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1.
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
2.
BMC Cancer ; 24(1): 51, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195471

RESUMO

BACKGROUND: A psychoneurological symptom cluster composed of cancer-related fatigue, emotional distress, sleep difficulties, and pain is very common among patients with cancer. Cognitive difficulties are also frequently associated with this cluster. Network analyses allow for an in-depth understanding of the relationships between symptoms in a cluster. This paper details the study protocol of a longitudinal assessment of the psychoneurological symptom cluster in two distinct cohorts: breast cancer and digestive cancer survivors, using network analyses. METHODS: Over two years, the symptoms involved in the psychoneurological symptom cluster, along with other common symptoms (e.g., digestive symptoms, financial difficulties) and variables (i.e., self-compassion, coping strategies) will be assessed in two cohorts: breast cancer survivors (N = 240) and digestive cancer survivors (N = 240). Online questionnaires will be completed at baseline, then 6, 12 and 24 months later. Network analyses will be used to assess the configuration of the symptom cluster at each measurement time and in each cohort. Comparison of networks between two measurement times or between the two cohorts will also be done with network comparison tests. DISCUSSION: This study will enable a better understanding of the relationships between common symptoms endured by patients with cancer. The results will be employed to develop more cost-effective interventions which, ultimately, will significantly improve the quality of life of patients with breast or digestive cancer. TRIAL REGISTRATION: ClinicalTrials.gov (NCT05867966). Registered on the 27th of April 2023. url: https://classic. CLINICALTRIALS: gov/ct2/show/NCT05867966 .


Assuntos
Neoplasias da Mama , Neoplasias Gastrointestinais , Feminino , Humanos , Mama , Neoplasias da Mama/complicações , Qualidade de Vida , Síndrome , Estudos Observacionais como Assunto
3.
Anesth Analg ; 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38289856

RESUMO

BACKGROUND: Human consciousness is generally thought to emerge from the activity of intrinsic connectivity networks (resting-state networks [RSNs]) of the brain, which have topological characteristics including, among others, graph strength and efficiency. So far, most functional brain imaging studies in anesthetized subjects have compared wakefulness and unresponsiveness, a state considered as corresponding to unconsciousness. Sedation and general anesthesia not only produce unconsciousness but also phenomenological states of preserved mental content and perception of the environment (connected consciousness), and preserved mental content but no perception of the environment (disconnected consciousness). Unresponsiveness may be seen during unconsciousness, but also during disconnectedness. Deep dexmedetomidine sedation is frequently a state of disconnected consciousness. In this study, we were interested in characterizing the RSN topology changes across 4 different and steady-state levels of dexmedetomidine-induced alteration of consciousness, namely baseline (Awake, drug-free state), Mild sedation (drowsy, still responding), Deep sedation (unresponsive), and Recovery, with a focus on changes occurring between a connected consciousness state and an unresponsiveness state. METHODS: A functional magnetic resonance imaging database acquired in 14 healthy volunteers receiving dexmedetomidine sedation was analyzed using a method combining independent component analysis and graph theory, specifically looking at changes in connectivity strength and efficiency occurring during the 4 above-mentioned dexmedetomidine-induced altered consciousness states. RESULTS: Dexmedetomidine sedation preserves RSN architecture. Unresponsiveness during dexmedetomidine sedation is mainly characterized by a between-networks graph strength alteration and within-network efficiency alteration of lower-order sensory RSNs, while graph strength and efficiency in higher-order RSNs are relatively preserved. CONCLUSIONS: The differential dexmedetomidine-induced RSN topological changes evidenced in this study may be the signature of inadequate processing of sensory information by lower-order RSNs, and of altered communication between lower-order and higher-order networks, while the latter remain functional. If replicated in an experimental paradigm distinguishing, in unresponsive subjects, disconnected consciousness from unconsciousness, such changes would sustain the hypothesis that disconnected consciousness arises from altered information handling by lower-order sensory networks and altered communication between lower-order and higher-order networks, while the preservation of higher-order networks functioning allows for an internally generated mental content (or dream).

