Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2016 Nov 14:10:569.
doi: 10.3389/fnhum.2016.00569. eCollection 2016.

Cognitive Processing in Non-Communicative Patients: What Can Event-Related Potentials Tell Us?

Zulay R Lugo  1 , Lucia R Quitadamo  2 , Luigi Bianchi  3 , Fréderic Pellas  4 , Sandra Veser  5 , Damien Lesenfants  6 , Ruben G L Real  7 , Cornelia Herbert  8 , Christoph Guger  9 , Boris Kotchoubey  5 , Donatella Mattia  10 , Andrea Kübler  7 , Steven Laureys  6 , Quentin Noirhomme  11
Affiliations

Cognitive Processing in Non-Communicative Patients: What Can Event-Related Potentials Tell Us?

Zulay R Lugo et al. Front Hum Neurosci. .

Abstract

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.

Keywords: P300; event-related potentials; locked-in syndrome; minimally conscious state; unresponsive wakefulness syndrome; vegetative state.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Grand averaged P300 waveforms for each group at each task condition. (A) Passive condition, (B) active condition. Blue waveform is the average of the standard stimuli. Red waveform is the average of deviant stimuli.
Figure 2
Figure 2
Individuals P300 waveforms in the patients with locked-in syndrome (LIS) at each task condition. (A) Passive condition, (B) active condition. Blue waveform is the average of the standard stimuli. Red waveform is the average of deviant stimuli.
See this image and copyright information in PMC

References

    1. American Congress of Rehabilitation Medicine . (1995). Recommendations for use of uniform nomenclature pertinent to patients with severe alterations in consciousness. Arch. Phys. Med. Rehabil. 76, 205–209. 10.1016/s0003-9993(95)80031-x - DOI - PubMed
    1. Andrews K., Murphy L., Munday R., Littlewood C. (1996). Misdiagnosis of the vegetative state: retrospective study in a rehabilitation unit. BMJ 313, 13–16. 10.1136/bmj.313.7048.13 - DOI - PMC - PubMed
    1. Bauer G., Gerstenbrand F., Rumpl E. (1979). Varieties of the locked-in syndrome. J. Neurol. 221, 77–91. 10.1007/bf00313105 - DOI - PubMed
    1. Benjamini Y., Hochberg Y. (1995). Controlling the false discovery rate: a practical and powerful approach to multiple testing. J. R. Stat. Soc. Ser. B 57, 289–300.
    1. Bianchi L., Quitadamo L. R., Abbafati M., Marciani M. G., Saggio G. (2009). “Introducing NPXlab 2010: a tool for the analysis and optimization of P300 based brain-computer interfaces,” in Proceeding of the 2nd International Symposium on Applied Sciences in Biomedical and Communication Technologies, ISABEL. (Bratislava, Slovakia).

LinkOut - more resources