5-HTTLPR differentially predicts brain network responses to emotional faces.

Area of Science:

• Neuroscience
• Genetics
• Psychiatry

Background:

• The 5-HTTLPR polymorphism is extensively studied for its effects on amygdala reactivity to emotional faces.
• Less is known about its impact on broader brain network responses during emotional face processing.

Purpose of the Study:

• To investigate 5-HTTLPR genotype differences in whole-brain responses to emotional faces.
• To examine emotion-specific effects of 5-HTTLPR on neural networks.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used in 76 healthy adults.
• Participants viewed neutral, angry, and fearful faces.
• Whole-brain analysis examined differences between 5-HTTLPR genotype groups.

Main Results:

• Emotional faces robustly activated the amygdala, hippocampus, caudate, fusiform gyrus, STS, and lateral prefrontal/occipito-parietal cortices.
• LA/LA individuals showed increased response to angry faces only, while S' carriers responded to both angry and fearful faces.
• LA/LA individuals had a greater response to angry faces, whereas S' carriers had a greater response to fearful faces.

Conclusions:

• Findings reveal emotion-specific 5-HTTLPR effects on distributed brain regions involved in emotion and face processing.
• Provides insight into neurobiological mechanisms linking 5-HTTLPR genotype to personality and neuropsychiatric illness risk.