Eye movements modulate the spatiotemporal dynamics of word processing.

Area of Science:

• Cognitive Neuroscience
• Visual Perception
• Reading Science

Background:

• Active reading involves coordinated eye movements (saccades) and fixations.
• Previous neuroimaging studies often used constant eye fixation, limiting understanding of saccade impact on word processing.

Purpose of the Study:

• To investigate the effects of eye movements, specifically saccades, on word recognition processes.
• To explore the neural mechanisms underlying postsaccadic word processing.

Main Methods:

• Used anatomically constrained magnetoencephalography (aMEG) and psychophysical measurements.
• Incorporated real-time saccade detection to analyze word recognition relative to eye movements.
• Compared effects of saccades with background movement mimicking saccades.

Main Results:

• Word recognition was slower and brain responses were reduced for words presented shortly after saccades.
• Neural response reductions were observed early in visual cortices and later in language regions.
• Similar effects were found with background motion, suggesting retinal motion's role, while differences indicated central mechanism contributions.

Conclusions:

• Saccades induce a transient impairment in word processing.
• Both retinal motion and central saccadic mechanisms interact to modulate postsaccadic processing during reading.
• This highlights a complex interplay influencing reading efficiency.