AUTISM is a puzzling phenomenon that is seen in people of otherwise normal—sometimes above normal—intelligence. However, it is often associated with other problems, and can also appear in mild and severe forms. This variability has led many people to think of it as a spectrum of symptoms rather than a single, clear-cut syndrome. And that variability makes it hard to work out what causes it. Researchers say that individuals with Autism Spectrum Disorders are either disinterested in social interactions or find them unpleasant. Sadly, persons with autism spectrum disorders are often painfully aware of their limited sociability, which can lead to profound feelings of sadness and frustration.
CAUSES: Several causes have been attributed to its presence:
- A defective SHANK3 gene, which is a human gene on chromosome 22.This gene is a member of the Shank gene family. Shank proteins are present in the brain nerve cells and connect impulses from one nerve cell to the other. Shank proteins also play a role in synapse formation i.e.the points of contact between nerve cells.
Researchers from Mount Sinai School of Medicine have found that when one copy of the SHANK3 gene in mice is missing, nerve cells do not effectively communicate and do not show cellular properties associated with normal learning.
- They also found altered functional and structural plasticity in nerve cells, which is a cellular measure of the flexibility that occurs during learning, and in the synapses.
- So, while there is evidence of genetic influence, but no clear pattern of inheritance, one suggestion that does pop up from time to time is that the process which leads to autism involves faulty mitochondria. The mitochondria are a cell’s power packs. They disassemble sugar molecules and turn the energy thus liberated into a form that biochemical machinery can use. Mitochondrial faults could be caused by broken genes, by environmental effects, or by a combination of the two. If faulty mitochondria do turn out to be a cause of autism, even if not in all cases, that question will have to be investigated.
Nerve cells have a huge demand for energy, so a failure of the mitochondria would certainly affect them. The question is, could it cause autism?
- Mitochondria from children with autism consumed far less oxygen than those from the control group:
Dr Giulivi of the University of California conducted a study on 10 autistic children versus a control group of 10 normal children. She found that mitochondria from children with autism consumed far less oxygen than those from the control group. That is a sign of lower activity. One important set of enzymes—NADH oxidases—used, on average, only a third as much oxygen in autistic children as they did in non-autists, and eight of the autistic children had significantly lower NADH-oxidase activity than is normal.
- The mitochondria of the autistic children also leaked damaging oxygen-rich chemicals such as hydrogen peroxide.
These are a normal by-product of mitochondrial activity, but are usually mopped up by special enzymes before they can escape and cause harm—for instance, by damaging a cell’s DNA. The level of hydrogen peroxide in the cells of autistic children was twice that found in non-autists. Such high levels suggest the brains of autistic children are exposed to a lot of oxidative stress, something that would probably cause cumulative damage.
DIAGNOSIS: A new scanning technique via MRI, allows an accurate diagnosis of the condition to be made in only 10 minutes.
Researchers at Harvard University have made a vital breakthrough in the early diagnosis of autism which shows how the different parts of the brain interact.
Autism sufferers have weaker brain connections.
The scan shows how well water molecules move along the “wiring”, which links different parts of the brain. From the images, doctors will be able to measure the interaction within the areas of the brain and thus make a diagnosis.
- Scientists have found that some symptoms of autism can be alleviated by a nasal spray containing oxytocin, the “bonding” hormone.
People with autism who inhaled the spray altered their behavior temporarily, becoming more sociable and trusting.
“Under oxytocin, patients with high-functioning autism respond more strongly to others and exhibit more appropriate social behavior,” wrote Elissar Andari, of the Institut des Sciences Cognitives, a French government centre for neuroscience research, in a summary of a recent conference presentation.
- The drug baclofen, which is, in various for has in fact been shown to affect oxytocin. “We published a paper last year showing that baclofen strongly activated oxytocin in the rat brain,”
- Researchers at the Eastern Virginia Medical School are testing an antibiotic, D-Cycloserine, suggesting it can alter the function of certain receptors in the brain known to affect sociability and help the animals be more at ease around others.
- Sensory Integration Therapy: Sensory Integration is the process through which the brain organizes and interprets external stimuli such as movement, touch, smell, sight and sound. Autistic children often exhibit symptoms of Sensory Integration Dysfunction (SID) making it difficult for them to process information brought in through the senses. The goal of Sensory Integration Therapy is to facilitate the development of the nervous system’s ability to process sensory input in a more typical way. Through integration the brain pulls together sensory messages and forms coherent information upon which to act . SIT uses neurosensory and neuromotor exercises to improve the brain’s ability to repair itself. When successful, it can improve attention, concentration, listening, comprehension, balance, coordination and impulsivity control in some children.
- Speech Therapy: The communications problems of autistic children vary to some degree and may depend on the intellectual and social development of the individual. Some may be completely unable to speak whereas others have well-developed vocabularies and can speak at length on topics that interest them. Any attempt at therapy must begin with an individual assessment of the child’s language abilities by a trained speech and language pathologist.
- Occupational Therapy: Occupational Therapy can benefit a person with autism by attempting to improve the quality of life for the individual. The aim is to maintain, improve, or introduce skills that allow an individual to participate as independently as possible in meaningful life activities. Coping skills, fine motor skills, play skills, self help skills, and socialization are all targeted areas to be addressed.
- Healing Dynamics: Craniosacral therapy has proven effective in the treatment of Autism. Children with autism feel virtually trapped within themselves. Typically, autistic children have a very tight cranium with no “give”. They often seem to have very severely compressed temporal bones bilaterally and virtually locked occipital sutures. Treatment aims at releasing these sutures and setting free the bones of the cranium. Other treatment methods incorporated in a session include: neurodevelopmental therapy and visceral manipulation.
EVMS’ laboratory studies on mice have led investigators to hypothesize that D-Cycloserine could ease the impaired sociability of people with autism, such as avoiding eye contact and personal interaction. Those traits can severely limit the possibility of employment and independent living.