4.
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
5.
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
6.
Eur J Anaesthesiol ; 39(1): 58-66, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34783683

RESUMO

BACKGROUND: Virtual reality and hypnosis are little studied in complex contexts, such as intensive care, where patients need significant physical and psychological assistance. OBJECTIVES: To compare and combine hypnosis and virtual reality benefits on anxiety and pain on patients before and after cardiac surgery. DESIGN: Prospective randomised controlled clinical trial. SETTING: The study was conducted in the University Hospital of Liege (Belgium) from October 2018 to January 2020. PATIENTS: One hundred patients (66 ±â€Š11.5 years; 24 women, 76 men) were included. Participants were adults undergoing cardiac surgery. Exclusion criteria: psychiatric diseases, claustrophobia, acrophobia, hearing loss, visual impairment, extreme fatigue, confusion surgery cancelled. INTERVENTIONS: Patients were randomly assigned to four arms (control; hypnosis; virtual reality; virtual reality hypnosis) and had 20 min of one of the techniques the day before and the day after surgery. MAIN OUTCOMES MEASURES: Anxiety, pain, fatigue, relaxation, physiological parameters, and opioid use were evaluated before and after each session. RESULTS: The main results did not show any significant differences between the groups. In all groups, anxiety decreased and pain increased from baseline to the postoperative day. Relaxation increased in all groups in the pre-operative (P < 0.0001) and postoperative period (P = 0.03). There were no significant differences for fatigue, physiological measures, or opioid use. CONCLUSION: As there were no significant differences between groups for the measured variables, we cannot affirm that one technique is better than another. Additional studies are required to compare and evaluate the cost-effectiveness of these techniques for critical care patients and caregivers. TRIAL REGISTRATION: ClinicalTrials.gov: NCT03820700. https://clinicaltrials.gov/ct2/show/NCT03820700. Retrospectively registered on 29 January 2019.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Hipnose , Realidade Virtual , Adulto , Ansiedade/diagnóstico , Ansiedade/epidemiologia , Ansiedade/terapia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Manejo da Dor , Transtornos Fóbicos , Estudos Prospectivos
7.
Psychooncology ; 29(7): 1165-1173, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32297396

RESUMO

OBJECTIVE: Cancer has a lot of consequences such as fatigue, sleep disturbances, emotional distress, cognitive impairment and reduced physical activity. Some hypnosis-based psychological interventions showed positive effects on fatigue, sleep and emotional distress, but generally focused on breast cancer patients. Our study aimed at assessing the effects of a group intervention combining self-care and self-hypnosis on quality of life of cancer patients. METHODS: Our longitudinal randomized-controlled trial assessed the benefits of the intervention first on fatigue and secondly on associated symptoms (sleep, emotional distress, cognitive impairment and reduced physical activity) of post-treatment cancer patients, and investigated predictors of the evolution of fatigue. All variables were measured with questionnaires and an actigraph (for sleep and physical activity). RESULTS: Ninety five women with different cancers were included in our study. Group-by-time effects were showed for fatigue, sleep, emotional distress and cognitive functioning: symptoms have improved in the intervention group compared to wait-list control group. Three predictors of the evolution of fatigue were revealed: depression, anxiety and worry. CONCLUSIONS: Our group intervention had benefits for post-treatment cancer patients' quality of life. Impacting emotional distress could be important in order to decrease fatigue. Further studies are needed to replicate our results. This intervention could be easily implemented to improve quality of life of cancer patients. Registration: ClinicalTrials.gov (NCT03144154). Retrospectively registered on the 1st of May, 2017.


Assuntos
Neoplasias da Mama/complicações , Neoplasias da Mama/psicologia , Fadiga/terapia , Hipnose/métodos , Autocuidado/métodos , Adulto , Ansiedade , Neoplasias da Mama/terapia , Cognição , Exercício Físico , Fadiga/etiologia , Feminino , Humanos , Pessoa de Meia-Idade , Qualidade de Vida/psicologia , Sono/fisiologia , Transtornos do Sono-Vigília/etiologia , Transtornos do Sono-Vigília/terapia , Estresse Psicológico , Inquéritos e Questionários , Resultado do Tratamento
8.
Neuroimage ; 200: 450-459, 2019 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-31284028

