A Two-Hit Model of Autism

Picci, Giorgia; Scherf, K. Suzanne

doi:10.1177/2167702614540646

Cited by 165 publications

(76 citation statements)

References 184 publications

(250 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This is in contrast to much more limited and circumscribed group differences in the children/young adolescent and adult age bands. This change in trajectory during adolescence is broadly consistent with structural neuroimaging findings of early overgrowth phase followed by later volumetric decline (42–43), and may reflect the compound effects of pubertal reorganization in an already developmentally compromised brain as described by Picci and Scherf in their “two-hit” model of autism (51). …”

Section: Discussionsupporting

confidence: 82%

Thalamocortical Dysconnectivity in Autism Spectrum Disorder: An Analysis of the Autism Brain Imaging Data Exchange

Woodward

Giraldo‐Chica

Rogers

et al. 2017

Biological Psychiatry: Cognitive Neuroscience and Neuroimaging

102

109

View full text Add to dashboard Cite

Background Individuals with autism spectrum disorder (ASD) exhibit differences in basic sensorimotor processing as well as general cortical excitability. These observations converge to implicate thalamocortical connectivity as a potential unifying neural mechanism. The goal of this study was to clarify mixed findings on thalamocortical functional connectivity in a large sample of individuals with ASD. Methods Using the Autism Brain Imaging Data Exchange (ABIDE), we examined thalamocortical functional connectivity in 228 individuals with ASD and a matched comparison group of 228 typically developing individuals. In order to fully characterize thalamocortical functional networks, we employed complementary seed-based approaches that examined connectivity of major cortical divisions (e.g. prefrontal cortex, temporal lobe) with the thalamus and whole-brain connectivity of specific thalamic sub-regions. Results Prefrontal cortex, temporal lobe, and sensorimotor cortex exhibited hyper-connectivity with the thalamus in ASD. In the whole-brain analysis, hyper-connectivity of several thalamic seeds included multiple cortical areas, but tended to converge in temporal cortical areas, including the temporoparietal junction. Follow-up analyses of age effects revealed that the connectivity abnormalities in ASD were more pronounced in adolescents compared to children and adults. Conclusions These results confirm previous findings of temporal and motor thalamocortical hyper-connectivity in ASD, and extend them to include somatosensory and prefrontal cortex. While not directly addressable with the data available in ABIDE, this widespread hyper-connectivity could theoretically account for sensorimotor symptoms and general cortical excitability in ASD. Future studies should target comprehensive clinical and behavioral characterization in combination with functional connectivity in order to explore this possibility.

show abstract

Section: Discussionsupporting

confidence: 82%

Thalamocortical Dysconnectivity in Autism Spectrum Disorder: An Analysis of the Autism Brain Imaging Data Exchange

Woodward

Giraldo‐Chica

Rogers

et al. 2017

Biological Psychiatry: Cognitive Neuroscience and Neuroimaging

102

109

View full text Add to dashboard Cite

show abstract

“…Typical development of insight into social relationships involves not only an understanding of others’ mental states but also an understanding and interest in one’s own role in a relationship, an interest which increases during adolescence (Picci & Scherf 2015). The current findings suggest that adolescents with ASD may be less sensitive to relative social information that may contribute to impaired vicarious effort-based decision-making.…”

Section: Discussionmentioning

confidence: 99%

Vicarious Effort-Based Decision-Making in Autism Spectrum Disorders

Mosner

Kinard

McWeeny

et al. 2017

J Autism Dev Disord

View full text Add to dashboard Cite

This study investigated vicarious effort-based decision-making in 50 adolescents with autism spectrum disorders (ASD) compared to 32 controls using the Effort Expenditure for Rewards Task. Participants made choices to win money for themselves or for another person. When choosing for themselves, the ASD group exhibited relatively similar patterns of effort-based decision-making across reward parameters. However, when choosing for another person, the ASD group demonstrated relatively decreased sensitivity to reward magnitude, particularly in the high magnitude condition. Finally, patterns of responding in the ASD group were related to individual differences in consummatory pleasure capacity. These findings indicate atypical vicarious effort-based decision-making in ASD and more broadly add to the growing body of literature addressing social reward processing deficits in ASD.

