Comparing cutaneous sensory reactivity between children with and without global developmental delay

Abstract

Our scientific understanding of pain among individuals with developmental delays and disabilities with associated intellectual, motor, and/or communicative impairments is limited because of the difficulty in reliably and validly assessing a complex experience when verbal self-report is compromised. One approach is to rely on non-verbal pain behaviors. There has been no work comparing non-verbal pain behavior of very young children with global developmental delays with age and gender matched typically developing children. This study used a calibrated tactile sensory test to provide a mechanisms-based approach to indirectly compare the functionality of the somatosensory pathways in children with and without global developmental delay (GDD). A case control design was used to test the reactivity of 20 children with GDD (60% male; M age = 4.91 years, SD=1.13) and 20 typically developing children (60% male; M age = 3.49 years, SD=1.08). Sensory reactivity was indexed by vocal, facial, and body activity during the sensory test. This sample of children with GDD exhibited significantly greater duration of overall reactivity during the sensory test (p<.01) and specifically exhibited greater vocal (p<.01) and body (p<.05) reactivity compared to controls. For children with GDD, severity of self-injurious behavior significantly correlated with vocal (r=.58, p=.01) and body (r=.56, p<.05) reactivity during the pin prick trial. Children with GDD who were more reactive to the sensory test had significantly reduced epidermal nerve fiber densities (p<.05). This study was the first to measure the behavioral response of children with GDD to a calibrated sensory test and in comparison to a typically developing control group. The results of the study provide information about the physiology and nociceptive pathways of children with GDD. Despite limitations in verbal self-report, children with GDD exhibited non-verbal pain behaviors to signal their reactivity to a calibrated sensory test.