Is autism hiding in a fold of the brain?

January 13, 2016
Mapping of cortical fold depths. In green: sulcal pits (the deepest point of each fold). In red: localization of the abnormality detected in autistic children (in Broca's area). Credit: SCALP team / INT

Scientists at CNRS, Aix-Marseille Université and AP-HM have identified a cerebral marker specific to autism that can be detected by MRI and is present as from the age of two years. The abnormality thus detected consists in a less deep fold in Broca's area, a region of the brain specialized in language and communication, functions that are impaired in autistic patients. This discovery may assist in the earlier diagnosis and management of these patients. It has been made possible by the medical imaging processing skills of the Institut de Neurosciences de la Timone (CNRS/Aix-Marseille Université) and access to a homogeneous cohort of patients diagnosed at a very young age and all assessed using the same protocol at the Centre de Ressources Autisme PACA. The results of their collaboration are published on 12 January 2016 in Biological Psychiatry: Cognitive Neurosciences and Neuroimaging.

The autistic spectrum covers a range of neuro-developmental disorders (typical autism, Asperger's syndrome or pervasive developmental disorders not otherwise specified) which mainly affect social relationships and communication. These disorders are associated with abnormal development of the brain. Recent neuroimaging findings have notably suggested the existence of abnormal cortical folding (the formation of convolutions on the surface of the brain). However, standard neuro-anatomical measurement techniques had failed until now to demonstrate any markers specific to each of these disorders, and notably typical autism.

Scientists at the Institut de Neurosciences de la Timone (in Marseille, France) focused on a new geometric marker called the "sulcal pit". This is the deepest point of each sulcus in the cerebral cortex, from which points all the folds on the brain's surface develop. They are therefore put in place at a very early developmental stage, probably under genetic influences, which means they are indicators adapted to comparisons between different individuals.

Based on MRI findings, the scientists observed the sulcal pits of 102 young boys aged 2 to 10 years, who were placed in three groups (those with autistic disorder, pervasive developmental disorder not otherwise specified, and typically developing children). By comparing these three groups, they discovered that in Broca's area (a region known to be involved in language and communication), the maximum depth of a sulcus was less among autistic children when compared with the other two groups. Interestingly, this highly localized atrophy was correlated with the social communication performance of children in the autistic group: the deeper the sulcal pits, the more impaired were their skills in terms of language production.

This abnormality specific to may therefore constitute a biomarker for the disease that could enable their earlier diagnosis and management, as from the age of two years. Indeed, at present, autism can only be diagnosed based on clinical signs, through the observation of children and interviews with their parents.

This study has also enabled a discovery concerning brain development. While it was previously thought that cortical folding was complete at birth, the scientists observed that some folds (the most superficial) continued to deepen with age and in an identical manner in both autistic and other children. Biomedical research may therefore help to improve our understanding of the mechanisms of life.

Explore further: New research may lead to improved diagnosis of autism

More information: Brun Lucile et al. Localized misfolding within Broca's area as a distinctive feature of autistic disorder, Biological Psychiatry: Cognitive Neuroscience and Neuroimaging (2015). DOI: 10.1016/j.bpsc.2015.11.003

Related Stories

New research may lead to improved diagnosis of autism

May 31, 2011
Functional magnetic resonance imaging (fMRI) may provide an early and objective indicator of autism, according to researchers at Columbia University in New York City, who used the technique to document language impairment ...

Weak synchronization in toddler brains may be a biological marker for autism

July 25, 2011
The biological causes of autism are still not understood. A diagnosis of autism is only possible after ages three or four; and the tests are subjective, based on behavioral symptoms. Now, in research that appeared in Neuron, ...

Team finds age-related changes in how autism affects the brain

March 13, 2013
Newly released findings from Bradley Hospital published in the Journal of the American Academy of Child & Adolescent Psychiatry have found that autism spectrum disorders (ASD) affect the brain activity of children and adults ...

Diversity in developmental trajectories in kids with autism spectrum disorder

January 28, 2015
Preschool children with autism spectrum disorder (ASD) differed from each other in symptom severity and adaptive functioning at the time of diagnosis and some of these differences appeared to increase by age 6, according ...

Tests show no specific gastrointestinal abnormalities in children with autism

February 25, 2016
Children with autism have no unique pattern of abnormal results on endoscopy or other tests for gastrointestinal (GI) disorders, compared to non-autistic children with GI symptoms, reports a study in the Journal of Pediatric ...

Do disruptions in brain communication have a role in autism?

March 21, 2013
A new study of patterns of brain communication in toddlers with autism shows evidence of aberrant neural communication even at this relatively early stage of brain development. The results are presented in an article in Brain ...

Recommended for you

Late-breaking mutations may play an important role in autism

July 17, 2017
A study of nearly 6,000 families, combining three genetic sequencing technologies, finds that mutations that occur after conception play an important role in autism. A team led by investigators at Boston Children's Hospital ...

Females with autism show greater difficulty with day-to-day tasks than male counterparts

July 14, 2017
Women and girls with autism may face greater challenges with real world planning, organization and other daily living skills, according to a study published in the journal Autism Research.

Researchers investigate possible link between carnitine deficiency and autism

July 13, 2017
Researchers are always looking for new clues to the causes of autism, with special emphasis on prevention or treatment. At Baylor College of Medicine, Dr. Arthur Beaudet has been following clinical and genetic clues in patients ...

How children look at mom's face is influenced by genetic factors and altered in autism

July 12, 2017
New research has uncovered compelling evidence that genetics plays a major role in how children look at the world and whether they have a preference for gazing at people's eyes and faces or at objects.

Oxytocin improves social abilities in some kids with autism, study finds

July 10, 2017
Children with autism showed improved social behavior when treated with oxytocin, a hormone linked to social abilities, according to a new study by researchers at the Stanford University School of Medicine. Children with low ...

Possible early diagnosis of autism spectrum disorder

June 29, 2017
Measuring a set of proteins in the blood may enable earlier diagnosis of autism spectrum disorder (ASD), according to a study from the Peter O'Donnell Jr. Brain Institute at UT Southwestern Medical Center.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.