Statistical Learning Facilitates Access to Awareness.

Statistical learning is a powerful mechanism that enables the rapid extraction of regularities from sensory inputs. Although numerous studies have established that statistical learning serves a wide range of cognitive functions, it remains unknown whether statistical learning impacts conscious access. To address this question, we applied multiple paradigms in a series of experiments (N = 153 adults): Two reaction-time-based breaking continuous flash suppression (b-CFS) experiments showed that probable objects break through suppression faster than improbable objects. A preregistered accuracy-based b-CFS experiment showed higher localization accuracy for suppressed probable (versus improbable) objects under identical presentation durations, thereby excluding the possibility of processing differences emerging after conscious access (e.g., criterion shifts). Consistent with these findings, a supplemental visual-masking experiment reaffirmed higher localization sensitivity to probable objects over improbable objects. Together, these findings demonstrate that statistical learning alters the competition for scarce conscious resources, thereby potentially contributing to established effects of statistical learning on higher-level cognitive processes that require consciousness.

The evolutionary and neurobiological attributes of consciousness: an update. / Ewolucyjne i neurobiologiczne atrybuty swiadomosci: aktualizacja.

Consciousness is most frequently defined as a subjective experience of mental processes. The phenomenon of consciousness has always been a subject of great interest in various fields of science, including psychiatry, and the most prominent scientists have engaged in research on it. The studies performed in recent years have brought about novel data on the evolutionary and neurobiological attributes of this phenomenon. In the first part of the article, the evolutionary concepts of consciousness are presented, going back to the beginnings of life on our planet. They are proposed by such illustrious scientists as Joseph LeDoux, Daniel Dennett, António Damásio, and Arthur Reber. Each of them presents the issue of consciousness in the context of evolution slightly differently. However, there are many similarities concerning the development of the nervous system and mental life. The second part discusses the novel research on the cognitive and neurobiological components of consciousness. Among many researchers of this issue, we chose the achievements of two British authors such as Chris Frith and Anil Seth. The neuroanatomical and perceptive aspects of both the level and context of consciousness are provided. Besides presenting the contemporary evolutionary and neurobiological concepts of consciousness, the article aims to bring closer the profiles of the prominent researchers of neuroscience mentioned here. This term can be translated into Polish as "neuronauka", although our country's most frequently used name is "neurobiologia."

Propofol disrupts the functional core-matrix architecture of the thalamus in humans.

Research into the role of thalamocortical circuits in anesthesia-induced unconsciousness is difficult due to anatomical and functional complexity. Prior neuroimaging studies have examined either the thalamus as a whole or focused on specific subregions, overlooking the distinct neuronal subtypes like core and matrix cells. We conducted a study of heathy volunteers and functional magnetic resonance imaging during conscious baseline, deep sedation, and recovery. We advanced the functional gradient mapping technique to delineate the functional geometry of thalamocortical circuits, within a framework of the unimodal-transmodal functional axis of the cortex. Here we show a significant shift in this geometry during deep sedation, marked by a transmodal-deficient geometry. This alteration is closely linked to the spatial variations in the matrix cell composition within the thalamus. This research bridges cellular and systems-level understanding, highlighting the crucial role of thalamic core-matrix functional architecture in understanding the neural mechanisms of states of consciousness.

Interoceptive signals shape the earliest markers and neural pathway to awareness at the visual threshold.

Variations in interoceptive signals from the baroreceptors (BRs) across the cardiac and respiratory cycle can modulate cortical excitability and so affect awareness. It remains debated at what stages of processing they affect awareness-related event-related potentials (ERPs) in different sensory modalities. We investigated the influence of the cardiac (systole/diastole) and the respiratory (inhalation/exhalation) phase on awareness-related ERPs. Subjects discriminated visual threshold stimuli while their electroencephalogram, electrocardiogram, and respiration were simultaneously recorded. We compared ERPs and their intracranial generators for stimuli classified correctly with and without awareness as a function of the cardiac and respiratory phase. Cyclic variations of interoceptive signals from the BRs modulated both the earliest electrophysiological markers and the trajectory of brain activity when subjects became aware of the stimuli: an early sensory component (P1) was the earliest marker of awareness for low (diastole/inhalation) and a perceptual component (visual awareness negativity) for high (systole/exhalation) BR activity, indicating that BR signals interfere with the sensory processing of the visual input. Likewise, activity spread from the primary visceral cortex (posterior insula) to posterior parietal cortices during high and from associative interoceptive centers (anterior insula) to the prefrontal cortex during low BR activity. Consciousness is thereby resolved in cognitive/associative regions when BR is low and in perceptual centers when it is high. Our results suggest that cyclic fluctuations of BR signaling affect both the earliest markers of awareness and the brain processes underlying conscious awareness.

