Figure 1. Default mode network preservation in patients with acute traumatic disorders of consciousness.

Compared to healthy subjects, patients with acute severe traumatic brain injury diagnosed with coma, vegetative state (VS), minimally conscious state without language function (MCS−), and covert consciousness (CMD, cognitive-motor dissociation) had fewer intact default mode network (DMN) properties than did patients diagnosed with minimally conscious state with language function (MCS+) or post-traumatic confusional state (PTCS). Notably, DMN properties were completely absent in Patient 4 (P4), who had a behavioral diagnosis of VS but demonstrated covert consciousness on a functional magnetic resonance imaging (fMRI) motor imagery task. A yellow outline of the brain indicates an intact DMN property, defined by a Z-value (for correlations and anticorrelations) and percent of suprathreshold voxels (for deactivations) that is within the normal 2.5^th-to-97.5^th percentile of the healthy control group median. For example, P5 demonstrated intact DMN correlations while P6 demonstrated intact DMN correlations, anticorrelations, and deactivations. Color bars for correlations and anticorrelations represent Fisher-transformed Z values. The deactivation color bar represents the Z value for voxels surpassing a Z>3.1 and P=0.05 cluster-corrected threshold. All diagnoses are based on behavioral assessment with the Coma Recovery Scale-Revised, with the exception of the CMD diagnoses, which are based upon evidence of covert consciousness as described in Edlow et al., 2017 and Supplementary Materials.

Abbreviations: CMD cognitive motor dissociation, DMN default mode network, fMRI functional magnetic resonance imaging, L left, MCS− minimally conscious state without language function, MCS+ minimally conscious state with language function, P patient, PTCS post-traumatic confusional state, VS vegetative state