Publications of Athina Demertzi
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See detailPec des états de conscience altérés et du patient locked-in
Demertzi, Athina ULiege

Learning material (2021)

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See detailContentless Thinking is Associated with Whole-Brain Positive Inter-Areal Connectivity Patterns
Mortaheb, Sepehr ULiege; Van Calster, Laurens ULiege; Boulakis, Paradeisios Alexandros et al

Poster (2021, June)

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See detailMind Blanking is Associated with a Rigid Spatio-Temporal Profile in Typical Wakefulness
Mortaheb, Sepehr ULiege; Klados, Manousos; Van Calster, Laurens ULiege et al

Poster (2021, May 28)

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See detailEye movement responses to caloric vestibular irrigations reveal the contribution of voluntary processes to autonomic reflexes
Koroma, Matthieu ULiege; Delcamp, Clément; Mortaheb, Sepehr ULiege et al

Scientific conference (2021, May 28)

Can autonomic reflexes inform us about higher-order cognitive processes ? To address this issue, we studied habituation (a form of non-associative learning) of the slow, uncontrolled eye movement response ... [more ▼]

Can autonomic reflexes inform us about higher-order cognitive processes ? To address this issue, we studied habituation (a form of non-associative learning) of the slow, uncontrolled eye movement response (nystagmus) following repetitive caloric (warm water) vestibular irrigation. After a 30s irrigation trial (total trials=6), participants (n=26) either kept their gaze fixated, or let their gaze free, testing voluntary adaptations of the nystagmus response measured with electrooculography (EOG). Participants also reported the intensity of the vertigo that they experienced after each irrigation. We found that the amplitude of the nystagmus response decreased over repetitive irrigations, revealing a clear habituation (repeated measures ANOVA with participants as random factor, F(5)=-18.8, p<0.001). We further showed that the amplitude of nystagmus is reduced after the gaze fixation condition compared to the freely moving gaze (interaction between irrigation and fixation, F(5,1)=5.1, p=0.025). Finally, by relying on a model comparison approach, we demonstrate that the oculomotor response holds partial information on the decrease of the vertigo experienced over successive irrigations, suggesting a bi-directional interaction between central and autonomic processes (Likelihood-ratio chi-squared test between mixed-models predicting vertigo response and including or excluding the duration of nystagmus, 𝜒2(12)=11.96, p=0.013). These findings suggest that reflexes carry partial information about voluntary processes. From the interoceptive active inference framework, these results might be relevant for evidencing signs of sentience when this cannot be communicated overtly. [less ▲]

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See detailContentless thinking is associated with overall positive inter-areal connectivity configurations
Mortaheb, Sepehr ULiege; Van Calster, Laurens ULiege; Boulakis, Paradeisios Alexandros et al

Poster (2021, March)

During spontaneous mentation, our minds are occupied with different contents, including periods of contentless thinking (mind blanking). As the frequency of mind blanking events is non-negligible, an ... [more ▼]

During spontaneous mentation, our minds are occupied with different contents, including periods of contentless thinking (mind blanking). As the frequency of mind blanking events is non-negligible, an emerging question is whether this mental state constitutes an accidental blip or rather a default function of our ongoing mental flow. Using fMRI experience-sampling in 36 typical subjects during which mind blanking could be chosen among various mental states, we show that mind blanking (MB) is less frequent (6%) compared to sensory-oriented (Sens, 19%), stimulus-dependent (SDep, 31%), and stimulus-independent thoughts (SInd, 43%), distributed equally across time (Chi-square uniformity test, χ2(9)=6.18, p=0.72). The probability of reporting mind blanking is low but equal when departing from the other states (Markov chain transition probability=0.06), suggesting that this state is not driven by specific mental content; also, the low probability (0.04) to re-enter mind-blanking indicates that contentless reports may be less anchoring as compared to content-oriented thinking. FMRI phase-based coherence showed that a recurrent brain pattern of overall positive functional connectivity was closer to mind blanking reports (in the sense of Euclidean distance) compared to other mental states (p=0.035 for MB vs. Sens and p<0.001 for MB vs. SDep and MB vs. SInd, linear mixed effect model and posthoc Tukey's test). This indicates that mind blanking is a default mental state supported by an over-connected brain configuration. Such overall positive connectivity can reflect a distributed fight of multiple local units to enter into the supervisory attentional system, which may hinder reportable mental content formation. [less ▲]