Index of Consciousness monitoring may effectively predict and prevent circulatory stress induced by endotracheal intubation under general anesthesia: a prospective randomized controlled trial.

BACKGROUND: The primary objective of anesthesiologists during the induction of anaesthesia is to mitigate the operative stress response resulting from endotracheal intubation. In this prospective, randomized controlled trial, our aim was to assess the feasibility and efficacy of employing Index of Consciousness (IoC, IoC1 and IoC2) monitoring in predicting and mitigating circulatory stress induced by endotracheal intubation for laparoscopic cholecystectomy patients under general anesthesia (GA). METHODS: We enrolled one hundred and twenty patients scheduled for laparoscopic cholecystectomy under GA and randomly allocated them to two groups: IoC monitoring guidance (Group T, n = 60) and bispectral index (BIS) monitoring guidance (Group C, n = 60). The primary endpoints included the heart rate (HR) and mean arterial pressure (MAP) of the patients, as well as the rate of change (ROC) at specific time points during the endotracheal intubation period. Secondary outcomes encompassed the systemic vascular resistance index (SVRI), cardiac output index (CI), stroke volume index (SVI), ROC at specific time points, the incidence of adverse events (AEs), and the induction dosage of remifentanil and propofol during the endotracheal intubation period in both groups. RESULTS: The mean (SD) HR at 1 min after intubation under IoC monitoring guidance was significantly lower than that under BIS monitoring guidance (76 (16) beats/min vs. 82 (16) beats/min, P = 0.049, respectively). Similarly, the mean (SD) MAP at 1 min after intubation under IoC monitoring guidance was lower than that under BIS monitoring guidance (90 (20) mmHg vs. 98 (19) mmHg, P = 0.031, respectively). At each time point from 1 to 5 min after intubation, the number of cases with HR ROC of less than 10% in Group T was significantly higher than in Group C (P < 0.05). Furthermore, between 1 and 3 min and at 5 min post-intubation, the number of cases with HR ROC between 20 to 30% or 40% in Group T was significantly lower than that in Group C (P < 0.05). At 1 min post-intubation, the number of cases with MAP ROC of less than 10% in Group T was significantly higher than that in Group C (P < 0.05), and the number of cases with MAP ROC between 10 to 20% in Group T was significantly lower than that in Group C (P < 0.01). Patients in Group T exhibited superior hemodynamic stability during the peri-endotracheal intubation period compared to those in Group C. There were no significant differences in the frequencies of AEs between the two groups (P > 0.05). CONCLUSION: This promising monitoring technique has the potential to predict the circulatory stress response, thereby reducing the incidence of adverse reactions during the peri-endotracheal intubation period. This technology holds promise for optimizing anesthesia management. TRAIL REGISTRATION:  Chinese Clinical Trail Registry Identifier: ChiCTR2300070237 (20/04/2022).

Elements of episodic memory: lessons from 40 years of research.

40 years ago, Endel Tulving published his hugely influential Elements of Episodic Memory (Oxford: Clarendon Press, 1983). For the first time, this discussed the details of episodic memory (i.e. the ability to remember personal past events), including a specific conscious experience. Ten years later, Tulving defined the ability to mentally project oneself in time to be the critical feature distinguishing episodic from semantic memory ('What is episodic memory?' Curr. Dir. Psychol. Sci. 2, 67-70, doi:10.1111/1467-8721.ep10770899). In this conception, the conscious experience of episodic memory captures the experience of reliving a personal event as it was experienced in the past, while the same ability allows a potential symmetry between remembering the past, and our ability to project into an imagined future. With the recent passing of Endel Tulving, this theme issue offers an opportunity to question our understanding of mental time travel in full.This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'.

