Visual spatial attention control in an independent brain-computer interface

• Published in: IEEE transactions on biomedical engineering Vol. 52; no. 9; pp. 1588 - 1596
• Main Authors: Kelly, S.P., Lalor, E.C., Finucane, C., McDarby, G., Reilly, R.B.
• Format: Journal Article
• Language: English
• Published: United States IEEE 01.09.2005; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Adult; Algorithms; Application software; Attention - physiology; Biological control systems; Brain; Brain computer interfaces; Communication Aids for Disabled; Communication system control; Computer Systems; Covert attention; Decision making; Diagnosis, Computer-Assisted - methods; Electroencephalography; Electroencephalography - methods; Europe; Evoked Potentials, Visual - physiology; Eyes & eyesight; Feasibility Studies; Frequency; Humans; independent BCI; Middle Aged; Muscles; Space Perception - physiology; Steady-state; steady-state VEP; User-Computer Interface; Visual Cortex - physiology
• ISSN: 0018-9294; 1558-2531
• DOI: 10.1109/TBME.2005.851510

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.