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See detailEthics of life-sustaining treatment in locked-in syndrome: A Chinese survey
Yan, Yifan; Demertzi, Athina ULiege; Xia, Yinyan et al

in Annals of Physical and Rehabilitation Medicine (2020)

BACKGROUND: Locked-in syndrome (LIS) characterizes individuals who have experienced pontine lesions, who have limited motor output but with preserved cognitive abilities. Despite their severe physical ... [more ▼]

BACKGROUND: Locked-in syndrome (LIS) characterizes individuals who have experienced pontine lesions, who have limited motor output but with preserved cognitive abilities. Despite their severe physical impairment, individuals with LIS self-profess a higher quality of life than generally expected. Such third-person expectations about LIS are shaped by personal and cultural factors in western countries. OBJECTIVE: We sought to investigate whether such opinions are further influenced by the cultural background in East Asia. We surveyed attitudes about the ethics of life-sustaining treatment in LIS in a cohort of medical and non-medical Chinese participants. RESULTS: The final study sample included 1545 respondents: medical professionals (n=597, 39%), neurologists (n=303, 20%), legal professionals (n=276, 18%) and other professionals (n=369, 24%), including 180 family members of individuals with LIS. Most of the participants (70%), especially neurologists, thought that life-sustaining treatment could not be stopped in individuals with LIS. It might be unnecessary to withdraw life-sustaining treatment, because the condition involved is not terminal and irreversible, and physical treatment can be beneficial for the patient. A significant proportion (59%) of respondents would like to be kept alive if they were in that condition; however, older people thought the opposite. Families experience the stress of caring for individuals with LIS. The mean (SD) quality of life score for relatives was 0.73 (2.889) (on a -5,+5 scale), which was significantly lower than that of non-relatives, 1.75 (1.969) (P<0.001). CONCLUSIONS: Differences in opinions about end of life in LIS are affected by personal characteristics. The current survey did not identify a dissociation between personal preferences and general opinions, potentially because of a social uniformity in China where individualism is less pronounced. Future open-ended surveys could identify specific needs of caregivers so that strategic interventions to reduce ethical debasement are designed. [less ▲]

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See detailComplete hemispherotomy leads to lateralized functional organization and lower level of consciousness in the isolated hemisphere
Blauwblomme, Thomas; Demertzi, Athina ULiege; Tacchela, Jean‐Marc et al

in Epilepsia Open (2020)

Objective To quantify whole‐brain functional organization after complete hemispherotomy, characterizing unexplored plasticity pathways and the conscious level of the dissected hemispheres. Methods ... [more ▼]

Objective To quantify whole‐brain functional organization after complete hemispherotomy, characterizing unexplored plasticity pathways and the conscious level of the dissected hemispheres. Methods Evaluation with multimodal magnetic resonance imaging in two pediatric patients undergoing right hemispherotomy including complete callosotomy with a perithalamic section. Regional cerebral blood flow and fMRI network connectivity assessed the functional integrity of both hemispheres after surgery. The level of consciousness was tested by means of a support vector machine classifier which compared the intrinsic organization of the dissected hemispheres with those of patients suffering from disorders of consciousness. Results After hemispherotomy, both patients showed typical daily functionality. We found no interhemispheric transfer of functional connectivity in either patient as predicted by the operation. The healthy left hemispheres displayed focal blood hyperperfusion in motor and limbic areas, with preserved network‐level organization. Unexpectedly, the disconnected right hemispheres showed sustained network organization despite low regional cerebral blood flow. Subcortically, functional connectivity was increased in the left thalamo‐cortical loop and between the cerebelli. One patient further showed unusual ipsilateral right cerebello‐cortical connectivity, which was explained by the mediation of the vascular system. The healthy left hemisphere had higher probability to be classified as in a minimally conscious state compared to the isolated right hemisphere. Significance Complete hemispherotomy leads to a lateralized whole‐brain organization, with the remaining hemisphere claiming most of the brain's energetic reserves supported by subcortical structures. Our results further underline the contribution of nonneuronal vascular signals on contralateral connectivity, shedding light on the nature of network organization in the isolated tissue. The disconnected hemisphere is characterized by a level of consciousness which is necessary but insufficient for conscious processing, paving the way for more specific inquiries about its role in awareness in the absence of behavioral output. [less ▲]

