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1.
Soc Sci Med ; 351 Suppl 1: 116291, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38825383

ABSTRACT

The purpose of this article is to delineate the nature of the colonial mindset, which perpetuates gendered settler colonial structures of historical oppression in research and practice. By connecting a critical consciousness and living in alignment with agility (AWA), this work explicates pathways from gendered complicity to embodying praxis-or becoming gender AWAke. This article begins by describing the nature of the colonial mindset. Second, I critically examine the dominant discourse institutionalized by Western psychology. Third, I introduce the FHORT and critically analyze how the colonial mindset has affected and driven violence against Indigenous women. Examining how settler colonial structural sexism in its heteropatriarchal and heteropaternalistic forms has become imposed upon the lives of Indigenous women and gender-expansive peoples exposes subjugated knowledges; it provides an empirical scaffolding for people to become critically conscious of dominant gender norms that apply to people, institutions, and society more broadly. Finally, I propose living AWAke for personal and collective liberation.


Subject(s)
Colonialism , Humans , Sexism/psychology , Female , Gender Identity , Indigenous Peoples/psychology , Consciousness
2.
CNS Neurosci Ther ; 30(6): e14782, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38828651

ABSTRACT

BACKGROUND: The thalamus system plays critical roles in the regulation of reversible unconsciousness induced by general anesthetics, especially the arousal stage of general anesthesia (GA). But the function of thalamus in GA-induced loss of consciousness (LOC) is little known. The thalamic reticular nucleus (TRN) is the only GABAergic neurons-composed nucleus in the thalamus, which is composed of parvalbumin (PV) and somatostatin (SST)-expressing GABAergic neurons. The anterior sector of TRN (aTRN) is indicated to participate in the induction of anesthesia, but the roles remain unclear. This study aimed to reveal the role of the aTRN in propofol and isoflurane anesthesia. METHODS: We first set up c-Fos straining to monitor the activity variation of aTRNPV and aTRNSST neurons during propofol and isoflurane anesthesia. Subsequently, optogenetic tools were utilized to activate aTRNPV and aTRNSST neurons to elucidate the roles of aTRNPV and aTRNSST neurons in propofol and isoflurane anesthesia. Electroencephalogram (EEG) recordings and behavioral tests were recorded and analyzed. Lastly, chemogenetic activation of the aTRNPV neurons was applied to confirm the function of the aTRN neurons in propofol and isoflurane anesthesia. RESULTS: c-Fos straining showed that both aTRNPV and aTRNSST neurons are activated during the LOC period of propofol and isoflurane anesthesia. Optogenetic activation of aTRNPV and aTRNSST neurons promoted isoflurane induction and delayed the recovery of consciousness (ROC) after propofol and isoflurane anesthesia, meanwhile chemogenetic activation of the aTRNPV neurons displayed the similar effects. Moreover, optogenetic and chemogenetic activation of the aTRN neurons resulted in the accumulated burst suppression ratio (BSR) during propofol and isoflurane GA, although they represented different effects on the power distribution of EEG frequency. CONCLUSION: Our findings reveal that the aTRN GABAergic neurons play a critical role in promoting the induction of propofol- and isoflurane-mediated GA.


Subject(s)
Anesthesia, General , Consciousness , GABAergic Neurons , Isoflurane , Propofol , Propofol/pharmacology , Isoflurane/pharmacology , Animals , GABAergic Neurons/drug effects , GABAergic Neurons/physiology , Mice , Consciousness/drug effects , Consciousness/physiology , Male , Electroencephalography , Anesthetics, Inhalation/pharmacology , Anterior Thalamic Nuclei/drug effects , Anterior Thalamic Nuclei/physiology , Mice, Inbred C57BL , Mice, Transgenic , Anesthetics, Intravenous/pharmacology , Proto-Oncogene Proteins c-fos/metabolism , Optogenetics
3.
Neuron ; 112(10): 1524-1526, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38754370

ABSTRACT

In this talk with Neuron, Christof Koch, a physicist and neuroscientist, advocates for a pragmatic program to track the footprints of consciousness in the brain and for team science, explains the recent pseudo-controversy regarding integrated information theory of consciousness, and speaks about the joy of exploring the mysteries around us.


Subject(s)
Consciousness , Neurosciences , Humans , Consciousness/physiology , History, 20th Century , Brain/physiology , History, 21st Century
4.
Neuron ; 112(10): 1519, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38754368
5.
Neuron ; 112(10): 1527-1530, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38754371

ABSTRACT

Stanislas Dehaene is a cognitive neuroscientist elucidating the biological mechanisms that give rise to human perception and cognition. In a conversation with Neuron, he talks about his ongoing interest in consciousness research, the role of theory in neuroscience, and his current work on education and the science of learning.


