bioRxiv Science⌕ Search

Biology subjects

Baumer, F.

Publications and source records attributed to Baumer, F..

2 recordsLinked to original sources

Language Dysfunction Associated with Pathological Brain Connectivity in Children with Epilepsy

Language impairment is common in childhood epilepsy and may arise in part from disruption of the distributed brain networks that support language. In self-limited epilepsy with centrotemporal spikes (SeLECTS)--the most common focal epilepsy of childhood--hyperconnectivity has been linked to poor language outcomes, but the specific network patterns associated with language dysfunction remain unclear, limiting the ability to target neurostimulation rationally. We recorded high-density EEG from 27 children with SeLECTS and 29 age-matched controls during verb generation and rest, and quantified functional connectivity across multiple frequency bands and bilateral frontal, temporal, occipital, and motor regions. Using multivariate pattern analysis, we identified connectivity patterns that predicted language ability, distinguished patterns shared across groups from those specific to SeLECTS and tested whether spatially specific connectivity provided information beyond whole-brain or hemispheric averages and conventional clinical variables. Frontal and occipitotemporal connectivity, particularly within the left hemisphere, predicted language ability across groups, whereas motor-network connectivity emerged as the dominant SeLECTS-specific predictor, linking the epileptogenic network to language dysfunction. Connectivity between specific regions outperformed averaged connectivity measures and predicted language beyond epilepsy diagnosis and antiseizure medication use. Task-based connectivity also outperformed resting-state connectivity. These findings show that language ability is associated with distributed yet spatially specific patterns of brain connectivity, while epilepsy introduces distinct alterations centered on the epileptogenic network. Identifying these disease-specific network patterns provides mechanistic insight into language dysfunction and a rational basis for spatially targeted neuromodulation.

neuroscience↗

Functional Connectivity in Self-limited Epilepsy with Centrotemporal Spikes (SeLECTS) Increases with Epilepsy Duration and Interictal Spike Exposure.

ObjectiveTo determine the impact of epilepsy duration and interictal spikes on functional connectivity in children with Self-Limited Epilepsy with Centrotemporal Spikes (SeLECTS). MethodsConnectivity was calculated from electroencephalograms (EEGs) of 68 children with SeLECTS and 65 age and sex-matched controls using the weighted phase lag index. SeLECTS EEGs were categorized by epilepsy duration (shorter or longer than 6 months) to assess progressive connectivity changes. To investigate the impact of spikes on connectivity, 19 SeLECTS patients who underwent two EEGs were analyzed longitudinally, comparing those whose spikes persisted versus resolved over time. Analyses focused on connectivity during sleep. ResultsConnectivity increased with epilepsy duration, being lowest in controls, intermediate in patients with shorter epilepsy duration, and highest in those with longer duration. Changes were initially greatest within the right occipital region and became more widespread with longer epilepsy duration. Longitudinally, patients with persistent spikes showed increasing connectivity over time, while those with spike resolution demonstrated decreasing connectivity, resulting in significant between-group differences. ConclusionsFunctional connectivity in SeLECTS increases progressively with epilepsy duration and spike exposure, suggesting that ongoing spikes drive neural network alterations. SignificanceSpikes are a potential treatment target to prevent progressive brain network disruption and preserve cognitive outcomes.

neuroscience↗