%0 Journal Article
%T Decoding spatial attention with EEG and virtual acoustic space
%A Kaan E. Raif
%A Sarah C. Determan
%A Yan Gai
%A Yue Dong
%J Archive of "Physiological Reports".
%D 2017
%R 10.14814/phy2.13512
%X Decoding spatial attention based on brain signals has wide applications in brain¨Ccomputer interface (BCI). Previous BCI systems mostly relied on visual patterns or auditory stimulation (e.g., loudspeakers) to evoke synchronous brain signals. There would be difficulties to cover a large range of spatial locations with such a stimulation protocol. The present study explored the possibility of using virtual acoustic space and a visual©\auditory matching paradigm to overcome this issue. The technique has the flexibility of generating sound stimulation from virtually any spatial location. Brain signals of eight human subjects were obtained with a 32©\channel Electroencephalogram (EEG). Two amplitude©\modulated noise or speech sentences carrying distinct spatial information were presented concurrently. Each sound source was tagged with a unique modulation phase so that the phase of the recorded EEG signals indicated the sound being attended to. The phase©\tagged sound was further filtered with head©\related transfer functions to create the sense of virtual space. Subjects were required to pay attention to the sound source that best matched the location of a visual target. For all the subjects, the phase of a single sound could be accurately reflected over the majority of electrodes based on EEG responses of 90 s or less. The electrodes providing significant decoding performance on auditory attention were fewer and may require longer EEG responses. The reliability and efficiency of decoding with a single electrode varied with subjects. Overall, the virtual acoustic space protocol has the potential of being used in practical BCI systems
%K Auditory attention
%K brain¨C computer interface
%K EEG
%K phase
%K spatial attention
%U https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5704085/