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Recovery of consciousness after traumatic coma is associated with increased alpha and reduced delta frequencies on electroencephalogram (EEG). However, the cortical network properties that underlie these changes are unknown. In this prospective longitudinal study, we focused on small-worldness - the ratio of modular clustering to longrange connections within a network - as small-worldness is a known property of cortical networks in conscious humans. We hypothesized that patients who recover consciousness after traumatic coma show an increase in cortical network small-worldness, and that this correlates with improvement on the Coma Recovery Scale-Revised (CRS-R) score at follow-up. We enrolled 7 patients with traumatic coma (3F; mean age 24 ± 4 years) admitted to the intensive care unit. Patients underwent EEG and CRS-R evaluation at 9 ± 5 days post-injury and follow-up EEG/CRS-R at median day 235 [range 174-656]. For each time point, we calculated maximal cross-correlation between all electrode pairs for each second during five minutes of rest and averaged the resulting networks in order to measure clustering coefficient C, characteristic path length L, and small-worldness (SW = C/L). We used a Wilcoxon signed-rank test to compare network properties between acute and follow-up EEG and a Spearman test to estimate correlations between longitudinal changes in network small-worldness and CRS-R score. Small-worldness significantly increased between acute and follow-up EEG (p = 0.03). Both network properties that comprise small-worldness (C and L) also increased significantly (p = 0.02 and p = 0.03, respectively). At follow-up, all subjects attained a maximum score of 23 on the CRS-R (mean acute-to-chronic increase in CRS-R = 11 ± 10). We did not observe a correlation between longitudinal changes in network measures and CRS-R improvement. Our results suggest that increased cortical small-worldness is associated with recovery of consciousness after traumatic coma. Based on these results, EEG-based network measures may provide quantitative biomarkers of cortical activity, and hence recovery of consciousness, after traumatic coma. [ABSTRACT FROM AUTHOR]