@article{EidelKuebler2020,
  author    = {Eidel, Matthias and K{\"u}bler, Andrea},
  title     = {Wheelchair Control in a Virtual Environment by Healthy Participants Using a P300-BCI Based on Tactile Stimulation: Training Effects and Usability},
  series = {Frontiers in Human Neuroscience},
  volume    = {14},
  journal   = {Frontiers in Human Neuroscience},
  issn      = {1662-5161},
  doi       = {10.3389/fnhum.2020.00265},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-207775},
  year      = {2020},
  abstract  = {Tactile stimulation is less frequently used than visual for brain-computer interface (BCI) control, partly because of limitations in speed and accuracy. Non-visual BCI paradigms, however, may be required for patients who struggle with vision dependent BCIs because of a loss of gaze control. With the present study, we attempted to replicate earlier results by Herweg et al. (2016), with several minor adjustments and a focus on training effects and usability. We invited 16 healthy participants and trained them with a 4-class tactile P300-based BCI in five sessions. Their main task was to navigate a virtual wheelchair through a 3D apartment using the BCI. We found significant training effects on information transfer rate (ITR), which increased from a mean of 3.10-9.50 bits/min. Further, both online and offline accuracies significantly increased with training from 65\% to 86\% and 70\% to 95\%, respectively. We found only a descriptive increase of P300 amplitudes at Fz and Cz with training. Furthermore, we report subjective data from questionnaires, which indicated a relatively high workload and moderate to high satisfaction. Although our participants have not achieved the same high performance as in the Herweg et al. (2016) study, we provide evidence for training effects on performance with a tactile BCI and confirm the feasibility of the paradigm.},
  language  = {en}
}
@phdthesis{Herweg2016,
  author    = {Herweg, Andreas},
  title     = {Beyond the state of the art, towards intuitive and reliable non-visual Brain-Computer-Interfacing},
  url       = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133447},
  school      = {Universit{\"a}t W{\"u}rzburg},
  year      = {2016},
  abstract  = {For the present work three main goals were formulated: goal 1 To design a tactile BCI used for mobility which is intuitive (G1.1), reliable and fast while being usable by participants aged 50 years and above. goal 2 To design an auditory BCI used for communication which is intuitive and reliable. goal 3 To examine the effects of training on tactile and auditory BCI performance. Three studies were performed to achieve these goals. In the first study nine participants aged above 50 years performed a five-session training after which eight participants were able to navigate a virtual wheelchair with mean accuracy above 95\% and an ITR above 20 bits / min. In the second study 15 participants, four of them endusers with motor-impairment, were able to communicate meaningful with high accuracies using an auditory BCI. In the third study nine healthy and nine visually impaired participants (regarded as sensory experts for non-visual perception) performed tactile, auditory and visual (for healthy participants only) copy tasks. Participants with trained perception significantly outperformed control participants for tactile but not for auditory performance. Tactile performance of sensory experts was on equal levels as the visual performance of control participants. We were able to demonstrate viability of intuitive gazeindependent tactile and auditory BCI. Our tactile BCI performed on levels similar to those of visual BCI, outperforming current tactile BCI protocols. Furthermore, we were able to demonstrate significant beneficial effect of training on tactile BCI performance. Our results demonstrate previously untapped potential for tactile BCI and avenues for future research in the field of gaze-independent BCI.},
  subject      = {Gehirn-Computer-Schnittstelle},
  language  = {en}
}