Developmental Variation in Amygdala Volumes: Modeling Differences Across Time, Age, and Puberty.

Area of Science:

• Neuroscience
• Developmental Neuroscience
• Brain Imaging

Background:

• The amygdala undergoes significant development, but the precise pattern of this change is not fully understood.
• Existing research presents conflicting evidence regarding amygdala volume changes, suggesting linear, curvilinear, or no significant effects.
• This study aimed to establish a normative reference for left and right amygdala development.

Purpose of the Study:

• To identify normative trajectories of left and right amygdala volume development.
• To differentiate the effects of age and longitudinal growth on amygdala development.
• To provide a reference for typical amygdala growth patterns in youth.

Main Methods:

• Utilized data from the National Institutes of Health MRI Study of Normal Brain Development.
• Included participants aged 5 to 18 years (mean age 11.37 years) at baseline, with 54% females.
• Analyzed magnetic resonance imaging (MRI) data to assess amygdala volumes over time.

Main Results:

• Age at initial scan significantly influenced the rate of amygdala volume growth.
• Steeper amygdala growth slopes were observed in individuals scanned at younger ages.
• Left amygdala growth became non-significant around 13.1 years, and right amygdala around 14.5 years, indicating earlier peak growth for the left.

Conclusions:

• Amygdala volume shows rapid increases in early life, decelerating as individuals enter adolescence.
• Growth patterns suggest a potential for slight volume decreases in late adolescence or early adulthood.
• Findings contribute to understanding normative brain development and age-related changes in the amygdala.