Cognitive flexibility in autistic children: A comparison between high functioning and low functioning children using DCCS

A key feature of Autism Spectrum Disorders (ASD) is the presence of restricted, repetitive, and stereotyped behavior. often manifested with inflexible routines and restricted set of interests and activities. The findings about inflexibility in people with ASD suggests a number of reflections about the different deficits underlying ASD. For example people with ASD show a deficit in attentional shifting but not in focused attention or sustained attention (May, Rinehart, Wilding & Cornish, 2013; Sanders, Johnson, Garavan, Gill, & Gallagher, 2008; Johnson, Robertson, Kelly, Silk, Barry, & Daibhis, 2007; Landry & Bryson, 2004). Behavioral inflexibility has often been explored with card sorting task. Results with Wisconsin Card Sorting Task (WCST) show that children with High Functioning Autism (HFA) perform as typical development (TD) comparison group, but committ more perseverative errors (Reed, Watts & Truzoli, 2013; Van Eylen, Boets, Steyaert, Evers, Wagemans & Noens, 2011; Robinson, Goddard, Dritschel & Howlin, 2009). Fewer studies have explored the performance of children with Low Functiong Autism (LFA) in this type of tasks. A study by Reed, Watts e Truzoli (2013) using a non-verbal card sorting task, show that LFA were able to a learn a first sorting rule, but they couldn't switch to a different rule and made significantly more errors than the comparison group. Research question and hypotheses The aim of this research is to explore mental flexibility in children with HFA and LFA and to compare their performance, to show similarities and differences. In a second time we would compare the performance of ASD with a TD group. Method The LFA group is composed by 21 children (17 boys, 4 girls, ma=10.2, IQ=67), the HFA group is composed by 31 children (28 boys, 3 girls, ma=9.6, IQ=93), the TD group is composed by 23 children (19 boys, 4 girls, ma=9.1, IQ=110). The Dimensional Change Card Sort (Zelazo et al., 2002), was used to assess cognitive flexibility. Results Our results show that all the children are able to pass the first phase (sort by colour). On the contrary, the 62% of children with LFA (13/21) manage to pass the second phase (sort by shape) while the 80% of HFA (26/31) and all the TD children are able to pass it. Regarding the third switching phase that requires to keep in mind two different rules, none of the LFA and only 21% of HFA group (8/31) pass this phase and most of TD are able to keep in mind both the rules at the same time (83%, 19/23). Regarding the number of cards correctly sorted, children with LFA classify significantly less cards than HFA (z=-2.933; p<.01) and then TD (z=-4.997; p<.001). The HFA children, in turn, are significantly less accurate than TD (z=-3.572; p<.001). Discussion Consistently with previous researches, our results confirm the impairment of ASDs in mental flexibility task. Moreover, this deficit varies across the spectrum, with LFA group that shows the greater impairment.