Revealing Whole-Brain Causality Networks During Guided Visual Searching.

Area of Science:

• Neuroscience
• Cognitive Science
• Visual Perception

Background:

• Active vision involves using eye movements to gather environmental information.
• Understanding how goal-directed behavior influences brain mechanisms for active vision is crucial.
• Existing research has limited insight into neural network changes during distinct active vision tasks.

Purpose of the Study:

• To investigate changes in interregional brain interactions during two forms of active vision: free viewing and guided visual search.
• To identify brain regions and networks critical for visual processing and attention guidance.
• To explore the role of specific brain regions in modulating eye movement control during goal-directed tasks.

Main Methods:

• Combined magnetoencephalography (MEG) with eye-tracking technology in 31 participants.
• Identified fixation-related evoked activity (FRA) using spatiotemporal cluster permutation testing.
• Analyzed interregional interactions using generalized partial directed coherence.

Main Results:

• A highly connected bilateral network (posterior insula, transverse temporal gyri, superior temporal gyrus, supramarginal gyrus) emerged during free viewing.
• A similar network, centered on the right supramarginal gyrus, was observed during guided visual search.
• Activity in the right supramarginal gyrus correlated negatively with search response times, suggesting its role in updating the attention priority map.

Conclusions:

• The identified brain regions are vital for visual processing and attention guidance.
• The right supramarginal gyrus acts as a central hub for information exchange during visual search.
• Hypothesize that the right supramarginal gyrus provides information to the supplementary eye field to guide eye movements in goal-directed tasks.