Emotion separation is completed early and it depends on visual field presentation.

Area of Science:

• Neuroscience
• Visual Perception
• Cognitive Psychology

Background:

• The visual system responds rapidly to stimuli, activating numerous brain areas within 100 milliseconds.
• The extent of detail processed in early visual stages remains unclear.

Purpose of the Study:

• To investigate the speed and neural mechanisms of facial emotion recognition within the early visual processing stages.
• To determine if the visual field location influences the processing of emotional facial expressions.

Main Methods:

• Magnetoencephalography (MEG) was used to record brain activity in seven healthy males.
• Participants viewed happy, fearful, and neutral faces presented centrally and peripherally.
• Neural activity was analyzed to pinpoint the timing and location of emotion separation.

Main Results:

• Facial emotions were successfully separated within 100 ms for centrally presented stimuli.
• Early processing involved the right superior temporal sulcus (STS), right amygdala, and medial pre-frontal cortex.
• Peripheral face presentation led to emotion separation in the ipsilateral amygdala and contralateral STS.

Conclusions:

• The amygdala and STS play distinct roles in early visual processing of facial emotions.
• The amygdala facilitates rapid, sub-cortical responses for survival decisions (fight or flight).
• The STS supports cognitive appraisal and integrates information across cortical areas.