A child’s cortex thickens during his/her childhood and starts to thin again after reaching its peak. According to a new study, the more intelligent a child is, the later he/she will experience this peak.

This study was carried out at the National Institute of Mental Health in Bethesda, Maryland, USA, and was led by Philip Shaw.

The scientists monitored cortex development of 307 children using MRI scans during the children’s early years right through into their later teens. They found that children whose IQs were over 121 reached maximum cortex thickness at 11 years’ of age, while other children reached the same point when they were 6. Intelligent children, whose IQs did not reach 121, reached maximum cortex thickness when they were 9.

As all the children matured beyond maximum cortex thickness age, the cortex began to thin.

We don’t know why this happens. The scientists do not know whether the factors that influence this are genetic, environmental (upbringing and simulation by the family) or a combination of both.

Written by: Christian Nordqvist
Editor: Medical News Today