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1.
PLoS Comput Biol ; 20(5): e1011350, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38701063

RESUMO

A fundamental challenge in neuroscience is accurately defining brain states and predicting how and where to perturb the brain to force a transition. Here, we investigated resting-state fMRI data of patients suffering from disorders of consciousness (DoC) after coma (minimally conscious and unresponsive wakefulness states) and healthy controls. We applied model-free and model-based approaches to help elucidate the underlying brain mechanisms of patients with DoC. The model-free approach allowed us to characterize brain states in DoC and healthy controls as a probabilistic metastable substate (PMS) space. The PMS of each group was defined by a repertoire of unique patterns (i.e., metastable substates) with different probabilities of occurrence. In the model-based approach, we adjusted the PMS of each DoC group to a causal whole-brain model. This allowed us to explore optimal strategies for promoting transitions by applying off-line in silico probing. Furthermore, this approach enabled us to evaluate the impact of local perturbations in terms of their global effects and sensitivity to stimulation, which is a model-based biomarker providing a deeper understanding of the mechanisms underlying DoC. Our results show that transitions were obtained in a synchronous protocol, in which the somatomotor network, thalamus, precuneus and insula were the most sensitive areas to perturbation. This motivates further work to continue understanding brain function and treatments of disorders of consciousness.


Assuntos
Encéfalo , Simulação por Computador , Transtornos da Consciência , Imageamento por Ressonância Magnética , Modelos Neurológicos , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/fisiopatologia , Encéfalo/diagnóstico por imagem , Transtornos da Consciência/fisiopatologia , Transtornos da Consciência/diagnóstico por imagem , Masculino , Feminino , Biologia Computacional , Adulto , Pessoa de Meia-Idade , Estado de Consciência/fisiologia , Mapeamento Encefálico/métodos , Idoso
2.
Neuroimage ; 293: 120623, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38670442

RESUMO

High-order interactions are required across brain regions to accomplish specific cognitive functions. These functional interdependencies are reflected by synergistic information that can be obtained by combining the information from all the sources considered and redundant information (i.e., common information provided by all the sources). However, electroencephalogram (EEG) functional connectivity is limited to pairwise interactions thereby precluding the estimation of high-order interactions. In this multicentric study, we used measures of synergistic and redundant information to study in parallel the high-order interactions between five EEG electrodes during three non-ordinary states of consciousness (NSCs): Rajyoga meditation (RM), hypnosis, and auto-induced cognitive trance (AICT). We analyzed EEG data from 22 long-term Rajyoga meditators, nine volunteers undergoing hypnosis, and 21 practitioners of AICT. We here report the within-group changes in synergy and redundancy for each NSC in comparison with their respective baseline. During RM, synergy increased at the whole brain level in the delta and theta bands. Redundancy decreased in frontal, right central, and posterior electrodes in delta, and frontal, central, and posterior electrodes in beta1 and beta2 bands. During hypnosis, synergy decreased in mid-frontal, temporal, and mid-centro-parietal electrodes in the delta band. The decrease was also observed in the beta2 band in the left frontal and right parietal electrodes. During AICT, synergy decreased in delta and theta bands in left-frontal, right-frontocentral, and posterior electrodes. The decrease was also observed at the whole brain level in the alpha band. However, redundancy changes during hypnosis and AICT were not significant. The subjective reports of absorption and dissociation during hypnosis and AICT, as well as the mystical experience questionnaires during AICT, showed no correlation with the high-order measures. The proposed study is the first exploratory attempt to utilize the concepts of synergy and redundancy in NSCs. The differences in synergy and redundancy during different NSCs warrant further studies to relate the extracted measures with the phenomenology of the NSCs.


