AUTHOR=Charland-Verville Vanessa , Lesenfants Damien , Sela Lee , Noirhomme Quentin , Ziegler Erik , Chatelle Camille , Plotkin Anton , Sobel Noam , Laureys Steven 

TITLE=Detection of response to command using voluntary control of breathing in disorders of consciousness

JOURNAL=Frontiers in Human Neuroscience

VOLUME=8

YEAR=2014

URL=https://www.frontiersin.org/journals/human-neuroscience/articles/10.3389/fnhum.2014.01020

DOI=10.3389/fnhum.2014.01020

ISSN=1662-5161

ABSTRACT=<p><bold>Background</bold>: Detecting signs of consciousness in patients in a vegetative state/unresponsive wakefulness syndrome (UWS/VS) or minimally conscious state (MCS) is known to be very challenging. Plotkin et al. (<xref ref-type="bibr" rid="B21">2010</xref>) recently showed the possibility of using a breathing-controlled communication device in patients with locked in syndrome. We here aim to test a breathing-based “sniff controller” that could be used as an alternative diagnostic tool to evaluate response to command in severely brain damaged patients with chronic disorders of consciousness (DOC).</p><p><bold>Methods</bold>: Twenty-five DOC patients were included. Patients’ resting breathing-amplitude was measured during a 5 min resting condition. Next, they were instructed to end the presentation of a music sequence by sniffing vigorously. An automated detection of changes in breathing amplitude (i.e., &gt;1.5 SD of resting) ended the music and hence provided positive feedback to the patient.</p><p><bold>Results</bold>: None of the 11 UWS/VS patients showed a sniff-based response to command. One out of 14 patients with MCS was able to willfully modulate his breathing pattern to answer the command on 16/19 trials (accuracy 84%). Interestingly, this patient failed to show any other motor response to command.</p><p><bold>Discussion</bold>: We here illustrate the possible interest of using breathing-dependent response to command in the detection of residual cognition in patients with DOC after severe brain injury.</p>