Face stimuli effectively prevent brain-computer interface inefficiency in patients with neurodegenerative disease.

OBJECTIVES

Recently, we proposed a new stimulation paradigm for brain computer interfaces (BCI) based on event-related potentials (ERP), i.e. flashing characters with superimposed pictures of well-known faces. This new face flashing (FF) paradigm significantly outperformed the commonly used character flashing (CF) approach, i.e. simply highlighting characters.

METHODS

In the current study we assessed the impact of face stimuli on BCI inefficiency in patients with neurodegenerative disease, i.e. on their inability to communicate by means of a BCI. Healthy participants (N = 16) and those with neurodegenerative disease (N = 9) performed spelling tasks using CF and FF paradigms.

RESULTS

Online performance with FF was significantly increased as compared to CF in both, healthy and impaired users. Importantly, two patients who were classified "highly inefficient" with the classic CF stimulation were able to spell with high accuracy using FF. Our results particularly emphasize great benefit of the FF paradigm for those users displaying low signal-to-noise ratio of the recorded ERPs in the classic stimulation approach.

CONCLUSION

In conclusion, we confirm previously reported results now systematically validated in an online setting and display specifically beneficial effects of FF for motor-impaired users.

SIGNIFICANCE

The FF paradigm thus constitutes a big step forward against the BCI inefficiency phenomenon.