LEC 12: Autism

What is Autism Spectrum Disorder?

A neurological and developmental disorder that begins early in childhood and lasts throughout a person's life, characterized by a range of symptoms that affect communication, social interaction, and behaviour/interests

Prevalence of ASD

• 1 in 66, 78% diagnosed by age 8

• male to female ratio is 4:1

Etiology of ASD

• ASD is highly heritable

• Genetic predisposition combined with an environmental impact

  • exposure to air pollutants

  • poor socioeconomic status

Risk factors of developing ASD

• maternal diet: deficient in essential nutrients; affects gut microbiome and immune responses

• folic acid status

• maternal smoking, alcohol or drugs during pregnancy

• maternal infection during pregnancy

• advanced maternal and paternal age

Theory of Mind and how to test for it

• the ability to attribute mental states to others, knowing that others are separate selves, with own points of view and feelings

• the Sally-Anne test

Neurobiology of autism

• ASD results from overall brain reorganization that begins early in development:

  • accelerated brain development early in life (“early brain overgrowth”)

  • morphological abnormalities at the microstructural level

Treatment for ASD

• no pharmacotherapy available

• Applied Behaviour Analysis (ABA): emphasize play, social interaction and communication initiation; the “natural consequences” are the reward (controversial)

The Gut-Brain Axis

the gut microbiome can influence brain function, potentially affecting behaviours associated with autism

Mirror neuron system

• provides a neurobiological basis for social cognition

• mirror neurons respond to the understanding of an action, not to some superficial aspect of it

• these neurons are found all throughout the cortex

• they also play a role in empathy