Social Cognition and Autism

Neurogenesis

• Neuroplasticity:

  • Regional Level: The brain can change at a regional level.
  • Taxi Driver Study (Maguire et al., 2000): Demonstrated navigation-related structural changes in the hippocampi of taxi drivers.
    • Positive correlation between time as a taxi driver and posterior hippocampus volume.
    • Negative correlation between time as a taxi driver and anterior hippocampal volume.
  • Juggling Study (Draganski et al., 2004): Showed that learning new juggling skills leads to a transient increase in grey matter in the intraparietal sulcus, which reduces once practice stops.
  • Anatomical Plasticity:
    • Intense practice or extremes of behavior can produce visible structural changes (size, density).
    • These effects are generally small.
    • Synaptic plasticity is considered more important than large-scale structural changes in most of the general population.

• Neurogenesis:

  • Definition: The growth of new neurons.
  • Limited to a few regions in adults:
    • Subventricular zone: Neurons migrate to the olfactory bulb; can be redirected after brain injury.
    • Dentate gyrus of the Hippocampus: Produces approximately 700 neurons per day; rate decreases with age (Micheli et al., 2018).

• Neurogenic Hypothesis of Depression:

  • Evidence: Reduced hippocampal volume in depression.
  • Neurogenesis is reduced in depression.
  • Stress: A risk factor that inhibits neurogenesis.
  • Fluoxetine: Treats anxiety and depression and stimulates neurogenesis.
  • The process takes days to weeks to develop.
  • Neurogenesis in the dentate gyrus is considered more important than in the subventricular zone (Micheli et al. 2018, Lucassen et al. 2016).

• Major Depressive Disorder:

  • Prevalence: Affects 350 million people worldwide.
  • Symptoms: Include diminished ability to think or concentrate, indecisiveness, and cognitive impairments (executive function, attention, memory, processing speed, psychomotor skills) during both symptomatic and remitted phases.

• Exercise, Cognition, and Depression:

  • Short bursts of intense activity improve test performance.
  • Long-term improvements in cognition with exercise, especially in aging populations.
  • Exercise relieves symptoms of depression and may be more effective for mood symptoms than cognitive symptoms.
  • It is an effective treatment for depression related to stress and anxiety by affecting the HPA axis (Micheli et al., 2018).

Social Cognition

• Definition: Understanding what other people are thinking.

• Components:

  • Social Orienting:
    • Joint attention.
    • Considering another's intentions.
    • Responding appropriately.
    • Taking turns.
  • Language & Cognition:
    • Understanding idioms.
    • Symbolic play.
    • Non-verbal cues using executive function/planning/language.

• Theory of Mind:

  • Definition: The ability to attribute mental states to oneself and others, understanding that others have different beliefs, desires, intentions, and perspectives.
  • Also known as 'mind blindness' in the context of Autism (Simon Baron-Cohen, 1985).
  • Development: Normally develops around age 3-4; delayed in Autism.

• Theory of Mind Tests:

  • False Belief Tests like the Smarties Task.

• Brain Regions Involved:

  • Medial prefrontal cortex.
  • Temporal-parietal junction (TPJ).
  • Posterior superior temporal sulcus (pSTS).
  • Posterior cingulate cortex (PCC).
  • Precuneus (Medial Parietal Cortex).

• ChatGPT:

  • There are ongoing discussions around whether AI like ChatGPT possess a 'Theory of Mind' (Bubeck et al 2023).

Autism Spectrum Disorders

• Shift in Perspective: Viewing autism as a difference rather than a disability.
• Trends:
  • Significant increase in diagnoses in the last 10-15 years.
  • Varies by country.
  • 4:1 male to female ratio.
  • Some genetic component.
  • No approved drugs.
  • Spectrum disorder; neurodiversity.
• DSM-V Criteria:
  • Persistent deficits in social communication and social interaction across multiple contexts (must have all 3):
    • Deficits In social-emotional reciprocity.
    • Non-verbal communication issues.
    • Trouble developing, maintaining, and understanding relationships.
  • Two of the following:
    • Restricted, repetitive patterns of behavior, interests, or activities.
    • Insistence on sameness, inflexible adherence to routines.
    • Highly restricted, fixated interests that are abnormal in intensity or focus.
    • Hyper- or hyporeactivity to sensory input or unusual interest in sensory aspects of the environment.
• Common Behaviors:
  • Insistence on sameness.
  • Repetitive movements (spinning, fidgeting).
  • Not responsive to verbal cues or eye contact.
  • Difficulty in social situations (understanding idioms).
  • Difficulties in expressing their own needs.
  • Deficiencies in symbolic thinking.
  • Attachment to objects over people.
  • Self-injurious behaviors.
  • Echolalia.
  • Intellectual 'disability' (70%).
• Levels of Impairment:
  • Level 3: Requiring very substantial support.
  • Level 2: Requiring substantial support.
  • Level 1: Requiring support.
  • (Level 0: No support).
• Related Conditions:
  • Asperger's Syndrome: Milder form of autism with no language or cognitive delay; often above average intelligence.
  • Pervasive Developmental Disorder - Not Otherwise Specified (PDD-NOS): Autism symptoms that don't meet the full diagnostic criteria.

