Neural mechanisms of naturalistic viewing in children with autism or ADHD
Human Cognitive and Systems Neuroscience
Personality Psychology, Clinical and Medical Psychology, Methodology
Final Report Abstract
The correct perception of human communication signals, such as from the voice, is fundamental for successful social communication. There is evidence that impairments in auditory sensory processing might contribute significantly to difficulties in auditory social cognition in autism. Autism spectrum disorder (ASD) is a neurodevelopmental condition associated with impaired social interaction and communication. Previous functional magnetic resonance imaging (fMRI) studies showed that impaired voice perception in ASD is associated with reduced cortical and subcortical responses in brain regions associated with voice acoustic processing. However, these previous studies included only adults with or without ASD. The generalisability to younger ages and the specificity of these findings is unclear. In our project, we aimed to test whether (i) similar dysfunctional brain responses can be observed also in children with autism and (ii) whether these dysfunctional mechanisms are specific to ASD or also occur in another neurodevelopmental condition, that has been associated with altered sensory auditory processing (Jafari et al., 2015) and reduced social cognition skills, i.e. attention deficit hyperactivity disorder (ADHD; APA, 2013). To answer these open research questions we analysed open resource data from children with ASD (n = 51), ADHD (n = 153), and typically developing children (n = 136) (aged between 5 and 17 years old) from two fMRI experiments: (i) a resting state experiment in which brain responses are recorded at rest (rest condition) and (ii) a naturalistic listening experiment, during which children freely watch the same audio-visual movie (naturalistic listening condition). Systematic analyses of the final data are ongoing. First results show that in typically developing children there is enhanced connectivity between the voice-sensitive right posterior superior temporal sulcus (pSTS/G) and IC when exposed to auditory social signals (i.e., naturalistic listening condition) as compared to the rest condition. However, there was no such enhanced connectivity within the ASD group. As compared to the ASD group, the ADHD group showed even lower connectivity between voice-sensitive pSTS/G and IC when exposed to naturalistic auditory stimuli as compared to the rest condition. Additionally, the strength of connectivity between voice-sensitive pSTS/G and IC correlated positively with a measure of speech ability for typically developing children only. These first results indicate that a stronger connectivity between voice-sensitive cortical and subcortical auditory sensory pathway structures can be observed in typically developing children and that the strength of this connectivity is associated with verbal skills. Our findings further indicate that in ASD, connectivity patterns between these cortical and subcortical auditory sensory structures are altered when processing naturalistic auditory signals. This result complements previous findings which indicate that the processing of voices is impaired on the cortical as well as on the subcortical level in ASD. Altered connectivity patterns can also be observed in ADHD, a condition with partially common etiology with ASD. The nature of this altered connectivity in ADHD will be further investigated in an additional collaborative study. Investigating sensory auditory processing in ASD and related neurodevelopmental disorders is important, because it provides information about the underlying basic mechanisms, which might at least partly underlie impaired social communication. The transdiagnostic approach (i.e., comparing different clinical conditions within the same study) holds the potential to further improve the differentiation and treatment of forms of psychopathology, an often challenging task in clinical practice.
