{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T12:03:27Z","timestamp":1789387407919,"version":"build-2803163510"},"reference-count":47,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T00:00:00Z","timestamp":1789344000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurosci."],"abstract":"<jats:p>\n                    Transcranial direct current stimulation (tDCS) is a promising intervention for chronic disorders of consciousness (DoC), yet therapeutic responsiveness varies substantially across patients and does not conform to diagnostic boundaries. Contemporary theories of consciousness implicate the posterior parietal cortex as a critical node for conscious processing, but the electrophysiological mechanisms engaged by posterior parietal stimulation remain poorly characterized. High-definition tDCS (HD-tDCS) was applied over Pz in 42 patients with chronic DoC, who were stratified as responders (R+,\n                    <jats:italic>n<\/jats:italic>\n                    =\u202f32) or non-responders (R\u2212,\n                    <jats:italic>n<\/jats:italic>\n                    =\u202f10) according to the emergence of new behavioral signs on the Coma Recovery Scale\u2013Revised. Resting-state electroencephalography (EEG) was analyzed using spectral parameterization (FOOOF), band-limited estimates within two frequency windows informed by the ABCD framework (5\u20139\u202fHz and 20\u201335\u202fHz), recurrence quantification analysis (RQA), Lempel\u2013Ziv complexity (LZc), and normalized spatial complexity (NSC). In R+ only, the aperiodic exponent decreased at four centro-parietal electrodes, power in the 20\u201335\u202fHz window increased at nine electrodes, RQA metrics decreased across 13\u201318 electrodes, LZc increased at 11 electrodes, and NSC in the 20\u201335\u202fHz window increased significantly (\n                    <jats:italic>p<\/jats:italic>\n                    =\u202f0.0222). No corresponding changes were detected in R\u2212. Relief-based feature selection identified the aperiodic exponent and the 20\u201335\u202fHz NSC feature from eight candidate biomarkers for training a Bayesian-optimized support vector machine. SHapley Additive exPlanations indicated comparable contributions from both features. These findings identify responder-specific changes in periodic and aperiodic spectral parameters and in nonlinear EEG descriptors following Pz-targeted HD-tDCS. They are consistent with modulation of cortical state and large-scale dynamics, but do not by themselves demonstrate excitation\u2013inhibition rebalancing or thalamocortical loop reinforcement, and the single-arm design without sham stimulation precludes attribution of the observed changes specifically to HD-tDCS.\n                  <\/jats:p>","DOI":"10.3389\/fnins.2026.1925503","type":"journal-article","created":{"date-parts":[[2026,9,14]],"date-time":"2026-09-14T11:10:45Z","timestamp":1789384245000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["Multidimensional EEG mechanisms and explainable prediction of responsiveness to posterior parietal HD-tDCS in chronic disorders of consciousness"],"prefix":"10.3389","volume":"20","author":[{"given":"Xiangyun","family":"Zou","sequence":"first","affiliation":[{"name":"Department of Pediatrics, Qilu Hospital of Shandong University (Qingdao)","place":["Qingdao, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bin","family":"Jiang","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Qilu Hospital of Shandong University (Qingdao)","place":["Qingdao, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chunyun","family":"Zhang","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Qilu Hospital of Shandong University (Qingdao)","place":["Qingdao, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,9,14]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"1409","DOI":"10.1080\/02699052.2019.1644376","article-title":"Diagnostic accuracy of the CRS-R index in patients with disorders of consciousness","volume":"33","author":"Annen","year":"2019","journal-title":"Brain Inj."},{"key":"ref2","doi-asserted-by":"publisher","first-page":"169","DOI":"10.5334\/pb.1381","article-title":"Disorders of consciousness, language and communication following severe brain injury","volume":"65","author":"Aubinet","year":"2025","journal-title":"Psychol Belg"},{"key":"ref3","doi-asserted-by":"publisher","first-page":"9603","DOI":"10.1523\/JNEUROSCI.3218-16.2017","article-title":"Are the neural correlates of consciousness in the front or in the Back of the cerebral cortex? Clinical and neuroimaging evidence","volume":"37","author":"Boly","year":"2017","journal-title":"J. Neurosci."