Dynamic functional connectivity variability in the thalamocortical circuit: Insights from Self-Limited Epilepsy with Centrotemporal Spikes (SeLECTs)

Background

Self-Limited Epilepsy with Centrotemporal Spikes (SeLECTs) is a dominant childhood epilepsy form characterized by seizures originating from the brain’s centrotemporal region. Crucially, unlocking the neural dynamics and mechanisms underlying SeLECTs paves the way for potent diagnostic and therapeutic strategies. Our work investigates dynamic functional connectivity (dFC) variability in the thalamocortical circuit in SeLECTs individuals, thereby shedding light on the temporal dynamics and anomaly in connectivity patterns tied to seizure occurrence and propagation.

Methods

Utilizing resting-state functional magnetic resonance imaging (rs-fMRI) data from 45 SeLECTs patients and 55 healthy controls (HCs), dynamic changes in functional connectivity (FC) across various brain regions were examined over time. We selected 16 thalamic seeds to delve into dFC variability using a sliding window approach. We also evaluated clinical data from both groups to discern its correlation with dFC variability. As a final step, a Support Vector Machine (SVM) was employed for classification analysis to demonstrate the potential use of dFC variability as a distinguishing feature between SeLECTs patients and HCs.

Results

t-test analysis manifested significant variances in dFC variability between SeLECTs and HCs groups related to thalamus seeds, also showing a correlation between VCI and certain areas. Out of 16 thalamus seeds, significant variances emerged in 9 seeds. Specifically, an increase in dFC variability was observed between the right occipital thalamus seed and the right precentral gyrus in SeLECTs patients, implying a positive connectivity alteration. On the other hand, a lowered dFC was observed between the right inferior prefrontal thalamus seed and the left cuneus, reflecting a reduction in their connectivity strength.

Conclusion

Our study underscores the significance of dFC variability within the thalamocortical circuit in SeLECTs individuals. The noticeable aberrant connectivity patterns enrich our understanding of temporal dynamics linked to SeLECTs seizure occurrence and propagation, thereby contributing to understanding SeLECTs pathophysiology. These insights may steer the development of precise diagnostic and therapeutic strategies for this widespread childhood epilepsy.