Assuntos
Estado de Consciência , Eletroencefalografia , Hipnose , Meditação , Humanos , Masculino , Feminino , Adulto , Estado de Consciência/fisiologia , Pessoa de Meia-Idade , Encéfalo/fisiologia , Adulto Jovem
3.
Semin Neurol ; 44(3): 271-280, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38604229

RESUMO

Cognitive motor dissociation (CMD) is characterized by a dissociation between volitional brain responses and motor control, detectable only through techniques such as electroencephalography (EEG) and functional magnetic resonance imaging. Hence, it has recently emerged as a major challenge in the assessment of patients with disorders of consciousness. Specifically, this review focuses on the prognostic implications of CMD detection during the acute stage of brain injury. CMD patients were identified in each diagnostic category (coma, unresponsive wakefulness syndrome/vegetative state, minimally conscious state minus) with a relatively similar prevalence of around 20%. Current knowledge tends to indicate that the diagnosis of CMD in the acute phase often predicts a more favorable clinical outcome compared with other unresponsive non-CMD patients. Nevertheless, the review underscores the limited research in this domain, probably at least partially explained by its nascent nature and the lack of uniformity in the nomenclature for CMD-related disorders, hindering the impact of the literature in the field.


Assuntos
Transtornos da Consciência , Humanos , Transtornos da Consciência/diagnóstico , Transtornos da Consciência/fisiopatologia , Transtornos Dissociativos/diagnóstico , Transtornos Dissociativos/fisiopatologia , Prognóstico
4.
Cereb Cortex ; 33(11): 7193-7210, 2023 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-36977648

RESUMO

Neurophysiological markers can overcome the limitations of behavioural assessments of Disorders of Consciousness (DoC). EEG alpha power emerged as a promising marker for DoC, although long-standing literature reported alpha power being sustained during anesthetic-induced unconsciousness, and reduced during dreaming and hallucinations. We hypothesized that EEG power suppression caused by severe anoxia could explain this conflict. Accordingly, we split DoC patients (n = 87) in postanoxic and non-postanoxic cohorts. Alpha power was suppressed only in severe postanoxia but failed to discriminate un/consciousness in other aetiologies. Furthermore, it did not generalize to an independent reference dataset (n = 65) of neurotypical, neurological, and anesthesia conditions. We then investigated EEG spatio-spectral gradients, reflecting anteriorization and slowing, as alternative markers. In non-postanoxic DoC, these features, combined in a bivariate model, reliably stratified patients and indexed consciousness, even in unresponsive patients identified as conscious by an independent neural marker (the Perturbational Complexity Index). Crucially, this model optimally generalized to the reference dataset. Overall, alpha power does not index consciousness; rather, its suppression entails diffuse cortical damage, in postanoxic patients. As an alternative, EEG spatio-spectral gradients, reflecting distinct pathophysiological mechanisms, jointly provide a robust, parsimonious, and generalizable marker of consciousness, whose clinical application may guide rehabilitation efforts.


Assuntos
Anestesia , Estado de Consciência , Humanos , Estado de Consciência/fisiologia , Transtornos da Consciência , Eletroencefalografia , Inconsciência/induzido quimicamente
5.
Qual Life Res ; 33(2): 481-490, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37971668

RESUMO

OBJECTIVES: Long-term care of severe brain injury patients places a significant mental burden on family caregivers, yet few studies have reported the situation in China. We aimed to describe the mood states of family caregivers of patients with severe brain injury and examine the influencing factors that affect caregivers' moods. METHODS: Cross-sectional survey was used to assess the mood profiles of Chinese family caregivers between February 2019 and February 2020. Demographic data of caregivers and patients, the Patient Health Questionnaire (PHQ-9) and the Generalized Anxiety Disorder scale (GAD-7) were used to assess the level of depressive and anxiety symptoms. The quality of life score was also assessed by a visual analog scale, and the Coma Recovery Scale-Revised was used to assess the patient's consciousness. RESULT: One hundred and one patients with severe brain injury (57 unresponsive wakefulness syndrome, UWS) between the age of 14 and 70 and their main family caregivers were enrolled in the study. Most caregivers displayed depressive (n = 62) and anxiety symptoms (n = 65), with 17 and 20 of these family caregivers reporting (moderately) severe depressive symptom and severe anxiety symptom, respectively. The caregiver's depressive symptom level significantly decreased as the patient's injury lasted longer (r = - 0.208, P = 0.037). Moreover, the age of the patient negatively related to the levels of depressive (r = - 0.310, P = 0.002) and anxiety symptoms (r = - 0.289, P = 0.003) in caregivers. There was a significant positive correlation between anxiety and depressive symptoms scores in family caregivers (r = 0.838, P < 0.001). The higher the level of anxiety (r = - 0.273, P = 0.006) and depressive symptoms (r = - 0.265, P = 0.007), the worse the quality of life. CONCLUSION: Many family caregivers of patients with severe brain injury experience various levels of anxiety and depressive symptoms in China. Tailor-made psychological help seems imperative. Researchers and doctors can provide information about patient's conditions to assist family members in discussing rehabilitation options for patients in different states of consciousness will help to ease anxiety of family caregivers.