},{"key":"ref4","doi-asserted-by":"publisher","first-page":"198ra105","DOI":"10.1126\/scitranslmed.3006294","article-title":"A theoretically based index of consciousness independent of sensory processing and behavior","volume":"5","author":"Casali","year":"2013","journal-title":"Sci. Transl. Med."},{"key":"ref5","doi-asserted-by":"publisher","first-page":"231","DOI":"10.1016\/j.clinph.2018.10.018","article-title":"Behavioural and electrophysiological effects of tDCS to prefrontal cortex in patients with disorders of consciousness","volume":"130","author":"Cavinato","year":"2019","journal-title":"Clin. Neurophysiol."},{"key":"ref6","doi-asserted-by":"publisher","first-page":"2736","DOI":"10.1016\/j.clinph.2020.07.015","article-title":"Clinical and advanced neurophysiology in the prognostic and diagnostic evaluation of disorders of consciousness: review of an IFCN-endorsed expert group","volume":"131","author":"Comanducci","year":"2020","journal-title":"Clin. Neurophysiol."},{"key":"ref7","doi-asserted-by":"publisher","first-page":"9","DOI":"10.1016\/j.jneumeth.2003.10.009","article-title":"EEGLAB: an open source toolbox for analysis of single-trial EEG dynamics including independent component analysis","volume":"134","author":"Delorme","year":"2004","journal-title":"J. Neurosci. Methods"},{"key":"ref8","doi-asserted-by":"publisher","first-page":"eaat7603","DOI":"10.1126\/sciadv.aat7603","article-title":"Human consciousness is supported by dynamic complex patterns of brain signal coordination","volume":"5","author":"Demertzi","year":"2019","journal-title":"Sci. Adv."},{"key":"ref9","doi-asserted-by":"publisher","first-page":"1655","DOI":"10.1038\/s41593-020-00744-x","article-title":"Parameterizing neural power spectra into periodic and aperiodic components","volume":"23","author":"Donoghue","year":"2020","journal-title":"Nat. Neurosci."},{"key":"ref10","doi-asserted-by":"publisher","first-page":"138","DOI":"10.1007\/s10548-023-01024-0","article-title":"Distinct spectral profiles of awake resting EEG in disorders of consciousness: the role of frequency and topography of oscillations","volume":"37","author":"Dr\u0105\u017cyk","year":"2024","journal-title":"Brain Topogr."},{"key":"ref11","doi-asserted-by":"publisher","first-page":"135","DOI":"10.1038\/s41582-020-00428-x","article-title":"Recovery from disorders of consciousness: mechanisms, prognosis and emerging therapies","volume":"17","author":"Edlow","year":"2021","journal-title":"Nat. Rev. Neurol."},{"key":"ref12","doi-asserted-by":"publisher","first-page":"119","DOI":"10.1002\/acn3.385","article-title":"Dynamic regimes of neocortical activity linked to corticothalamic integrity correlate with outcomes in acute anoxic brain injury after cardiac arrest","volume":"4","author":"Forgacs","year":"2017","journal-title":"Ann. Clin. Transl. Neurol."},{"key":"ref13","doi-asserted-by":"publisher","first-page":"70","DOI":"10.1016\/j.neuroimage.2017.06.078","article-title":"Inferring synaptic excitation\/inhibition balance from field potentials","volume":"158","author":"Gao","year":"2017","journal-title":"NeuroImage"},{"key":"ref14","doi-asserted-by":"publisher","first-page":"991","DOI":"10.1007\/s12021-022-09581-8","article-title":"Separating neural oscillations from aperiodic 1\/f activity: challenges and recommendations","volume":"20","author":"Gerster","year":"2022","journal-title":"Neuroinformatics"},{"key":"ref15","doi-asserted-by":"publisher","first-page":"99","DOI":"10.1038\/nrneurol.2013.279","article-title":"Disorders of consciousness after acquired brain injury: the state of the science","volume":"10","author":"Giacino","year":"2014","journal-title":"Nat. Rev. Neurol."},{"key":"ref16","doi-asserted-by":"publisher","first-page":"27218","DOI":"10.1038\/s41598-025-12462-0","article-title":"Modulation of consciousness in disorders of consciousness by HD-tDCS targeting frontal and posterior cortical regions","volume":"15","author":"Guo","year":"2025","journal-title":"Sci. Rep."},{"key":"ref17","doi-asserted-by":"publisher","first-page":"889023","DOI":"10.3389\/fnhum.2022.889023","article-title":"High-definition transcranial direct current stimulation of the dorsolateral prefrontal cortex modulates the electroencephalography rhythmic activity of parietal occipital lobe in patients with chronic disorders of consciousness","volume":"16","author":"Han","year":"2022","journal-title":"Front. Hum. Neurosci."