Autism

An overview of autism-related content on Genes to Cognition Online.

There are 3 primary symptoms of autism �€“ social difficulties, communication difficulties, and repetitive behaviors. These may reflect abnormalities in brain areas, including the frontal cortex, amygdala, and cerebellum. At the cellular level, the brain�€™s mirror neuron system may be dysfunctional. Within these cells, abnormalities in the levels of biochemicals such as GABA, serotonin and, glutamate, have been reported. Many genes, which interact in complex ways, have been associated with autism. Evidence linking vaccinations to autism has been widely dismissed by the scientific community. Selected items on the Genes to Cognition Online �€œsubway line�€� explore key areas in autism research. GENES Research from twin studies provides compelling evidence that autism is a highly genetic disorder. A study by Bailey and Colleagues (1995) found that if an identical (monozygotic) twin had autism, there was a 60% likelihood that the other twin also had autism. For non-identical (dizygotic) twins this figure dropped to 0%. The search for genes for autism has been difficult however, and there is no one single gene that has been definitively linked to the disorder. Instead, it seems that a number of interacting genes are involved in the disorder. Use the Chromosome Map of Disorders and Processes to explore some of the prominent genes associated with autism. CHEMICALS One of the genes associated with autism is GABRB3, a GABA receptor gene. GABA is the primary inhibitory neurotransmitter in the brain, and a number of studies have found an association between autism and abnormalities in GABA levels. Serotonin and glutamate are other neurotransmitters linked to autism. Researchers have struggled to understand autism at a biochemical level, and a potentially promising avenue of research is to explore the biochemistry of mirror neurons. CELLS Mirror neurons have elicited a lot of research attention as potentially important components in understanding the biological basis of autism. Mirror neurons have been called �€œempathy neurons�€� because they fire when we witness others perform particular actions and experience emotions. Individuals with autism have been found to have problems with empathy, and a dysfunctional mirror neuron system may be involved as a source of this problem. Mirror neurons have also been linked to language acquisition, and autistic individuals often have language impairments. BRAIN The frontal lobe (namely the inferior frontal gyrus) is thought to be part of the mirror neuron system. Abnormal activity in this area has been found in individuals with autism. Other neuroanatomical areas that have been linked to autism include the amygdala, which is involved in processing emotions; an enlarged brain; and abnormalities in the cerebellum. Explore these areas using the 3D brain. COGNTION Autism is a spectrum disorder, which means there are different levels and forms of autism. It is difficult to define exactly what constitutes autistic behavior, and the threshold between �€œnormal�€� and �€œautistic�€� is often not clear. The Diagnostic and Statistical Manual of Mental disorders (DSM) focuses on 3 primary symptoms of autism �€“ social difficulties, communication difficulties, and repetitive behaviors. One of the social difficulties is an inability to interpret facial expressions. Use the Reading Faces tool to explore your own ability to read facial expressions. Individuals will differ in how well they perform on this tool, just as autistic individuals differ in where they fall on the autistic spectrum. ENVIRONMENT A very controversial hypothesis about the causes of autism focuses on mercury levels in vaccines. Although this hypothesis has been widely dismissed by the scientific community, the fact that we still struggle to find specific causes for autism means the hypothesis retains advocates. The environment section also focuses on myths relating to bad parenting and social interest. You can also listen to an interview with Mark Haddon, author of the Curious Incident of the Dog in the Night-time.

autism, symptoms, research, mirror neuron system, inhibitory neurotransmitter, frontal cortex, gaba receptor, biochemical level, social difficulties, research attention, communication difficulties

  • ID: 1975
  • Source: DNALC.G2C

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2239. Language

An overview of language-related content on Genes to Cognition Online.

  • ID: 1975
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  • Source: G2C

908. Autism Candidate Genes

Use this chromosome map to explore genes associated with autism.

  • ID: 1975
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  • Source: G2C

916. GABRB3 Gene

GABA is the main inhibitory neurotransmitter in the adult brain. GABRA3 is a candidate gene for autism.

  • ID: 1975
  • Type:
  • Source: G2C

1288. Neuroimaging and Autism

Neuroimaging studies of autism highlight a dysfunctional mirror neuron system, particularly in an area called the ventrolateral prefrontal cortex.

  • ID: 1975
  • Type:
  • Source: G2C

2224. ADHD

An overview of ADHD-related content on Genes to Cognition Online.

  • ID: 1975
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  • Source: G2C

840. Brain and Autism

Abnormal activity in specific brain regions has been associated with autism spectrum disorders.

  • ID: 1975
  • Type:
  • Source: G2C

872. Autism Neuropathology

Autism is not associated with any single deficit in the brain.

  • ID: 1975
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  • Source: G2C

1173. Glutamate and Schizophrenia

Professor Daniel Weinberger discusses evidence from a number of research areas that highlight the importance of the neurotransmitter glutamate in schizophrenia.

  • ID: 1975
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  • Source: G2C

852. Mirror Neurons and Empathy

Empathy, research indicates, is made possible by a special group of nerve cells called mirror neurons.

  • ID: 1975
  • Type:
  • Source: G2C

1972. Mirror neurons and autism

Professor Christian Keysers discusses the proposed association between autism and mirror neurons, a very hot topic in autism research.

  • ID: 1975
  • Type:
  • Source: G2C