Longitudinal microstructural changes in 18 amygdala nuclei resonate with cortical circuits and phenomics

Area of Science:

• Neuroscience
• Neuroimaging
• Human Brain Anatomy

Background:

• The amygdala's role in processing threats and opportunities is crucial but its subregion functions remain unclear.
• Understanding amygdala subregion plasticity and its neural network connections is vital for characterizing its role in behavior.

Purpose of the Study:

• To quantify plastic changes in 18 amygdala subregions using longitudinal data.
• To investigate structural coupling between amygdala nuclei and other brain regions.
• To associate amygdala plasticity with a wide range of phenome-wide profiles.

Main Methods:

• Longitudinal analysis of brain morphometry and behavioral data from over 1400 UK Biobank participants (age 40-69).
• Quantification of microanatomical changes in 18 amygdala subregions.
• Statistical analysis to identify coupled changes in neural systems and associated phenotypes.

Main Results:

• Specific amygdala nuclei (basal, lateral, accessory basal, paralaminar) showed synchronized changes with the prefrontal cortex.
• Other nuclei (central, medial, cortical) coupled with the salience network, basal ganglia, and visual/somatosensory areas.
• Amygdala plasticity correlated with diverse phenotypes including social status, sleep, and risk-taking behavior.

Conclusions:

• Distinct amygdala nuclei exhibit unique plasticity patterns coupled with specific neural systems.
• These structural changes are associated with a broad spectrum of human behaviors and traits.
• The findings provide a foundation for hypotheses on the functional specialization of human amygdala subregions.