Empathy

• Definition: The ability to sense, understand, and share other people's emotions.
• Two Main Types:
  • Cognitive Empathy:
    • Reading body language and facial expressions.
    • Imagining what others are feeling.
    • Impaired in autism.
    • Not impaired (or even better) in Antisocial Personality Disorder and Psychopaths.
  • Affective Empathy (Emotional Empathy):
    • Appropriate emotional response to others' feelings.
    • Caring about how others feel.
    • Not impaired in autism.
    • Impaired in Antisocial Personality Disorder and Psychopaths.

Empathizing vs. Systemizing

• Systemizing:
  • Understanding, predicting, and constructing rule-based systems.
  • Focus on objects rather than people.
  • Strong pattern recognition.
  • Opposite of Empathizing (Wright and Skagaberg, 2012).
• Types:
  • Type E (Empathizing): 30%
  • Type S (Systemizing): 30% (Autism is associated with extreme Type S; common in STEM fields).
  • Balanced: 30%
  • Has a Genetic basis (Wright and Skagaberg, 2012).

Neurodiversity

• Perspective: Autism as hypersystematizing, which is valuable for society.
• Abilities:
  • Better at recognizing sounds.
  • Strong pattern recognition.
• Examples:
  • Israeli army hires autistic people to review intelligence footage.
  • Skills valuable in systems-oriented tasks involving patterns and repetition.

Neuroscience of Autism

• Brain Size:
  • Starts slightly larger in childhood (ages 3-10).
  • Ends up slightly smaller in adulthood.
  • Differences primarily in Frontal and Temporal lobes (Cortical thickness).
  • Amygdala: May be enlarged, but data is inconclusive (Ha et al., 2015; Donovan + Basson, 2017).
• Amygdala's Main Role:
  • Emotional memory (classical conditioning).
• Cerebellum
  • Reduced size and number of cells in Autism.
  • Meaning is unclear; may relate to motor symptoms in autism.
  • Or indicates unknown/poorly understood roles of cerebellum in behavior.
• Cerebellum Function:
  • Coordination of movement (not initiation or selection).
  • Motor learning.
  • Motor predictions.
  • Narrowing range of motor options.
• Motor Coordination Role:
  • Cerebral (Motor) Cortex: What should happen.
  • Muscles: What actually happens.
  • Cerebellum: Corrections and predictions.
  • Spinal Cord.
• Cerebellum and Neurons:
  • The brain has 86 billion neurons.
  • 69 billion are in the cerebellum.
• Cerebellum Damage:
  • Results in Ataxia (wide gait, instability).
  • Dysmetria (inability to coordinate complex motor activity).
  • Dysdiadochokinesia (inability to perform rapid alternating movements).
• Cerebellar Cognitive Affective Syndrome:
  • Patients with cerebellar damage may show cognitive deficits.
  • Deficits in executive function, linguistic processing, spatial cognition, affect regulation, and personality change.
  • Cerebellar damage associated with autism-like symptoms.
• Dysmetria of Thought:
  • The cerebellum optimizes performance by modulating behavior around a homeostatic baseline automatically, implicitly, and according to context.
  • Motor, emotional, and cognitive functions.
  • Moderates and coordinates; does not generate.
  • Makes predictions about the immediate future.

Attention to Faces in Autism

• Reduced attention to faces.
• Reduced activity in the Fusiform Face Area when viewing faces.
• Slower processing of faces (also seen in parents and siblings).
• More likely to focus on the mouth and peripheral cues rather than the eyes.

Brain Regions Implicated in Autism

Summary

• Neurogenesis: Constant, modest, important for learning and antidepressants.
• Social Cognition: Working out what other people are thinking.
• Autism: Social Cognition is different; characterized by lacking Cognitive Empathy (but not Affective Empathy), highly systematizing, and involves many brain regions.