Brain to computer interfaces (BCIs) are designed to give their users communication and control channels that do not depend on the brain's normal output channel of peripheral nerves and muscles. For these non-invasive BCIs, the most common modality has traditionally been the electroencephalography (EEG). However, one problem associated with EEG-based BCIs is that EEG is a relatively indirect measure of cognitive function. This leads to long training times, as well as frustration and anxiety for patients who struggle to operate the BCI. Other modalities, such as near infrared spectroscopy, suffer from a limited information transfer rate due to the nature of the physiological process underlying the utilized signal. In our research, we recently started assessing the possibility of a new access technology - a BCI based on changes in cerebral blood flow velocity.