Assuntos
Lesões Encefálicas , Cuidadores , Humanos , Cuidadores/psicologia , Qualidade de Vida/psicologia , Estudos Transversais , Ansiedade/psicologia , Depressão/psicologia , Família/psicologia
6.
Neurocrit Care ; 40(1): 81-98, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37349602

RESUMO

BACKGROUND: Patients with disorders of consciousness who are behaviorally unresponsive may demonstrate volitional brain responses to motor imagery or motor commands detectable on functional magnetic resonance imaging or electroencephalography. This state of cognitive motor dissociation (CMD) may have prognostic significance. METHODS: The Neurocritical Care Society's Curing Coma Campaign identified an international group of experts who convened in a series of monthly online meetings between September 2021 and April 2023 to examine the science of CMD and identify key knowledge gaps and unmet needs. RESULTS: The group identified major knowledge gaps in CMD research: (1) lack of information about patient experiences and caregiver accounts of CMD, (2) limited epidemiological data on CMD, (3) uncertainty about underlying mechanisms of CMD, (4) methodological variability that limits testing of CMD as a biomarker for prognostication and treatment trials, (5) educational gaps for health care personnel about the incidence and potential prognostic relevance of CMD, and (6) challenges related to identification of patients with CMD who may be able to communicate using brain-computer interfaces. CONCLUSIONS: To improve the management of patients with disorders of consciousness, research efforts should address these mechanistic, epidemiological, bioengineering, and educational gaps to enable large-scale implementation of CMD assessment in clinical practice.


Assuntos
Lesões Encefálicas , Transtornos da Consciência , Humanos , Encéfalo , Estado de Consciência/fisiologia , Imageamento por Ressonância Magnética
7.
Neurocrit Care ; 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38286946

RESUMO

BACKGROUND: We developed a gap analysis that examines the role of brain-computer interfaces (BCI) in patients with disorders of consciousness (DoC), focusing on their assessment, establishment of communication, and engagement with their environment. METHODS: The Curing Coma Campaign convened a Coma Science work group that included 16 clinicians and neuroscientists with expertise in DoC. The work group met online biweekly and performed a gap analysis of the primary question. RESULTS: We outline a roadmap for assessing BCI readiness in patients with DoC and for advancing the use of BCI devices in patients with DoC. Additionally, we discuss preliminary studies that inform development of BCI solutions for communication and assessment of readiness for use of BCIs in DoC study participants. Special emphasis is placed on the challenges posed by the complex pathophysiologies caused by heterogeneous brain injuries and their impact on neuronal signaling. The differences between one-way and two-way communication are specifically considered. Possible implanted and noninvasive BCI solutions for acute and chronic DoC in adult and pediatric populations are also addressed. CONCLUSIONS: We identify clinical and technical gaps hindering the use of BCI in patients with DoC in each of these contexts and provide a roadmap for research aimed at improving communication for adults and children with DoC, spanning the clinical spectrum from intensive care unit to chronic care.

