The Necker cube--an ambiguous figure disambiguated in early visual processing

Area of Science:

• Neuroscience
• Cognitive Psychology
• Visual Perception

Background:

• Perceptual reversals occur with unchanging stimuli, such as ambiguous figures (e.g., Necker cube).
• Explanations involve either early visual processing (bottom-up) or later cognitive factors (top-down).
• Electroencephalography (EEG) offers high temporal resolution for studying neural correlates of perception.

Purpose of the Study:

• To pinpoint the precise timing of neural correlates associated with endogenous perceptual reversals.
• To differentiate between early visual processing and later cognitive influences on perceptual change.

Main Methods:

• Development of a novel experimental paradigm to accurately measure perceptual reversals.
• Utilizing electroencephalography (EEG) to record event-related potentials (ERPs) with high temporal precision.
• Analysis of early occipital ERP signals time-locked to spontaneous perceptual shifts.

Main Results:

• Identification of an early occipital event-related potential (ERP) signal.
• This ERP signal was detected at approximately 120 milliseconds post-stimulus onset.
• The early ERP signal showed a significant correlation with endogenous perceptual reversals.

Conclusions:

• The findings suggest that early visual processing plays a crucial role in spontaneous perceptual reversals.
• An early neural signal (120 ms) is associated with the shift in perception of ambiguous figures.
• Further exploration of parallels between ambiguous figure reversals and binocular rivalry is warranted.