TRIGGER-SPECIFIC OUTCOMES OF FUNCTIONAL COMMUNICATION TRAINING: ADDRESSING SENSORY HYPERSENSITIVITY AND MALADAPTIVE BEHAVIORS IN AUTISM SPECTRUM DISORDER

Abstract

This single-case experimental study examined how Functional Communication Training (FCT) reduces self-injurious behaviors (SIBs) and self-stimulatory behaviors (SSBs) in a 9-year-old boy with Autism Spectrum Disorder and mild intellectual disability by targeting fast (n = 25) and slow (n = 22) sensory triggers identified through Functional Behavior Assessment across seven hypersensitivity domains. Using an ABAB design and a three-month home-based FCT program, caregivers implemented extinction, reinforcement, PECS-based and single-word Functional Communication Responses (FCRs). Baseline data showed the highest SIB/SSB frequencies in visual (14/min) and tactile (13/min) domains at mild–moderate intensity. After FCT, fast-trigger behaviors reduced by 25.8% versus 20.7% for slow triggers, with SSBs decreasing more than SIBs (38.1% vs. 27.5%). Effect-size indices (Tau-U, NAP, PND) demonstrated clear treatment effects, reversal upon withdrawal, and replication in reintroduction, confirming experimental control. FCRs (picture exchange and one-word vocalizations) increased progressively across phases. The intervention showed the strongest impact on rapid sensory antecedents, while slow triggers required longer shaping. Findings highlight FCT as a culturally adaptable, trigger-specific intervention capable of reducing sensory-maintained maladaptive behaviors and improving communication outcomes in South Asian home contexts, despite single-case limitations.