Face-Selective Patches in Marmosets Are Involved in Dynamic and Static Facial Expression Processing

Area of Science:

• Neuroscience
• Primatology
• Cognitive Science

Background:

• Facial expression recognition is crucial for social interactions in primates.
• Understanding the neural basis of facial expression processing in New World monkeys is vital for comparative studies.

Purpose of the Study:

• To investigate the neural network activated by facial expressions in awake common marmosets using ultra-high-field fMRI.
• To determine the effect of facial motions on this neural network.
• To explore the role of the face-patch network in processing facial expressions.

Main Methods:

• Ultra-high-field functional magnetic resonance imaging (fMRI) at 9.4 Tesla.
• Utilized awake, behaving common marmosets (Callithrix jacchus) of both sexes.
• Presented static and dynamic facial expressions to participants.

Main Results:

• Facial expressions (static and dynamic) activated face patches in temporal and frontal areas, as well as the amygdala.
• Negative facial expressions elicited stronger neural responses and increased respiration rates.
• Dynamic facial expression processing involved an extended network beyond known face-processing regions, suggesting motion aids recognition.

Conclusions:

• Face-selective brain patches in marmosets are involved in both face detection and facial expression processing.
• The perception and identification of facial expressions recruit these patches and are associated with increased arousal.
• Facial motion processing may enhance the recognition of facial expressions in marmosets, vital for social communication.