RESUMO

Functional imaging research has already contributed with several results to the study of neural correlates of consciousness. Apart from task-related activation derived in fMRI, PET based glucose metabolism rate or cerebral blood flow account for a considerable proportion of the study of brain activity under different levels of consciousness. Resting state functional connectivity MRI is playing a crucial role to explore the consciousness related functional integration, successfully complementing PET, another widely used neuroimaging technique. Here, spontaneous hemodynamic response is introduced to characterize resting state brain activity giving information on the local metabolism (neurovascular coupling), and useful to improve the time-resolved activity and connectivity measures based on BOLD fMRI. This voxel-wise measure is then used to investigate the loss of consciousness under Propofol anesthesia and unresponsive wakefulness syndrome. Changes in the hemodynamic response in precuneus and posterior cingulate are found to be a common principle underlying loss of consciousness in both conditions. The thalamus appears to be less obviously modulated by Propofol, compared with frontoparietal regions. However, a significant increase in spontaneous thalamic hemodynamic response was found in patients in unresponsive wakefulness syndrome compared with healthy controls. Our results ultimately show that anesthesia- or pathology-induced neurovascular coupling could be tracked by modulated spontaneous hemodynamic response derived from resting state fMRI.


Assuntos
Córtex Cerebral/fisiologia , Transtornos da Consciência/fisiopatologia , Estado de Consciência/fisiologia , Neuroimagem Funcional/métodos , Acoplamento Neurovascular/fisiologia , Adulto , Córtex Cerebral/diagnóstico por imagem , Transtornos da Consciência/induzido quimicamente , Transtornos da Consciência/diagnóstico por imagem , Feminino , Humanos , Hipnóticos e Sedativos/farmacologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Propofol/farmacologia
9.
Anesthesiology ; 130(6): 898-911, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31045899

RESUMO

BACKGROUND: A key feature of the human brain is its capability to adapt flexibly to changing external stimuli. This capability can be eliminated by general anesthesia, a state characterized by unresponsiveness, amnesia, and (most likely) unconsciousness. Previous studies demonstrated decreased connectivity within the thalamus, frontoparietal, and default mode networks during general anesthesia. We hypothesized that these alterations within specific brain networks lead to a change of communication between networks and their temporal dynamics. METHODS: We conducted a pooled spatial independent component analysis of resting-state functional magnetic resonance imaging data obtained from 16 volunteers during propofol and 14 volunteers during sevoflurane general anesthesia that have been previously published. Similar to previous studies, mean z-scores of the resulting spatial maps served as a measure of the activity within a network. Additionally, correlations of associated time courses served as a measure of the connectivity between networks. To analyze the temporal dynamics of between-network connectivity, we computed the correlation matrices during sliding windows of 1 min and applied k-means clustering to the matrices during both general anesthesia and wakefulness. RESULTS: Within-network activity was decreased in the default mode, attentional, and salience networks during general anesthesia (P < 0.001, range of median changes: -0.34, -0.13). Average between-network connectivity was reduced during general anesthesia (P < 0.001, median change: -0.031). Distinct between-network connectivity patterns for both wakefulness and general anesthesia were observed irrespective of the anesthetic agent (P < 0.001), and there were fewer transitions in between-network connectivity patterns during general anesthesia (P < 0.001, median number of transitions during wakefulness: 4 and during general anesthesia: 0). CONCLUSIONS: These results suggest that (1) higher-order brain regions play a crucial role in the generation of specific between-network connectivity patterns and their dynamics, and (2) the capability to interact with external stimuli is represented by complex between-network connectivity patterns.


Assuntos
Encéfalo/efeitos dos fármacos , Imageamento por Ressonância Magnética/métodos , Rede Nervosa/efeitos dos fármacos , Propofol/administração & dosagem , Sevoflurano/administração & dosagem , Inconsciência/induzido quimicamente , Adulto , Anestésicos Inalatórios/administração & dosagem , Anestésicos Intravenosos/administração & dosagem , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Feminino , Humanos , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/fisiologia , Inconsciência/fisiopatologia , Adulto Jovem
10.
BMC Cancer ; 18(1): 1113, 2018 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-30442120

