Neurophysiological signatures reflect differences in visual attention during absence seizures

Area of Science:

• Neuroscience
• Pediatric Neurology
• Clinical Electrophysiology

Background:

• Absence seizures in children can manifest with variable impairments in visual attention and eye movements.
• Understanding the neural underpinnings of these variations is crucial for effective clinical management.

Purpose of the Study:

• To investigate if variations in visual attention and eye movement symptoms during absence seizures correlate with distinct electroencephalographic (EEG) features.
• To explore differences in functional connectivity and frontal eye field (FEF) activation between patients with preserved versus disrupted eye movements.

Main Methods:

• Simultaneous EEG and eye-tracking were recorded in pediatric patients performing a computerized choice reaction time task during absence seizures.
• Quantification of visual attention and eye movements included reaction times, response correctness, and EEG analysis.
• Brain network analysis focused on seizure generation and propagation, including source reconstruction and graph analysis of specific EEG channels.

Main Results:

• Patients with disrupted eye movements during absence seizures showed significantly greater involvement of the right frontal eye field compared to those with preserved eye movements.
• EEG source reconstruction revealed differences in FEF activation (1.02% vs. 0.34% dipole fraction).
• Graph analysis indicated distinct functional connectivity patterns between specific EEG channels in the two groups.

Conclusions:

• The variability in visual attention impairment during absence seizures is linked to differences in EEG characteristics, brain network activation, and right frontal eye field involvement.
• These findings highlight the heterogeneous nature of absence seizures and their impact on visual processing.