Subject(s)
Consciousness , Humans , History, 21st Century , Consciousness/physiology , History, 20th Century , Neurosciences/history , Learning/physiology , Cognitive Neuroscience/history
6.
Neuron ; 112(10): 1595-1610, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38754372

ABSTRACT

Recovery of consciousness after coma remains one of the most challenging areas for accurate diagnosis and effective therapeutic engagement in the clinical neurosciences. Recovery depends on preservation of neuronal integrity and evolving changes in network function that re-establish environmental responsiveness. It typically occurs in defined steps: it begins with eye opening and unresponsiveness in a vegetative state, then limited recovery of responsiveness characterizes the minimally conscious state, and this is followed by recovery of reliable communication. This review considers several points for novel interventions, for example, in persons with cognitive motor dissociation in whom a hidden cognitive reserve is revealed. Circuit mechanisms underlying restoration of behavioral responsiveness and communication are discussed. An emerging theme is the possibility to rescue latent capacities in partially damaged human networks across time. These opportunities should be exploited for therapeutic engagement to achieve individualized solutions for restoration of communication and environmental interaction across varying levels of recovery.


Subject(s)
Coma , Recovery of Function , Humans , Coma/physiopathology , Coma/therapy , Recovery of Function/physiology , Consciousness/physiology , Persistent Vegetative State/physiopathology , Persistent Vegetative State/rehabilitation
7.
Neuron ; 112(10): 1520-1523, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38754369

ABSTRACT

Conscious experiences in infants remain poorly understood. In this NeuroView, Passos-Ferreira discusses recent evidence for and against consciousness in newborn babies. She argues that the weight of evidence from neuroimaging and behavioral studies supports the thesis that newborn infants are conscious.


Subject(s)
Consciousness , Humans , Consciousness/physiology , Infant, Newborn , Brain/physiology , Brain/diagnostic imaging
8.
Neuron ; 112(10): 1611-1625, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38754373

ABSTRACT

Consciousness can be conceptualized as varying along at least two dimensions: the global state of consciousness and the content of conscious experience. Here, we highlight the cellular and systems-level contributions of the thalamus to conscious state and then argue for thalamic contributions to conscious content, including the integrated, segregated, and continuous nature of our experience. We underscore vital, yet distinct roles for core- and matrix-type thalamic neurons. Through reciprocal interactions with deep-layer cortical neurons, matrix neurons support wakefulness and determine perceptual thresholds, whereas the cortical interactions of core neurons maintain content and enable perceptual constancy. We further propose that conscious integration, segregation, and continuity depend on the convergent nature of corticothalamic projections enabling dimensionality reduction, a thalamic reticular nucleus-mediated divisive normalization-like process, and sustained coherent activity in thalamocortical loops, respectively. Overall, we conclude that the thalamus plays a central topological role in brain structures controlling conscious experience.


Subject(s)
Consciousness , Thalamus , Thalamus/physiology , Consciousness/physiology , Humans , Animals , Neural Pathways/physiology , Neurons/physiology , Cerebral Cortex/physiology , Wakefulness/physiology
9.
Neuron ; 112(10): 1626-1641, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38754374

ABSTRACT

The involvement of the prefrontal cortex (PFC) in consciousness is an ongoing focus of intense investigation. An important question is whether representations of conscious contents and experiences in the PFC are confounded by post-perceptual processes related to cognitive functions. Here, I review recent findings suggesting that neuronal representations of consciously perceived contents-in the absence of post-perceptual processes-can indeed be observed in the PFC. Slower ongoing fluctuations in the electrophysiological state of the PFC seem to control the stability and updates of these prefrontal representations of conscious awareness. In addition to conscious perception, the PFC has been shown to play a critical role in controlling the levels of consciousness as observed during anesthesia, while prefrontal lesions can result in severe loss of perceptual awareness. Together, the convergence of these processes in the PFC suggests its integrative role in consciousness and highlights the complex nature of consciousness itself.


