The body inversion effect is mediated by face-selective, not body-selective, mechanisms

Area of Science:

• Neuroscience
• Cognitive Psychology
• Human Body Perception

Background:

• The brain possesses specialized mechanisms for processing human bodies, evidenced by body-selective brain areas and the behavioral body inversion effect (BIE).
• The BIE, which involves poorer discrimination of inverted versus upright bodies, diminishes for headless figures, highlighting the head's importance.
• Prior research indicates the fusiform face area mediates the face inversion effect.

Purpose of the Study:

• To investigate whether the behavioral body inversion effect (BIE) is mediated by face-selective or body-selective brain regions.
• To explore the neural underpinnings of head-related processing in human body perception.

Main Methods:

• Two event-related functional magnetic resonance-adaptation (fMRI-A) experiments were conducted.
• Participants viewed pairs of upright and inverted whole (faceless) bodies and headless bodies.
• Adaptation effects in category-selective occipitotemporal areas were analyzed.

Main Results:

• Body-selective areas exhibited similar adaptation for upright and inverted bodies, irrespective of the head's presence.
• Face-selective areas showed adaptation to upright but not inverted bodies, and for whole but not headless bodies.
• Neural responses in face-selective areas mirrored behavioral BIE patterns.

Conclusions:

• Face-selective brain areas, not body-selective areas, are critical for mediating the behavioral body inversion effect.
• The head plays a significant role in the neural processing of human body orientation.
• These findings elucidate the distinct neural pathways involved in processing body parts versus whole body configurations.