Objective: Sensory modulation disorder (SMD) is a generalised disorder that affects the modulation of sensory input across different modalities. Children with SMD are characterised by an abnormal processing of the sensory-discriminative and affective-aversive attributes of naturally occurring stimuli and are limited in their ability to participate fully and attain optimal quality of life. Approximately 5% of the paediatric population in the USA demonstrate over or underresponsiveness to sensory stimuli that is severely maladaptive, interfering with their daily life functions. Our aim in this study was to phenotype children with SMD psychophysically using low and high mechanical tactile stimulation.
Method: Using the short sensory profile followed by the sensory profile, 44 children were diagnosed as having SMD (33 boys and 11 girls on average 7.5 years old (SD 1.20 months)) and 34 as SMD-free (18 boys and 16 girls, 7.67 years old (SD 1.33 months)). All participants underwent tests to determine the detection and tolerance thresholds to warm, hot, cold, light touch, vibration, prickliness and pinprick stimuli.
Results: We found no differences between the groups in the detection thresholds of vibration, light touch, warm stimuli and pain thresholds of heat and cold stimuli. However, significant group differences were found for the detection of cold stimuli. The groups also differed significantly in the level of pain elicited in response to punctate tests.
Conclusion: This is the first psychophysical assessment of children with SMD, identifying quantifiable sensory abnormalities in various somatosensory submodalities that can be used as diagnostic tests.