Autism : its prenatal origin traced and redrawn in the neocortex

Trace, from development prenatal cortex or neocortex (new cortex), the irregularities of the brain related to autism could be one day possible to read and find out the findings and conclusions of this study conducted at the University of California, San Diego, and supported by the US National Institute of Mental Health (NIMH/NIH).  Because of this stage, the architecture of small brain with autism is dotted with specks or spots of abnormal neurons. These conclusions published in the New England Journal of Medicine are remarkable by the early onset of findings, a precocity primarily sought for the diagnosis of autism.

Autism is generally regarded as a brain development disorder yet this new research -if its results were to be confirmed- suggests a process and a "pathogenesis" that starts well before the birth. It is the synthesis of Dr Thomas R. Insel director of NIMH which stressed obviously the interest of discovery for identification and early intervention.
During the prenatal development of the brain, the neurons differ in 6 layers in the cortex, each layer with certain types of brain cells and patterns of specific connections. The team has been focused on the genes cellular markers of each of the cortical layers as well as on genes already known to be associated with autism.

Their work shows also that

• Some markers for several layers of the cortex are absent in 91% of samples vs 9% of samples witnesses.
• signs of disorganization are localized in areas of 5-7 mm and on several cortical layers (see the video)
• these anomalies are found in the frontal lobes and temporal cortex of zones involved in the social, emotional functions, communication, language and functions specifically deficient in autism.

The brain could rely

The analysis thus revealed areas of disorganized neurons forming the plates. The researchers suggest that the affected areas and the level of severity of the anomalies observed underlie and the expressions of the disorder and the severity of different symptoms in the child. But the hope is that the variability of the anomalies detected supports the effectiveness of early treatment. Because the anomalies do not affect the whole of the cortex and researchers suggest here that the developing brain could have a chance to repair the faulty or deficient connections by passing these abnormal brain areas .

Eventually, the study therefore provides a great hope of hyper-early and precoce diagnosis and thus of "repair".

Source: New England Journal of Medicine March 27, 2014 DOI: 10.1056/NEJMoa1307491 Patches of disorganization in the neocortex of children with autism (Visuels NIMH@ Rich Stoner, Ph.D., University of California, San Diego)- Voir la vidéo