8.
J Cogn Neurosci ; 35(9): 1394-1409, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37315333

RESUMO

Hypnosis has been shown to be of clinical utility; however, its underlying neural mechanisms remain unclear. This study aims to investigate altered brain dynamics during the non-ordinary state of consciousness induced by hypnosis. We studied high-density EEG in 9 healthy participants during eyes-closed wakefulness and during hypnosis, induced by a muscle relaxation and eyes fixation procedure. Using hypotheses based on internal and external awareness brain networks, we assessed region-wise brain connectivity between six ROIs (right and left frontal, right and left parietal, upper and lower midline regions) at the scalp level and compared across conditions. Data-driven, graph-theory analyses were also carried out to characterize brain network topology in terms of brain network segregation and integration. During hypnosis, we observed (1) increased delta connectivity between left and right frontal, as well as between right frontal and parietal regions; (2) decreased connectivity for alpha (between right frontal and parietal and between upper and lower midline regions) and beta-2 bands (between upper midline and right frontal, frontal and parietal, also between upper and lower midline regions); and (3) increased network segregation (short-range connections) in delta and alpha bands, and increased integration (long-range connections) in beta-2 band. This higher network integration and segregation was measured bilaterally in frontal and right parietal electrodes, which were identified as central hub regions during hypnosis. This modified connectivity and increased network integration-segregation properties suggest a modification of the internal and external awareness brain networks that may reflect efficient cognitive-processing and lower incidences of mind-wandering during hypnosis.


Assuntos
Estado de Consciência , Hipnose , Humanos , Estado de Consciência/fisiologia , Encéfalo/diagnóstico por imagem , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/fisiologia , Vigília , Mapeamento Encefálico
9.
Hum Brain Mapp ; 44(11): 4352-4371, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37254960

RESUMO

The study of the brain's dynamical activity is opening a window to help the clinical assessment of patients with disorders of consciousness. For example, glucose uptake and the dysfunctional spread of naturalistic and synthetic stimuli has proven useful to characterize hampered consciousness. However, understanding of the mechanisms behind loss of consciousness following brain injury is still missing. Here, we study the propagation of endogenous and in-silico exogenous perturbations in patients with disorders of consciousness, based upon directed and causal interactions estimated from resting-state fMRI data, fitted to a linear model of activity propagation. We found that patients with disorders of consciousness suffer decreased capacity for neural propagation and responsiveness to events, and that this can be related to severe reduction of glucose metabolism as measured with [18 F]FDG-PET. In particular, we show that loss of consciousness is related to the malfunctioning of two neural circuits: the posterior cortical regions failing to convey information, in conjunction with reduced broadcasting of information from subcortical, temporal, parietal and frontal regions. These results shed light on the mechanisms behind disorders of consciousness, triangulating network function with basic measures of brain integrity and behavior.


Assuntos
Transtornos da Consciência , Estado de Consciência , Humanos , Transtornos da Consciência/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Fluordesoxiglucose F18 , Inconsciência
10.
PLoS Comput Biol ; 18(9): e1010412, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36067227

RESUMO

The self-organising global dynamics underlying brain states emerge from complex recursive nonlinear interactions between interconnected brain regions. Until now, most efforts of capturing the causal mechanistic generating principles have supposed underlying stationarity, being unable to describe the non-stationarity of brain dynamics, i.e. time-dependent changes. Here, we present a novel framework able to characterise brain states with high specificity, precisely by modelling the time-dependent dynamics. Through describing a topological structure associated to the brain state at each moment in time (its attractor or 'information structure'), we are able to classify different brain states by using the statistics across time of these structures hitherto hidden in the neuroimaging dynamics. Proving the strong potential of this framework, we were able to classify resting-state BOLD fMRI signals from two classes of post-comatose patients (minimally conscious state and unresponsive wakefulness syndrome) compared with healthy controls with very high precision.


Assuntos
Encéfalo , Estado Vegetativo Persistente , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Neuroimagem , Vigília
11.
Eur J Neurol ; 30(10): 3016-3031, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37515394

RESUMO

BACKGROUND AND PURPOSE: Transcranial direct current stimulation (tDCS) has been shown to improve signs of consciousness in a subset of patients with disorders of consciousness (DoC). However, no multicentre study confirmed its efficacy when applied during rehabilitation. In this randomized controlled double-blind study, the effects of tDCS whilst patients were in rehabilitation were tested at the group level and according to their diagnosis and aetiology to better target DoC patients who might repond to tDCS. METHODS: Patients received 2 mA tDCS or sham applied over the left prefrontal cortex for 4 weeks. Behavioural assessments were performed weekly and up to 3 months' follow-up. Analyses were conducted at the group and subgroup levels based on the diagnosis (minimally conscious state [MCS] and unresponsive wakefulness syndrome) and the aetiology (traumatic or non-traumatic). Interim analyses were planned to continue or stop the trial. RESULTS: The trial was stopped for futility when 62 patients from 10 centres were enrolled (44 ± 14 years, 37 ± 24.5 weeks post-injury, 18 women, 32 MCS, 39 non-traumatic). Whilst, at the group level, no treatment effect was found, the subgroup analyses at 3 months' follow-up revealed a significant improvement for patients in MCS and with traumatic aetiology. CONCLUSIONS: Transcranial direct current stimulation during rehabilitation does not seem to enhance patients' recovery. However, diagnosis and aetiology appear to be important factors leading to a response to the treatment. These findings bring novel insights into possible cortical plasticity changes in DoC patients given these differential results according to the subgroups of patients.


