TY  - JOUR
A1  - Lugo, Zulay R.
A1  - Quitadamo, Lucia R.
A1  - Bianchi, Luigi
A1  - Pellas, Fréderic
A1  - Veser, Sandra
A1  - Lesenfants, Damien
A1  - Real, Ruben G. L.
A1  - Herbert, Cornelia
A1  - Guger, Christoph
A1  - Kotchoubey, Boris
A1  - Mattia, Donatella
A1  - Kübler, Andrea
A1  - Laureys, Steven
A1  - Noirhomme, Quentin
T1  - Cognitive Processing in Non-Communicative Patients: What Can Event-Related Potentials Tell Us?
JF  - Frontiers in Human Neuroscience
N2  - Event-related potentials (ERP) have been proposed to improve the differential diagnosis of non-responsive patients. We investigated the potential of the P300 as a reliable marker of conscious processing in patients with locked-in syndrome (LIS). Eleven chronic LIS patients and 10 healthy subjects (HS) listened to a complex-tone auditory oddball paradigm, first in a passive condition (listen to the sounds) and then in an active condition (counting the deviant tones). Seven out of nine HS displayed a P300 waveform in the passive condition and all in the active condition. HS showed statistically significant changes in peak and area amplitude between conditions. Three out of seven LIS patients showed the P3 waveform in the passive condition and five of seven in the active condition. No changes in peak amplitude and only a significant difference at one electrode in area amplitude were observed in this group between conditions. We conclude that, in spite of keeping full consciousness and intact or nearly intact cortical functions, compared to HS, LIS patients present less reliable results when testing with ERP, specifically in the passive condition. We thus strongly recommend applying ERP paradigms in an active condition when evaluating consciousness in non-responsive patients.
KW  - P300
KW  - event-related potentials
KW  - locked-in syndrome
KW  - vegetative state
KW  - unresponsive wakefulness syndrome
KW  - minimally conscious state
Y1  - 2016
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-165165
VL  - 10
IS  - 569
ER  - 
TY  - JOUR
A1  - Kübler, Andrea
A1  - Holz, Elisa M.
A1  - Riccio, Angela
A1  - Zickler, Claudia
A1  - Kaufmann, Tobias
A1  - Kleih, Sonja C.
A1  - Staiger-Sälzer, Pit
A1  - Desideri, Lorenzo
A1  - Hoogerwerf, Evert-Jan
A1  - Mattia, Donatella
T1  - The User-Centered Design as Novel Perspective for Evaluating the Usability of BCI-Controlled Applications
N2  - Albeit research on brain-computer interfaces (BCI) for controlling applications has expanded tremendously, we still face a translational gap when bringing BCI to end-users. To bridge this gap, we adapted the user-centered design (UCD) to BCI research and development which implies a shift from focusing on single aspects, such as accuracy and information transfer rate (ITR), to a more holistic user experience. The UCD implements an iterative process between end-users and developers based on a valid evaluation procedure. Within the UCD framework usability of a device can be defined with regard to its effectiveness, efficiency, and satisfaction. We operationalized these aspects to evaluate BCI-controlled applications. Effectiveness was regarded equivalent to accuracy of selections and efficiency to the amount of information transferred per time unit and the effort invested (workload). Satisfaction was assessed with questionnaires and visual-analogue scales. These metrics have been successfully applied to several BCI-controlled applications for communication and entertainment, which were evaluated by end-users with severe motor impairment. Results of four studies, involving a total of N = 19 end-users revealed: effectiveness was moderate to high; efficiency in terms of ITR was low to high and workload low to medium; depending on the match between user and technology, and type of application satisfaction was moderate to high. The here suggested evaluation metrics within the framework of the UCD proved to be an applicable and informative approach to evaluate BCI controlled applications, and end-users with severe impairment and in the locked-in state were able to participate in this process.
KW  - computer software
KW  - event related potentials
KW  - games
KW  - head
KW  - head injury
KW  - man-computer interface
KW  - prototypes
KW  - speech
Y1  - 2014
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-111051
ER  -