Cerebellum development during childhood and adolescence: a longitudinal morphometric MRI study

Abstract

In addition to its well-established role in balance, coordination, and other motor skills, the cerebellum is increasingly recognized as a prominent contributor to a wide array of cognitive and emotional functions. Many of these capacities undergo dramatic changes during childhood and adolescence. However, accurate characterization of co-occurring anatomical changes has been hindered by lack of longitudinal data and methodologic challenges in quantifying subdivisions of the cerebellum. In this study we apply an innovative image analysis technique to quantify total cerebellar volume and 11 subdivisions (i.e. anterior, superior posterior, and inferior posterior lobes, corpus medullare, and three vermal regions) from anatomic brain MRI scans from 25 healthy females and 25 healthy males aged 5-24 years, each of whom was scanned at least three times at approximately 2-year intervals. Total cerebellum volume followed an inverted U shaped developmental trajectory peaking at age 11.8 years in females and 15.6 years in males. Cerebellar volume was 10% to 13% larger in males depending on the age of comparison and the sexual dimorphism remained significant after covarying for total brain volume. Subdivisions of the cerebellum had distinctive developmental trajectories with more phylogenetically recent regions maturing particularly late. The cerebellum's unique protracted developmental trajectories, sexual dimorphism, preferential vulnerability to environmental influences, and frequent implication in childhood onset disorders such as autism and ADHD make it a prime target for pediatric neuroimaging investigations.

Figure 1

Figure 1a: Cerebellar Subregions, Hemispheric lobes and vermal lobes Example of an image as processed with BRAINS, acquired with a 1.5 Tesla; typical image, the quality reflects that machine and protocol are unchanged since 1990.

Figure 2

Individual data of total cerebellar volume by age and gender Boys Girls Observations from one individual are connected by lines

Figure 3

Developmental trajectories of total cerebral and total cerebellar volume Boys —— Boys, upper 95% CI Boys, lower 95% CI Girls Girls, upper 95% CI Girls, lower 95% CI Indicates age of peak volume

Figure 4

Developmental trajectories of cerebellar hemispheric lobes, central white matter and vermis Boys —— Boys, upper 95% CI Boys, lower 95% CI Girls Girls, upper 95% CI Girls, lower 95% CI Indicates age of peak volume