RESUMO

BACKGROUND: Cancer has a lot of consequences on patients' quality of life (such as cancer-related fatigue (CRF), sleep difficulties and emotional distress) and on patients' partners and their relationship, such as distress and communication difficulties. These consequences are undertreated, and interventions based on hypnosis often focus on breast cancer patients only. This paper describes the study protocol of a longitudinal randomized controlled trial aiming to assess the efficacy of an 8-week intervention combining hypnosis and self-care to improve cancer patients' CRF, sleep and emotional distress and to indirectly improve their partners' distress. METHODS: A power analysis required a total sample of 88 patients. To test the efficacy of the intervention, results of the experimental group receiving the intervention will be compared to those of the control group. Data will be collected by questionnaires, relaxation tasks, an attentional bias task, and everyday life assessments measured at four different times: 1.) before inclusion in the study (baseline); 2.) after the intervention; and 3.) at 4- and 12-month follow-up. Partners' symptoms will also be evaluated with questionnaires at the same measurement times. DISCUSSION: There is a growing interest in alternative approaches (such as hypnosis) in addition to standard therapies in oncology settings. The results of this study should be useful for improving knowledge about long-term efficacy of hypnosis-based group interventions for CRF, sleep and distress among all types of cancer patients and their partners, and to better understand the mechanisms of emotional regulation in cancer patients through the attentional bias task. TRIAL REGISTRATION: ClinicalTrials.gov (NCT03144154). Retrospectively registered on the 1st of May, 2017.


Assuntos
Protocolos Antineoplásicos , Hipnose , Neoplasias/terapia , Qualidade de Vida , Autocuidado/métodos , Adulto , Bélgica , Fadiga/diagnóstico , Fadiga/etiologia , Fadiga/terapia , Humanos , Neoplasias/complicações , Neoplasias/psicologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Sono , Estresse Psicológico/diagnóstico , Estresse Psicológico/psicologia , Estresse Psicológico/terapia , Inquéritos e Questionários , Adulto Jovem
11.
Neuropsychol Rehabil ; 28(8): 1350-1359, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28399715

RESUMO

Different behavioural signs of consciousness can distinguish patients with an unresponsive wakefulness syndrome from patients in minimally conscious state (MCS). The Coma Recovery Scale-Revised (CRS-R) is the most sensitive scale to differentiate the different altered states of consciousness and eleven items detect the MCS. The aim of this study is to document the prevalence of these items. We analysed behavioural assessments of 282 patients diagnosed in MCS based on the CRS-R. Results showed that some items are particularly frequent among patients in MCS, namely fixation, visual pursuit, and reproducible movement to command, which were observed in more than 50% of patients. These responses were also the most probably observed items when the patients only showed one sign of consciousness. On the other hand, some items were rarely or never observed alone, e.g., object localisation (reaching), object manipulation, intelligible verbalisation, and object recognition. The results also showed that limiting the CRS-R assessment to the five most frequently observed items (i.e., fixation, visual pursuit, reproducible movement to command, automatic motor response and localisation to noxious stimulation) detected 99% of the patients in MCS. If clinicians have only limited time to assess patients with disorders of consciousness, we suggest to evaluate at least these five items of the CRS-R.


Assuntos
Transtornos da Consciência/diagnóstico , Transtornos da Consciência/epidemiologia , Movimentos Oculares , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atividade Motora , Prevalência , Reconhecimento Psicológico , Recuperação de Função Fisiológica , Estudos Retrospectivos , Fala
12.
Crit Care Med ; 45(8): e763-e771, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28272153

RESUMO

OBJECTIVES: We hypothesize that the combined use of MRI cortical thickness measurement and subcortical gray matter volumetry could provide an early and accurate in vivo assessment of the structural impact of cardiac arrest and therefore could be used for long-term neuroprognostication in this setting. DESIGN: Prospective cohort study. SETTING: Five Intensive Critical Care Units affiliated to the University in Toulouse (France), Paris (France), Clermont-Ferrand (France), Liège (Belgium), and Monza (Italy). PATIENTS: High-resolution anatomical T1-weighted images were acquired in 126 anoxic coma patients ("learning" sample) 16 ± 8 days after cardiac arrest and 70 matched controls. An additional sample of 18 anoxic coma patients, recruited in Toulouse, was used to test predictive model generalization ("test" sample). All patients were followed up 1 year after cardiac arrest. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Cortical thickness was computed on the whole cortical ribbon, and deep gray matter volumetry was performed after automatic segmentation. Brain morphometric data were employed to create multivariate predictive models using learning machine techniques. Patients displayed significantly extensive cortical and subcortical brain volumes atrophy compared with controls. The accuracy of a predictive classifier, encompassing cortical and subcortical components, has a significant discriminative power (learning area under the curve = 0.87; test area under the curve = 0.96). The anatomical regions which volume changes were significantly related to patient's outcome were frontal cortex, posterior cingulate cortex, thalamus, putamen, pallidum, caudate, hippocampus, and brain stem. CONCLUSIONS: These findings are consistent with the hypothesis of pathologic disruption of a striatopallidal-thalamo-cortical mesocircuit induced by cardiac arrest and pave the way for the use of combined brain quantitative morphometry in this setting.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Parada Cardíaca/patologia , Adulto , Córtex Cerebelar/diagnóstico por imagem , Córtex Cerebelar/patologia , Coma/diagnóstico por imagem , Coma/patologia , Feminino , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos
13.
Anesth Analg ; 124(2): 588-598, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27941576

