Noise-Driven Feature Enhancement of High-Frequency SSVEP through Underdamped Second-order Stochastic Resonance Energy Transfer

Brain-computer interfaces (BCIs) system leveraging high-frequency steady-state visual evoked potentials (SSVEP) enhance user comfort, but their signals suffer from significant amplitude attenuation, which challenges precise detection. To address this, we proposed a novel weak-feature enhancement framework, FBUSSR-CCA, which integrates a monostable (single-well) underdamped second-order stochastic resonance (USSR) model into the filter-bank processing pipeline. This model strategically converts noise energy to nonlinearly amplify weak, high-frequency target components. Validation was performed on two public high-frequency SSVEP datasets (stimulus frequencies of 40-43Hz and 40-41.5Hz, respectively). The proposed FBUSSR-CCA was compared against six benchmark methods, including the best-performing FBCCA. Results indicated that the proposed framework attained superior performance across all three experimental conditions: the mean accuracy and ITR reached 83.61 ± 13.16 % / 17.92 ± 7.81 bits min⁻¹, 98.89 ± 2.17 % / 28.77 ± 2.30 bits min⁻¹, and 70.27 ± 19.02 % / 11.88 ± 8.62 bits min⁻¹, respectively. Further analysis confirmed the USSR module is a general-purpose tool (enhancing all six methods) and is parametrically robust to perturbations. These findings show that the monostable USSR framework is a reliable solution for enhancing high-frequency SSVEP, advancing the potential for more comfortable and efficient BCI systems.