Exploring the Structure and Neurocognitive Correlates of Challenging Behaviour in Young People with Autism Spectrum Disorder

Background:  

Many young people with Autism Spectrum Disorder (ASD) exhibit ‘challenging behaviour’, characterised by severe non-compliance, aggression and self-injurious behaviour (SIB). The development of effective interventions requires greater knowledge of ASD-specific models of challenging behaviour. The collection of behaviours (non-compliance, aggression, SIB) subsumed under the term ‘challenging behaviour’ may be associated with different neurocognitive profiles.

Objectives:  

A detailed exploration of the neurocognitive profile associated with different aspects of challenging behaviour. Structural equation modelling will be used to explore the relationship between SIB and aggression, and their associated neurocognitive profiles.

Methods:  

This study involved 94 well-characterised adolescents (mean age 15.5 years) with a diagnosis of ASD from the Special Needs and Autism Project (SNAP), a longitudinal, population-based cohort. Parent-reported symptoms of SIB and aggressive behaviour were measured using items selected from the Profile of Neuropsychiatric Symptoms (PONS).  Assessment of the neurocognitive profile included performance on tasks of executive functioning (inhibition, flexibility, sustained and selective attention) and social cognition (emotion recognition, theory of mind). Clinician-rated ASD ICD-10 symptoms and IQ were included as co-variates.

Results:  

Initial analyses used bivariate regressions to explore relationships between aspects of challenging behaviour and neurocognitive task performance. FSIQ and then ASD symptoms were added as covariates to determine the specificity of the relationships. The final analyses will use SEM to build a comprehensive model.

Ratings of SIB and aggressive behaviour were explored in a varied sample of individuals with ASD (FSIQ: mean = 84.11 (17.46), range 50-119; clinician-rated ASD symptoms: mean = 8.04 (2.45), range 3-12). 

Mean SIB = .57 (1.12), range = 0-5, and mean aggressive behaviour = 5.36 (4.61), range = 0-17.5. SIB and aggressive behaviour were significantly correlated (r=0.44, p<0.01). SIB was associated with a greater number of ASD symptoms. No association was found with aggressive behaviour.

IQ: Aggressive behaviour was associated with lower FSIQ and performance but not verbal IQ. SIB was associated with a trend towards lower FS and verbal IQ.

Executive Functioning: Aggressive behaviour was associated with difficulties in flexibility, inhibition and sustained attention; however these did not remain after co-varying for IQ. SIB was not associated with any of these domains, but was associated with difficulties in selective attention. This became non-significant when co-varied for IQ.

Social Cognition: Aggressive behaviour was associated with specific difficulty in recognising fearful faces. This pattern of results remained when co-varied for both IQ and ASD symptoms. SIB was also associated with difficulties recognising fearful faces; however, this association became non-significant when co-varied for IQ. Neither aggressive behaviour nor SIB was associated with theory of mind ability.

Conclusions:  

Although a useful clinical term, explanatory models of challenging behaviour may need to consider SIB and aggressive behaviour separately. There appeared to be differential associations of the two domains with respect to IQ, executive functioning and emotion recognition. Better characterisation of the neurocognitive profile associated with each domain may inform development of future interventions, and be used to tailor interventions dependent on which aspect of challenging behaviour is more problematic for a given individual.