Measuring the effect of affective stimuli on autonomic responses and task performance in a virtual environment by children with and without cerebral palsy

This study examined whether a functional virtual environment (VE) may be used to provide affective stimuli (AS) that lead to changes in the emotional responses and task performance of children with and without cerebral palsy (CP). Fifteen children with CP and 19 typically developing (TD) peers (6 to 12 years) prepared seven virtual meals in a predefined order within a virtual meal-making VE, referred to as the Emotional Meal-Maker (EMM), run on a 2D video capture VR platform. During each of six meals either a negative, positive, or neutral visual stimulus, selected from the International Affective Picture System (IAPS), was displayed. Heart rate (HR) and skin conductance (SCR) were recorded online in synchrony with stimulus onset. These variables were also recorded when the children passively viewed the same sequence of affective pictures displayed onscreen while rating their valence and arousal levels. Autonomic responses were calculated as the amount of change in the autonomic variables compared to baseline. Correlations between behavioural characteristics (i.e., trait and state anxiety) with both autonomic responses and task performance were also calculated. Significant differences were found between groups in task performance and heart rate variability (HRV) components, i.e., a higher “low frequency” (LF) to “high frequency” (HF) ratio in the children with CP during the meals in which a negative stimulus was displayed (U= 59.00, p= 0.011) and during the passive visual display, regardless of type of stimulus. For children with CP, the amplitude of skin conductance response during the passive pictures display was significantly higher for negative stimuli (0.80 ± 0.46 μS) than for positive stimuli (0.52 ± 0.28; Z= -2.38, p= 0.017), but there were no significant changes in autonomic responses as a function of stimuli during meal-making. Positive correlations were found in the CP group between trait anxiety and the LF:HF ratio during virtual meal-making with positive (p< 0.05) and negative stimuli (p<0.01) but not during meals when stimuli were neutral. The implications of these results are discussed.