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See detailWhen consciousness fades away: Lessons from noncommunicating states
Demertzi, Athina ULiege

Speech/Talk (2020)

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See detailThe neural basis of Consciousness
Demertzi, Athina ULiege

Speech/Talk (2020)

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See detailTime-Delay Latency of Resting-State Blood Oxygen Level-Dependent Signal Related to the Level of Consciousness in Patients with Severe Consciousness Impairment.
Rudas, Jorge; Martinez, Darwin; Castellanos, Gabriel et al

in Brain Connectivity (2020), 10(2), 83-94

Recent evidence on resting-state functional magnetic resonance imaging (rs-fMRI) suggests that healthy human brains have a temporal organization represented in a widely complex time-delay structure. This ... [more ▼]

Recent evidence on resting-state functional magnetic resonance imaging (rs-fMRI) suggests that healthy human brains have a temporal organization represented in a widely complex time-delay structure. This structure seems to underlie brain communication flow, integration/propagation of brain activity, as well as information processing. Therefore, it is probably linked to the emergence of highly coordinated complex brain phenomena, such as consciousness. Nevertheless, possible changes in this structure during an altered state of consciousness remain poorly investigated. In this work, we hypothesized that due to a disruption in high-order functions and alterations of the brain communication flow, patients with disorders of consciousness (DOC) might exhibit changes in their time-delay structure of spontaneous brain activity. We explored this hypothesis by comparing the time-delay projections from fMRI resting-state data acquired in resting state from 48 patients with DOC and 27 healthy controls (HC) subjects. Results suggest that time-delay structure modifies for patients with DOC conditions when compared with HC. Specifically, the average value and the directionality of latency inside the midcingulate cortex (mCC) shift with the level of consciousness. In particular, positive values of latency inside the mCC relate to preserved states of consciousness, whereas negative values change proportionally with the level of consciousness in patients with DOC. These results suggest that the mCC may play a critical role as an integrator of brain activity in HC subjects, but this role vanishes in an altered state of consciousness. [less ▲]

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See detailPerturbations in dynamical models of whole-brain activity dissociate between the level and stability of consciousness
Sanz Perl; Pallavicini, Carla; Pérez Ipiña, Ignacio et al

E-print/Working paper (2020)

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See detailQuantifying conscious states by means of self-initiated brain activity
Demertzi, Athina ULiege

Conference (2019, November 01)

Consciousness is seemingly lost and recovered every day, from the moment we fall asleep until we wake up. Although these departures from wakefulness bring about different changes in brain function ... [more ▼]

Consciousness is seemingly lost and recovered every day, from the moment we fall asleep until we wake up. Although these departures from wakefulness bring about different changes in brain function, behavior, and neurochemistry, they all lead to lack of reported subjective experience. Here, I will show how intrinsic brain activity has been characterized in different states of unconsciousness, such as pharmacologically-induced anesthesia in humans and in noncommunicating states after severe brain injury. These investigations indicate that during unconscious states, cortical long-range correlations are disrupted in both space and time, anticorrelated cortical interactions disappear, and that temporal dynamics are limited to describe specific patterns which are dominated by rigid functional configurations tied to the anatomical connectivity. These data shed light on ongoing brain dynamics in health and disease and pave the way for specific interventions to potentially restore consciousness when it seems lost. [less ▲]

