tailieunhanh - Báo cáo khoa hoc:" Brain-computer interfacing using modulations of alpha activity induced by covert shifts of attention"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành y học dành cho các bạn tham khảo đề tài: Brain-computer interfacing using modulations of alpha activity induced by covert shifts of attention | Uillíl JOURNAL OF NEUROENGINEERING AND REHABILITATION Brain-computer interfacing using modulations of alpha activity induced by covert shifts of attention Treder et al. Treder et al. Journal of NeuroEngineering and Rehabilitation 2011 8 24 http content 8 1 24 5 May 2011 BioMed Central Treder et al. Journal of NeuroEngineering and Rehabilitation 2011 8 24 http content 8 1 24 Iril JOURNAL OF NEUROENGINEERING NCR AND REHABILITATION RESEARCH Open Access Brain-computer interfacing using modulations of alpha activity induced by covert shifts of attention Matthias S Treder 1 Ali Bahramisharif2 3 Nico M Schmidt1 Marcel AJ van Gerven2 3 and Benjamin Blankertz1 Abstract Background Visual brain-computer interfaces BCIs often yield high performance only when targets are fixated with the eyes. Furthermore many paradigms use intense visual stimulation which can be irritating especially in long BCI sessions. However BCIs can more directly directly tap the neural processes underlying visual attention. Covert shifts of visual attention induce changes in oscillatory alpha activity in posterior cortex even in the absence of visual stimulation. The aim was to investigate whether different pairs of directions of attention shifts can be reliably differentiated based on the electroencephalogram. To this end healthy participants N 8 had to strictly fixate a central dot and covertly shift visual attention to one out of six cued directions. Results Covert attention shifts induced a prolonged alpha synchronization over posterior electrode sites PO and O electrodes . Spectral changes had specific topographies so that different pairs of directions could be differentiated. There was substantial variation across participants with respect to the direction pairs that could be reliably classified. Mean accuracy for the best-classifiable pair amounted to . Furthermore an alpha power index obtained during a relaxation measurement showed to be .