Executive Dysfunction

• Ability to control action
• Includes physical movement, attention, & thoughts
• Action control includes creating plans, executing plans, staying on topic, & shifting attention
• Can be related to Monotropism theory of multitasking, with ASD not being able to sustain dual focus

Weak Central Coherence

• impaired ability to integrate information to make coherent global picture.
• Focus instead on small details
• Regarded as Islet of Ability (e.g. Savant)
• Navon test of local vs. global perception (H’s & big A)
• Theorists suggest integrating analysis of neurological short range over –connectivity and long range under connectivity
• Also integrate Neurological continuum: Hyper & Hypo Reactivity

Mind Blindness (ToM)

• Ability to imagine a set of states in another person’s mind from observing their behavior.
• Example: If someone looks out the window we infer they have seen something of interest, and that they might know something related to a want or need.
• Pertains to a great extent about reading others’ intentions from gestures and speech
• Research indications:
(a) Impaired Joint Attention: ASD child point less, look up at faces less, do not turn to follow another person’s gaze as much as typical 14 month child.
(b) Impaired Pretend Play compared to 24-month child.
(c) Do not pass Seeing Leads to Knowing Test (Two children standing by a box, one looking in and the other not.) Age 3 norm.
(d) Difficulty with False Belief Sally-Anne Test (4 year old norm). Should be called Perspective Taking.
(e) Do not understand Deception (4 year old norm)
(f) Second Order Mindreading (6 year old norm) In Sally-Anne Scenario, Anne may be depicted as looking through a keyhole when she leaves the room (Sally thinks Anne doesn’t know she has moved the marble.)
(g) Impaired ability to know what hurts another person’s feelings (9 year old norm.)
(h) Impaired ability to interpret facial expressions and read emotions conveyed by another’s eyes.

Empathizing-Systemizing Theory

• ASD low scores on Empathy (Affective) Quotient Scale (compared to other groups)
• Systemizing in classic autism:

Sensory Systemizing
Tapping surfaces, letting sand run through fingers, sniffing people, eating the same food over and over

Motoric Systemizing
Spinning, rocking, twiddling a straw

Collectible Systemizing, Numerical Systemizing, Motion Systemizing,
Spatial Systemizing, Environmental Systemizing, Social Systemizing,
Numerical Systemizing, Mechanical Systemizing, Natural
Systemizing, Vocal. Auditory/ Verbal Systemizing, Systemizing Action
Sequences, Musical Systemizing.

The contention here is that:
Executive Function Theory = Something in brain broken or undeveloped

Weak Central Coherence Theory = Some function missing in brain so that ASD drawn to detailed information due to alleged inability go integrate.

Systemizing Theory = Systemizing is result of intelligent behavior, a different cognitive style

Magnocellular Theory

• specific impairment in visual magnocellular pathway to the brain that is responsible for processing motion
• ASD slower at flicker pedestal test, in which 4 squares are presented at increasing speed and S has to indicate appearance of each square
• Problem: ASD have multi-sensory issues and also magnocellular abnormalities found in other conditions such as dyslexia.

Extreme Male Brain Theory

• Regions of the brain that are smaller in males than females but even smaller in ASD: Anterior Cingulate, Superior Temporal Gyrus, Inferior Frontal Gyrus
• Regions in brain bigger in males than females but even bigger in ASD: Amygdala (early childhood), overall brain size& weight, head circumference.

Mirror Neuron Theory

• Discovered when electrodes in brain measuring activity in animals detected mirrored neuronal activity in animals watching activities of others.
• Viewed in neuroscience as key to the neurology of empathy.
• When autistic children make facial expressions indicating emotion or look at the face of others, there is less activity in the pars opercularis of the inferior frontal gyrus.

Current Research

• ASD now viewed as a host of biologically distinct disorders
• 10% of autism cases secondary to pervasive genetic disorder such as Fragile-X
• Genetic component significant but not determining in all cases – identical twins have same DNA but sometimes only one twin is autistic.
• Autism Genome Project. International consortium of 50 universities collected data on 2000 families with multiple cases. Also 220 pairs of twins of which one twin has autism.
• 5% of autistic children have a chromosomal abnormality that can be seen under a microscope.
• We all have small regions of DNA that are duplicated or deleted, which are minor imperfections. Within the genetic structure of this DNA people can end up with one or three copies of the genes instead of two-called copy number variants.A region of Chromosome 16 containing 25 genes is deleted or duplicated in 1 – 2 % of children with autism- called copy number variants. “ Some CNV’s were inherited from a parent, others arose spontaneously, due to a genetic error in the sperm or egg.”
• Stanford Research: Take skin cells from subtypes of autism defined by genes and Chromosome 16CNV, turn them into stem cells, use proteins to shape a neural tube which is the earliest neural structure to form, later become the spinal cord and brain. They then create facsimiles of the cortex and heart so that they can experiment with known problems such as:
Heart Arrhythmia ( Timothy Syndrome) –try different drugs
Too many cells producing dopamine and norepinephrine
Too few cells that form long distance connections & too many that form
Short-term connections.
• Thomas Sudhoff researching synapse proteins that have a role in “ synapse plasticity”, which underlie learning and memory.
• For example Fragile-X syndrome ( one third are autistic) are missing a protein that helps regulate synaptic function. There is an excess of signaling that may lead to intellectual disabilities. So they experiment with drugs that can “dampen the noise.”
• MRI Spectroscopy shows some autistic children have increased thickness of cortex, which disappears randomly, & so they explore which genes are related to this.
• Karen Parker exploring biomarkers in blood and cerebro-spinal fluid related to the biology of social functioning. Oxytocin is a hormone that promotes social bonding. 13 autistic adults were given Oxytocin nasal spray and subsequently exhibited greater ability to read social cues and make eye contact.

Polyvagal Theory

Not discussed in the culture of autism, but has a place in pediatric medical discussion of autism. Research has demonstrated afferent nerve connections between the Polyvagal Nerve (12th cranial nerve) and a “ Social Engagement System consisting of nerves and muscles responsible for head turning, facial expression etc. as well as connections to the stomach and heart. The Vagal nerve impacts sinus rhythm as well as the parasympathetic nervous system. There are major implications in terms or hyperarousal, hypoarousal, chronic medical problems, and social engagement.