Structural-functional correlations between hippocampal volume and cortico-limbic emotional responses in depressed...

Area of Science:

• Neuroscience
• Developmental Psychology
• Psychiatry

Background:

• Major depressive disorder (MDD) is associated with hippocampal atrophy and altered brain responses to emotional stimuli.
• The precise relationship between hippocampal volume and functional brain activation in pediatric depression remains unclear.

Purpose of the Study:

• To investigate the association between hippocampal volume and functional brain activation in response to emotional stimuli in children.
• To examine these relationships in children with and without a history of preschool onset major depressive disorder (PO-MDD).

Main Methods:

• Utilized structural and functional magnetic resonance imaging (fMRI) in 64 nonmedicated school-aged children.
• Assessed annual diagnostic history from preschool.
• Monitored brain activity during emotional face perception tasks.

Main Results:

• Smaller bilateral hippocampal volumes correlated with increased cortico-limbic activation (amygdala, hippocampus, dlPFC) to negative versus neutral faces in the total sample.
• Left hippocampal volume showed a negative association with cortico-limbic activation in all children.
• Right hippocampal volume negatively correlated with amygdala response specifically in the PO-MDD group.

Conclusions:

• Findings suggest an interrelationship between reduced hippocampal volume and hyperactive brain responses to emotional stimuli in children.
• These patterns may be present in children with and without a history of PO-MDD, indicating potential neurobiological underpinnings.
• Highlights the importance of the hippocampus in emotional regulation during development.