Title
A tactile P300 BCI and the optimal number of tactors: Effects of target probability and discriminability
Author
Brouwer, A.M.
van Erp, J.B.F.
TNO Defensie en Veiligheid
Publication year
2008
Abstract
For P300 based BCIs, tactile stimuli are potentially more suitable than visual or auditory ones, since the do not occupy the visual or auditory channel and they can be delivered to the user without being noticed by others. In this study, we investigate whether a BCI controlled by EEG responses to vibro-tactile stimuli around the waist is feasible. In addition, we explore the effect of varying the number of (equally spaced) tactors: whereas a large number of tactors is expected to enhance the P300 since the target will be more seldom, it could negatively affect the P300 since the shorter distance between the tactors will make it more difficult to discriminate between targets and distracters. Subjects were asked to attend to the vibrations of a (varying) target tactor, embedded within distracters. The number of tactors could be two, four or six. We demonstrated a functioning tactile P300 BCI. Although the P300 in the condition with two tactors (where target and distracter were equally often presented) was smaller compared to the other conditions, we did not find a difference in SWLDA classification performance between the different numbers of tactors.
In een vervolg op ons voorgaande werk over de P300 (een piek in het EEG die optreedt na het presenteren van een doelstimulus) in respons op tactiele stimuli gaan we nu verder in op de toepassing van dit signaal voor BMIs. We demonstreren een BMI die werkt op het richten van aandacht op tactiele stimuli rond het middel. Verder laten we zien dat het aantal gebruikte tactors (twee, vier of zes) de amplitude van de P300 beïnvloedt. Het aantal tactors heeft echter geen effect op hoe goed de stimuli geclassificeerd worden in doelstimulus of niet door een SWLDA.
Subject
Perception
Tactile displays
To reference this document use:
http://resolver.tudelft.nl/uuid:c646de8d-9141-4a6b-990e-2ac9b66a2d23
TNO identifier
22162
Source
4th international brain-computer interface workshop 30 april 2008
Document type
conference paper