RESUMO

BACKGROUND: To reduce head movement during resting state functional magnetic resonance imaging, post-coma patients with disorders of consciousness (DOC) are frequently sedated with propofol. However, little is known about the effects of this sedation on the brain connectivity patterns in the damaged brain essential for differential diagnosis. In this study, we aimed to assess these effects. METHODS: Using resting state functional magnetic resonance imaging 3T data obtained over several years of scanning patients for diagnostic and research purposes, we employed a seed-based approach to examine resting state connectivity in higher-order (default mode, bilateral external control, and salience) and lower-order (auditory, sensorimotor, and visual) resting state networks and connectivity with the thalamus, in 20 healthy unsedated controls, 8 unsedated patients with DOC, and 8 patients with DOC sedated with propofol. The DOC groups were matched for age at onset, etiology, time spent in DOC, diagnosis, standardized behavioral assessment scores, movement intensities, and pattern of structural brain injury (as assessed with T1-based voxel-based morphometry). RESULTS: DOC were associated with severely impaired resting state network connectivity in all but the visual network. Thalamic connectivity to higher-order network regions was also reduced. Propofol administration to patients was associated with minor further decreases in thalamic and insular connectivity. CONCLUSIONS: Our findings indicate that connectivity decreases associated with propofol sedation, involving the thalamus and insula, are relatively small compared with those already caused by DOC-associated structural brain injury. Nonetheless, given the known importance of the thalamus in brain arousal, its disruption could well reflect the diminished movement obtained in these patients. However, more research is needed on this topic to fully address the research question.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Sedação Consciente/métodos , Transtornos da Consciência/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Neuroimagem/métodos , Adulto , Idade de Início , Idoso , Lesões Encefálicas/diagnóstico por imagem , Córtex Cerebral/efeitos dos fármacos , Feminino , Humanos , Hipnóticos e Sedativos/farmacologia , Masculino , Pessoa de Meia-Idade , Movimento , Vias Neurais/efeitos dos fármacos , Propofol/farmacologia , Descanso , Tálamo/fisiologia , Adulto Jovem
14.
Brain Inj ; 31(11): 1429-1435, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28980847

RESUMO

OBJECTIVE: Visual pursuit should be tested with a mirror in patients with disorders of consciousness. This stimulus was indeed more efficient than a person or an object, and the auto-referential aspect was supposed to be the key feature. The present study tested the hypothesis that the mirror was more efficient because of its self-aspect. METHODS: The mirror was compared (1) to the patient's picture and to the picture of a famous face, in 22 patients in minimally conscious state and (2) to the patient's picture and a fake mirror, which had dynamical and bright aspects of the mirror, without reflecting the face, in 26 other patients in minimally conscious state. RESULTS: The mirror was more efficient than the patient's picture, which was not statistically different from the famous face. The second part of the study confirmed the statistical difference between the mirror and the picture. However, the fake mirror was neither statistically different from the mirror nor from the picture. CONCLUSIONS: Although our results suggest that the hypothesis proposed by previous studies was partly wrong, they confirm that the mirror is the best stimulus to use when assessing visual pursuit.


