The human primary visual cortex (V1) encodes the perceived position of static but not moving objects

Area of Science:

• Neuroscience
• Visual Perception
• Computational Neuroscience

Background:

• Retinotopic cortex activity can reflect illusory changes in stimulus position.
• The extent to which this neural signature represents a general code for apparent position remains unclear.

Purpose of the Study:

• To investigate whether neural responses in primary visual cortex (V1) encode apparent position across different visual illusions.
• To determine if the neural signature observed for one illusion generalizes to others.

Main Methods:

• Recorded brain activity in the primary visual cortex (V1) during exposure to visual stimuli.
• Analyzed neural responses in relation to the perception of the Muller-Lyer illusion and the curveball effect.

Main Results:

• Neural responses in V1 were consistent with the perception of the Muller-Lyer illusion.
• No corresponding neural signature for apparent position was found for the curveball effect.
• This dissociation indicates a limitation in V1's role in encoding apparent position.

Conclusions:

• Primary visual cortex (V1) activity reflects apparent position for certain illusions like the Muller-Lyer effect.
• The absence of a similar signature for the curveball effect demonstrates that V1 does not encode apparent position per se.
• The neural coding of apparent position is likely more complex and may involve higher visual areas.