Subject(s)
Consciousness , Prefrontal Cortex , Prefrontal Cortex/physiology , Humans , Consciousness/physiology , Animals , Awareness/physiology , Perception/physiology
10.
Sci Rep ; 14(1): 10593, 2024 05 08.
Article in English | MEDLINE | ID: mdl-38719939

ABSTRACT

Previous research on the neural correlates of consciousness (NCC) in visual perception revealed an early event-related potential (ERP), the visual awareness negativity (VAN), to be associated with stimulus awareness. However, due to the use of brief stimulus presentations in previous studies, it remains unclear whether awareness-related negativities represent a transient onset-related response or correspond to the duration of a conscious percept. Studies are required that allow prolonged stimulus presentation under aware and unaware conditions. The present ERP study aimed to tackle this challenge by using a novel stimulation design. Male and female human participants (n = 62) performed a visual task while task-irrelevant line stimuli were presented in the background for either 500 or 1000 ms. The line stimuli sometimes contained a face, which needed so-called visual one-shot learning to be seen. Half of the participants were informed about the presence of the face, resulting in faces being perceived by the informed but not by the uninformed participants. Comparing ERPs between the informed and uninformed group revealed an enhanced negativity over occipitotemporal electrodes that persisted for the entire duration of stimulus presentation. Our results suggest that sustained visual awareness negativities (SVAN) are associated with the duration of stimulus presentation.


Subject(s)
Consciousness , Electroencephalography , Evoked Potentials , Visual Perception , Humans , Male , Female , Consciousness/physiology , Visual Perception/physiology , Adult , Young Adult , Evoked Potentials/physiology , Photic Stimulation , Awareness/physiology , Evoked Potentials, Visual/physiology
11.
Neuroimage ; 294: 120647, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38761552

ABSTRACT

Mental representation is a key concept in cognitive science; nevertheless, its neural foundations remain elusive. We employed non-invasive electrical brain stimulation and functional magnetic resonance imaging to address this. During this process, participants perceived flickering red and green visual stimuli, discerning them either as distinct, non-fused colours or as a mentally generated, fused colour (orange). The application of transcranial alternating current stimulation to the medial prefrontal region (a key node of the default-mode network) suppressed haemodynamic activation in higher-order subthalamic and central executive networks associated with the perception of fused colours. This implies that higher-order thalamocortical and default-mode networks are crucial in humans' conscious perception of mental representation.


Subject(s)
Consciousness , Magnetic Resonance Imaging , Transcranial Direct Current Stimulation , Humans , Male , Female , Adult , Transcranial Direct Current Stimulation/methods , Consciousness/physiology , Young Adult , Prefrontal Cortex/physiology , Prefrontal Cortex/diagnostic imaging , Color Perception/physiology , Brain Mapping/methods , Brain/physiology , Brain/diagnostic imaging , Default Mode Network/physiology , Default Mode Network/diagnostic imaging , Photic Stimulation/methods
12.
Med Sci Monit ; 30: e943802, 2024 May 14.
Article in English | MEDLINE | ID: mdl-38741355

ABSTRACT

BACKGROUND The thalamocortical tract (TCT) links nerve fibers between the thalamus and cerebral cortex, relaying motor/sensory information. The default mode network (DMN) comprises bilateral, symmetrical, isolated cortical regions of the lateral and medial parietal and temporal brain cortex. The Coma Recovery Scale-Revised (CRS-R) is a standardized neurobehavioral assessment of disorders of consciousness (DOC). In the present study, 31 patients with hypoxic-ischemic brain injury (HI-BI) were compared for changes in the TCT and DMN with consciousness levels assessed using the CRS-R. MATERIAL AND METHODS In this retrospective study, 31 consecutive patients with HI-BI (17 DOC,14 non-DOC) and 17 age- and sex-matched normal control subjects were recruited. Magnetic resonance imaging was used to diagnose HI-BI, and the CRS-R was used to evaluate consciousness levels at the time of diffusion tensor imaging (DTI). The fractional anisotropy (FA) values and tract volumes (TV) of the TCT and DMN were compared. RESULTS In patients with DOC, the FA values and TV of both the TCT and DMN were significantly lower compared to those of patients without DOC and the control subjects (p<0.05). When comparing the non-DOC and control groups, the TV of the TCT and DMN were significantly lower in the non-DOC group (p<0.05). Moreover, the CRS-R score had strong positive correlations with the TV of the TCT (r=0.501, p<0.05), FA of the DMN (r=0.532, p<0.05), and TV of the DMN (r=0.501, p<0.05) in the DOC group. CONCLUSIONS This study suggests that both the TCT and DMN exhibit strong correlations with consciousness levels in DOC patients with HI-BI.