Assuntos
Estimulação Transcraniana por Corrente Contínua , Humanos , Feminino , Estimulação Transcraniana por Corrente Contínua/métodos , Resultado do Tratamento , Transtornos da Consciência/terapia , Transtornos da Consciência/diagnóstico , Córtex Pré-Frontal , Estado Vegetativo Persistente/terapia , Estado Vegetativo Persistente/diagnóstico
12.
Crit Care ; 27(1): 76, 2023 02 27.
Artigo em Inglês | MEDLINE | ID: mdl-36849984

RESUMO

BACKGROUND: So far, the few prospective studies on near-death experience (NDE) were carried out only in intensive care unit (ICU) patients with homogeneous aetiologies, such as cardiac arrest or trauma survivors. The aims of this 1-year prospective and monocentric study were to investigate the incidence of NDE in ICU survivors (all aetiologies) as well as factors that may affect its frequency, and to assess quality of life up to 1 year after enrolment. METHODS: We enrolled adults with a prolonged ICU stay (> 7 days). During the first 7 days after discharge, all eligible patients were assessed in a face-to-face interview for NDE using the Greyson NDE scale, dissociative experiences using the Dissociative Experience Scale, and spirituality beliefs using the WHOQOL-SRPB. Medical parameters were prospectively collected. At 1-year after inclusion, patients were contacted by phone to measure quality of life using the EuroQol five-dimensional questionnaire. RESULTS: Out of the 126 included patients, 19 patients (15%) reported having experienced a NDE as identified by the Greyson NDE scale (i.e. cut-off score ≥ 7/32). In univariate analyses, mechanical ventilation, sedation, analgesia, reason for admission, primary organ dysfunction, dissociative and spiritual propensities were associated with the emergence of NDE. In multivariate logistic regression analysis, only the dissociative and spiritual propensity strongly predicted the emergence of NDE. One year later (n = 61), the NDE was not significantly associated with quality of life. CONCLUSIONS: The recall of NDE is not so rare in the ICU. In our cohort, cognitive and spiritual factors outweighed medical parameters as predictors of the emergence of NDE. Trial registration This trial was registered in Clinicaltrials.gov in February 2020 ( NCT04279171 ).


Assuntos
Estado Terminal , Qualidade de Vida , Adulto , Humanos , Incidência , Estado Terminal/epidemiologia , Estudos Prospectivos , Morte
13.
Br J Anaesth ; 131(4): 715-725, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37596183

RESUMO

BACKGROUND: Cortical excitability is higher in unconsciousness than in wakefulness, but it is unclear how this relates to anaesthesia. We investigated cortical excitability in response to dexmedetomidine, the effects of which are not fully known. METHODS: We recorded transcranial magnetic stimulation (TMS) and EEG in frontal and parietal cortex of 20 healthy subjects undergoing dexmedetomidine sedation in four conditions (baseline, light sedation, deep sedation, recovery). We used the first component (0-30 ms) of the TMS-evoked potential (TEP) to measure cortical excitability (amplitude), slope, and positive and negative peak latencies (collectively, TEP indices). We used generalised linear mixed models to test the effect of condition, brain region, and responsiveness on TEP indices. RESULTS: Compared with baseline, amplitude in the frontal cortex increased by 6.52 µV (P<0.001) in light sedation, 4.55 µV (P=0.003) in deep sedation, and 5.03 µV (P<0.001) in recovery. Amplitude did not change in the parietal cortex. Compared with baseline, slope increased in all conditions (P<0.02) in the frontal but not parietal cortex. The frontal cortex showed 5.73 µV higher amplitude (P<0.001), 0.63 µV ms-1 higher slope (P<0.001), and 2.2 ms shorter negative peak latency (P=0.001) than parietal areas. Interactions between dexmedetomidine and region had effects over amplitude (P=0.004) and slope (P=0.009), with both being higher in light sedation, deep sedation, and recovery compared with baseline. CONCLUSIONS: Transcranial magnetic stimulation-evoked potential amplitude changes non-linearly as a function of depth of sedation by dexmedetomidine, with a region-specific paradoxical increase. Future research should investigate other anaesthetics to elucidate the link between cortical excitability and depth of sedation.