Assuntos
Estado Vegetativo Persistente/diagnóstico , Estado Vegetativo Persistente/fisiopatologia , Estimulação Luminosa/métodos , Acompanhamento Ocular Uniforme/fisiologia , Adulto , Idoso , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
15.
Anesthesiology ; 125(5): 873-888, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27496657

RESUMO

BACKGROUND: Consciousness-altering anesthetic agents disturb connectivity between brain regions composing the resting-state consciousness networks (RSNs). The default mode network (DMn), executive control network, salience network (SALn), auditory network, sensorimotor network (SMn), and visual network sustain mentation. Ketamine modifies consciousness differently from other agents, producing psychedelic dreaming and no apparent interaction with the environment. The authors used functional magnetic resonance imaging to explore ketamine-induced changes in RSNs connectivity. METHODS: Fourteen healthy volunteers received stepwise intravenous infusions of ketamine up to loss of responsiveness. Because of agitation, data from six subjects were excluded from analysis. RSNs connectivity was compared between absence of ketamine (wake state [W1]), light ketamine sedation, and ketamine-induced unresponsiveness (deep sedation [S2]). RESULTS: Increasing the depth of ketamine sedation from W1 to S2 altered DMn and SALn connectivity and suppressed the anticorrelated activity between DMn and other brain regions. During S2, DMn connectivity, particularly between the medial prefrontal cortex and the remaining network (effect size ß [95% CI]: W1 = 0.20 [0.18 to 0.22]; S2 = 0.07 [0.04 to 0.09]), and DMn anticorrelated activity (e.g., right sensory cortex: W1 = -0.07 [-0.09 to -0.04]; S2 = 0.04 [0.01 to 0.06]) were broken down. SALn connectivity was nonuniformly suppressed (e.g., left parietal operculum: W1 = 0.08 [0.06 to 0.09]; S2 = 0.05 [0.02 to 0.07]). Executive control networks, auditory network, SMn, and visual network were minimally affected. CONCLUSIONS: Ketamine induces specific changes in connectivity within and between RSNs. Breakdown of frontoparietal DMn connectivity and DMn anticorrelation and sensory and SMn connectivity preservation are common to ketamine and propofol-induced alterations of consciousness.


Assuntos
Anestésicos Dissociativos/farmacologia , Encéfalo/efeitos dos fármacos , Encéfalo/diagnóstico por imagem , Estado de Consciência/efeitos dos fármacos , Ketamina/farmacologia , Imageamento por Ressonância Magnética , Adulto , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Rede Nervosa/diagnóstico por imagem , Rede Nervosa/efeitos dos fármacos , Valores de Referência , Descanso , Adulto Jovem
16.
Brain ; 138(Pt 9): 2619-31, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26117367

RESUMO

Despite advances in resting state functional magnetic resonance imaging investigations, clinicians remain with the challenge of how to implement this paradigm on an individualized basis. Here, we assessed the clinical relevance of resting state functional magnetic resonance imaging acquisitions in patients with disorders of consciousness by means of a systems-level approach. Three clinical centres collected data from 73 patients in minimally conscious state, vegetative state/unresponsive wakefulness syndrome and coma. The main analysis was performed on the data set coming from one centre (Liège) including 51 patients (26 minimally conscious state, 19 vegetative state/unresponsive wakefulness syndrome, six coma; 15 females; mean age 49 ± 18 years, range 11-87; 16 traumatic, 32 non-traumatic of which 13 anoxic, three mixed; 35 patients assessed >1 month post-insult) for whom the clinical diagnosis with the Coma Recovery Scale-Revised was congruent with positron emission tomography scanning. Group-level functional connectivity was investigated for the default mode, frontoparietal, salience, auditory, sensorimotor and visual networks using a multiple-seed correlation approach. Between-group inferential statistics and machine learning were used to identify each network's capacity to discriminate between patients in minimally conscious state and vegetative state/unresponsive wakefulness syndrome. Data collected from 22 patients scanned in two other centres (Salzburg: 10 minimally conscious state, five vegetative state/unresponsive wakefulness syndrome; New York: five minimally conscious state, one vegetative state/unresponsive wakefulness syndrome, one emerged from minimally conscious state) were used to validate the classification with the selected features. Coma Recovery Scale-Revised total scores correlated with key regions of each network reflecting their involvement in consciousness-related processes. All networks had a high discriminative capacity (>80%) for separating patients in a minimally conscious state and vegetative state/unresponsive wakefulness syndrome. Among them, the auditory network was ranked the most highly. The regions of the auditory network which were more functionally connected in patients in minimally conscious state compared to vegetative state/unresponsive wakefulness syndrome encompassed bilateral auditory and visual cortices. Connectivity values in these three regions discriminated congruently 20 of 22 independently assessed patients. Our findings point to the significance of preserved abilities for multisensory integration and top-down processing in minimal consciousness seemingly supported by auditory-visual crossmodal connectivity, and promote the clinical utility of the resting paradigm for single-patient diagnostics.


