University Report: Autism and the Brain's Structural Changes

This report investigates the neurological changes associated with autism spectrum disorder (ASD). It begins with an introduction to autism, highlighting its characteristics of communication and social interaction difficulties, and repetitive behaviors, attributing it to genetic and environmental factors. The research question focuses on brain changes in autism, specifically the impact on synapses and information processing. The report then explores MRI evidence pointing to early brain overgrowth in ASDs, discussing local gyrification index (LGI) in the cerebral cortex, including the gyri and sulci. It references research findings that show increased LGI in children with autism, and variations in the thickness of the cerebral cortex. The report concludes by summarizing that autism symptoms appear during childhood and are influenced by several genetic factors, with changes in gyri and sulci playing an important role in autism development. The report is supported by references to relevant research papers.

Autism and the
brain
Name of the Student
Name of the University

Introduction
 Autism refers to a developmental disorder
 It is characterised by problems in communication and
social interaction and the affected people
demonstrate repetitive or restricted behaviour
 It can be accredited to a range of environmental and
genetic factors and several neuroanatomical changes
(Hahler and Elsabbagh 2015)
 Research question- What changes occur in the brain
during autism?

Impact on
synapse
 Autism generally creates an impact on information
processing in the human brain by modifying
organisation and connections of the synapses
between neurons
 Findings from a research suggests that abnormalities
in the enteric nervous system plays a major role in
the onset of autism (Rao and Gershon 2016)
 These abnormalities allow spread of disease
originated in intestine to the brain

MRI
evidences
 MRI evidences point towards early overgrowth of
brain in autism spectrum disorders (ASDs)
 Local gyrification of the brain in the left parietal, right
frontal and temporal regions have been linked to
autism
 Increase in gyrification represents early overgrowth of
the cortical regions of the brain among autistic
individuals (Kohli et al. 2018)
Figure 1- Gyrus and sulcus
Source- (Mcrae 2018)

LGI in
autism
 Gyrus and sulcus in the brain are not present in an
appropriate form in those diagnosed with autism
 Variations in thickness in the cerebral cortex, the
outer region of the brain have also been associated
with autism
 Children with ASD demonstrated remarkably
smooth fusiform gyrus, the region that helps in
recognition of faces, besides increase in local
gyrification index (LGI) (Mcrae 2018)

Gyrification
 Gyrification principally occurs for the duration of
prenatal and initial postnatal life.
 Increase in LGI in cingulate cortex, right dorsomedial
prefrontal cortex, left cingulate cortex, paracentral
cortex, and superior frontal gyrus have been found
among children aged 3-years, diagnosed with autism
(Libero et al. 2018)
 Greater surface area in left and right fusiform gyrus
and discrete shapes of cortical folding are observed
within diverse subgroups of ASD
Figure 2- Reduced LGI in boys with ASD
Source- (Libero et al. 2018)

Conclusion
 Autism symptoms appear first during childhood or
infancy and follow a steady progression without
diminution
 Several genetic factors predispose an individual to
autism
 Changes in the gyri and sulci play an important role in
autism development

References
Hahler, E.M. and Elsabbagh, M., 2015. Autism: A global
perspective. Current Developmental Disorders Reports, 2(1),
pp.58-64.
Kohli, J.S., Kinnear, M.K., Fong, C.H., Fishman, I., Carper, R.A.
and Müller, R.A., 2018. Local Cortical Gyrification is Increased
in Children With Autism Spectrum Disorders, but Decreases
Rapidly in Adolescents. Cerebral Cortex, 29(6), pp.2412-2423.
Libero, L.E., Schaer, M., Li, D.D., Amaral, D.G. and Nordahl,
C.W., 2018. A longitudinal study of local gyrification index in
young boys with autism spectrum disorder. Cerebral
Cortex, 29(6), pp.2575-2587.
Mcrae, M., 2018. Children With Autism Have Brains That Fold
Differently to Everybody Else's. [online] Available at:
https://www.sciencealert.com/differences-autism-brain-folding
-lateral-gyrification-index
[Accessed 22 Aug. 2019]
Rao, M. and Gershon, M.D., 2016. The bowel and beyond: the
enteric nervous system in neurological disorders. Nature
reviews Gastroenterology & hepatology, 13(9), p.517.

Thank
you!