Assuntos
Anestesia , Dexmedetomidina , Humanos , Estimulação Magnética Transcraniana , Dexmedetomidina/farmacologia , Potenciais Evocados , Lobo Frontal
14.
Brain Inj ; 37(1): 54-62, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36426606

RESUMO

BACKGROUND: Nutritional status of patients with disorders of consciousness (DoC) is poorly studied. OBJECTIVES: To evaluate the relationship between nutritional status (body mass index, daily calories intake) and clinical variables (level of consciousness, time since injury, diagnosis, etiology and spastic muscle overactivity; SMO,) in patients with prolonged DoCor emerging. Our main hypotheses are i) patients with lower level of consciousness (UWS) have worse nutritional status compared to patients in minimally conscious state (MCS) and ii) SMO could influence nutritional status. METHODS AND RESULTS: Among the 80 patients included in the study (19 UWS, 47 MCS, 14 emerging MCS; 43 ± 15 yo; 3 ± 4 years post-injury, 35 traumatic etiology, 34 females), 9% were at risk to be undernourished, with no differences between UWS and MCS. Patients without SMO had a higher BMI compared to patients with severe SMO. Compared to the recommended daily calories intake, patients with the highest BMI received less calories and patients with the lowest BMI received more calories. We observed a negative correlation between SMO (in lower limbs) and BMI. CONCLUSION: Our study shows that most patients are well nourished, independently from the level of consciousness. SMO may require additional calories in patients' daily needs; however, longitudinal studies are needed to explore the causal relationship between these variables.


Assuntos
Transtornos da Consciência , Estado Nutricional , Feminino , Humanos , Estudos Retrospectivos , Estudos Transversais , Transtornos da Consciência/etiologia , Transtornos da Consciência/diagnóstico , Prognóstico , Estado Vegetativo Persistente/etiologia , Estado Vegetativo Persistente/diagnóstico , Estado de Consciência/fisiologia
15.
Neurocrit Care ; 39(3): 611-617, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37552410

RESUMO

BACKGROUND: Over the past 5 decades, advances in neuroimaging have yielded insights into the pathophysiologic mechanisms that cause disorders of consciousness (DoC) in patients with severe brain injuries. Structural, functional, metabolic, and perfusion imaging studies have revealed specific neuroanatomic regions, such as the brainstem tegmentum, thalamus, posterior cingulate cortex, medial prefrontal cortex, and occipital cortex, where lesions correlate with the current or future state of consciousness. Advanced imaging modalities, such as diffusion tensor imaging, resting-state functional magnetic resonance imaging (fMRI), and task-based fMRI, have been used to improve the accuracy of diagnosis and long-term prognosis, culminating in the endorsement of fMRI for the clinical evaluation of patients with DoC in the 2018 US (task-based fMRI) and 2020 European (task-based and resting-state fMRI) guidelines. As diverse neuroimaging techniques are increasingly used for patients with DoC in research and clinical settings, the need for a standardized approach to reporting results is clear. The success of future multicenter collaborations and international trials fundamentally depends on the implementation of a shared nomenclature and infrastructure. METHODS: To address this need, the Neurocritical Care Society's Curing Coma Campaign convened an international panel of DoC neuroimaging experts to propose common data elements (CDEs) for data collection and reporting in this field. RESULTS: We report the recommendations of this CDE development panel and disseminate CDEs to be used in neuroimaging studies of patients with DoC. CONCLUSIONS: These CDEs will support progress in the field of DoC neuroimaging and facilitate international collaboration.