Episodic memory without autonoetic consciousness.

Ever since Tulving's influential 1985 article 'Memory and consciousness', it has become traditional to think of autonoetic consciousness as necessary for episodic memory. This paper questions this claim. Specifically, it argues that the construct of autonoetic consciousness lacks validity and that, even if it was valid, it would still not be necessary for episodic memory. The paper ends with a proposal to go back to a functional/computational characterization of episodic memory in which its characteristic phenomenology is a contingent feature of the retrieval process and, as a result, open to empirical scrutiny. The proposal also dovetails with recent taxonomies of memory that are independent of conscious awareness and suggests strategies to evaluate within- and between-individual variability in the conscious experience of episodic memories in human and non-human agents. This article is part of the theme issue 'Elements of episodic memory: lessons from 40 years of research'.

Superconscious processes as mental images of a higher order (in the context of telezombification).

OBJECTIVE: Aim: The paper aims to examine superconscious processes as mental images of a higher order in the context of telezombification. PATIENTS AND METHODS: Materials and Methods: The authors used interpretive research paradigm, psychoanalysis, basic principles of hermeneutics, phenomenological approach along with general scientific methods, such as induction, deduction, generalization, etc. CONCLUSION: Conclusions: With the beginning of the russian full-scale attack on Ukraine, russian atrocities in Bucha, Mariupol and other cities and villages of the country, many Ukrainian citizens asked about what has happened to the russian society, the state authorities, who set the goal of destroying Ukraine as a state and all its inhabitants as a nation. Then Ukrainians have labelled the invaders and the authorities of Russia as non-humans. And this is a fair name for them. The fact is that these occupiers and their neo-Nazi leaders have a destroyed, distorted consciousness as a result of which they became incapable of realizing their thought processes. The consciousness of such persons gradually degrades towards animal thinking, the so-called proto-thinking. This is one direction to not realizing one's intentions and actions at the level of both subconscious and partially conscious analysis of primary mental images (images of a first and second orders). The second direction is the role of superconscious processes, in particular mental images of a higher level, which also form the worldview positions of an individual in the process of viewing and listening to certain information, while remaining, at the same time, unconscious until a certain time. Together, these directions form a person's attitude to existing social and worldview problems.

[Current progress on characteristics of intracranial electrophysiology related to prolonged disorders of consciousness].

Prolonged disorders of consciousness (pDOC) are pathological conditions of alterations in consciousness caused by various severe brain injuries, profoundly affecting patients' life ability and leading to a huge burden for both the family and society. Exploring the mechanisms underlying pDOC and accurately assessing the level of consciousness in the patients with pDOC provide the basis of developing therapeutic strategies. Research of non-invasive functional neuroimaging technologies, such as functional magnetic resonance (fMRI) and scalp electroencephalography (EEG), have demonstrated that the generation, maintenance and disorders of consciousness involve functions of multiple cortical and subcortical brain regions, and their networks. Invasive intracranial neuroelectrophysiological technique can directly record the electrical activity of subcortical or cortical neurons with high signal-to-noise ratio and spatial resolution, which has unique advantages and important significance for further revealing the brain function and disease mechanism of pDOC. Here we reviewed the current progress of pDOC research based on two intracranial electrophysiological signals, spikes reflecting single-unit activity and field potential reflecting multi-unit activities, and then discussed the current challenges and gave an outlook on future development, hoping to promote the study of pathophysiological mechanisms related to pDOC and provide guides for the future clinical diagnosis and therapy of pDOC.

Evaluating the explanatory power of the Conscious Turing Machine.