Subject(s)
Cerebral Cortex , Coma , Consciousness , Diffusion Tensor Imaging , Hypoxia-Ischemia, Brain , Thalamus , Humans , Female , Male , Middle Aged , Thalamus/physiopathology , Thalamus/diagnostic imaging , Hypoxia-Ischemia, Brain/physiopathology , Hypoxia-Ischemia, Brain/diagnostic imaging , Adult , Consciousness/physiology , Diffusion Tensor Imaging/methods , Cerebral Cortex/physiopathology , Cerebral Cortex/diagnostic imaging , Retrospective Studies , Coma/physiopathology , Coma/diagnostic imaging , Magnetic Resonance Imaging/methods , Default Mode Network/physiopathology , Default Mode Network/diagnostic imaging , Consciousness Disorders/physiopathology , Consciousness Disorders/diagnostic imaging , Aged
13.
Cogn Sci ; 48(5): e13453, 2024 05.
Article in English | MEDLINE | ID: mdl-38742274

ABSTRACT

"Autonomous Sensory Meridian Response" (ASMR) refers to a sensory-emotional experience that was first explicitly identified and named within the past two decades in online discussion boards. Since then, there has been mounting psychological and neural evidence of a clustering of properties common to the phenomenon of ASMR, including convergence on the set of stimuli that trigger the experience, the properties of the experience itself, and its downstream effects. Moreover, psychological instruments have begun to be developed and employed in an attempt to measure it. Based on this empirical work, we make the case that despite its nonscientific origins, ASMR is a good candidate for being a real kind in the cognitive sciences. The phenomenon appears to have a robust causal profile and may also have an adaptive evolutionary history. We also argue that a more thorough understanding of the distinctive type of phenomenal experience involved in an ASMR episode can shed light on the functions of consciousness, and ultimately undermine certain "cognitive" theories of consciousness. We conclude that ASMR should be the subject of more extensive scientific investigation, particularly since it may also have the potential for therapeutic applications.


Subject(s)
Consciousness , Humans , Consciousness/physiology , Emotions/physiology , Sensation/physiology
14.
BMJ Open ; 14(5): e083888, 2024 May 31.
Article in English | MEDLINE | ID: mdl-38821572

ABSTRACT

INTRODUCTION: Prolonged disorders of consciousness (pDoC) are a catastrophic condition following brain injury with few therapeutic options. Transcutaneous auricular vagal nerve stimulation (taVNS), a safe, non-invasive intervention modulating thalamo-cortical connectivity and brain function, is a possible treatment option of pDoC. We developed a protocol for a randomised controlled study to evaluate the effectiveness of taVNS on consciousness recovery in patients with pDoC (TAVREC). METHODS AND ANALYSIS: The TAVREC programme is a multicentre, triple-blind, randomised controlled trial with 4 weeks intervention followed by 4 weeks follow-up period. A minimum number of 116 eligible pDoC patients will be recruited and randomly receive either: (1) conventional therapy plus taVNS (30 s monophasic square current of pulse width 300 µs, frequency of 25 Hz and intensity of 1 mA followed by 30 s rest, 60 min, two times per day, for 4 weeks); or (2) conventional therapy plus taVNS placebo. Primary outcome of TAVREC is the rate of improved consciousness level based on the Coma Recovery Scale-Revised (CRS-R) at week 4. Secondary outcomes are CRS-R total and subscale scores, Glasgow Coma Scale score, Full Outline of UnResponsiveness score, ECG parameters, brainstem auditory evoked potential, upper somatosensory evoked potential, neuroimaging parameters from positron emission tomography/functional MRI, serum biomarkers associated with consciousness level and adverse events. ETHICS AND DISSEMINATION: This study was reviewed and approved by the Research Ethics Committee of the First Affiliated Hospital of Nanjing Medical University (Reference number: 2023-SR-392). Findings will be disseminated in a peer-reviewed journal and presented at relevant conferences. TRIAL REGISTRATION NUMBER: ChiCTR2300073950.


Subject(s)
Consciousness Disorders , Transcutaneous Electric Nerve Stimulation , Vagus Nerve Stimulation , Humans , Vagus Nerve Stimulation/methods , Consciousness Disorders/therapy , Consciousness Disorders/physiopathology , China , Transcutaneous Electric Nerve Stimulation/methods , Consciousness , Randomized Controlled Trials as Topic , Adult , Multicenter Studies as Topic , Recovery of Function , Female , Treatment Outcome , Male
15.
Nat Commun ; 15(1): 3906, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38724511

ABSTRACT

Sleepwalking and related parasomnias result from incomplete awakenings out of non-rapid eye movement sleep. Behavioral episodes can occur without consciousness or recollection, or in relation to dream-like experiences. To understand what accounts for these differences in consciousness and recall, here we recorded parasomnia episodes with high-density electroencephalography (EEG) and interviewed participants immediately afterward about their experiences. Compared to reports of no experience (19%), reports of conscious experience (56%) were preceded by high-amplitude EEG slow waves in anterior cortical regions and activation of posterior cortical regions, similar to previously described EEG correlates of dreaming. Recall of the content of the experience (56%), compared to no recall (25%), was associated with higher EEG activation in the right medial temporal region before movement onset. Our work suggests that the EEG correlates of parasomnia experiences are similar to those reported for dreams and may thus reflect core physiological processes involved in sleep consciousness.


