a summary of a published research article
Sensory Features and Repetitive Behaviors in Children with Autism and Developmental Delays
By B. A. Boyd, G. T. Baranek, J. Sideris, M. D. Poe, L. R. Watson, E. Patten, and H. Miller
The University of North Carolina at Chapel Hill
Sensory symptoms are considered secondary features of autism because although they are present in many individuals with autism, they are not universally experienced. However, children experience and explore their worlds through sensory input and impairments in this area can affect children’s ability to relate to other people.
Repetitive behaviors are defined by their repetition, inappropriateness, similarity across contexts, and an overarching behavioral rigidity (Boyd et al, 2009). These behaviors are presumed to provide internal sensory stimulation to individuals with autism.
This research study aimed to examine the relationship between atypical sensory features and restricted, repetitive behaviors. The authors used parent reports and observational measures of 67 children with autism and 42 children with developmental delays.
The three sensory features considered in this study were: hyperresponsiveness, hyporesponsiveness, and sensory seeking.
Hyperresponsiveness is behavioral over-reactivity to sensory stimuli. Contrastingly, hyporesponsiveness is behavioral under-reactivity to sensory stimuli. Sensory seeking involves fascination with or craving for certain stimuli. Baranek et al (2006) found the hyperresponsive sensory pattern to be similar in individuals with autism and developmental delays. On the other hand, hyporesponsiveness discriminated the autism group from both the developmental delay and typical comparison groups.
Previous studies only used parent report measures, so Boyd et al also used observational methods, in order to further understand these behaviors.
The results showed that high levels of hyperresponsive behaviors predicted high levels of repetitive behaviors. The authors did not find significant associations between hypo-responsiveness or sensory seeking and repetitive behaviors, with the exception that sensory seeking was associated with ritualistic behaviors.
Additionally, the authors found an association between hyperresponsiveness and ritualistic behaviors, and research has found that anxiety plays a significant role in the expression of these compulsive behaviors. Hyperawareness of sensory stimuli in the environment can lead to feelings of anxiety, followed by compulsive or ritualistic behavior to alleviate the anxiety.
Sensory seeking was only significantly associated with ritualistic/sameness behaviors. This may indicate that there is a different pathogenesis associated with children who display hyperresponsiveness and ritualistic behaviors versus those who seek out certain stimuli in their environment but also display ritualistic/sameness behaviors.
These findings suggest that similar neurobiological mechanisms may contribute to hyperresponsive sensory symptoms and repetitive behaviors and have implications for diagnostic classification.
Brian Boyd., PhD, is an Assistant Professor in the Division of Occupational Science at the University of North Carolina, School of Medicine.
This research was supported by a grant from NICHD (R01 HD42168). We thank the families whose participation made this study possible.
For more information about The Sensory Experiences Project please visit our website: http://www.med.unc.edu/sep
This Research Brief was based on the following article: Boyd,B. A., Baranek, G. T., Sideris, J., Poe, M. D, Watson, L. R., Patten, E. & Miller, H. (2010). Sensory features and repetitive behaviors in children with autism and developmental delays. Autism Research, 3, 78-87.