| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 930099 | International Journal of Psychophysiology | 2014 | 8 Pages |
•A new mobile EEG system allows recording EEG in daily life.•Auditory BCI feasible in natural environments•Reliable P300 decoding during walking•Differences between walking and seated conditions in brain activity
In a previous study we presented a low-cost, small, and wireless 14-channel EEG system suitable for field recordings (Debener et al., 2012, psychophysiology). In the present follow-up study we investigated whether a single-trial P300 response can be reliably measured with this system, while subjects freely walk outdoors. Twenty healthy participants performed a three-class auditory oddball task, which included rare target and non-target distractor stimuli presented with equal probabilities of 16%. Data were recorded in a seated (control condition) and in a walking condition, both of which were realized outdoors. A significantly larger P300 event-related potential amplitude was evident for targets compared to distractors (p < .001), but no significant interaction with recording condition emerged. P300 single-trial analysis was performed with regularized stepwise linear discriminant analysis and revealed above chance-level classification accuracies for most participants (19 out of 20 for the seated, 16 out of 20 for the walking condition), with mean classification accuracies of 71% (seated) and 64% (walking). Moreover, the resulting information transfer rates for the seated and walking conditions were comparable to a recently published laboratory auditory brain–computer interface (BCI) study. This leads us to conclude that a truly mobile auditory BCI system is feasible.
