Ch15 - Module 3

Autism Spectrum Disorder

What is autism?

characterized by:

• differences in social interactions

• communication

• the presence of repetitive, stereotyped behaviours

• fixated interests

• strict adherence to routines

What is the word autism derived from?

*auto* “self”, *-ism* “condition”

What is a syndrome related to autism but only present in girls?

Rett Syndrome

What are the social symptoms of autism?

Social Symptoms

1. infants are ambivalent about being held

2. arched backs when picked up

3. may not look or smile

4. seek someone else for comfort

5. limited social relationships

6. avoid or reduce eye contact

What are the language symptoms of autism?

Language Symptoms

1. language may be altered, delayed, or nonexistent

2. could include echoing or self-reference in the third person

3. memorize and repeats words or phrases

4. talking without understanding others’ interests or misinterpreting their literal speech

What are the self-interest symptoms of autism?

Interests

1. particular interests & behaviours

2. stereotyped movements (flapping hands, rocking)

3. investigates objects (sniffing, textiles, motion)

4. extreme attachment to an object

5. precise routines (distress when not followed)

What is the concordance rate for ASD?

70-90% (monozygotic twins)

5-10% (dizygotic twins)

19% likelihood with one older sibling

32% chance with multiple older siblings

What are the causes of autism?

1. Rubella during pregnancy

2. Prenatal Thalidomide

3. Encephalitis from herepes

4. Tuberous Sclerosis

What brain changes are caused by autism?

1. 10% increase in brain size
2. 1-2% increase in adolescence
3. Rapid growth f frontal and temporal cortexes only in the first 2 years of life
4. Striate and Extrastriate cortexes remain unchanged
5. Amygdala grows unusually and contains fewer neurons in adulthood
6. The volume of white matter containing short-range axons increased
7. The volume of white matter containing long-range axons did not increase
8. Increased volume of the caudate nucleus
9. Altered development of mirror neuron system
10. Changes in steroid hormones and neuropeptide signalling

What is the theory of mind?

The ability to predict and explain the behaviour of other humans via their mental states