Typical development of basal ganglia, hippocampus, amygdala and cerebellum from age 7 to 24

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Neuroimaging

Background:

• Cortical grey matter development is well-studied, but subcortical region development remains less understood.
• Longitudinal studies on subcortical brain development are scarce.
• Subcortical regions include the caudate, putamen, pallidum, accumbens, thalamus, amygdala, hippocampus, and cerebellar cortex.

Purpose of the Study:

• To investigate the developmental trajectories of subcortical brain structure volumes.
• To analyze age-related changes in subcortical grey matter using longitudinal data.
• To compare developmental patterns across different subcortical regions and between sexes.

Main Methods:

• Utilized FreeSurfer's automatic labeling for subcortical volume estimation.
• Analyzed 223 magnetic resonance imaging (MRI) scans from 147 participants (ages 7.0-24.3).
• Included longitudinal data from 53 participants scanned multiple times.

Main Results:

• Observed significant diversity in developmental trajectories among subcortical structures.
• Caudate, putamen, and nucleus accumbens volumes decreased with age.
• Hippocampus, amygdala, pallidum, and cerebellum showed inverted U-shaped trajectories; thalamus had a slight initial increase then decrease.
• Males generally had larger subcortical volumes than females, with a sexually dimorphic trajectory for the cerebellum.

Conclusions:

• Subcortical structures continue to mature through adolescence, similar to the cerebral cortex.
• Significant heterogeneity exists in the developmental timing and patterns of subcortical brain regions.
• Findings highlight the complex and varied maturation processes of subcortical brain development into early adulthood.