Autism, fear, casein and immunisations.
Autism is increasingly being associated with the following:
1. Abnormal immune system within the brain.
2. Abnormal genetic make-up.
3. Structural abnormalities of neurons or nerve cells.
4. Recognised substances which cause the abnormal immuno-genetic response. These are either environmental (immunogens)e.g. thalidomide, rubella, valproate or made by the body e.g. phenyl alanine (auto-immunogens).
5. Abnormal MRI/functional MRI scans.
These lead to the clinical features of autism:
1. Self-obsession. Obsession-compulsion.
2. Sensory hyper/hyposensitivity. Motor under/overactivity.
3. Extreme ideas, thoughts, feelings, behaviour – more often negative than positive.
4. Variation in intelligence.
One of the main problems in autism is excessive fear often related to change. This results in many of the clinical features i.e.
1. Fear of people – new faces, voices, accents, body shapes, behaviour.
2. Fear of places – new school, new routes to school, holiday destinations.
3. Fear of things – large or small, fast or slow, bright or dark, heights, speed.
These are often made worse by sensory hyper/hyposensitivity.
Where does fear come from?
Increased activity in the outer amygdala (an almond shaped deeper part of the brain) is associated with increased fear. Usually the frontal lobes (the front of the brain) over-ride the amygdala. The amygdala and frontal lobes have the most opioid or narcotic receptors in the brain.
Increased outer amygdala activity is associated with “fight, fright or flight” behavioural responses. The amygdala is connected to the frontal lobes and sympathetic nervous system which controls heart rate, breathing, bowel function and sweating.
What happens to the amygdala and frontal lobes in autism?
The amygdalae are often larger in children with autism. Functional MRI scans have shown that the amygdalae remain activated for longer in adults with autism who are shown a series of faces.
Functional MRI scans have shown that the frontal lobes are more active in certain areas in children with autism when they are solving puzzles.
There is increasing evidence of an imbalance between the amygdala and frontal lobes in autism.
How could immunisations affect the amygdala?
In 2010 Hewitson et al published their study of the effect of the US childhood vaccine schedule (1994-1999) on
1. Amygdala size.
2. Opioid receptors in the amygdala and frontal lobes
They found that
1. Immunised monkeys did not undergo the MRI scan maturational changes over time in amygdala volume that was observed in unimmunised monkeys.
2. Binding of opioid – blockers to opioid receptors in the amygdalae remained constant in the immunised group but decreased in the unimmunised group.
They concluded that
“.. the results of this pilot study warrant additional research into the potential impact of an interaction between the MMR and thimerosal-containing vaccines on brain structure and function. Additional studies are underway in the primate model to investigate the mechanistic basis for this apparent interaction.”
How may these findings apply to the treatment of autism?
Some children with autism are treated with casein-free diets. Casein is found in milk. Casein breaks down in the stomach to produce the peptide casomorphin. Casomorphin has an opioid effect.
The Cochrane review of gluten- and casein-free diets for autistic spectrum disorder found that social isolation and overall ability to communicate and interact could improve, but that further well-designed trials were necessary as there were only two randomly controlled clinical trials.
Perhaps some children with autism have
1. Increased amygdalae volumes
2. Increased amygdalae activity
3. Increased numbers of unoccupied opioid receptors in the amygdalae
which contribute to the amygdalae over-riding the frontal lobes resulting in this fear-based disease.
The US Childhood Immunisation programme 1994-1999 when used in monkeys affected the amygdalae maturation and opioid receptors and will need further research.
Casein-free diets may help by reducing casomorphin exposure to the opioid receptors in the amygdalae.
Heightened Level Of Amygdala Activity May Cause Social Deficits In Autism
Diffusion Tensor Imaging of Frontal Lobe in Autism Spectrum Disorder
Influence of pediatric vaccines on amygdala growth and opioid ligand binding in rhesus macaque infants: A pilot study
Gluten- and casein-free diets for autistic spectrum disorder