Brain Metabolism but Not Gray Matter Volume Underlies the Presence of Language Function in the Minimally Conscious State (MCS): MCS+ Versus MCS− Neuroimaging Differences

Background. The minimally conscious state (MCS) is subcategorized into MCS− and MCS+, depending on the absence or presence, respectively, of high-level behavioral responses such as command-following. Objective. We aim to investigate the functional and structural neuroanatomy underlying the presence of these responses in MCS− and MCS+ patients. Methods. In this cross-sectional retrospective study, chronic MCS patients were diagnosed using repeated Coma Recovery Scale–Revised assessments. Fluorodeoxyglucose-positron emission tomography data were acquired on 57 patients (16 MCS−; 41 MCS+) and magnetic resonance imaging with voxel-based morphometry analysis was performed on 66 patients (17 MCS−; 49 MCS+). Brain glucose metabolism and gray matter integrity were compared between patient groups and control groups. A metabolic functional connectivity analysis testing the hypothesis of preserved language network in MCS+ compared with MCS− was also done. Results. Patients in MCS+ presented higher metabolism mainly in the left middle temporal cortex, known to be important for semantic processing, compared with the MCS− group. The left angular gyrus was also functionally disconnected from the left prefrontal cortex in MCS− compared with MCS+ group. No significant differences were found in gray matter volume between patient groups. Conclusions. The clinical subcategorization of MCS is supported by differences in brain metabolism but not in gray matter structure, suggesting that brain function in the language network is the main support for recovery of command-following, intelligible verbalization and/or intentional communication in the MCS. Better characterizing the neural correlates of residual cognitive abilities of MCS patients contributes to reduce their misdiagnosis and to adapt therapeutic approaches.

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Auditory localization should be considered as a sign of minimally conscious state based on multimodal findings

Brain Communications ◽

10.1093/braincomms/fcaa195 ◽

2020 ◽

Vol 2 (2) ◽

Author(s):

Manon Carrière ◽

Helena Cassol ◽

Charlène Aubinet ◽

Rajanikant Panda ◽

Aurore Thibaut ◽

...

Keyword(s):

Brain Function ◽

Brain Metabolism ◽

Survival Rates ◽

Minimally Conscious State ◽

Conscious State ◽

Auditory Localization ◽

Positron Emission ◽

Level Of Consciousness ◽

Minimally Conscious

Abstract Auditory localization (i.e. turning the head and/or the eyes towards an auditory stimulus) is often part of the clinical evaluation of patients recovering from coma. The objective of this study is to determine whether auditory localization could be considered as a new sign of minimally conscious state, using a multimodal approach. The presence of auditory localization and the clinical outcome at 2 years of follow-up were evaluated in 186 patients with severe brain injury, including 64 with unresponsive wakefulness syndrome, 28 in minimally conscious state minus, 71 in minimally conscious state plus and 23 who emerged from the minimally conscious state. Brain metabolism, functional connectivity and graph theory measures were investigated by means of 18F-fluorodeoxyglucose positron emission tomography, functional MRI and high-density electroencephalography in two subgroups of unresponsive patients, with and without auditory localization. These two subgroups were also compared to a subgroup of patients in minimally conscious state minus. Auditory localization was observed in 13% of unresponsive patients, 46% of patients in minimally conscious state minus, 62% of patients in minimally conscious state plus and 78% of patients who emerged from the minimally conscious state. The probability to observe an auditory localization increased along with the level of consciousness, and the presence of auditory localization could predict the level of consciousness. Patients with auditory localization had higher survival rates (at 2-year follow-up) than those without localization. Differences in brain function were found between unresponsive patients with and without auditory localization. Higher connectivity in unresponsive patients with auditory localization was measured between the fronto-parietal network and secondary visual areas, and in the alpha band electroencephalography network. Moreover, patients in minimally conscious state minus significantly differed from unresponsive patients without auditory localization in terms of brain metabolism and alpha network centrality, whereas no difference was found with unresponsive patients who presented auditory localization. Our multimodal findings suggest differences in brain function between unresponsive patients with and without auditory localization, which support our hypothesis that auditory localization should be considered as a new sign of minimally conscious state. Unresponsive patients showing auditory localization should therefore no longer be considered unresponsive but minimally conscious. This would have crucial consequences on these patients’ lives as it would directly impact the therapeutic orientation or end-of-life decisions usually taken based on the diagnosis.

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Poster 21: Criteria for Emergence From the Minimally Conscious State: What About Consistent Command-following?

Archives of Physical Medicine and Rehabilitation ◽

10.1016/j.apmr.2009.08.051 ◽

2009 ◽

Vol 90 (10) ◽

pp. e18

Author(s):

Caroline Schnakers ◽

Joseph Giacino

Keyword(s):

Minimally Conscious State ◽

Conscious State ◽

Minimally Conscious ◽

Command Following

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Prognosis for patients with cognitive motor dissociation identified by brain-computer interface

Brain ◽

10.1093/brain/awaa026 ◽

2020 ◽

Vol 143 (4) ◽

pp. 1177-1189 ◽

Cited By ~ 6

Author(s):

Jiahui Pan ◽

Qiuyou Xie ◽

Pengmin Qin ◽

Yan Chen ◽

Yanbin He ◽

...

