Objective: The aim of this study was to investigate EEG metrics in patients with CACNA1A and GAA-FGF14 related diseases and to compare them with those of healthy controls (HC).

Background: CACNA1A variants and GAA-FGF14 ataxia share overlapping neurological phenotypes, including chronic cerebellar signs and episodic ataxia. There is sparse evidence linking CACNA1A mutations to altered resting-state electroencephalogram (EEG) patterns, and no data for GAA-FGF14 ataxia.

Method: Resting-state EEGs were analyzed in 29 CACNA1A, 15 GAA-FGF14 ataxia patients, and 30 HC. Patient EEGs were recorded using the 10-20 system, bandpass-filtered (0.5–40 Hz), and segmented into 2-second epochs. Artifacts were removed via independent component analysis. Band power was calculated using Welch’s method, and functional connectivity was assessed via weighted Phase-Lag Index (wPLI) and Minimum Spanning Tree (MST) metrics. Bayesian linear regression was used to assess genotype effects, adjusting for age and sex differences.

Results: Delta and theta power were increased in CACNA1A patients compared to both GAA-FGF14 patients and HC. GAA-FGF14 patients consistently showed higher beta and gamma power than CACNA1A patients and HC. Functional connectivity analysis revealed significantly increased overall wPLI in the theta and delta bands in CACNA1A patients compared to HC. In addition, MST metrics were increased in CACNA1A patients, indicating a higher degree of centralization.

Conclusion: Distinct resting-state EEG alterations characterize CACNA1A and GAA-FGF14 ataxias, reflecting unique network-level effects of P/Q-type calcium channel dysfunction. Advanced EEG analysis shows potential as a biomarker for calcium channelopathies.

« Back to 2025 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/resting-state-eeg-analysis-defines-the-signature-of-cacna1a-and-gaa-fgf14-related-channelopathies/