Sex-contingent face aftereffects depend on perceptual category rather than structural encoding.

Area of Science:

• Neuroscience
• Perceptual Psychology
• Computational Vision

Background:

• Visual adaptation studies reveal how recent sensory experiences modify perception.
• Face perception is influenced by adaptation, typically making adapted faces seem more normal.
• Simultaneous opposite aftereffects across categories suggest complex neural processing.

Purpose of the Study:

• To differentiate between category-contingent and structure-contingent adaptation in face perception.
• To investigate the neural mechanisms underlying sex-contingent face aftereffects.
• To determine if adaptation affects neurons coding perceptual categories or physical features.

Main Methods:

• Experimentally induced visual adaptation using face stimuli.
• Compared adaptation effects between distinct sex categories (male/female).
• Compared adaptation effects within a single sex category (female/hyper-female) with matched structural differences.

Main Results:

• Opposite aftereffects were successfully induced following adaptation between male and female face categories.
• No opposite aftereffects were observed following adaptation within the female category (female/hyper-female).
• Structural differences were mathematically equivalent across both adaptation conditions.

Conclusions:

• Findings support category-contingent adaptation, involving neurons selective for perceptual categories (e.g., sex).
• Results cannot be explained by structure-contingent adaptation of lower-level neurons coding physical face patterns.
• Perceptual categorization plays a crucial role in sex-contingent face aftereffects.