«Dissociation of Trait-like and State-like Biomarkers in Motor Imagery EEG: Validation of the Task-Specific Focal Frequency (fc) Model»

Description :

This publication presents the validation of the task‑specific focal frequency (fc) model, demonstrating the dissociation of trait‑like and state‑like biomarkers in motor‑imagery EEG.

Using the BCI Competition IV Dataset 2a (subject A01), a two‑stage hierarchical framework was implemented:

Stage 1 identified a stable trait‑level focal frequency (fc = 10.17 ± 0.29 Hz; reliability ≈ 0.97) distinct from the resting‑state individual alpha frequency (IAF = 10.74 ± 0.17 Hz; Δ = −0.58 Hz, p < 0.05).

Stage 2 estimated event‑related desynchronization (ERD) and phase‑locking value (PLV), revealing lower stability for PLV (0.72–0.79), confirming its state‑like nature.

A mixed‑effects analysis confirmed statistical independence between ERD amplitude and PLV timing (all p > 0.33).

These findings provide convergent neurophysiological evidence that motor‑imagery EEG encodes two orthogonal information channels: a trait‑level focal frequency and a state‑level synchrony—laying the foundation for personalized, fatigue‑resistant BCIs.

Authors: Hamed Almasi‑Baklani (ORCID: 0009‑0006‑0916‑8143)

Affiliation: Independent Researcher, Signal Processing & Cognitive EEG

Contact: fanm.neurosystems@gmail.com

All scientific and intellectual property rights for the focal‑frequency (fc) biomarker framework are solely owned by Hamed Almasi‑Baklani (2025).

Any reuse or derivative work requires the author’s written consent.

Integrity Hash (SHA‑256): 02191aaa7e6e8d5f55a193dec02aeee7b3aa5580b57171e22b411af703d52dcc

Filename: Focal Frequency (fc) Model.pdf

Date: 2025‑11‑14