Keyword(s):

Patient Group ◽

Brain Computer Interface ◽

Minimally Conscious State ◽

Conscious State ◽

Disorders Of Consciousness ◽

The Other ◽

Computer Interface ◽

Unresponsive Wakefulness Syndrome ◽

Minimally Conscious ◽

Command Following

Abstract Cognitive motor dissociation describes a subset of patients with disorders of consciousness who show neuroimaging evidence of consciousness but no detectable command-following behaviours. Although essential for family counselling, decision-making, and the design of rehabilitation programmes, the prognosis for patients with cognitive motor dissociation remains under-investigated. The current study included 78 patients with disorders of consciousness who showed no detectable command-following behaviours. These patients included 45 patients with unresponsive wakefulness syndrome and 33 patients in a minimally conscious state, as diagnosed using the Coma Recovery Scale-Revised. Each patient underwent an EEG-based brain-computer interface experiment, in which he or she was instructed to perform an item-selection task (i.e. select a photograph or a number from two candidates). Patients who achieved statistically significant brain-computer interface accuracies were identified as cognitive motor dissociation. Two evaluations using the Coma Recovery Scale-Revised, one before the experiment and the other 3 months later, were carried out to measure the patients’ behavioural improvements. Among the 78 patients with disorders of consciousness, our results showed that within the unresponsive wakefulness syndrome patient group, 15 of 18 patients with cognitive motor dissociation (83.33%) regained consciousness, while only five of the other 27 unresponsive wakefulness syndrome patients without significant brain-computer interface accuracies (18.52%) regained consciousness. Furthermore, within the minimally conscious state patient group, 14 of 16 patients with cognitive motor dissociation (87.5%) showed improvements in their Coma Recovery Scale-Revised scores, whereas only four of the other 17 minimally conscious state patients without significant brain-computer interface accuracies (23.53%) had improved Coma Recovery Scale-Revised scores. Our results suggest that patients with cognitive motor dissociation have a better outcome than other patients. Our findings extend current knowledge of the prognosis for patients with cognitive motor dissociation and have important implications for brain-computer interface-based clinical diagnosis and prognosis for patients with disorders of consciousness.

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Association of Plasma Complement System With Brain Structure Deficits in Bipolar and Major Depressive Disorders

10.21203/rs.3.rs-922528/v1 ◽

2021 ◽

Author(s):

Hua Yu ◽

Peiyan Ni ◽

Yang Tian ◽

Liansheng Zhao ◽

Mingli Li ◽

...

Keyword(s):

Cortical Thickness ◽

Gray Matter ◽

Brain Structure ◽

Gray Matter Volume ◽

Factor H ◽

Major Depressive ◽

Complement Components ◽

Factor B ◽

Matter Volume ◽

Patient Groups

Abstract Objective Inflammation plays a crucial role in the pathogenesis of major depressive disorder (MDD) and bipolar disorder (BD). However, the underlying neurobiological mechanisms are poorly understood. This study aimed to examine whether the dysregulation of complement components contributes to brain structure deficits in BD and MDD patients. Methods A total of 52 BD patients, 35 MDD patients, and 53 mentally healthy controls were recruited from the inpatient and outpatient departments of West China Hospital of Sichuan University. The human complement panel 2-immunology multiplex assay was used to measure the levels of complement C1q, C3, C3b, C4, factor B, factor H, and properdin. Whole brain-based comparison was performed to investigate differences in gray matter volume and cortical thickness among the BD, MDD, and control groups, and relationships were explored between neuroanatomical differences and levels of complement components.Results The gray matter volume in the medial orbital frontal cortex (mOFC) and middle cingulum decreased in both patient groups, while the cortical thickness of the left precentral and left superior frontal gyrus was affected differently. Log10-transformed concentrations of C1q, C4, factor B, factor H, and properdin were higher in both patient groups than in controls, while levels of C1q, factor H, and properdin showed a significant negative correlation with gray matter volume in the mOFC at the voxel-wise level.Conclusion Greater inflammation in mOFC was observed in BD and MDD patients than in controls. Structural deficits in both patient groups were associated with elevated levels of certain complement factors, providing insight into the neuro-inflammatory pathogenesis of mood disorders.

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Contralesional macrostructural plasticity of the insular cortex in patients with glioma

Neurology ◽

10.1212/wnl.0000000000006517 ◽

2018 ◽

Vol 91 (20) ◽

pp. e1902-e1908 ◽

Cited By ~ 15

Author(s):

Fabien Almairac ◽

Hugues Duffau ◽

Guillaume Herbet

Keyword(s):

Gray Matter ◽

Gray Matter Volume ◽

Region Of Interest ◽

Insular Cortex ◽

Low Grade ◽

Healthy Controls ◽

Matter Volume ◽

Patient Groups ◽

The Right ◽

High Level

ObjectiveTo assess the homotopic structural plasticity in case of unilateral damage of the insula.MethodsTo detect changes in gray matter volumes of the contralesional insula from structural MRIs, we used voxel-based morphometry (VBM) in a sample of 84 patients with a diffuse low-grade glioma invading the left insula (insL group; n = 47) or the right insula (insR group; n = 37).ResultsThe region of interest–based VBM analysis highlighted a large cluster of voxels with gray matter volume increase in the contralesional insula in both patient groups (k = 2,214 voxels for insL and k = 879 voxels for insR, p < 0.05, family-wise error corrected) compared with 24 age-matched healthy controls. Gray matter volume was increased for the entire insula (t69 = 3.63, p = 0.0016 for insL; t59 = 3.54, p = 0.0024 for insR, Bonferroni corrected), whereas no significant changes were found in 2 control regions for both patient groups. Furthermore, an increase of 24.6% and 31.6% in the gray matter volume was observed in the insula-related VBM cluster for insL and insR patients, respectively, compared with healthy controls (t69 = 7.39, p = 2.59 × 10−10 and t59 = 7.51, p = 3.61 × 10−10).ConclusionsThe reported results demonstrate that slow-growing but massive lesion infiltration of the insula induces marked increase of gray matter volume in the contralateral one. Our findings give support for a homotopic reorganization that might be a physiologic basis for the high level of functional compensation observed in patients with glioma.

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