Neural correlates of taste reactivity in autism spectrum disorder

Alex Martin,Cameron D Riddell,W Kyle Simmons,Jason A Avery,Sophie Wohltjen,Lauren Kenworthy,John E Ingeholm,Gregory L Wallace,Meghan Collins,Stephen J Gotts

doi:10.1016/j.nicl.2018.04.008

Abstract

Selective or ‘picky’ eating habits are common among those with autism spectrum disorder (ASD). These behaviors are often related to aberrant sensory experience in individuals with ASD, including heightened reactivity to food taste and texture. However, very little is known about the neural mechanisms that underlie taste reactivity in ASD. In the present study, food-related neural responses were evaluated in 21 young adult and adolescent males diagnosed with ASD without intellectual disability, and 21 typically-developing (TD) controls. Taste reactivity was assessed using the Adolescent/Adult Sensory Profile, a clinical self-report measure. Functional magnetic resonance imaging was used to evaluate hemodynamic responses to sweet (vs. neutral) tastants and food pictures. Subjects also underwent resting-state functional connectivity scans.The ASD and TD individuals did not differ in their hemodynamic response to gustatory stimuli. However, the ASD subjects, but not the controls, exhibited a positive association between self-reported taste reactivity and the response to sweet tastants within the insular cortex and multiple brain regions associated with gustatory perception and reward. There was a strong interaction between diagnostic group and taste reactivity on tastant response in brain regions associated with ASD pathophysiology, including the bilateral anterior superior temporal sulcus (STS). This interaction of diagnosis and taste reactivity was also observed in the resting state functional connectivity between the anterior STS and dorsal mid-insula (i.e., gustatory cortex).These results suggest that self-reported heightened taste reactivity in ASD is associated with heightened brain responses to food-related stimuli and atypical functional connectivity of primary gustatory cortex, which may predispose these individuals to maladaptive and unhealthy patterns of selective eating behavior.Trial registration(clinicaltrials.gov identifier) NCT01031407. Registered: December 14, 2009.

Highlights

Selective or ‘picky’ eating habits are a common feature of autism spectrum disorder (ASD) (Cermak et al, 2010; Diolordi et al, 2014; Kuschner et al, 2015; Williams et al, 2000)
This relationship between taste reactivity and diet was significant in the ASD group on its own (r(18) = −0.42; p < 0.04), though groups did not differ in this relationship (p = 0.88)
Groups did not differ in the molarity of their preferred sweet tastant (p = 0.80) during the pre-scan taste assessment or in the tastant they received during scanning (p = 0.78)

Summary

Introduction

Selective or ‘picky’ eating habits are a common feature of autism spectrum disorder (ASD) (Cermak et al, 2010; Diolordi et al, 2014; Kuschner et al, 2015; Williams et al, 2000). In many individuals with ASD, these atypical eating behaviors never fully resolve (Fodstad and Matson, 2008) This high degree of selective eating can lead to the development of poor diets in children with ASD (Sharp et al, 2013), which in turn can lead to inadequate or improper nutrition and poor health outcomes such as a higher risk for obesity (Phillips et al, 2014). These atypical eating behaviors constitute an added burden on families and caregivers, often leading to significant stress at mealtimes (Anderson et al, 2012)

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