@article{JinAllisonKaufmannetal.2012,
  author    = {Jin, Jing and Allison, Brendan Z. and Kaufmann, Tobias and K{\"u}bler, Andrea and Zhang, Yu and Wang, Xingyu and Cichocki, Andrzej},
  title     = {The Changing Face of P300 BCIs: A Comparison of Stimulus Changes in a P300 BCI Involving Faces, Emotion, and Movement},
  series = {PLoS One},
  volume    = {7},
  journal   = {PLoS One},
  number    = {11},
  doi       = {10.1371/journal.pone.0049688},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-134173},
  pages     = {e49688},
  year      = {2012},
  abstract  = {Background: One of the most common types of brain-computer interfaces (BCIs) is called a P300 BCI, since it relies on the P300 and other event-related potentials (ERPs). In the canonical P300 BCI approach, items on a monitor flash briefly to elicit the necessary ERPs. Very recent work has shown that this approach may yield lower performance than alternate paradigms in which the items do not flash but instead change in other ways, such as moving, changing colour or changing to characters overlaid with faces. Methodology/Principal Findings: The present study sought to extend this research direction by parametrically comparing different ways to change items in a P300 BCI. Healthy subjects used a P300 BCI across six different conditions. Three conditions were similar to our prior work, providing the first direct comparison of characters flashing, moving, and changing to faces. Three new conditions also explored facial motion and emotional expression. The six conditions were compared across objective measures such as classification accuracy and bit rate as well as subjective measures such as perceived difficulty. In line with recent studies, our results indicated that the character flash condition resulted in the lowest accuracy and bit rate. All four face conditions (mean accuracy >91\%) yielded significantly better performance than the flash condition (mean accuracy = 75\%). Conclusions/Significance: Objective results reaffirmed that the face paradigm is superior to the canonical flash approach that has dominated P300 BCIs for over 20 years. The subjective reports indicated that the conditions that yielded better performance were not considered especially burdensome. Therefore, although further work is needed to identify which face paradigm is best, it is clear that the canonical flash approach should be replaced with a face paradigm when aiming at increasing bit rate. However, the face paradigm has to be further explored with practical applications particularly with locked-in patients.},
  language  = {en}
}
@article{KleihHerwegKaufmannetal.2015,
  author    = {Kleih, Sonja C. and Herweg, Andreas and Kaufmann, Tobias and Staiger-S{\"a}lzer, Pit and Gerstner, Natascha and K{\"u}bler, Andrea},
  title     = {The WIN-speller: a new intuitive auditory brain-computer interface spelling application},
  series = {Frontiers in Neuroscience},
  volume    = {9},
  journal   = {Frontiers in Neuroscience},
  doi       = {10.3389/fnins.2015.00346},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-125972},
  pages     = {346},
  year      = {2015},
  abstract  = {The objective of this study was to test the usability of a new auditory Brain-Computer Interface (BCI) application for communication. We introduce a word based, intuitive auditory spelling paradigm the WIN-speller. In the WIN-speller letters are grouped by words, such as the word KLANG representing the letters A, G, K, L, and N. Thereby, the decoding step between perceiving a code and translating it to the stimuli it represents becomes superfluous. We tested 11 healthy volunteers and four end-users with motor impairment in the copy spelling mode. Spelling was successful with an average accuracy of 84\% in the healthy sample. Three of the end-users communicated with average accuracies of 80\% or higher while one user was not able to communicate reliably. Even though further evaluation is required, the WIN-speller represents a potential alternative for BCI based communication in end-users.},
  language  = {en}
}