ИСТИНА

Background. Widespread loss of cerebral connectivity is assumed to underlie the failure of brain mechanisms that support communication and purposeful behaviour following severe brain injury. Recent studies showed preservation of large-scale cerebral networks in minimally conscious state (MCS) patients (Adams, 2000). We present stroke patient who was in MSC after hypertensive thalamic hemorrhage without diffuse cortical damage (Fig.1) with patterns observed on resting-state fMRI and TMS-EEG similar to consciousness state. Case. Patient B., female, 31 y.o. had 18 CRS-R score 1 year after left thalamic hemorrhage with fluctuating consciousness level. She improved gradually with spontaneous eye opening and simple commands following although communication was limited to yes/no answers on voices recognition. We used rs-fMRI to investigate the default mode network (DMN; Vanhaudenhuyse, 2010) residual signal and found out activation in precuneus, bilateral temporo-parietal junctions and medial prefrontal cortex that was similar to healthy controls (Fig.1). TMS-EEG showed high perturbational complexity index (PCI; Casali, 2014) of 0.383 ( > 0.31, which is considered as cutoff level between unconscious and the conscious conditions; Casarotto, 2016), that corresponds to high complexity of TMS cortical response, same as in healthy controls (Fig. 2, 3). Conclusion. By means of novel methods of consciousness detection, based on assessment of cortical activity and cerebral networks, patient appears to be conscious. We hypothesize that isolated dysfunction of thalamo-cortical interactions caused by thalamic damage lead to clinically seen reduced level of consciousness. The study is supported by RSF grant №16-15-00274.