Scientists also have discovered irregularities in the brain structures themselves, such as in the corpus callosum which facilitates communication between the two hemispheres of the brain , amygdala which affects emotion and social behavior , and cerebellum which is involved with motor activity, balance, and coordination. They believe these abnormalities occur during prenatal development. A brain-tissue study suggests that children affected by autism have a surplus of synapses, or connections between brain cells.
The excess is due to a slowdown in the normal pruning process that occurs during brain development, researchers say. Autistic children and adults typically have problems with social interactions and verbal and nonverbal communications.
It regulates thought, emotion, and our physiological processes. What do we really know…. Autism affects everyone differently depending on its severity. We have found the best autism blogs that support individuals, families, and carers. What does autism look like in the brain? Written by Maria Cohut, Ph. Share on Pinterest What happens in the brains of people with autism?
Overly persistent brain connections. Exposure to air pollutants may amplify risk for depression in healthy individuals. Costs associated with obesity may account for 3. Related Coverage. Multiple studies have shown that vaccination to prevent childhood infectious diseases does not increase the risk of autism in the population.
Twin and family studies strongly suggest that some people have a genetic predisposition to autism. Identical twin studies show that if one twin is affected, then the other will be affected between 36 to 95 percent of the time. There are a number of studies in progress to determine the specific genetic factors associated with the development of ASD. In families with one child with ASD, the risk of having a second child with the disorder also increases.
Many of the genes found to be associated with autism are involved in the function of the chemical connections between brain neurons synapses. Researchers are looking for clues about which genes contribute to increased susceptibility. In some cases, parents and other relatives of a child with ASD show mild impairments in social communication skills or engage in repetitive behaviors.
Evidence also suggests that emotional disorders such as bipolar disorder and schizophrenia occur more frequently than average in the families of people with ASD. The mutation then occurs in each cell as the fertilized egg divides. These mutations may affect single genes or they may be changes called copy number variations, in which stretches of DNA containing multiple genes are deleted or duplicated.
Recent studies have shown that people with ASD tend to have more copy number de novo gene mutations than those without the disorder, suggesting that for some the risk of developing ASD is not the result of mutations in individual genes but rather spontaneous coding mutations across many genes.
De novo mutations may explain genetic disorders in which an affected child has the mutation in each cell but the parents do not and there is no family pattern to the disorder. Autism risk also increases in children born to older parents. There is still much research to be done to determine the potential role of environmental factors on spontaneous mutations and how that influences ASD risk. For many children, symptoms improve with age and behavioral treatment.
During adolescence, some children with ASD may become depressed or experience behavioral problems, and their treatment may need some modification as they transition to adulthood. People with ASD usually continue to need services and supports as they get older, but depending on severity of the disorder, people with ASD may be able to work successfully and live independently or within a supportive environment.
There is no cure for ASD. Therapies and behavioral interventions are designed to remedy specific symptoms and can substantially improve those symptoms. The ideal treatment plan coordinates therapies and interventions that meet the specific needs of the individual. Most health care professionals agree that the earlier the intervention, the better. In these interventions therapists use highly structured and intensive skill-oriented training sessions to help children develop social and language skills, such as applied behavioral analysis, which encourages positive behaviors and discourages negative ones.
In addition, family counseling for the parents and siblings of children with ASD often helps families cope with the particular challenges of living with a child with ASD. Antipsychotic medications are used to treat severe behavioral problems.
Seizures can be treated with one or more anticonvulsant drugs. Medication used to treat people with attention deficit disorder can be used effectively to help decrease impulsivity and hyperactivity in people with ASD.
In both groups, networks of brain regions increased and decreased their activity in predictable patterns. But in individuals with autism, sensory areas of the brain showed more random activity than in individuals without autism. The most random activity occurred in those with the most severe autism. This suggests that the brains of people with autism cannot hold onto and process sensory input for as long as those of neurotypical people.
By contrast, a brain region called the caudate showed the opposite pattern, being more predictable in individuals with autism.
The most predictable caudate activity occurred in those individuals with the most inflexible, repetitive behaviors.
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