Brain–Computer Interface — a system that lets a person communicate or control a device through brain signals alone, without muscle movement.
CCA
Canonical Correlation Analysis — finds linear combinations of two signal sets that are maximally correlated. The standard SSVEP feature when references are sine/cosine pairs at the stimulation frequencies.
DC
Direct Current — the zero-frequency component of a signal. In raw EEG it shows up as a baseline offset that needs to be removed before spectral analysis.
EEG
Electroencephalography (or Electroencephalogram) — recording of the electrical activity of the brain measured at the scalp.
FBCCA
Filter Bank CCA — an extension of CCA that splits the signal into multiple sub-bands (each capturing a harmonic of the stimulation frequency) before running CCA, then combines the per-band correlations.
ICA
Independent Component Analysis — decomposes a multi-channel signal into statistically independent sources. Used in EEG to isolate and remove artifacts such as eye blinks.
ITR
Information Transfer Rate — bits-per-minute throughput of a BCI, accounting for both classifier accuracy and trial duration. The metric that determines how usable a BCI actually is.
LDA
Linear Discriminant Analysis — a linear classifier that projects features onto the direction maximizing between-class versus within-class variance. The baseline classifier used by the g.tec tool that produced CH11.
LED
Light-Emitting Diode — the light source flickered at a fixed frequency to drive the SSVEP response.
PSD
Power Spectral Density — describes how the power of a signal is distributed across frequency. Computed here with Welch’s method.
SNR
Signal-to-Noise Ratio — power of the signal of interest divided by power of the background. Used in this book to quantify how clearly an SSVEP peak rises above the alpha rhythm.
SSVEP
Steady-State Visual Evoked Potential — the periodic, phase-locked EEG response generated by visual cortex when the eye is exposed to a flickering stimulus. The phenomenon this entire book is built on.