Brain Development

New Mouse Model Mimics Brain Abnormalities in Autism

Source: 
Simons Foundation Autism Research Initiative
Date Published: 
October 6, 2014.
Abstract: 

Mice with mutations in the autism-linked gene WDFY3 have enlarged brains reminiscent of those seen in some children with autism, finds a study published in Nature Communications. The brain overgrowth begins in the womb, the study found. WDFY3 plays a role in autophagy, a process that rids cells of damaged or unneeded parts. Mouse embryos with two copies of the mutant gene have enlarged brains and an excess of immature neurons that divide faster than usual. They also have misdirected patches of neurons. Similar changes have been observed in people with autism.

Method Reveals Relationship Between White, Gray Matter

Source: 
Simons Foundation Autism Research Initiative
Date Published: 
August 27, 2014
Abstract: 

A new technique helps researchers trace the nerve fibers that connect brain regions by revealing how the fibers physically relate to curves and folds on the brain’s surface. The method was described in Medical Image Analysis. The technique examines the relationship between white matter, composed of nerve fibers and support cells, and gray matter, which is largely made of the cell bodies of the neurons the fibers sprout from. Preliminary findings support the theory that autism involves early, hyperconnected and dense brain growth before an abnormal decline, the researchers say.

Maternal antibodies from mothers of children with autism alter brain growth and social behavior development in the rhesus monkey

Source: 
Translational Psychiatry
Date Published: 
July 9, 2013

Recent studies have produced findings that suggest that immunoglobulin G (IgG) class antibodies cross the placenta during pregnancy and affect brain development. Researchers believe that this may lead to one form of ASD. The activity of IgG antibodies was monitored in groups of female rhesus monkeys during their first and second trimesters of pregnancy. Results demonstrated there were differences in white matter volume in IgG-ASD offspring, and these differences were most prominent in the frontal lobes. 

Atypical Cross Talk Between Mentalizing and Mirror Neuron Networks in Autism Spectrum Disorder

Source: 
JAMA Psychiatry
Date Published: 
April 16, 2014
Abstract: 

Atypical brain connectivity in areas that affect social interactions have been found in people with autism spectrum disorders. This difference in connectivity is found in networks of the brain that help individuals understand what others are thinking, and to understand others' actions and emotions. Up until now, it was thought that these areas of the brain were under-connected in people with autism, but this study shows that more often than not, they are actually over-connected. The study also found that the greater the difference in neural connectivity, the more social interactions were impaired.

Neurobehavioural Effects of Developmental Toxicity

Source: 
The Lancet
Date Published: 
February 14, 2014
Abstract: 

Neurodevelopmental disabilities, including autism, attention-deficit hyperactivity disorder, dyslexia, and other cognitive impairments, affect millions of children worldwide, and some diagnoses seem to be increasing in frequency. A new study in The Lancet states that industrial chemicals that injure the developing brain are among the known causes for this rise in prevalence. Building on a 2006 study in which researchers identified five industrial chemicals as developmental neurotoxicants (lead, methylmercury, polychlorinated biphenyls, arsenic, and toluene), epidemiological studies have documented six additional developmental neurotoxicants — manganese, fluoride, chlorpyrifos, dichlorodiphenyltrichloroethane, tetrachloroethylene, and the polybrominated diphenyl ethers. To protect children from exposure to such harmful chemicals, researchers say that untested chemicals should not be presumed to be safe to brain development.

RNA Bits Vary in Social, Auditory Brain Areas in Autism

Source: 
Simons Foundation Autism Research Institute
Date Published: 
November 14, 2013
Abstract: 

People with autism show differences from controls in the levels of microRNAs, small noncoding bits of RNA, in the social and sound-processing parts of the brain. MicroRNAs, or miRNAs, bind to messenger RNAs, which code for protein, and flag them for degradation. Each miRNA can interfere with the production of several proteins. Of the more than 5,000 miRNAs and other small noncoding RNAs that the researchers screened, they found 3 miRNAs that are dysregulated in these regions in people with autism compared with controls.

Yale Researchers Find Genetic Links to Autism

Source: 
Cell
Date Published: 
November 21, 2013
Abstract: 

Scientists at Yale have identified which types of brain cells and regions of the brain are affected by genetic mutations linked to autism spectrum disorders. Researchers state that this new discovery has the potential for new types of autism treatments. We may not need to treat the whole brain, they say; only particular areas of the brain may be affected by autism at certain times.

Genetic Analysis Links Autism to Missing Brain Structure

Source: 
Simons Foundation Autism Research Institute
Date Published: 
November 14, 2013
Abstract: 

The largest genetic analysis yet conducted of people lacking a brain structure called the corpus callosum shows that the condition shares many risk factors with autism. The study was published PLoS Genetics. The corpus callosum is the thick bundle of nerve fibers that connects the two hemispheres of the brain. People lacking this structure, a condition called agenesis of the corpus callosum (AgCC), often have social impairments, and roughly one-third of adults meet diagnostic criteria for autism. Children with autism seem to have a smaller corpus callosum than controls do.

Autism Affects Sexes Differently

Source: 
Brain
Date Published: 
June 7, 2013
Abstract: 

A Cambridge study that used brain imaging samples of individuals with autism, led by Dr. Simon Baron-Cohen, found evidence that autism affects sexes differently. The study showed that women who have the condition demonstrate “neuroanatomical masculinization”, which suggests that women with autism have more masculine brains.

Dr. Baron-Cohen argues that this study reinforces that researchers "should not blindly assume that everything found in males with autism applies to females."

News Article: http://www.cambridge-news.co.uk/Education/Universities/Autism-affects-se...

Problematic Antibodies Affecting Brain Development During Pregnancy Could Help Explain 1/4 of Cases of Autism

Source: 
Translational Psychiatry
Date Published: 
July 9, 2013
Abstract: 

Antibodies found almost exclusively in mothers with children who have autism have a certain anitbody that may be affecting brain development during pregnancy. The same study says that these antibodies could account for nearly 1/4 of all cases of autism.