Subject(s)
Dreams , Electroencephalography , Parasomnias , Humans , Dreams/physiology , Dreams/psychology , Male , Female , Adult , Parasomnias/physiopathology , Young Adult , Consciousness/physiology , Mental Recall/physiology , Sleep, REM/physiology , Middle Aged , Sleep/physiology
16.
Dialogues Clin Neurosci ; 26(1): 1-23, 2024.
Article in English | MEDLINE | ID: mdl-38767966

ABSTRACT

We introduce here a general model of Functional Neurological Disorders based on the following hypothesis: a Functional Neurological Disorder could correspond to a consciously initiated voluntary top-down process causing involuntary lasting consequences that are consciously experienced and subjectively interpreted by the patient as involuntary. We develop this central hypothesis according to Global Neuronal Workspace theory of consciousness, that is particularly suited to describe interactions between conscious and non-conscious cognitive processes. We then present a list of predictions defining a research program aimed at empirically testing their validity. Finally, this general model leads us to reinterpret the long-debated links between hypnotic suggestion and functional neurological disorders. Driven by both scientific and therapeutic goals, this theoretical paper aims at bringing closer the psychiatric and neurological worlds of functional neurological disorders with the latest developments of cognitive neuroscience of consciousness.


Subject(s)
Consciousness , Nervous System Diseases , Humans , Nervous System Diseases/psychology , Nervous System Diseases/physiopathology , Consciousness/physiology , Models, Neurological , Neurons/physiology , Brain/physiopathology , Brain/physiology
18.
Sci Rep ; 14(1): 11296, 2024 05 17.
Article in English | MEDLINE | ID: mdl-38760391

ABSTRACT

The body and the self change markedly during adolescence, but how does bodily self-consciousness, the pre-reflexive experience of being a bodily subject, change? We addressed this issue by studying embodiment towards virtual avatars in 70 girls aged 10-17 years. We manipulated the synchrony between participants' and avatars' touch or movement, as well as the avatar visual shape or size relative to each participant's body. A weaker avatar's embodiment in case of mismatch between the body seen in virtual reality and the real body is indicative of a more robust bodily self-consciousness. In both the visuo-tactile and the visuo-motor experiments, asynchrony decreased ownership feeling to the same extent for all participants, while the effect of asynchrony on agency feeling increased with age. In the visuo-tactile experiment, incongruence in visual appearance did not affect agency feeling but impacted ownership, especially in older teenage girls. These findings highlight the higher malleability of bodily self-consciousness at the beginning of adolescence and suggest some independence between body ownership and agency.


Subject(s)
Body Image , Self Concept , Humans , Adolescent , Female , Child , Body Image/psychology , Consciousness/physiology , Virtual Reality , Touch Perception/physiology , Touch/physiology , Visual Perception/physiology
19.
Neuron ; 112(10): 1568-1594, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38697113

ABSTRACT

Sleep is a universal, essential biological process. It is also an invaluable window on consciousness. It tells us that consciousness can be lost but also that it can be regained, in all its richness, when we are disconnected from the environment and unable to reflect. By considering the neurophysiological differences between dreaming and dreamless sleep, we can learn about the substrate of consciousness and understand why it vanishes. We also learn that the ongoing state of the substrate of consciousness determines the way each experience feels regardless of how it is triggered-endogenously or exogenously. Dreaming consciousness is also a window on sleep and its functions. Dreams tell us that the sleeping brain is remarkably lively, recombining intrinsic activation patterns from a vast repertoire, freed from the requirements of ongoing behavior and cognitive control.


Subject(s)
Brain , Consciousness , Dreams , Sleep , Humans , Consciousness/physiology , Sleep/physiology , Dreams/physiology , Brain/physiology , Animals
20.
PLoS Comput Biol ; 20(5): e1011350, 2024 May.
Article in English | MEDLINE | ID: mdl-38701063

ABSTRACT

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


Subject(s)
Brain , Computer Simulation , Consciousness Disorders , Magnetic Resonance Imaging , Models, Neurological , Humans , Magnetic Resonance Imaging/methods , Brain/physiopathology , Brain/diagnostic imaging , Consciousness Disorders/physiopathology , Consciousness Disorders/diagnostic imaging , Male , Female , Computational Biology , Adult , Middle Aged , Consciousness/physiology , Brain Mapping/methods , Aged
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