A High-Throughput Auditory P300 Interface for Everyone

TitleA High-Throughput Auditory P300 Interface for Everyone
Publication TypeConference Paper
Year of Publication2013
Conference Name12th European AAATE Conference
AuthorsVamvakousis, Z., & Ramirez R.
Conference Start Date19/09/2013
PublisherIOS Press
Conference LocationPortugal, Volamoura
ISBN Number978-1-61499-304-9
KeywordsAuditory P300, Brain-Computer Interface, EEG, Emotiv
AbstractBrain Computer Interfaces (BCIs) might be the only communication resort for patients with Locked In Syndrome (LIS). Auditory-P300-based interfaces provide an communication alternative to such patients. In this study we evaluate in an on-line setting the Emotiv’s Epoc performance for capturing auditory P300s. Five healthy subjects (3 male, 2 female) participated in an on-line multi-class auditory oddball paradigm. The stimuli set consisted of six musical instruments sounds, different in pitch and stereo spatialization. Two different conditions of 300 ms and 175 ms Inter Stimuli Interval (ISI) were tested. In each condition, the training data consisted of 10 sub-trial recordings, each sub-trial consisting of 25 repetitions in the 175 ms condition and of 15 repetitions in the 300 ms condition. At the beginning of each sub-trial a target sound was presented for the subjects to focus on. Each repetition consisted of a randomized sequence of 6 stimuli appearing once each. After training a spatial filter using xDawn unsupervised algorithm and a linear discriminant analysis (LDA) classifier on a window from 250 ms to 750 ms after the stimuli presentation, the average on-line performance was 96% in the 175 ms condition and 86% in the 300 ms condition. After considering the minimum number of repetitions in order to achieve 70% on-line accuracy, the average ITR is found to be 13.21 bits/min in the 175 ms ISI condition.