The difficulties of behavioral evaluation of prolonged disorders of consciousness (DOC) motivate the development of brain-based diagnostic approaches. The perturbational complexity index (PCI), which measures the complexity of electroencephalographic (EEG) responses to transcranial magnetic stimulation (TMS), showed a remarkable sensitivity in detecting minimal signs of consciousness in previous studies. Here, we tested the reliability of PCI in an independently collected sample of 24 severely brain-injured patients, including 11 unresponsive wakefulness syndrome (UWS), 12 minimally conscious state (MCS) patients, and 1 emergence from MCS patient. We found that the individual maximum PCI value across stimulation sites fell within the consciousness range (i.e., was higher than PCI*, which is an empirical cutoff previously validated on a benchmark population) in 11 MCS patients, yielding a sensitivity of 92% that surpassed qualitative evaluation of resting EEG. Most UWS patients (n = 7, 64%) showed a slow and stereotypical TMS-EEG response, associated with low-complexity PCI values (i.e., ≤PCI*). Four UWS patients (36%) provided high-complexity PCI values, which might suggest a covert capacity for consciousness. In conclusion, this study successfully replicated the performance of PCI in discriminating between UWS and MCS patients, further motivating the application of TMS-EEG in the workflow of DOC evaluation.

Article: Transcranial and spinal cord magnetic stimulation in treatment of spasticity: a literature review and meta-analysis - European Journal of Physical and Rehabilitation Medicine 2018 February;54(1):75-84 - Minerva Medica - Journals

Background: Navigated repetitive transcranial magnetic stimulation (rTMS) is a promising tool for neuromodulation. In previous studies it has been shown that the activity of the default mode network (DMN) areas, particularly of its key region—the angular gyrus—is positively correlated with the level of consciousness. Our study aimed to explore the effect of rTMS of the angular gyrus as a new approach for disorders of consciousness (DOC) treatment; Methods: A 10-session 2-week high-frequency rTMS protocol was delivered over the left angular gyrus in 38 DOC patients with repeated neurobehavioral assessments obtained at baseline and in 2 days after the stimulation course was complete; Results: 20 Hz-rTMS over left angular gyrus improved the coma recovery scale revised (CRS-R) total score in minimally conscious state (MCS) patients. We observed no effects in vegetative state (VS) patients; and Conclusions: The left angular gyrus is likely to be effective target for rTMS in patients with present signs of consciousness.

Purpose: The purpose of this study was to test the effects of navigated repetitive transcranial magnetic stimulation, delivered in different modes, on motor impairments and functional limitations after stroke. Methods: The study sample included 42 patients (58.5 ± 10.7 years; 26 males) who experienced a single unilateral stroke (1–12 months previously) in the area of the middle cerebral artery. Patients completed a course of conventional rehabilitation, together with 10 sessions of navigated repetitive transcranial magnetic stimulation or sham stimulation. Stimulation was scheduled five times a week over two consecutive weeks in an inpatient clinical setting. Patients were randomly assigned to one of four groups and received sham stimulation (n = 10), low-frequency (1-Hz) stimulation of the nonaffected hemisphere (n = 11), high-frequency (10-Hz) stimulation of the affected hemisphere (n = 13), or sequential combination of low- and high-frequency stimulations (n = 8). Participants were evaluated before and after stimulation with clinical tests, including the arm and hand section of the Fugl–Meyer Assessment Scale, modified Ashworth Scale of Muscle Spasticity, and Barthel Index of Activities of Daily Living. Results: Participants in the three groups receiving navigated repetitive transcranial magnetic stimulation showed improvements in arm and hand functions on the Fugl–Meyer Stroke Assessment Scale. Ashworth Scale of Muscle Spasticity and Barthel Index scores were significantly reduced in groups receiving low- or high-frequency stimulation alone. Conclusions: Including navigated repetitive transcranial magnetic stimulation in a conventional rehabilitation program positively influenced motor and functional recovery in study participants, demonstrating the clinical potential of the method. The results of this study will be used for designing a large-scale clinical trial.