Assuntos
Estado de Consciência , Imagem de Tensor de Difusão , Humanos , Estado de Consciência/fisiologia , Imagem de Tensor de Difusão/efeitos adversos , Transtornos da Consciência/etiologia , Elementos de Dados Comuns , Neuroimagem/métodos , Imageamento por Ressonância Magnética/métodos
16.
Dysphagia ; 38(1): 42-64, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35773497

RESUMO

This literature review explores a wide range of themes addressing the links between swallowing and consciousness. Signs of consciousness are historically based on the principle of differentiating reflexive from volitional behaviors. We show that the sequencing of the components of swallowing falls on a continuum of voluntary to reflex behaviors and we describe several types of volitional and non-volitional swallowing tasks. The frequency, speed of initiation of the swallowing reflex, efficacy of the pharyngeal phase of swallowing and coordination between respiration and swallowing are influenced by the level of consciousness during non-pathological modifications of consciousness such as sleep and general anesthesia. In patients with severe brain injury, the level of consciousness is associated with several components related to swallowing, such as the possibility of extubation, risk of pneumonia, type of feeding or components directly related to swallowing such as oral or pharyngeal abnormalities. Based on our theoretical and empirical analysis, the efficacy of the oral phase and the ability to receive exclusive oral feeding seem to be the most robust signs of consciousness related to swallowing in patients with disorders of consciousness. Components of the pharyngeal phase (in terms of abilities of saliva management) and evoked cough may be influenced by consciousness, but further studies are necessary to determine if they constitute signs of consciousness as such or only cortically mediated behaviors. This review also highlights the critical lack of tools and techniques to assess and treat dysphagia in patients with disorders of consciousness.


Assuntos
Transtornos de Deglutição , Deglutição , Humanos , Deglutição/fisiologia , Estado de Consciência , Transtornos da Consciência/etiologia , Transtornos de Deglutição/etiologia , Transtornos de Deglutição/diagnóstico , Reflexo/fisiologia
17.
J Neurosci ; 41(24): 5251-5262, 2021 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-33758019

RESUMO

The neural monitoring of visceral inputs might play a role in first-person perspective (i.e., the unified viewpoint of subjective experience). In healthy participants, how the brain responds to heartbeats, measured as the heartbeat-evoked response (HER), correlates with perceptual, bodily, and self-consciousness. Here we show that HERs in resting-state EEG data distinguishes between postcomatose male and female human patients (n = 68, split into training and validation samples) with the unresponsive wakefulness syndrome and in patients in a minimally conscious state with high accuracy (random forest classifier, 87% accuracy, 96% sensitivity, and 50% specificity in the validation sample). Random EEG segments not locked to heartbeats were useful to predict unconsciousness/consciousness, but HERs were more accurate, indicating that HERs provide specific information on consciousness. HERs also led to more accurate classification than heart rate variability. HER-based consciousness scores correlate with glucose metabolism in the default-mode network node located in the right superior temporal sulcus, as well as with the right ventral occipitotemporal cortex. These results were obtained when consciousness was inferred from brain glucose met`abolism measured with positron emission topography. HERs reflected the consciousness diagnosis based on brain metabolism better than the consciousness diagnosis based on behavior (Coma Recovery Scale-Revised, 77% validation accuracy). HERs thus seem to capture a capacity for consciousness that does not necessarily translate into intentional overt behavior. These results confirm the role of HERs in consciousness, offer new leads for future bedside testing, and highlight the importance of defining consciousness and its neural mechanisms independently from behavior.


Assuntos
Encéfalo/fisiopatologia , Coma/fisiopatologia , Frequência Cardíaca , Monitorização Neurofisiológica/métodos , Estado Vegetativo Persistente/fisiopatologia , Adolescente , Adulto , Idoso , Eletroencefalografia/métodos , Feminino , Humanos , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador , Adulto Jovem
18.
Annu Rev Neurosci ; 37: 457-78, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25002279

RESUMO

Significant advances have been made in the behavioral assessment and clinical management of disorders of consciousness (DOC). In addition, functional neuroimaging paradigms are now available to help assess consciousness levels in this challenging patient population. The success of these neuroimaging approaches as diagnostic markers is, however, intrinsically linked to understanding the relationships between consciousness and the brain. In this context, a combined theoretical approach to neuroimaging studies is needed. The promise of such theoretically based markers is illustrated by recent findings that used a perturbational approach to assess the levels of consciousness. Further research on the contents of consciousness in DOC is also needed.