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See detailHypnosis for cingulate-mediated analgesia and disease treatment
Trujillo-Rodriguez, Diana ULiege; FAYMONVILLE, Marie-Elisabeth ULiege; VANHAUDENHUYSE, Audrey ULiege et al

in Vogt, Brendt A (Ed.) Cingulate Cortex. Handbook of Clinical Neurology (3rd series) (2019)

Hypnosis is a technique that induces changes in perceptual experience through response to specific suggestions. By means of functional neuroimaging, a large body of clinical and experimental studies has ... [more ▼]

Hypnosis is a technique that induces changes in perceptual experience through response to specific suggestions. By means of functional neuroimaging, a large body of clinical and experimental studies has shown that hypnotic processes modify internal (self-awareness) as well as external (environmental awareness) brain networks. Objective quantifications of this kind permit the characterization of cerebral changes after hypnotic induction and its uses in the clinical setting. Hypnosedation is one such application, as it combines hypnosis with local anesthesia in patients undergoing surgery. The power of this technique lies in the avoidance of general anesthesia and its potential complications that emerge during and after surgery. Hypnosedation is associated with improved intraoperative comfort and reduced perioperative anxiety and pain. It ensures a faster recovery of the patient and diminishes the intraoperative requirements for sedative or analgesic drugs. Mechanisms underlying the modulation of pain perception under hypnotic conditions involve cortical and subcortical areas, mainly the anterior cingulate and prefrontal cortices as well as the basal ganglia and thalami. In that respect, hypnosis-induced analgesia is an effective and highly cost-effective alternative to sedation during surgery and symptom management. [less ▲]

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See detailQuantifying states of consciousness by means of intrinsic brain connectivity
Demertzi, Athina ULiege

Speech/Talk (2019)

Consciousness is seemingly lost and recovered every day, from the moment we fall asleep until we wake up. Although these departures from wakefulness bring about different changes in brain function ... [more ▼]

Consciousness is seemingly lost and recovered every day, from the moment we fall asleep until we wake up. Although these departures from wakefulness bring about different changes in brain function, behavior, and neurochemistry, they all lead to lack of reported subjective experience. Here, I will show how ongoing brain activity has been characterized in different states of unconsciousness, such as pharmacologically-induced anesthesia in humans and in noncommunicating states after severe brain injury. By and large, these investigations indicate that during unconscious states cortical long-range correlations are disrupted in both space and time, anticorrelated cortical interactions disappear, and that temporal dynamics are limited to describe specific patterns which are dominated by rigid functional configurations tied to the anatomical connectivity [less ▲]

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See detailGeneral Anesthesia: A Probe to Explore Consciousness
BONHOMME, Vincent ULiege; STAQUET, Cécile ULiege; Montupil, Javier ULiege et al

in Frontiers in Systems Neuroscience (2019)

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See detailReview: Quantifying conscious level by means of intrinsic brain connectivity
Demertzi, Athina ULiege

Conference (2019, June 24)

Consciousness is seemingly lost and recovered every day, from the moment we fall asleep until we wake up. Although these departures from wakefulness bring about different changes in brain function ... [more ▼]

Consciousness is seemingly lost and recovered every day, from the moment we fall asleep until we wake up. Although these departures from wakefulness bring about different changes in brain function, behavior, and neurochemistry, they all lead to lack of reported subjective experience. Here, I will show how the temporal dynamics of ongoing brain activity have characterized different states of unconsciousness, such as sleep, pharmacologically-induced anesthesia in humans and animals, and in noncommunicating states following to brain injury. By and large, these investigations indicate that during unconscious states cortical long-range correlations are disrupted in both space and time, anticorrelated cortical interactions disappear, and the dynamic explorations are limited to specific patterns which are dominated by rigid functional configurations tied to the anatomical connectivity. [less ▲]