Assuntos
Encéfalo/irrigação sanguínea , Transtornos da Consciência/patologia , Vias Neurais/irrigação sanguínea , Estado Vegetativo Persistente/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Criança , Coma/patologia , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Vias Neurais/patologia , Oxigênio/sangue , Descanso , Índice de Gravidade de Doença , Adulto Jovem
17.
Brain Inj ; 30(3): 343-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26890670

RESUMO

MAIN OBJECTIVE: Disorders of consciousness (DOC; encompassing coma, vegetative state/unresponsive wakefulness syndrome (VS/UWS) and minimally conscious state minus/plus (MCS-/+)) are associated with structural brain injury. The extent of this damage remains poorly understood and merits a detailed examination using novel analysis techniques. Research design/methods and procedures: This study used voxel-based morphometry (VBM) on structural magnetic resonance imaging scans of 61 patients with DOC to examine grey and white matter injury associated with DOC, time spent in DOC, aetiology and diagnosis. MAIN OUTCOMES AND RESULTS: DOC and time spent in DOC were found to be associated with widespread structural brain injury, although the latter did not correlate strongly with injury in the right cerebral hemisphere. Traumatic, as compared to non-traumatic aetiology, was related to more injury in the brainstem, midbrain, thalamus, hypothalamus, basal forebrain, cerebellum, and posterior corpus callosum. Potential structural differences were found between VS/UWS and MCS and between MCS- and MCS+, but need further examination. CONCLUSIONS: The findings indicate that both traumatic and non-traumatic DOC are associated with widespread structural brain injury, although differences exist that could lead to aetiology-specific treatment strategies. Furthermore, the high degree of atrophy occurring after initial brain injury prompts the development and use of neuroprotective techniques to potentially increase patients' chances of recovery.


Assuntos
Lesões Encefálicas/patologia , Transtornos da Consciência/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Lesões Encefálicas/diagnóstico por imagem , Tronco Encefálico/patologia , Transtornos da Consciência/etiologia , Transtornos da Consciência/fisiopatologia , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estado Vegetativo Persistente/diagnóstico por imagem , Estado Vegetativo Persistente/patologia , Tálamo/patologia
18.
Lancet ; 384(9942): 514-22, 2014 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-24746174

RESUMO

BACKGROUND: Bedside clinical examinations can have high rates of misdiagnosis of unresponsive wakefulness syndrome (vegetative state) or minimally conscious state. The diagnostic and prognostic usefulness of neuroimaging-based approaches has not been established in a clinical setting. We did a validation study of two neuroimaging-based diagnostic methods: PET imaging and functional MRI (fMRI). METHODS: For this clinical validation study, we included patients referred to the University Hospital of Liège, Belgium, between January, 2008, and June, 2012, who were diagnosed by our unit with unresponsive wakefulness syndrome, locked-in syndrome, or minimally conscious state with traumatic or non-traumatic causes. We did repeated standardised clinical assessments with the Coma Recovery Scale-Revised (CRS-R), cerebral (18)F-fluorodeoxyglucose (FDG) PET, and fMRI during mental activation tasks. We calculated the diagnostic accuracy of both imaging methods with CRS-R diagnosis as reference. We assessed outcome after 12 months with the Glasgow Outcome Scale-Extended. FINDINGS: We included 41 patients with unresponsive wakefulness syndrome, four with locked-in syndrome, and 81 in a minimally conscious state (48=traumatic, 78=non-traumatic; 110=chronic, 16=subacute). (18)F-FDG PET had high sensitivity for identification of patients in a minimally conscious state (93%, 95% CI 85-98) and high congruence (85%, 77-90) with behavioural CRS-R scores. The active fMRI method was less sensitive at diagnosis of a minimally conscious state (45%, 30-61) and had lower overall congruence with behavioural scores (63%, 51-73) than PET imaging. (18)F-FDG PET correctly predicted outcome in 75 of 102 patients (74%, 64-81), and fMRI in 36 of 65 patients (56%, 43-67). 13 of 41 (32%) of the behaviourally unresponsive patients (ie, diagnosed as unresponsive with CRS-R) showed brain activity compatible with (minimal) consciousness (ie, activity associated with consciousness, but diminished compared with fully conscious individuals) on at least one neuroimaging test; 69% of these (9 of 13) patients subsequently recovered consciousness. INTERPRETATION: Cerebral (18)F-FDG PET could be used to complement bedside examinations and predict long-term recovery of patients with unresponsive wakefulness syndrome. Active fMRI might also be useful for differential diagnosis, but seems to be less accurate. FUNDING: The Belgian National Funds for Scientific Research (FNRS), Fonds Léon Fredericq, the European Commission, the James McDonnell Foundation, the Mind Science Foundation, the French Speaking Community Concerted Research Action, the University of Copenhagen, and the University of Liège.