show abstract

“…There are a number of potential explanations for slowing of language trajectories into adulthood. There is some evidence of a 'second wave of deficit' or 'second hit' that emerges in the second decade of life that may impact trajectories of development (Minshew & Williams, 2007;Picci & Scherf, 2015). It has been estimated that 30% of children with ASD experience deterioration in functioning over several years following puberty onset.…”

Section: Summary Of Findings From Studiesmentioning

confidence: 99%

“…It has been estimated that 30% of children with ASD experience deterioration in functioning over several years following puberty onset. It has been hypothesised that the combination of co-occurring increase in adolescent-specific developmental tasks, increasing complexity of language and social communication required during adolescence, combined with pubertal hormone surges may contribute to this divergence or slowing of developmental trajectories (Picci & Scherf, 2015).…”

Section: Summary Of Findings From Studiesmentioning

confidence: 99%

A systematic review and meta-analysis of the prognosis of language outcomes for individuals with autism spectrum disorder

Brignell

Morgan

Woolfenden

et al. 2018

Autism & Developmental Language Impairments

View full text Add to dashboard Cite

Background: Language difficulties are common in autism spectrum disorder, yet little is known about the prognosis of language in children with autism spectrum disorder. The aim of this study was to systematically review studies reporting language outcomes in individuals with autism spectrum disorder. Method: A comprehensive search strategy with a well-established sensitive prognosis filter for Medline, adapted for five other databases, was used. Included studies observed individuals diagnosed with autism spectrum disorder for !12 months and had !30 participants. Risk of bias was assessed. Results: Fifty-four studies (N ¼ 5064) met inclusion criteria. Language outcomes were standardised assessments (n ¼ 35), notation of presence/absence of verbal language (n ¼ 11) or both (n ¼ 8). Age at baseline ranged from 17 months to 26 years, duration of follow-up from 1 to 38 years. Most publications (92%) were rated medium to high risk of bias. In all but one study individuals had below-average scores at baseline and follow-up. However, in most (n ¼ 24/25; 96%) studies reporting standard scores, individuals (aged 11 years at follow-up) progressed at a comparable rate to age-expected norms or demonstrated some 'catch up' over time. Meta-analyses found mean standard scores increased over time in three language domains (composite receptive language, composite expressive language and adaptive language). Nineteen to thirty percent of children aged five years and under gained verbal language. For children aged over five years 5-32% gained verbal language over the course of study. Age, baseline language scores, IQ and length of followup did not moderate between study differences in composite language or adaptive language growth or the acquisition of verbal language. Conclusion: Despite variability in study methods, findings were consistent, with the majority of studies reporting children under 11 years on average progressed at a comparable rate to age-expected norms or with some 'catchup' over time. Implications: This review provides synthesised information for families and clinicians on language development over time and on language outcomes for individuals with autism spectrum disorder. Such information can be useful for prognostic counselling and may assist planning around future resources and support needs. This review also makes recommendations regarding methodology for future studies so that prognosis can become more fine-tuned at an individual level.

show abstract

A Two-Hit Model of Autism

Cited by 165 publications

References 184 publications

Thalamocortical Dysconnectivity in Autism Spectrum Disorder: An Analysis of the Autism Brain Imaging Data Exchange

Thalamocortical Dysconnectivity in Autism Spectrum Disorder: An Analysis of the Autism Brain Imaging Data Exchange

Vicarious Effort-Based Decision-Making in Autism Spectrum Disorders

A systematic review and meta-analysis of the prognosis of language outcomes for individuals with autism spectrum disorder

Contact Info

Product

Resources

About