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See detailTutorial: Resting state fMRI as a means to assess the consciousness after severe brain injury
Demertzi, Athina ULiege

Conference (2019, June 24)

Consciousness is a complex construct with no universal definition. Especially in pathological conditions how can one reliably observe and measure it? Behavioural evaluation is not straightforward, despite ... [more ▼]

Consciousness is a complex construct with no universal definition. Especially in pathological conditions how can one reliably observe and measure it? Behavioural evaluation is not straightforward, despite systematic assessments, due to patients’ physical and cognitive condition. Yet, the diagnosis of disorders of consciousness has been notably facilitated by means of technological modalities. Here, we will see how systems-level functional neuroimaging has assisted clinical evaluation, how it can potentially be informative of clinical outcome, and what these findings teach us about typical conscious states. As this type of research touches upon philosophical and ethical issues, we will discuss the emerging neuroethical concerns stemming from the research of this challenging population. [less ▲]

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See detailFunctional reorganization after surgical hemispherotomy for intractable epilepsy
Demertzi, Athina ULiege; Blauwblomme, Thomas; Tacchela, Jean-Marc et al

Poster (2019, June 12)

Introduction: Epilepsy is a chronic neurological condition characterized by seizures that may lead to transient loss of consciousness (1). Hemispherotomy is a surgical procedure which isolates the ... [more ▼]

Introduction: Epilepsy is a chronic neurological condition characterized by seizures that may lead to transient loss of consciousness (1). Hemispherotomy is a surgical procedure which isolates the affected hemisphere, hence leading to seizure freedom. Despite acceptable neurological outcome, cerebral functional reorganization especially of the isolated hemisphere remains debatable. We aimed at exploring plasticity changes after hemispherotomy. We expected no cortical inter-hemispheric transfer of functional connectivity as a result of the structural disconnection between the two hemispheres. We further hypothesized that plasticity would involve cerebellopontino-thalamocortical routes involving the remaining functional hemisphere. Methods: Patients showed drug-resistant lesional epilepsy associated with Rasmussen encephalitis and hemimegalencephaly. They were operated by a midline vertical hemispherotomy (2): complete callosotomy was performed, allowing access to the lateral ventricles. Perithalamic section of the white matter between the frontal and temporal horn disrupted the internal capsule,  mbria, anterior commissure, but left the major intra-hemispheric bundles (superior and inferior longitudinal fasciculi, uncinated fasciculus, cingulum, external capsule) untouched. With this procedure the affected right hemisphere was isolated. MRI was performed 39m after surgery for patient1 (P1) and 31m after surgery for patient 2 (P2). Pseudo-Continuous Arti cial Spin Labelling (ASL) and 300 functional MRI volumes during resting condition were acquired on a GE Sigma 1.5T scanner. Age- and gender-matched control data were used from the National Database for Autism Research (NDAR) (http://ndar.nih.gov). ASL analysis included segmentation, brain extraction, normalization to a 7y-old brain Atlas obtained with Template-OMatic Toolbox, coregistration, realignment, normalization using the deformation  elds obtained during the T1 normalization, and smoothing (10 mm isotropic filter).FMRI analysis included slice-time correction, realignment, segmentation of structural data, normalization of functional and structural data into standard MNI space, smoothing (6mm FWHM) and denoising (cCompCor, regression of motion paramaters, temporal filtering 0.008- 0.09Hz). Functional connectivity was performed using patient-specic spherical regions of interest at the cortical subcortical level. Results: In both patients, the disconnected right hemisphere (RH) showed general hypo-perfusion, and the preserved left hemisphere (LH) had hyper-perfusion mainly in motor and temporal areas. Neither patient showed inter-hemispheric transfer of functional connectivity. Thalamo-cortical connectivity was preserved only in the LHs. Intercerebellar connectivity was present but cerebello-cortical crossings were preserved only in the LHs. P2 further showed right-sided ipsilateral cerebello-cortical connectivity, which was mediated by the effect of the vascular system. Both patients' brain showed preserved yet lateralized network-level organization. Conclusions: After hemispherotomy the two hemispheres function in a disconnected manner. The isolated brain is resilient to support intrinsic functional connectivity which is mediated, yet not fully explained, by the effect of vascularization. These data are relevant for a better comprehension of functional organization after neurosurgery and raise inquiries about the cognitive role of the isolated right hemisphere. [less ▲]

