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 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 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 detailBOLD power spectral density differentiates patients with pathological consciousness
Alcauter, Sarael; Carrière, Manon ULiege; Raimondo, Federico ULiege et al

Poster (2019, June 10)

Introduction: Functional connectivity has been successfully used to discriminate non-sedated patients with disorders of consciousness (Demertzi et al., 2015). However, on clinical demand, patients are ... [more ▼]

Introduction: Functional connectivity has been successfully used to discriminate non-sedated patients with disorders of consciousness (Demertzi et al., 2015). However, on clinical demand, patients are evaluated under sedation to restrict motion, which considerably limits the classification of patients based on functional connectivity. It has been previously shown that changes of the frequency properties of spontaneous BOLD signal are of cognitive relevance even in sleeping neonates (Alcauter et al., 2015). We therefore aimed at exploring the automatic discrimination of sedated patients in the clinical entities of minimally consciousness state (MCS) and unresponsive wakefulness syndrome (UWS), based on the frequency profile of the BOLD signal. Methods: Forty-four patients with MCS (n=26) or VS/UWS (n=18), based on the Coma Recovery Scale-Revised (CRS-R), were scanned on a 3T MRI scanner. Images of the whole brain were acquired with BOLD-sensitive sequences (300 volumes, TR=2s, TE=30ms, voxel size=3x3x3 mm3) and a T1 (TR=2.3s, TE=2.47ms, voxel size = 1x1x1.2 mm3). Sedative agents (propofol, sevoflurane, or a combination of both) were administered using the minimum necessary dose. 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, and regression of motion parameters, no temrporal filtering was applied. The average power density between 0.01 and 0.1 Hz (classic frequency band for resting state analyses) was estimated and divided by the total power density, for each voxel. Supervised classification of patients in MCS or UWS was explored with Support Vector Machine classifiier using stratified 5-fold cross-validation. The clusters with significant differences between groups (p<0.005, uncorrected; cluster size > 10 voxels) in the training sets were selected as features. The 5-fold validation was repeated 20 times to estimate the variability of the classification accuracies and the frequency of each voxel being selected as a relevant feature. Results:The average classification accuracy was 79%±5 (SD), with average sensitivity 76%±10, and specificity 81%±9. The most frequently selected regions as features included the superior parietal lobule (Frequency: 100%; MNI x, y, z (mm): -26, -50, 64), putamen (97%; -30, -6, -8), occipital fusiform gyrus (92%; -34, -70, -20), occipital pole (65%; 22, -98, 16), angular gyrus (54%; -60, -58, 32). Conclusions: The power spectral density of the spontaneous BOLD signal under anesthesia allowed to classify individual patients with MCS and UWS with 79% accuracy. The most frequent selected features included association areas in the parietal and occipital lobes and the putamen. Further validation with independent cohorts is needed to generalize the current findings. Taken together, the use of power spectral density may represent an alternative to functional connectivity to classify patients with consciousness disorders under anesthesia, therefore capturing properties of conscious function beyond reportability. [less ▲]

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See detailHuman consciousness is supported by dynamic complex patterns of brain signal coordination
Demertzi, Athina ULiege; Tagliazucchi, Enzo; Dehaene, S et al

in Science Advances (2019), 5(2), 7603

Adopting the framework of brain dynamics as a cornerstone of human consciousness, we determined whether dynamic signal coordination provides specific and generalizable patterns pertaining to conscious and ... [more ▼]

Adopting the framework of brain dynamics as a cornerstone of human consciousness, we determined whether dynamic signal coordination provides specific and generalizable patterns pertaining to conscious and unconscious states after brain damage. A dynamic pattern of coordinated and anticoordinated functional magnetic resonance imaging signals characterized healthy individuals and minimally conscious patients. The brains of unresponsive patients showed primarily a pattern of low interareal phase coherence mainly mediated by structural connectivity, and had smaller chances to transition between patterns. The complex pattern was further corroborated in patients with covert cognition, who could perform neuroimaging mental imagery tasks, validating this pattern’s implication in consciousness. Anesthesia increased the probability of the less complex pattern to equal levels, validating its implication in unconsciousness. Our results establish that consciousness rests on the brain’s ability to sustain rich brain dynamics and pave the way for determining specific and generalizable fingerprints of conscious and unconscious states. [less ▲]

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See detailNeural correlates of modified subjective state of consciousness induced by hypnosis using EEG-connectivity approach
Panda, Rajanikant ULiege; Gosseries, Olivia ULiege; VANHAUDENHUYSE, Audrey ULiege et al

Poster (2019, January 17)

Introduction: Hypnotic state has been shown to be of clinical utility, however its neural mechanisms still remain unclear [1]. This study investigates the neural basis of hypnosis using resting state EEG ... [more ▼]

Introduction: Hypnotic state has been shown to be of clinical utility, however its neural mechanisms still remain unclear [1]. This study investigates the neural basis of hypnosis using resting state EEG connectivity measurements. Methods: Ten healthy subjects (7 females, mean age 24±3years) underwent high density EEG recordings in both eye close awake resting state and hypnosis state. The hypnotic state instruction involved a 3-min induction procedure with muscle relaxation and eye fixation. After preprocessing EEG data, both hypothesis and data driven analysis were conducted using connectivity approach. Classical power spectral analysis was performed for delta (1-4Hz), theta (4.1-8Hz), alpha (8.1-12Hz), beta1 (12.1-20Hz) and beta2 (20.1-30Hz) frequency bands. Connectivity between every pair of electrodes was assessed using weighted Phase Lag Index. Hypothesis-based connectivity was computed for frontal, parietal and midline regions [2]. Data-driven graph theory connectivity was carried out to measure brain connectivity network properties and altered hub regions [3]. Results and Discussion: During hypnosis, increased spectral power was observed in delta and decreases were noted in the alpha and beta bands. From hypothesis based connectivity analysis, we observed an increased frontal interhemispheric connectivity in delta and left frontal to right parietal in theta band. Decreased connectivity was found both for alpha and beta bands in midline (upper central with lower central), right frontal with ‘right parietal and upper central’. Graph theory measures showed differences between hypnotic state and resting state both at the global and local level. Through integrated nodal clustering coefficient, we found increased frontoparietal connectivity in delta and theta bands and decreased bilateral frontal and parietal connectivity in alpha and beta-2 frequency bands. During hypnosis, we found increased connectivity in the lower frequency range (i.e., delta) and decreases at higher frequencies (i.e., beta) when considering frontal and parietal regions. These oscillations seems to characterise modified subjective state of consciousness induced by hypnosis, possibly reflecting states of efficient cognitive-processing and positive-emotional experiences. [less ▲]

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See detailCan subjective ratings of absorption, dissociation, and time perception during “neutral hypnosis” predict hypnotizability?: An exploratory study.
VANHAUDENHUYSE, Audrey ULiege; LEDOUX, Didier ULiege; Gosseries, Olivia ULiege et al

in International Journal of Clinical and Experimental Hypnosis (2019), 67(1), 28-38

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