The recent "Conscious Turing Machine" (CTM) proposal offered by Manuel and Lenore Blum aims to define and explore consciousness, contribute to the solution of the hard problem, and demonstrate the value of theoretical computer science with respect to the study of consciousness. Surprisingly, given the ambitiousness and novelty of the proposal (and the prominence of its creators), CTM has received relatively little attention. We here seek to remedy this by offering an exhaustive evaluation of CTM. Our evaluation considers the explanatory power of CTM in three different domains of interdisciplinary consciousness studies: the philosophy of mind, cognitive neuroscience, and computation. Based on our evaluation in each of the target domains, at present, any claim that CTM constitutes progress is premature. Nevertheless, the model has potential, and we highlight several possible avenues of future research which proponents of the model may pursue in its development.

Covert Consciousness in the ICU.

OBJECTIVES: For critically ill patients with acute severe brain injuries, consciousness may reemerge before behavioral responsiveness. The phenomenon of covert consciousness (i.e., cognitive motor dissociation) may be detected by advanced neurotechnologies such as task-based functional MRI (fMRI) and electroencephalography (EEG) in patients who appear unresponsive on the bedside behavioral examination. In this narrative review, we summarize the state-of-the-science in ICU detection of covert consciousness. Further, we consider the prognostic and therapeutic implications of diagnosing covert consciousness in the ICU, as well as its potential to inform discussions about continuation of life-sustaining therapy for patients with severe brain injuries. DATA SOURCES: We reviewed salient medical literature regarding covert consciousness. STUDY SELECTION: We included clinical studies investigating the diagnostic performance characteristics and prognostic utility of advanced neurotechnologies such as task-based fMRI and EEG. We focus on clinical guidelines, professional society scientific statements, and neuroethical analyses pertaining to the implementation of advanced neurotechnologies in the ICU to detect covert consciousness. DATA EXTRACTION AND DATA SYNTHESIS: We extracted study results, guideline recommendations, and society scientific statement recommendations regarding the diagnostic, prognostic, and therapeutic relevance of covert consciousness to the clinical care of ICU patients with severe brain injuries. CONCLUSIONS: Emerging evidence indicates that covert consciousness is present in approximately 15-20% of ICU patients who appear unresponsive on behavioral examination. Covert consciousness may be detected in patients with traumatic and nontraumatic brain injuries, including patients whose behavioral examination suggests a comatose state. The presence of covert consciousness in the ICU may predict the pace and extent of long-term functional recovery. Professional society guidelines now recommend assessment of covert consciousness using task-based fMRI and EEG. However, the clinical criteria for patient selection for such investigations are uncertain and global access to advanced neurotechnologies is limited.

Assessing Consciousness in Patients With Disorders of Consciousness Using a Musical Stimulation Paradigm and Verifiable Criteria.

Numerous studies have shown that musical stimulation can activate corresponding functional brain areas. Electroencephalogram (EEG) activity during musical stimulation can be used to assess the consciousness states of patients with disorders of consciousness (DOC). In this study, a musical stimulation paradigm and verifiable criteria were used for consciousness assessment. Twenty-nine participants (13 healthy subjects, 6 patients in a minimally conscious state (MCS) and 10 patients in a vegetative state (VS)) were recruited, and EEG signals were collected while participants listened to preferred and relaxing music. Fusion features based on differential entropy (DE), common spatial pattern (CSP), and EEG-based network pattern (ENP) features were extracted from EEG signals, and a convolutional neural network-long short-term memory (CNN-LSTM) model was employed to classify preferred and relaxing music.The results showed that the average classification accuracy for healthy subjects reached 85.58%. For two of the patients in the MCS group, the classification accuracies reached 78.18% and 66.14%, and they were diagnosed with emergence from MCS (EMCS) two months later. The accuracies of three patients in the VS group were 58.18%, 64.32% and 62.05%, with two patients showing slight increases in scale scores. Our study suggests that musical stimulation could be an effective method for consciousness detection, with significant diagnostic implications for patients with DOC.

Children with developmental coordination disorder display atypical interhemispheric connectivity during conscious and subconscious rhythmic auditory-motor synchronization.