Assuntos
Encéfalo/fisiopatologia , Coma/diagnóstico , Coma/fisiopatologia , Estado de Consciência , Estado Vegetativo Persistente/diagnóstico , Estado Vegetativo Persistente/fisiopatologia , Neuroimagem Funcional , Humanos , Quadriplegia/diagnóstico , Quadriplegia/fisiopatologia
19.
Curr Opin Oncol ; 34(4): 270-278, 2022 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-35730502

RESUMO

PURPOSE OF REVIEW: Cancer-related fatigue (CRF) and sleep disturbances are common symptoms among patients with cancer. They are often conceptualized as a part of a larger symptom cluster, also comprising pain and emotional distress. Despite their prevalence and long-lasting effects, CRF and sleep disturbances are still poorly addressed in clinical settings. Specific interventions are needed to manage these symptoms. RECENT FINDINGS: In addition to conventional pharmacological therapies, other kinds of interventions are increasingly being developed in oncology. This review will discuss three categories of interventions for patients with cancer and their interest in alleviating CRF and sleep disturbances: physical exercises (e.g., aerobic, resistance training, running, free weights), psychological interventions (e.g., cognitive-behavioural therapy, psychoeducational interventions), and mind-body interventions (e.g., yoga, mindfulness, hypnosis). The multicomponent aspect of these interventions seems particularly important to address these symptoms. SUMMARY: The findings detailed in this review will allow the scientific community, as well as health professionals working in oncology settings, to be informed about new nonpharmacological therapeutic options to help patients to manage their symptoms. It could eventually help to improve existing interventions for these patients.


Assuntos
Neoplasias , Psico-Oncologia , Fadiga/etiologia , Fadiga/terapia , Humanos , Terapias Mente-Corpo , Neoplasias/complicações , Neoplasias/psicologia , Neoplasias/terapia , Sono
20.
Ann Neurol ; 90(1): 89-100, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33938027

RESUMO

OBJECTIVE: Brain-injured patients who are unresponsive at the bedside (ie, vegetative state/unresponsive wakefulness syndrome - VS/UWS) may present brain activity similar to patients in minimally conscious state (MCS). This peculiar condition has been termed "non-behavioural MCS" or "MCS*". In the present study we aimed to investigate the proportion and underlying brain characteristics of patients in MCS*. METHODS: Brain 18 F-fluorodeoxyglucose Positron Emission Tomography (FDG-PET) was acquired on 135 brain-injured patients diagnosed in prolonged VS/UWS (n = 48) or MCS (n = 87). From an existing database, relative metabolic preservation in the fronto-parietal network (measured with standardized uptake value) was visually inspected by three experts. Patients with hypometabolism of the fronto-parietal network were labelled "VS/UWS", while its (partial) preservation either confirmed the behavioural diagnosis of "MCS" or, in absence of behavioural signs of consciousness, suggested a diagnosis of "MCS*". Clinical outcome at 1-year follow-up, functional connectivity, grey matter atrophy, and regional brain metabolic patterns were investigated in the three groups (VS/UWS, MCS* and MCS). RESULTS: 67% of behavioural VS/UWS presented a partial preservation of brain metabolism (ie, MCS*). Compared to VS/UWS patients, MCS* patients demonstrated a better outcome, global functional connectivity and grey matter preservation more compatible with the diagnosis of MCS. MCS* patients presented lower brain metabolism mostly in the posterior brain regions compared to MCS patients. INTERPRETATION: MCS* is a frequent phenomenon that is associated with better outcome and better brain preservation than the diagnosis of VS/UWS. Complementary exams should be provided to all unresponsive patients before taking medical decisions. ANN NEUROL 2021;90:89-100.


Assuntos
Encéfalo/diagnóstico por imagem , Estado de Consciência/fisiologia , Estado Vegetativo Persistente/diagnóstico por imagem , Adulto , Idoso , Encéfalo/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estado Vegetativo Persistente/fisiopatologia , Tomografia por Emissão de Pósitrons , Adulto Jovem
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