111 Imaging studies have shown that frontal parietal and striatal circuitry are

111 imaging studies have shown that frontal parietal

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111 Imaging studies have shown that frontal, parietal, and striatal circuitry are the main systems implicated in executive dysfunction in autism. 107,108 Executive dysfunction is not specific to autism; it is commonly reported in other neuropsychiatric conditions (although with different patterns). One view is that strong executive function early in life could protect at-risk individuals from autism or other neurodevelop- mental conditions by compensating for deficits in other brain systems. 112 Individuals with autism often have a preference for, and superiority in, processing of local rather than global sensory-perceptual features (table 4). Individuals without autism often show the opposite profile. This difference could explain the excellent attention to detail, enhanced sensory-perceptual processing and discrimination, and idiosyncratic sensory responsivity (ie, hyper-reactivity or hyporeactivity to sensory input or unusual interest in sensory features of the environment) in autism. It could also contribute to the exceptional abilities disproportion- ately recorded in individuals with autism. 113,114 Addition- ally, top-down information processing in individuals with autism is often characterised by reduced recognition of the global context, 115 and a strong preference to derive rule-based systems. 113 The neural bases are spatially distributed and task dependent, but converge on enhanced recruitment of primary sensory cortices, reduced recruitment of association and frontal cortices involved in top-down control, 116 and enhanced synchro- nisation of parietal-occipital circuits. 117 Neurobiology Neurobiological investigation has identified patterns of brain perfusion and neural biochemical characteristics, which are described elsewhere. 118,119 Additionally, systems- level connectivity features and plausible neuroanatomi- cal, cellular, and molecular underpinnings of autism have been identified. Evidence from electrophysiology and functional neuroimaging (resting-state and task-based connectivity), 120 structural neuroimaging (white-matter Main behavioural features Main cognitive (psychological) constructs Social cognition and social perception Atypical social interaction and social communication Gaze and eye contact; emotion perception; face processing; biological motion perception; social attention and orienting; social motivation; social reward processing; non-verbal communication; imitation; affective empathy and sympathy; joint attention; pretend play; theory of mind or mental perspective taking; self-referential cognition; alexithymia (diffi culty understanding and describing own emotions); metacognitive awareness Executive function Repetitive and stereotyped behaviour; atypical social interaction and social communication Cognitive flexibility; planning; inhibitory control; attention shifting; monitoring; generativity; working memory Bottom-up and top-down (local vs global) information processing* Idiosyncratic sensory-perceptual processing; excellent attention to detail; restricted interests and repetitive
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