Perisaccadic mislocalization without saccadic eye movements

Area of Science:

• Neuroscience
• Cognitive Science
• Visual Perception

Background:

• The brain uses eye position signals to stabilize vision during saccadic gaze shifts.
• Briefly flashed stimuli during saccades are mislocalized, showing spatial shifts and compression.
• This perisaccadic mislocalization is often attributed to eye position signal timing errors.

Purpose of the Study:

• To investigate perceptual mislocalization during actual saccades and simulated saccades.
• To determine if mislocalization patterns differ when extraretinal eye position signals are absent.
• To explore the role of visual reference frames in perisaccadic spatial distortions.

Main Methods:

• Human observers performed saccadic eye movements.
• Retinal image motion was simulated using a fast display shift during fixation.
• Perceptual mislocalization (shift and compression) was measured in both conditions.

Main Results:

• The spatial and temporal patterns of mislocalization were similar for real and simulated saccades.
• Perisaccadic mislocalization occurred even without changes in extraretinal eye position signals.
• Visual reference frame availability influenced the degree of shift and compression.

Conclusions:

• Perisaccadic mislocalization is not solely dependent on extraretinal eye position signals.
• Difficulties in establishing a stable percept within a visual reference frame contribute to mislocalization.
• Visual references play a significant role in modulating spatial distortions during rapid visual shifts.