Visual and Hedonic Perception of Food Stimuli in Children with Autism Spectrum Disorders and their Relationship to Food Neophobia.

The present study examined whether children with autism spectrum disorder (ASD) and typically developing (TD) children differed in visual perception of food stimuli at both sensorimotor and affective levels. A potential link between visual perception and food neophobia was also investigated. To these aims, 11 children with ASD and 11 TD children were tested. Visual pictures of food were used, and food neophobia was assessed by the parents. Results revealed that children with ASD explored visually longer food stimuli than TD children. Complementary analyses revealed that whereas TD children explored more multiple-item dishes (vs. simple-item dishes), children with ASD explored all the dishes in a similar way. In addition, children with ASD gave more negative appreciation in general. Moreover, hedonic rating was negatively correlated with food neophobia scores in children with ASD, but not in TD children. In sum, we show here that children with ASD have more difficulty than TD children in liking a food when presented visually. Our findings also suggest that a prominent factor that needs to be considered is time management during the food choice process. They also provide new ways of measuring and understanding food neophobia in children with ASD.

Effects of familiarization on odor hedonic responses and food choices in children with autism spectrum disorders.

This study assessed whether olfactory familiarization can render food odors more pleasant, and consequently food more attractive, to children with autism spectrum disorder. Participants were first presented with a series of food odors (session 1). Then, they were familiarized on four occasions (time window: 5 weeks) with one of the two most neutral odors (the other neutral odor was used as control) (session 2). In session 3, participants smelled the entire series of odors again. Both verbal and facial responses were compared from session 1 to session 3. After session 3, the children were presented with two identical foods (one containing the familiarized odor and one the control odor) and were asked to choose between these foods. Results revealed (1) a specific increase in positive emotions for the familiarized odor and (2) that 68% of the children chose the food associated with the "familiarized odor" (children who chose the "familiarized odor" food exhibited significantly more sensory particularities). These findings suggest that it is possible to modulate olfactory emotions and expand the dietary repertoire of children with autism spectrum disorder. Application of this paradigm may enable innovative prospects for food education in autism.

Odor Perception in Children with Autism Spectrum Disorder and its Relationship to Food Neophobia.

Atypical sensory functioning in Autism Spectrum Disorder (ASD) has been well documented in the last decade for the visual, tactile and auditory systems, but olfaction in ASD is still understudied. The aim of the present study was to examine whether children with ASD and neuro-typically (NT) developed children differed in odor perception, at the cognitive (familiarity and identification ability), sensorimotor (olfactory exploration) and affective levels (hedonic evaluation). Because an important function of the sense of smell is its involvement in eating, from food selection to appreciation and recognition, a potential link between odor perception and food neophobia was also investigated. To these ends, 10 children between 6 and 13 years old diagnosed with ASD and 10 NT control children were tested. To compare performance, 16 stimuli were used and food neophobia was assessed by the parents on a short food neophobia scale. Results revealed that (i) significant hedonic discrimination between attractive and aversive odors was observed in NT (p = 0.005; d = 2.378) and ASD children (p = 0.042; d = 0.941), and (ii) hedonic discrimination level was negatively correlated with food neophobia scores in ASD (p = 0.007) but not NT children. In conclusion, this study offers new insights into odor perception in ASD children, highlighting a relationship between odor hedonic reactivity and eating behavior. This opens up new perspectives on both (i) the role of olfaction in the construction of eating behavior in ASD children, and (ii) the measurement and meaning of food neophobia in this population.