What is SSVEP?

When the visual cortex is driven by a flickering light at frequency f, neurons synchronize and produce an EEG response at f and its harmonics (2f, 3f …).

Strongest at occipital electrodes (Oz, O1, O2) overlying the primary visual cortex (V1).

BCI Applications

SSVEP is ideal for Brain–Computer Interfaces:

• No training needed
• High SNR
• Multiple targets
• ITR up to ~5 bits/s

Controls

• Click an LED to fixate
• Slider below each LED to set its frequency (1–30 Hz)

Observe peaks at f₀, 2f₀, 3f₀ in the PSD.

Try setting two LEDs to the same frequency to see peak merging!