The neural basis of the behavioral face-inversion effect

Area of Science:

• Cognitive Neuroscience
• Neuroimaging
• Human Face Perception

Background:

• The face-inversion effect (FIE) and fusiform face area (FFA) activation are key markers of specialized face processing.
• The relationship between the behavioral FIE and neural responses in face-selective regions remains unclear.

Purpose of the Study:

• To investigate the association between the behavioral face-inversion effect (FIE) and brain activity in face-selective regions, particularly the FFA.
• To determine if the FFA is a primary neural source of the behavioral FIE.

Main Methods:

• Functional magnetic resonance imaging (fMRI) was used to measure brain activity in response to upright and inverted faces.
• Behavioral FIE was measured through recognition accuracy for upright and inverted faces.
• Correlational analyses were performed between behavioral FIE and fMRI responses in face-selective regions (FFA, f_STS, OFA).

Main Results:

• The FFA showed a significant positive correlation between the fMRI-FIE and the behavioral FIE across subjects.
• Both FFA and f_STS exhibited greater responses to upright versus inverted faces, but only FFA showed the correlation.
• The FFA demonstrated enhanced neural sensitivity to upright face differences compared to inverted faces, suggesting a mechanism for the behavioral FIE.

Conclusions:

• The fusiform face area (FFA) is a primary neural correlate of the behavioral face-inversion effect.
• Neural mechanisms within the FFA contribute to the behavioral FIE, highlighting its role in upright face recognition.
• The findings differentiate the FFA's role from other face-selective regions like the f_STS and OFA in the context of the FIE.