title: Visual spatial attention control in an independent brain-computer interface.
abstract: This paper presents a novel brain computer interface (BCI) design employing visual evoked potential (VEP) modulations in a paradigm involving no dependency on peripheral muscles or nerves. The system utilizes electrophysiological correlates of visual spatial attention mechanisms, the self-regulation of which is naturally developed through continuous application in everyday life. An interface involving real-time biofeedback is described, demonstrating reduced training time in comparison to existing BCIs based on self-regulation paradigms. Subjects were cued to covertly attend to a sequence of letters superimposed on a flicker stimulus in one visual field while ignoring a similar stimulus of a different flicker frequency in the opposite visual field. Classification of left/right spatial attention is achieved by extracting steady-state visual evoked potentials (SSVEPs) elicited by the stimuli. Six out of eleven physically and neurologically healthy subjects demonstrate reliable control in binary decision-making, achieving at least 75% correct selections in at least one of only five sessions, each of approximately 12-min duration. The highest-performing subject achieved over 90% correct selections in each of four sessions. This independent BCI may provide a new method of real-time interaction for those with little or no peripheral control, with the added advantage of requiring only brief training.
authors.affiliation: Department of Electronic & Electrical Engineering, University College Dublin, Belfield Dublin 4, Ireland. simon.kelly@ee.ucd.ie
authors.forename: Simon P
authors.initials: SP
authors.lastname: Kelly
authors.forename: Edmund C
authors.initials: EC
authors.lastname: Lalor
authors.forename: Ciarán
authors.initials: C
authors.lastname: Finucane
authors.forename: Gary
authors.initials: G
authors.lastname: McDarby
authors.forename: Richard B
authors.initials: RB
authors.lastname: Reilly
mesh_terms: D000328:Adult; D000465:Algorithms; D001288:Attention / Q000502:physiology*; D003143:Communication Devices for People with Disabilities; D003199:Computer Systems; D003936:Diagnosis, Computer-Assisted / Q000379:methods; D004569:Electroencephalography / Q000379:methods*; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005240:Feasibility Studies; D006801:Humans; D008875:Middle Aged; D013028:Space Perception / Q000502:physiology*; D014584:User-Computer Interface; D014793:Visual Cortex / Q000502:physiology*