Optimizing a Mock Scanner Protocol to Establish Motion Control of the MRI Environment in Individuals with Autism and Intellectual Disability

Abstract

Behavioural procedures can be effective and safe methods for establishing motion control during magnetic resonance imaging (MRI) scans. However, very few protocols that are practical and can be amendable to individuals with autism spectrum disorder (ASD) and intellectual disability (ID) currently exist. For this reason, we modified and tested the protocol proposed by Cox et al. (2017) to address this limitation and optimize the time efficiency of motion control training. A multi-component intervention that included an eight-step stimulus fading procedure in combination with prompting and contingent reinforcement was used to establish compliance with a sequence of successive approximations to a mock MRI by individuals with a diagnosis of ASD some with comorbid ID. In this study, participants were exposed to a time-limited shaping procedure first (pre-test at step 9 of the stimulus fading procedure). Subsequently, participants that did not pass the shaping procedure were exposed to the eight-step stimulus fading procedure. If the participants were not able to complete the stimulus fading procedure successfully, additional treatment manipulations were implemented. Finally, participants who passed the procedure underwent a real MRI scan. A multiple baseline design across participants was used. Overall, 82% of the participants met the mastery criterion level in the mock MRI, and 68% of participants performed at the mastery criterion during the pre-test shaping sessions. The current approach produced time savings up to a factor of approximately 8.4 relative to Cox et al. In the real MRI, scan success was achieved with 74% of the participants. Methodological and procedural considerations, in addition to the limitations and future considerations of this work are discussed.