Investigation of the Effect of Snoezelen-Based Occupational Therapy Intervention on Sleep and Behavioral Problems in 18-36 Months Children at Risk of Autism

Introduction Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by social interaction, social communication, and repetitive behavioral problems associated with sensory processing problems (SPP) that occur before the age of 3, according to The Diagnostic and Statistical Manual of Mental Disorders classification system (DSM-5). Early symptoms of ASD are characterized by limited social participation, inadequate performance in gestures, inability to initiate or maintain interactions with others, and repetitive movements. These symptoms are used as criteria for the diagnosis of ASD. However, in addition to the symptoms used as criteria, parents reported that they observed behavioral problems such as tantrums, senseless fear, and sleep problems in their children at risk for ASD more than in children with typical development. These additional symptoms observed by parents are also used as diagnostic criteria. Moreover, after eating problems, sleep problems, and SPP, tantrums and challenging behaviors are the most difficult for parents.

Sleep problems are 40% to 80% more common in ASD than in typically developing children. In children with typical development, this rate is between 25% and 40%. Sleep problems seen in ASD can be categorized under various headings. These include delayed falling asleep, sleep refusal, decreased sleep time, frequent awakenings, and bedtime resistance. The reason for the high prevalence of sleep problems in ASD is still unclear. Biological, genetic, intrinsic-motivational, behavioral, and sensory problems are thought to play a role.

The studies show that behavioral symptoms can cause sleep problems and that insufficient sleep triggers core behavioral ASD symptoms such as tantrums, aggression, and social communication difficulties. It is reported that sleep and behavioral problems are mutually triggering factors in ASD. In more detail, SPP may also cause sleep and behavior problems due to intrinsic-behavioral problems.

SPP is observed in more than 90% of children with ASD. According to DSM-5, SPP includes hyper- or hypo-reactive responses to sensory stimuli. Inappropriate responses to stimuli from the environment and the body cause behavioral problems. Sensory sensitivity causes problems in maintaining and sustaining calm and appropriate behavior toward the environment. Studies focusing on the relationship between ASD and sleep suggest that children with ASD who have problems with sensory reactivity, sensory seeking, and filtering incoming stimuli may have sleep disorders. In other words, behavioral problems caused by certain sensory stimuli can be seen as self-harm, aggression, and sleep problems. Sensory integration interventions in SPP aim to provide the infant with controlled and meaningful sensory experiences and accurate environmental responses. Sensory processing interventions are based on models such as sensory integration and snoezelen-based programs that incorporate neuroplasticity and engagement. Studies suggest deep pressure, vestibular, and tactile stimuli will help release endorphins and serotonin and increase perceived sleep quality and calmness in sensory-based sleep disorders.

Snoezelen-based interventions, in which sensory stimuli are experienced in intense and multiple ways, are generally used to reduce stress and depression and provide a sense of relaxation. Snoezelen-based interventions are used to relax individuals in various diagnostic groups, such as dementia and mental retardation, and to reduce agitation, depression, and aggression levels. In studies on ASD children, snoezelen-based interventions have improved social skills and decreased self-harm behaviors. It is stated that it positively affects sleep quality regarding its impact on sleep problems, but the evidence is insufficient.