Contextual modulation of amygdala responsivity to surprised faces

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Affective Neuroscience

Background:

• Previous research established a link between amygdala and medial prefrontal cortex (mPFC) activity during subjective interpretation of facial expressions.
• The role of external contextual cues in modulating these neural responses remains less understood.

Purpose of the Study:

• To investigate how negatively versus positively valenced contextual sentences influence amygdala and mPFC activity when viewing surprised facial expressions.
• To determine if objective contextual stimuli, rather than subjective judgment, modulate neural responses to emotional faces.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to measure brain activity in human subjects.
• Participants passively viewed surprised faces preceded by either negative or positive contextual sentences, matched for length and arousal.
• Analysis focused on amygdala and medial prefrontal cortex (mPFC) activation patterns.

Main Results:

• Negatively cued surprised faces elicited greater activation in the ventral amygdala compared to positively cued faces.
• Ventrolateral prefrontal cortex (vlPFC) showed greater response to negative sentences, while ventromedial prefrontal cortex (vmPFC) responded more to positive sentences.
• Connectivity analyses suggested specific cortical-subcortical systems mediate this contextual modulation.

Conclusions:

• Amygdala responses to surprised facial expressions are significantly modulated by the valence of preceding verbal context.
• Contextual information plays a crucial role in shaping the neural processing of emotional facial cues.
• This study highlights the interplay between language, emotion perception, and neural circuitry involving the amygdala and mPFC.