In the Eye of the Illusion: Variation in Perceptual Phenomena Within an Inverted Percept

Area of Science:

• Visual perception
• Cognitive psychology
• Neuroscience

Background:

• Monocular depth cues can induce illusory depth and perspective reversals in 3D objects.
• Perceptual inversion of 3D objects typically inverts stimuli on their inner surfaces.
• The effect on stimuli within the enclosed space of reversible objects remains unexplored.

Purpose of the Study:

• To investigate the perceptual fate of stimuli within the enclosed space of a perceptually reversible 3D object.
• To compare the perception of vertical heights for stimuli on the inner surface versus suspended centrally within a truncated pyramidal chute.

Main Methods:

• Participants compared the relative vertical heights of stimuli.
• Stimuli were placed either laterally on the inner surface or centrally within the enclosed volume of a truncated pyramidal chute.
• The phenomenon of perceptual inversion was examined for both lateral and central stimuli.

Main Results:

• Lateral stimuli exhibited the typical perspective reversal.
• Central stimuli, suspended within the chute's volume, did not invert.
• Participants reported a significant compression of perceptual depth for central stimuli, despite their veridical vertical order.

Conclusions:

• The perceptual inversion illusion is diluted within the central volume of a perceptually reversible object.
• Stimuli within the enclosed space of a reversible object maintain their veridical orientation.
• Depth perception within enclosed spaces is influenced differently than surface-based stimuli during object reversal.