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See detailJoint temporo-occipital connectivity re ects higher-order function associated with conscious states
Antonopoulos, Georgios ULiege; Kupers, Ron; Cohen, Laurent et al

Poster (2019, June 10)

Introduction: We have previously used machine learning to separate minimally conscious from unconscious patients based on network-level resting state fMRI connectivity (Demertzi et al., 2015). By means of ... [more ▼]

Introduction: We have previously used machine learning to separate minimally conscious from unconscious patients based on network-level resting state fMRI connectivity (Demertzi et al., 2015). By means of a Support Vector Machine (SVM) classifier and using connectivity values extracted from the "auditory network" as features, we identified 20/22 patients leading to an accuracy of 91% in differentiating the two clinical populations when validated on an independent dataset. The features of the "auditory network" encompassed temporal and occipital regions, raising the question whether the classifier captures merely sensory information (i.e. auditory, visual) or higher-order cortical organization pertaining to conscious conditions. To that aim, we performed generalization trials on data collected from congenitally deaf and congenitally blind patients with preserved global states of consciousness. We hypothesized that if the classifier captures global states of consciousness, the new tested subjects would belong to the class of the minimally conscious patients. Methods: The training dataset included 45 patients with disorders of consciousness (26 MCS, 19 UWS). The generalisation dataset included nine congenitally blind and eight congenitally deaf subjects. Functional images (300 for the training and 280 for the generalisation dataset) and a structural image were acquired on 3T MRI systems. Preprocessing of functional images included slice-time correction, realignment, segmentation, normalisation, and smoothing (6mm FWHM). Noise reduction included detection and regression of motion outliers (ART toolbox), anatomical component-based correction, regression of motion parameters, and band-pass filtering (0.008-0.09Hz). Structural images were reoriented, spatially normalized to MNI space, segmented and smoothed (6mm FWHM). For all preprocessing steps we used SPM8 (Ashburner et al, 2005). Seven spherical regions were used as seeds (Maudoux et al., 2012) from which averaged time-series were calculated to estimate whole brain correlation r-maps. R-maps were then converted to normally distributed Fisher's z transformed correlation maps. One-sample t-test was ordered to estimate seed-tovoxel whole brain connectivity. Three connectivity values per subject were extracted using binary masks, which were calculated on patients with disorders of consciousness and which encompassed bilateral temporal and occipital areas. A linear SVM with default regularization parameter C=1 was trained on the data (45X3 features) from patients with disorders of consciousness. Results: Out of the nine congenitally blind subjects, one was placed in the class of unconscious patients. Out of the 8 congenitally deaf subjects, one was placed in the class of unconscious patients. Conclusions: Our results indicate that joint temporo-occipital functional connectivity exceeds mere sensory perception and it reflects higher-order functional organisation indicative of preserved conscious states. These findings assist to better comprehend aspects of conscious processes, which are further informative to evaluate covert cognition in noncommunicating conditions. [less ▲]

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See detailBrain functional network segregation and integration in patients with disorders of consciousness
Panda, Rajanikant ULiege; Annen, Jitka ULiege; Gosseries, Olivia ULiege et al

Conference (2019, June 10)

Introduction: The brain regulates information flow by balancing integration and segregation of networks to facilitate flexible cognition and behavior. However, it is unclear how this mechanism manifests ... [more ▼]