Children with developmental coordination disorder (DCD) display difficulties in perception-action coupling when engaging in tasks requiring predictive timing. We investigated the influence of awareness on auditory-motor adjustments to small and large rhythmic perturbations in the auditory sequence to examine whether children synchronize their movements automatically or through planning and whether those adjustments occur consciously or subconsciously. Electroencephalography (EEG) was used to assess functional connectivity patterns underlying different adjustment strategies. Thirty-two children aged 7-11 participated, including children with DCD and their typically developing (TD) peers with and without musical training. All children automatically adjusted their motor responses to small rhythmic perturbations by employing the anticipatory mode, even when those changes were consciously undetectable. Planned adjustments occurred only when children consciously detected large fluctuations (Δ 20%), which required a shift from predictive to reactive strategies. Compared to TD peers, children with DCD showed reduced interhemispheric connectivity during planned adjustments and displayed similar neural patterns regardless of task constraints. Notably, they benefited from rhythmic entrainment despite having increased variability and lower perceptual acuity. Musical training was associated with enhanced auditory-perceptual timing, reduced variability, and increased interhemispheric coherence. These insights are important for the therapeutic application of auditory/rhythm-based interventions in children with DCD.

Prognosis of patients with prolonged disorders of consciousness after brain injury: a longitudinal cohort study.

Background: The findings regarding the prognosis of prolonged disorders of consciousness (PDOC) vary widely among different studies. This study aims to investigate the mortality, consciousness recovery and disabilities of patients with PDOC after brain injury. Methods: A total of 204 patients with PDOC were included in a longitudinal cohort study, including 129 males and 75 females. There were 112 cases of traumatic brain injury (TBI), 62 cases of cerebral hemorrhage (CH), 13 cases of cerebral infarction (CI) and 17 cases of ischemic hypoxic encephalopathy (IHE). The status of consciousness at 1, 2, 3, 6, 12, 18, 24, 36, 48 months of the disease course was assessed or followed up using the Revised Coma Recovery Scale (CRS-R). If the patients were conscious, the disability Rating Scale (DRS) was also performed. The prognosis of different PDOC including coma, vegetative state (VS) and minimal conscious state (MCS) was analyzed. The survival patients were screened for variables and included in multivariate binary Logistic regression to screen the factors affecting the recovery of consciousness. Results: The mortality rates at 12, 24, 36, and 48 months were 10.7, 23.4, 38.9, and 68.4%, respectively. The median time of death was 18 months (8.75, 29). The probability of MCS regaining consciousness was higher than VS (p < 0.05), with the degree of disability left lower than VS (p < 0.05). There was no significant difference between MCS- and MCS+ groups in terms of the probability of regaining consciousness, the extent of residual disability, and mortality rates (p > 0.05). The mortality rate of coma was higher than that of other PDOC (p < 0.05). The mortality rate of MCS was lower than that of VS, but the difference was not statistically significant (p > 0.05). The probability of consciousness recovery after TBI was the highest and the mortality rate was the lowest. The possibility of consciousness recovery in IHE was the least, and the mortality rate of CI was the highest. The cause of brain injury and initial CRS-R score were the factors affecting the consciousness recovery of patients (p < 0.05). Conclusion: The prognosis of MCS is more favorable than VS, with comparable outcomes between MCS- and MCS+, while comatose patients was the poorest. TBI has the best prognosis and IHE has the worst prognosis.

Existence of multiple transitions of the critical state due to anesthetics.

Scale-free statistics of coordinated neuronal activity, suggesting a universal operating mechanism across spatio-temporal scales, have been proposed as a necessary condition of healthy resting-state brain activity. Recent studies have focused on anesthetic agents to induce distinct neural states in which consciousness is altered to understand the importance of critical dynamics. However, variation in experimental techniques, species, and anesthetics, have made comparisons across studies difficult. Here we conduct a survey of several common anesthetics (isoflurane, pentobarbital, ketamine) at multiple dosages, using calcium wide-field optical imaging of the mouse cortex. We show that while low-dose anesthesia largely preserves scale-free statistics, surgical plane anesthesia induces multiple dynamical modes, most of which do not maintain critical avalanche dynamics. Our findings indicate multiple pathways away from default critical dynamics associated with quiet wakefulness, not only reflecting differences between these common anesthetics but also showing significant variations in individual responses. This is suggestive of a non-trivial relationship between criticality and the underlying state of the subject.

Upper bounds for integrated information.

