five 3-year-olds (40±3months, 27F) and 47 5-year-olds (64±4months, 20F) were instructed to build a Duplo house with a goal hierarchy to assess naturalistic action sequence planning (Schröer et al., 2021). Furthermore, children performed a computer-based block-design Go/No-Go inhibition task as control task. We included a multimodal set-up with 1) a 46-channel wireless fNIRS system (Brite24, Artinis Medical Systems BV) to measure changes in cortical haemodynamics over prefrontal and motor cortex bilaterally, and 2) optical motion capture (Vicon Systems) to track movement kinematics of hands and behaviour in this naturalistic task (Figure 1).

Behavioural data of the Duplo task was coded to recover the timeline of events. fNIRS signals were pre-processed to reduce motion artifacts and physiological noise. An event-related general linear model analysis was used to contrast brain activation patterns at branch points when children switched from one subgoal to another to within-subtask steps when the child remained in the same subgoal. Preliminarily analysis on 30 participants showed that there was a significant amplitude change in oxy-hemoglobin in the inhibition task in the left DLPFC only in 5-year-olds, suggesting that our set-up allows us to measure executive functions and planning in preschoolers in standard computer-based tasks. More interestingly, in the naturalistic planning task, there was a significant decrease in oxy-hemoglobin in the right homolog to Broca’s area and a decrease in deoxy-hemoglobin in the right DLPFC at branch points in 5-year-olds (Figure 2). This effect was absent in 3-year-olds.

Our findings suggest that good quality fNIRS data can be recorded from freely moving preschoolers in naturalistic tasks, with a decrease in deoxy-hemoglobin observed in right DLPFC at branch points in action sequence planning. The multi-modal set-up including motion capture allows us to reconstruct the timeline of events of interest. This study provides the first evidence of the feasibility of multimodal wearables in freely moving preschoolers to investigate the development of planning and executive functions in naturalistic settings.

Authors

• Lisanne Schroer, Erasmus University Rotterdam
  Presenting Author

• Paola Pinti, Birkbeck, University of London

• Richard P. Cooper, Birkbeck, University of London

• Denis Mareschal, Birkbeck, Universty of London