"Scene" from inside: The representation of Observer's space in high-level visual cortex

Area of Science:

• Neuroscience
• Cognitive Science
• Visual Perception

Background:

• Human observers perceive scenes as enclosures, with the observer physically inside.
• Previous research suggested high-level visual cortices, like the parahippocampal place area (PPA), process scene boundaries.
• PPA showed sensitivity to closed versus open spatial boundaries in scenes.

Purpose of the Study:

• To investigate the neural representation of scene spatial boundaries.
• To determine if PPA's sensitivity to boundary openness reflects landscape type or observer's spatial position.
• To compare the processing of scene boundaries in the PPA and occipital place area (OPA).

Main Methods:

• Two human functional magnetic resonance imaging (fMRI) experiments were conducted.
• Participants viewed scenes with varying spatial boundaries.
• Neural activity in visual cortices, specifically PPA and OPA, was analyzed.

Main Results:

• Both PPA and OPA processed scene boundaries based on the observer's spatial context (inside vs. outside) rather than landscape openness (e.g., forest vs. beach).
• PPA activation patterns were affected by mid-level perceptual scene properties, such as rectilinear patterns.
• OPA responses were not susceptible to these mid-level perceptual manipulations.

Conclusions:

• Scene boundary processing in PPA and OPA is primarily driven by the observer's spatial location.
• The observer's position significantly influences the neural representation of spatial boundaries in scenes.
• PPA exhibits greater sensitivity to perceptual scene properties compared to OPA, highlighting distinct roles in scene perception.