Assuntos
Transtornos da Consciência/diagnóstico , Imageamento por Ressonância Magnética/métodos , Tomografia por Emissão de Pósitrons/métodos , Adolescente , Adulto , Bélgica , Transtornos da Consciência/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Prognóstico , Compostos Radiofarmacêuticos , Sensibilidade e Especificidade , Adulto Jovem
19.
Rev Prat ; 65(4): 457-9, 2015 Apr.
Artigo em Francês | MEDLINE | ID: mdl-26058178

RESUMO

Hypnosis has proved successful in a variety of clinical situations such as alleviation of acute or chronic pain and other chronic debilitating conditions (asthma-eczema). Many psychotherapists utilize imagery to facilitate the process of change, treating depression with hypnosis and integrating patient centered strategic approaches (challenge efficacy of psychotherapy). This article focuses on delivering of hypnotic interventions for pain and will provide a very short overview of core issues in the development of the cognitive neuroscience of hypnosis and conscious state.


Assuntos
Hipnose , Dor/prevenção & controle , Humanos , Medição da Dor
20.
Radiology ; 270(2): 506-16, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24471392

RESUMO

PURPOSE: To analyze white matter pathologic abnormalities by using diffusion-tensor (DT) imaging in a multicenter prospective cohort of comatose patients following cardiac arrest or traumatic brain injury (TBI). MATERIALS AND METHODS: Institutional review board approval and informed consent from proxies and control subjects were obtained. DT imaging was performed 5-57 days after insult in 49 cardiac arrest and 40 TBI patients. To control for DT imaging-processing variability, patients' values were normalized to those of 111 control subjects. Automated segmentation software calculated normalized axial diffusivity (λ1) and radial diffusivity (λ⊥) in 19 predefined white matter regions of interest (ROIs). DT imaging variables were compared by using general linear modeling, and side-to-side Pearson correlation coefficients were calculated. P values were corrected for multiple testing (Bonferroni). RESULTS: In central white matter, λ1 differed from that in control subjects in six of seven TBI ROIs and five of seven cardiac arrest ROIs (all P < .01). The λ⊥ differed from that in control subjects in all ROIs in both patient groups (P < .01). In hemispheres, λ1 was decreased compared with that in control subjects in three of 12 TBI ROIs (P < .05) and nine of 12 cardiac arrest ROIs (P < .01). The λ⊥ was increased in all TBI ROIs (P < .01) and in seven of 12 cardiac arrest ROIs (P < .05). Cerebral hemisphere λ1 was lower in cardiac arrest than in TBI in six of 12 ROIs (P < .01), while λ⊥ was higher in TBI than in cardiac arrest in eight of 12 ROIs (P < .01). Diffusivity values were symmetrically distributed in cardiac arrest (P < .001 for side-to-side correlation) but not in TBI patients. CONCLUSION: DT imaging findings are consistent with the known predominance of cerebral hemisphere axonal injury in cardiac arrest and chiefly central myelin injury in TBI. This consistency supports the validity of DT imaging for differentiating axon and myelin damage in vivo in humans.


Assuntos
Lesões Encefálicas/patologia , Imagem de Tensor de Difusão , Hipóxia-Isquemia Encefálica/patologia , Fibras Nervosas Mielinizadas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Coma/patologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
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