},{"key":"ref18","doi-asserted-by":"publisher","first-page":"4323","DOI":"10.1038\/s41598-020-61180-2","article-title":"Combined behavioral and electrophysiological evidence for a direct cortical effect of prefrontal tDCS on disorders of consciousness","volume":"10","author":"Hermann","year":"2020","journal-title":"Sci. Rep."},{"key":"ref19","doi-asserted-by":"publisher","first-page":"7912","DOI":"10.1038\/s41598-018-26329-0","article-title":"Normalized spatial complexity analysis of neural signals","volume":"8","author":"Jia","year":"2018","journal-title":"Sci. Rep."},{"key":"ref20","doi-asserted-by":"publisher","first-page":"187","DOI":"10.3390\/e22020187","article-title":"Coded permutation entropy: a measure for dynamical changes based on the secondary partitioning of amplitude information","volume":"22","author":"Kang","year":"2020","journal-title":"Entropy"},{"key":"ref21","doi-asserted-by":"publisher","first-page":"644","DOI":"10.1016\/j.brs.2012.09.010","article-title":"Comparing cortical plasticity induced by conventional and high-definition 4 \u00d7 1 ring tDCS: a neurophysiological study","volume":"6","author":"Kuo","year":"2013","journal-title":"Brain Stimul."},{"key":"ref22","doi-asserted-by":"publisher","first-page":"75","DOI":"10.1109\/TIT.1976.1055501","article-title":"On the complexity of finite sequences","volume":"22","author":"Lempel","year":"1976","journal-title":"IEEE Trans. Inf. Theory"},{"key":"ref23","doi-asserted-by":"publisher","first-page":"140","DOI":"10.1186\/s12883-023-03167-w","article-title":"EEG complexity correlates with residual consciousness level of disorders of consciousness","volume":"23","author":"Liu","year":"2023","journal-title":"BMC Neurol."},{"key":"ref24","first-page":"4765","article-title":"A unified approach to interpreting model predictions","volume":"30","author":"Lundberg","year":"2017","journal-title":"Adv. Neural. Infor. Proces. Syst."},{"key":"ref25","doi-asserted-by":"publisher","first-page":"926","DOI":"10.3389\/fpsyg.2016.00926","article-title":"Integrated information and state differentiation","volume":"7","author":"Marshall","year":"2016","journal-title":"Front. Psychol."},{"key":"ref26","doi-asserted-by":"publisher","first-page":"102426","DOI":"10.1016\/j.nicl.2020.102426","article-title":"Behavioral and electrophysiological effects of network-based frontoparietal tDCS in patients with severe brain injury: a randomized controlled trial","volume":"28","author":"Martens","year":"2020","journal-title":"Neuroimage Clin"},{"key":"ref27","doi-asserted-by":"publisher","first-page":"237","DOI":"10.1016\/j.physrep.2006.11.001","article-title":"Recurrence plots for the analysis of complex systems","volume":"438","author":"Marwan","year":"2007","journal-title":"Phys. Rep."},{"key":"ref28","doi-asserted-by":"publisher","first-page":"776","DOI":"10.1016\/j.neuron.2020.01.026","article-title":"Conscious processing and the global neuronal workspace hypothesis","volume":"105","author":"Mashour","year":"2020","journal-title":"Neuron"},{"key":"ref29","doi-asserted-by":"publisher","first-page":"bhad482","DOI":"10.1093\/cercor\/bhad482","article-title":"Test-retest reliability of spectral parameterization by 1\/f characterization using SpecParam","volume":"34","author":"McKeown","year":"2024","journal-title":"Cereb. Cortex"},{"key":"ref30","doi-asserted-by":"publisher","first-page":"62","DOI":"10.3389\/fnsys.2020.00062","article-title":"Decreased evoked slow-activity after tDCS in disorders of consciousness","volume":"14","author":"Mensen","year":"2020","journal-title":"Front. Syst. Neurosci."},{"key":"ref31","doi-asserted-by":"publisher","first-page":"156869","DOI":"10.1155\/2011\/156869","article-title":"FieldTrip: open source software for advanced analysis of MEG, EEG, and invasive electrophysiological data","volume":"2011","author":"Oostenveld","year":"2011","journal-title":"Comput. Intell. Neurosci."},{"key":"ref32","doi-asserted-by":"publisher","first-page":"niab023","DOI":"10.1093\/nc\/niab023","article-title":"Consciousness and complexity: a consilience of evidence","volume":"2021","author":"Sarasso","year":"2021","journal-title":"Neurosci. Conscious."