Introduction: The brain regulates information flow by balancing integration and segregation of networks to facilitate flexible cognition and behavior. However, it is unclear how this mechanism manifests during loss of consciousness [1-3]. In this study, we studied brain network segregation and integration using resting state functional magnetic resonance imaging (fMRI) data to assess brain networks in patients with disorders of consciousness. Methods: Fifty-four patients with disorders of consciousness (24 unresponsive wakefulness syndrome (UWS) (M:F=16:8; mean age= 45±13), 30 minimally conscious state (MCS) (M:F=23:7; mean age= 36±14) and 30 age- and gender-matched healthy controls underwent fMRI. The resting-state MRI data were acquired during wakefulness with eyes closed using a 3 Tesla MRI scanner. Additionally a T1-weighted, structural imaging was performed for anatomical coregistration. First, the fMRI data were pre-processed for realignment, co-registration, segmentation, normalization, head motion regressed out and 0.01-0.1Hz band pass filtered. Data were then parcellated in 256 brain regions (ROIs) using Shen functional atlas from [4]. The connectivity matrix was computed using Pearson correlation. Graph theory connectivity was carried out to measure brain network topological properties in terms of network segregation and integration by computing binarized undirected connectivity matrix. Normalized clustering coefficients were computed as measures of network segregation while normalized participation coefficients were computed as measures of network integration [3]. Through integrated nodal graph measures, individual networks (such as default mode, frontoparietal, auditory, salience, subcortical and cerebellum networks) were also computed to study which networks were predominantly affected [3]. To enable comparison of network properties across groups, we used sparsity-based threshold (S) to avoid spurious results. To prevent biases associated with a single threshold, we determined a range of sparsity (0.06 ≤ S ≤ 0.5, with an increment of 0.025), which avoids excess network fragmentation at sparser thresholds. The between group differences for global (i.e., whole brain) and individual networks were computed with unpaired t-test with FDR correction for multiple comparison [5-6]. Finally the network segregation and integration mean values were correlated with Coma Recovery Scale-Revised (CRS-R) modified score [7]. Results: Patients in UWS had decreased participation coefficients (network integration) compared to those in MCS (effect size= -0.44, p<0.0001) and controls (effect size= -0.63, p<0.0001). Patients in MCS had significant decreased participation coefficients compared to controls (effect size= -0.37, p<0.001). On the other hand, patients in UWS had significant increased clustering coefficient (network segregation) compared to those in MCS (effect size= 0.39, p= <0.001) and controls (effect size= 0.63, p<0.0001). Patients in MCS had significant increased clustering coefficients compared to controls (effect size= 0.03, p<0.01). This decreased participation coefficient and increased clustering coefficient were noted predominantly observed in the frontoparietal and subcortical networks. Conclusions: Patients with disorders of consciousness present decreased in network integration and increased in network segregation. Notably, fragmentation of network integration is observed in patients in unaware patients (UWS), which indicates impaired information flow in the brain modules, especially in the frontoparietal and subcortical networks. This introduces a potential measure to classify patients with disorders of consciousness, which could ultimately be used for clinical diagnosis. Reference: 1. Fukushima, M., (2018). Structure–function relationships during segregated and integrated network states of human brain functional connectivity. Brain Structure and Function, 223(3), 1091-1106. 2. Deco, G., (2015). Rethinking segregation and integration: contributions of whole-brain modelling. Nature Reviews Neuroscience, 16(7), 430. 3. Keerativittayayut, R., (2018). Large-scale network integration in the human brain tracks temporal uctuations in memory encoding performance. eLife, 7, e32696. 4. Finn, E. S., (2015). Functional connectome ngerprinting: identifying individuals using patterns of brain connectivity. Nature neuroscience, 18(11), 1664. 5. Holla, B., (2017). Disrupted resting brain graph measures in individuals at high risk for alcoholism. Psychiatry Research: Neuroimaging, 265, 54-64. 6. Chennu, S., (2017). Brain networks predict metabolism, diagnosis and prognosis at the bedside in disorders of consciousness. Brain, 140(8), 2120-2132. 7. Demertzi, A., (2015). Intrinsic functional connectivity differentiates minimally conscious from unresponsive patients. Brain, 138(9), 2619-2631. [less ▲]

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