Differences in autonomic functions as related to induced stress between children with and without cerebral palsy while performing a virtual meal-making task

Abstract

Background: Efforts to improve the participation and performance of children with cerebral palsy (CP) are often related to the adaptation of environmental conditions to meet their cognitive and motor abilities. However, the influence of affective stimuli within the environment on emotion and performance, and their ability to improve or impede the children's participation has not been investigated in any systematic way although the emerging evidence suggests that it affects the individuals in many levels.

Objectives: (1) To measure autonomic responses to affective stimuli during a simulated Meal-Maker task in children with CP in comparison to children who are typically developing, and (2) to examine the interactions between autonomic functions, subjective reports of stress, and task performance among children with and without CP.

Methods: Fifteen children with CP and 19 typically developing peers (6 to 12 years) participated. After completing behavioral questionnaires (e.g., State and Trait Anxiety Inventories), children prepared meals within a camera tracking virtual Meal-Maker environment. Either a negative, positive, or neutral visual stimulus was displayed, selected from the International Affective Picture System. Children also passively viewed the same pictures while rating their valence and arousal levels. Heart rate (HR) and skin conductance were recorded synchronously with stimulus onset.

Results: Significant differences in autonomic functions were found between groups, i.e., a higher "low frequency" to "high frequency" (LF:HF) ratio in the children with CP during the meals associated with a negative stimulus (p=0.011). Only children with CP had significant positive correlations between trait anxiety and LF:HF ratio during virtual meal-making associated with positive (p=0.049) and negative stimuli (p=0.003) but not during neutral stimuli. For children with CP the amplitude of skin conductance response during passive picture viewing was significantly higher for negative than for positive stimuli (p=0.017) but there were no significant changes in autonomic responses during virtual Meal-Maker task. Significant correlations between trait anxiety, autonomic activity during the calm state and Meal-Maker performance outcomes were found only for children with CP.

Conclusions: In general, the Meal-Maker virtual environment was shown to be a feasible platform for the investigation of the effect of emotionally loaded stimuli on the balance of autonomic functions in children with and without CP. Anxiety level appears to play a significant role in children with CP and should be considered as a potentially important factor during clinical evaluation and intervention. Further studies are needed to develop additional measurements of emotional responses and to refine the types of affective interference.

Keywords: Affective stimuli; Autonomic functions; Cerebral palsy; Virtual reality.