Interhemispheric difference for upright and inverted face perception in humans: an event-related potential study

Area of Science:

• Neuroscience
• Cognitive Psychology
• Visual Perception

Background:

• Face perception involves specialized neural mechanisms.
• The N170 component is a key event-related potential (ERP) marker for face processing.
• Interhemispheric differences in face perception remain incompletely understood.

Purpose of the Study:

• To investigate interhemispheric differences in the N170 component during upright and inverted face perception.
• To explore the impact of visual field presentation on face processing asymmetries.
• To elucidate the neural dynamics underlying the face inversion effect.

Main Methods:

• Recorded event-related potentials (ERPs) in fifteen healthy subjects.
• Presented upright and inverted faces to the left and right visual hemifields.
• Analyzed the N170 component's latency and amplitude across hemispheres.

Main Results:

• The face inversion effect (prolonged latency, enhanced amplitude) was observed bilaterally.
• N170 peak latency showed no significant interhemispheric difference for upright or inverted faces.
• A significantly shorter interhemispheric time difference was found for inverted faces presented to the left hemifield.

Conclusions:

• The left hemisphere may process inverted faces more rapidly.
• Unique interhemispheric processing dynamics are involved in inverted face perception.
• Hemifield presentation of stimuli reveals novel insights into N170 face processing asymmetries.