Detection of high-frequency steady state visual evoked potentials using phase rectified reconstruction

Brain-computer interfaces (BCIs) based on the steady state visual evoked potential (SSVEP) can provide higher bitrates and require shorter training than other BCIs. The oscillating visual stimulus required to elicit an SSVEP can be (depending on the stimulation frequency) annoying for the user and even dangerous since it can trigger photoepileptic seizures. These issues can be surmounted by using high-frequency stimulation (beyond 40 Hz). However, the nature of the SSVEP is such that it decreases with increased stimulation frequency. Conventional spectral methods are not always suitable for detecting high-frequency SSVEPs. In this paper, it is shown that the recently developed phase rectified reconstruction average (PRSA) technique effectively detects SSVEPs elicited by stimulation frequencies between 43 and 46 Hz.