1. Autism A spectrum of neuropsychiatric disorders characterized by
deficits in social interaction and communication, and unusual
and repetitive behavior.

2. Autism is a Pervasive Developmental Disorder (PDD)
Who, what, when where why?
The human brain-normal and abnormal development
Genetics
Language and cognition
Social implications
Interventions and therapies

3. What is a developmental disorder/disability?
Birth defects
Developmental Disabilities
-Spina bifida
-Heart defects
-Cleft palate/club foot
-Tay Sachs disease
-Cerebral palsy
-Down’s syndrome
-Learning disabilities and ADHD
-Autism and PDDs
Pervasive developmental disorders
a group of disorders that are characterized by : impairments in social
interaction, impairment in verbal and nonverbal communication, and a restrictive,
stereotypic pattern of behaviours
Autism
Asperger’s
Rett’s Syndrome
Childhood disintegrative disorder
PDD-NOS

4. Characteristics of Autism (1)

5. Characteristics of Autism (2)

10. A little history…

11. A little history…

12. Epidemiology of autism

13. Epidemiology of autism

14. Neuropathology

15. Figure 1. Orthogonal views for segmenting the amygdala and hippocampus on MRI sections
Schumann, C. M. et al. J. Neurosci. 2004;24:
Copyright ©2004 Society for Neuroscience

16. Figure 5. Absolute left (a) and right (b) hippocampal volume (in cubic centimeters) by diagnostic group for subjects years of age (*p
Schumann, C. M. et al. J. Neurosci. 2004;24:
Copyright ©2004 Society for Neuroscience

17. Neuropathology
What developmental processes might lead to a larger brain?
-Increased neurogenesis
-Increased gliogenesis, myelination
-Increased synaptogenesis
-Disturbed migration
-Decreased apoptosis
-Decreased dendritic pruning

18. Cellular pathology

19. Other brain regions

20. Neuropathology summary

21. Neurotransmitters
Alterations in many neurotransmitter systems in autism
-Glutamate
-GABA
-Serotonin
-Catecholamines (norepinephrine, dopamine)
-Neuropeptides

22. Changes in glutamate and/or GABA could lead to
alterations in excitation/inhibition

23. Serotonin

24. Serotonin- Developmental changes
Cortical decreases of AMT uptake (red areas) I
n three autistic children in (1B) the frontal cortex
(left hemisphere), (1C) frontal and temporal cortices
(left hemisphere), and (1D) frontal, parietal and
temporal cortices (right hemisphere) are shown.

25. Is autism a genetic disorder?

26. Is autism a genetic disorder?

27. First autism twin study-1977
Folstein and Rutter, Nature 1977
- Total 25 autistic individuals
-4/11 MZ pairs concordant for autism (36%)
-0/10 DZ pairs were autistic (0%)

28. Twin studies - Is autism a spectrum?
Do non-autistic MZ twins show other abnormalities?

29. Further twin studies
Steffenburg 1989, Bailey 1995

30. Conclusions from twin studies

31. Family studies also suggest genetic link

32. Family studies-negative results

33. Looking for autism genes

34. Chromosomal abnormalities

35. Genes identified from linkage analysis

36. Genes identified from linkage analysis

37. Genes identified from linkage analysis

38. Gene summary

39. Controversies in autism