Causes of Autism
Cause of Autism: Autism has no single cause. Researchers have identified a number of genes that play a role in the disorder. In some children, environmental factors also may play a role in development of the disorder. Studies of people with autism have found abnormalities in several regions of the brain, including the cerebellum, amygdala, hippocampus, septum, and mamillary bodies. Neurons in these regions appear smaller than normal and have stunted nerve fibers, which may interfere with nerve signaling. These abnormalities suggest that autism results from disruption of normal brain development early in fetal development. Other studies suggest that people with autism have abnormalities of serotonin or other signaling molecules in the brain. While these findings are intriguing, they are preliminary and require further study. The early belief that parental practices are responsible for autism has now been disproved. 1
Cause details for Autism: It is generally accepted that autism is caused by abnormalities in brain structures or functions. Using a variety of new research tools to study human and animal brain growth, scientists are discovering more about normal development and how abnormalities occur.
The brain of a fetus develops throughout pregnancy. Starting out with a few cells, the cells grow and divide until the brain contains billions of specialized cells, called neurons. Research sponsored by NIMH and other components at the National Institutes of Health is playing a key role in showing how cells find their way to a specific area of the brain and take on special functions. Once in place, each neuron sends out long fibers that connect with other neurons. In this way, lines of communication are established between various areas of the brain and between the brain and the rest of the body. As each neuron receives a signal it releases chemicals called neurotransmitters, which pass the signal to the next neuron. By birth, the brain has evolved into a complex organ with several distinct regions and subregions, each with a precise set of functions and responsibilities. 2
Underlying condition causes of Autism: The list of possible underlying conditions (see also Misdiagnosis of underlying causes of Autism) mentioned in various sources as possible causes of Autism includes:
- Rett syndrome
- Fragile X syndrome - found in about 10% of autism cases.
- Tuberous sclerosis - about 25% of autistics.
- Congenital rubella
Causes of Autism: medical news summaries: The following medical news items are relevant to causes of Autism:
Related information for causes of Autism:
Further relevant information on causes of Autism may be found
in the risk factors for Autism
and underlying causes of Autism.
1. excerpt from Autism Fact Sheet: NINDS
2. excerpt from Autism: NIMH
Medical Tools & Articles:
- Risk Factor Center
- Medical Statistics Center
- Medical Treatment Center
- Prevention Center
- Medical Tests Center