Impacts du poids à la naissance et du génotype sur le développement des circuits attentionnels

Chercheurs-boursiers cliniciens -Junior 1 | Concours 2012-2013

Sherif Karama

Université McGill


Domaine : Neurosciences, santé mentale et toxicomanies

There is compelling evidence that the origins of multiple forms of mental illness lie in early development. For instance, restricted fetal growth, which is mainly related to potentially avoidable maternal health risk factors and reflected in low birth weight, predicts an increased risk for multiple disorders associated with emotional and cognitive function. Of these, the clearest evidence is for a strong relation between birth weight and the risk for ADHD, and more specifically, for the attentional deficits of ADHD. Despite the well-known link between low birth weight and increased risk for ADHD, not all children with low birth weight show signs of ADHD. It is here suggested that genetic background influences the impact of birth weight on the development of the attentional network that is frequently affected in subjects with ADHD.

The proposed research program, which aims to better understand the mechanisms that link low birth weight to increased risk for ADHD, will be conducted through the participation of the Montreal subsample (sample size of more than 250 children) of the high-risk Maternal Adversity, Vulnerability and Neurodevelopment (MAVAN) cohort established in 2003 to thoroughly investigate the effects of variations in early life conditions on the developing brain. Subjects will be scanned yearly (for those between the ages of 6 and 13 years) to study how the structure and function of their brains develop. The guiding hypothesis is that the impacts of birth weight on brain development is influenced by genetic background and that these impacts will be most apparent among children bearing genes that have been frequently associated with increased risk for ADHD.