UC Davis

Differences in sensory processing are a recognized trait of many individuals with autism spectrum disorder (ASD; American Psychiatric Association, 2013; Tomchek & Dunn, 2007) and is also common in children with attention-deficit/hyperactivity disorder (ADHD; Dunn & Bennett, 2002; Ghanizadeh, 2011). Difficulty with processing complex sensory environments can make activities of daily living more difficult for the individual (Baker et al., 2008; Jasmin et al., 2009). For school-aged children, attending school is an important activity of daily living and several studies indicate that sensory processing may impact attention (Dellapiazza et al., 2018; Liss et al., 2006; Moore et al., 2010) and behavior (Baker et al., 2008; Lane et al., 2010; O’Donnell et al., 2012) in ways that interfere with children’s ability to learn. Yet, the relationship between sensory processing and academic achievement has rarely been studied in autistic or ADHD children. Those few studies that have been conducted indicate that difficulty with sensory processing is linked to teacher reports of low academic achievement in children with both conditions as measured (Ashburner et al., 2008; Butera et al., 2020; Davis et al., 2009). This dissertation seeks to further understand sensory processing in autistic and ADHD children and its possible impact on attention, behavior, and academic achievement by: 1) examining the relationships between sensory processing modalities, attention, and objective measures of academic achievement in autistic, ADHD, and neurotypical children, rather than teacher reports; and 2) examining the potential mediating role of behavior in the relations between sensory processing patterns and academic achievement in a sample of autistic children. In Paper 1, autistic and ADHD children demonstrated similar levels of atypical sensory processing, but overall there was inconsistent evidence of the impact of sensory processing on attention and academic achievement. In Paper 2, sensory processing patterns were consistently related to parent reported behaviors such as anxiety, withdrawal, and attention, but these behaviors were not related to academic achievement. Together, these studies provide little evidence to support the hypothesis that sensory processing is related to objective measures of academic achievement in autistic, ADHD, or neurotypical students. However, further research is needed to understand how sensory processing may impact other aspects of emotion, cognition, and behavior that may impact school attendance and learning, such as happiness, ability to interact with others and participate in the routine activities of the school day. Research also needs to go beyond parent report of sensory processing to include objective classroom measures and self-report measures, which may be more sensitive to the differences in sensory processing (Williams et al., 2018) that are related to classroom learning.