Originally developed as a theory of consciousness, integrated information theory provides a mathematical framework to quantify the causal irreducibility of systems and subsets of units in the system. Specifically, mechanism integrated information quantifies how much of the causal powers of a subset of units in a state, also referred to as a mechanism, cannot be accounted for by its parts. If the causal powers of the mechanism can be fully explained by its parts, it is reducible and its integrated information is zero. Here, we study the upper bound of this measure and how it is achieved. We study mechanisms in isolation, groups of mechanisms, and groups of causal relations among mechanisms. We put forward new theoretical results that show mechanisms that share parts with each other cannot all achieve their maximum. We also introduce techniques to design systems that can maximize the integrated information of a subset of their mechanisms or relations. Our results can potentially be used to exploit the symmetries and constraints to reduce the computations significantly and to compare different connectivity profiles in terms of their maximal achievable integrated information.

Time consciousness: Silence, mindfulness, and subjective time perception.

Although recent theories of consciousness have emerged to define what consciousness is, an under-represented aspect within this field remains: time consciousness. However, the subjective passage of time is modulated by changing experiences within different situational contexts and by self-awareness. The experience of silence influences our awareness of self, space, and time, and it impacts on psychological well-being. The present review describes how self and time are influenced by different situations of silence (pure silence indoors and outdoors, the "just thinking" situation, and the combination of silence with deep relaxation). Also, the changes in time experience during a "forced" waiting situation due to the COVID-19 lockdown are presented in order to highlight the role of boredom in waiting situations and in situations in which we are alone with "our thoughts." Finally, in the context of the importance of creating silence through meditation practices, the alterations to one's sense of self and time during mindfulness meditation are reviewed. These studies are discussed within the framework of the cognitive models of prospective time perception, such as the attentional-gate model and the model of self-regulation and self-awareness.

Creativity and consciousness in motion: The roundtrip of "mindful" and "mindless" processes in embodied creativity.

In this opinion paper, we make a journey across different accounts of creativity that emphasize either the mindful, conscious and cognitive expression of creativity, or its mindless, unconscious and sensorimotor expression. We try to go beyond dichotomy, putting creativity in motion and outlining its embodied and enactive features. Based on the assumption that no creative act is purely conscious or purely unconscious, our discussion on creativity relies on the distinction of three types of creativity that complementarily contribute to the creative process through shifts in the activation of their substrates in the brain: the deliberate, spontaneous and flow types of creativity. The latter is a hybrid and embodied type, in which movement and physical activity meet creativity. We then focus on the most fascinating contribution of unconscious processes and mind wandering to spontaneous and flow modes of creativity, exploring what happens when the individual apparently takes a break from a deliberate and effortful search for solutions and the creative process progresses through an incubation phase. This phase and the overall creative process can be facilitated by physical activity which, depending on its features and context, can disengage the cognitive control network and free the mind from filters that constrain cognitive processes or, conversely, can engage attentional control on sensorimotor and cognitive task components in a mindful way. Lastly, we focus on the unique features of the outer natural environment of physical activity and of the inner environment during mindful movements that can restore capacities and boost creativity.

Breathwork-induced psychedelic experiences modulate neural dynamics.

Breathwork is an understudied school of practices involving intentional respiratory modulation to induce an altered state of consciousness (ASC). We simultaneously investigate the phenomenological and neural dynamics of breathwork by combining Temporal Experience Tracing, a quantitative methodology that preserves the temporal dynamics of subjective experience, with low-density portable EEG devices. Fourteen novice participants completed a course of up to 28 breathwork sessions-of 20, 40, or 60 min-in 28 days, yielding a neurophenomenological dataset of 301 breathwork sessions. Using hypothesis-driven and data-driven approaches, we found that "psychedelic-like" subjective experiences were associated with increased neural Lempel-Ziv complexity during breathwork. Exploratory analyses showed that the aperiodic exponent of the power spectral density-but not oscillatory alpha power-yielded similar neurophenomenological associations. Non-linear neural features, like complexity and the aperiodic exponent, neurally map both a multidimensional data-driven composite of positive experiences, and hypothesis-driven aspects of psychedelic-like experience states such as high bliss.