},{"key":"ref33","doi-asserted-by":"publisher","first-page":"e0133532","DOI":"10.1371\/journal.pone.0133532","article-title":"Complexity of multi-dimensional spontaneous EEG decreases during Propofol induced general Anaesthesia","volume":"10","author":"Schartner","year":"2015","journal-title":"PLoS One"},{"key":"ref34","doi-asserted-by":"crossref","first-page":"195","DOI":"10.1007\/978-3-319-21425-2_15","volume-title":"Brain Function and Responsiveness in Disorders of Consciousness","author":"Schiff","year":"2016"},{"key":"ref35","doi-asserted-by":"publisher","first-page":"104161","DOI":"10.1016\/j.lpm.2022.104161","article-title":"Mesocircuit mechanisms in the diagnosis and treatment of disorders of consciousness","volume":"52","author":"Schiff","year":"2023","journal-title":"Presse Med."},{"key":"ref36","doi-asserted-by":"publisher","first-page":"439","DOI":"10.1038\/s41583-022-00587-4","article-title":"Theories of consciousness","volume":"23","author":"Seth","year":"2022","journal-title":"Nat. Rev. Neurosci."},{"key":"ref37","doi-asserted-by":"publisher","first-page":"89","DOI":"10.1080\/17588928.2020.1838467","article-title":"Predictive processing as an empirical theory for consciousness science","volume":"12","author":"Seth","year":"2021","journal-title":"Cogn. Neurosci."},{"key":"ref38","doi-asserted-by":"publisher","first-page":"1838064","DOI":"10.3389\/fnhum.2026.1838064","article-title":"The current status of foundation models in decoding inner speech from non-invasive brain signals: a mini review","volume":"20","author":"S\u00fcmer-Arpak","year":"2026","journal-title":"Front. Hum. Neurosci."},{"key":"ref39","doi-asserted-by":"publisher","first-page":"450","DOI":"10.1038\/nrn.2016.44","article-title":"Integrated information theory: from consciousness to its physical substrate","volume":"17","author":"Tononi","year":"2016","journal-title":"Nat. Rev. Neurosci."},{"key":"ref40","doi-asserted-by":"publisher","first-page":"8098","DOI":"10.1109\/JBHI.2025.3635229","article-title":"N-cylindrical symbolic response, a standalone and synergistic biomarker for epilepsy diagnosis on EEG modality","volume":"30","author":"Varun","year":"2026","journal-title":"IEEE J. Biomed. Health Inform."},{"key":"ref41","doi-asserted-by":"publisher","first-page":"381","DOI":"10.3389\/fnins.2020.00381","article-title":"Combined behavioral and mismatch negativity evidence for the effects of long-lasting high-definition tDCS in disorders of consciousness: a pilot study","volume":"14","author":"Wang","year":"2020","journal-title":"Front. Neurosci."},{"key":"ref42","doi-asserted-by":"publisher","first-page":"509","DOI":"10.1109\/TNSRE.2022.3154772","article-title":"Application of fast Perturbational complexity index to the diagnosis and prognosis for disorders of consciousness","volume":"30","author":"Wang","year":"2022","journal-title":"IEEE Trans. Neural Syst. Rehabil. Eng."},{"key":"ref43","doi-asserted-by":"publisher","first-page":"e75020","DOI":"10.2196\/75020","article-title":"Machine learning and Shapley additive explanations value integration for predicting the prognostic of anti-N-methyl-D-aspartate receptor encephalitis: model development and evaluation study","volume":"13","author":"Wang","year":"2025","journal-title":"JMIR Med Inform"},{"key":"ref44","doi-asserted-by":"publisher","first-page":"e1996","DOI":"10.1089\/neu.2023.0567","article-title":"Interpreting change in disorders of consciousness using the Coma Recovery Scale\u2013Revised","volume":"41","author":"Weaver","year":"2024","journal-title":"J Neurotrauma"},{"key":"ref45","doi-asserted-by":"publisher","first-page":"167","DOI":"10.1186\/s12984-024-01455-1","article-title":"Perturbational complexity index in assessing responsiveness to rTMS treatment in patients with disorders of consciousness: a cross-over randomized controlled trial study","volume":"21","author":"Xu","year":"2024","journal-title":"J. Neuroeng. Rehabil."},{"key":"ref46","doi-asserted-by":"publisher","first-page":"197","DOI":"10.1016\/j.neures.2019.09.003","article-title":"Information-theoretic approach to detect directional information flow in EEG signals induced by TMS","volume":"156","author":"Ye","year":"2020","journal-title":"Neurosci. Res."},{"key":"ref47","doi-asserted-by":"publisher","first-page":"903703","DOI":"10.3389\/fnins.2022.903703","article-title":"Multidimensional assessment of electroencephalography in the neuromodulation of disorders of consciousness","volume":"16","author":"Zhang","year":"2022","journal-title":"Front. 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