Hemispheric differences over frontal theta-band power discriminate between stimulus- versus memory-driven saccadic...

Area of Science:

• Neuroscience
• Cognitive Neuroscience
• Electrophysiology

Background:

• Theta band activity is implicated in visuospatial attention tasks.
• The role of theta power in planning, execution, and cognitive control of saccadic eye movements (SEMs) remains under-investigated.

Purpose of the Study:

• To investigate the role of frontal theta power during the planning, execution, and cognitive control of SEMs.
• To examine absolute theta power over the frontal cortex during random and fixed SEMs.

Main Methods:

• Quantitative electroencephalography (qEEG) was used to record brain activity in twelve healthy volunteers.
• Participants performed tasks involving planning, execution, and cognitive control of SEMs under different conditions.
• Analysis focused on absolute theta power over frontal electrodes (F3, F4, Fz) at various time points.

Main Results:

• An interaction between SEM condition and electrode, along with main effects of time and electrode, was observed.
• Stimulus presentation led to differential patterns of frontal theta power increase between the left and right hemispheres.
• Distinct theta power patterns were identified for memory- versus stimulus-driven SEMs.

Conclusions:

• Right and left frontal regions play a crucial role in discriminating between memory- and stimulus-driven SEMs.
• These findings suggest differential contributions of frontal regions to visuospatial attention during SEMs.
• This study provides novel insights into the electrophysiological underpinnings of saccadic eye movements and attention.