Unconscious Perception of Vernier Offsets.

The comparison between conscious and unconscious perception is a cornerstone of consciousness science. However, most studies reporting above-chance discrimination of unseen stimuli do not control for criterion biases when assessing awareness. We tested whether observers can discriminate subjectively invisible offsets of Vernier stimuli when visibility is probed using a bias-free task. To reduce visibility, stimuli were either backward masked or presented for very brief durations (1-3 milliseconds) using a modern-day Tachistoscope. We found some behavioral indicators of perception without awareness, and yet, no conclusive evidence thereof. To seek more decisive proof, we simulated a series of Bayesian observer models, including some that produce visibility judgements alongside type-1 judgements. Our data are best accounted for by observers with slightly suboptimal conscious access to sensory evidence. Overall, the stimuli and visibility manipulations employed here induced mild instances of blindsight-like behavior, making them attractive candidates for future investigation of this phenomenon.

Confidence in consciousness research.

To study (un)conscious perception and test hypotheses about consciousness, researchers need procedures for determining whether subjects consciously perceive stimuli or not. This article is an introduction to a family of procedures called "confidence-based procedures," which consist in interpreting metacognitive indicators as indicators of consciousness. I assess the validity and accuracy of these procedures, and answer a series of common objections to their use in consciousness research. I conclude that confidence-based procedures are valid for assessing consciousness, and, in most cases, accurate enough for our practical and scientific purposes. This article is categorized under: Psychology > Perception and Psychophysics Philosophy > Consciousness.

Fluid overload and mortality in critically ill patients with severe heart failure and cardiogenic shock-An observational cohort study.

Objective: Patients with heart failure (HF) and cardiogenic shock are especially prone to the negative effects of fluid overload (FO); however, fluid resuscitation in respective patients is sometimes necessary resulting in FO. We aimed to study the association of FO at ICU discharge with 30-day mortality in patients admitted to the ICU due to severe heart failure and/or cardiogenic shock. Methods: Retrospective, single-center cohort study. Patients with admission diagnoses of severe HF and/or cardiogenic shock were eligible. The following exclusion criteria were applied: (I) patients younger than 16 years, (II) patients admitted to our intermediate care unit, and (III) patients with incomplete data to determine FO at ICU discharge. We used a cumulative weight-adjusted definition of fluid balance and defined more than 5% as FO. The data were analyzed by univariate and adjusted univariate logistic regression. Results: We included 2,158 patients in our analysis. 185 patients (8.6%) were fluid overloaded at ICU discharge. The mean FO in the FO group was 7.2% [interquartile range (IQR) 5.8-10%]. In patients with FO at ICU discharge, 30-day mortality was 22.7% compared to 11.7% in non-FO patients (p < 0.001). In adjusted univariate logistic regression, we did not observe any association of FO at discharge with 30-day mortality [odds ratio (OR) 1.48; 95% confidence interval (CI) 0.81-2.71, p = 0.2]. No association between FO and 30-day mortality was found in the subgroups with HF only or cardiogenic shock (all p > 0.05). Baseline lactate (adjusted OR 1.27; 95% CI 1.13-1.42; p < 0.001) and cardiac surgery at admission (adjusted OR 1.94; 95% CI 1.0-3.76; p = 0.05) were the main associated factors with FO at ICU discharge. Conclusion: In patients admitted to the ICU due to severe HF and/or cardiogenic shock, FO at ICU discharge seems not to be associated with 30-day mortality.

Putting the "mental" back in "mental disorders": a perspective from research on fear and anxiety.

Mental health problems often involve clusters of symptoms that include subjective (conscious) experiences as well as behavioral and/or physiological responses. Because the bodily responses are readily measured objectively, these have come to be emphasized when developing treatments and assessing their effectiveness. On the other hand, the subjective experience of the patient reported during a clinical interview is often viewed as a weak correlate of psychopathology. To the extent that subjective symptoms are related to the underlying problem, it is often assumed that they will be taken care of if the more objective behavioral and physiological symptoms are properly treated. Decades of research on anxiety disorders, however, show that behavioral and physiological symptoms do not correlate as strongly with subjective experiences as is typically assumed. Further, the treatments developed using more objective symptoms as a marker of psychopathology have mostly been disappointing in effectiveness. Given that "mental" disorders are named for, and defined by, their subjective mental qualities, it is perhaps not surprising, in retrospect, that treatments that have sidelined mental qualities have not been especially effective. These negative attitudes about subjective experience took root in psychiatry and allied fields decades ago when there were few avenues for scientifically studying subjective experience. Today, however, cognitive neuroscience research on consciousness is thriving, and offers a viable and novel scientific approach that could help achieve a deeper understanding of mental disorders and their treatment.

The blood oxygen level dependent (BOLD) effect of in-vitro myoglobin and hemoglobin.

The presence of deoxygenated hemoglobin (Hb) results in a drop in T2 and T2* in magnetic resonance imaging (MRI), known as the blood oxygenation level-dependent (BOLD-)effect. The purpose of this study was to investigate if deoxygenated myoglobin (Mb) exerts a BOLD-like effect. Equine Met-Mb powder was dissolved and converted to oxygenated Mb. T1, T2, T2*-maps and BOLD-bSSFP images at 3Tesla were used to scan 22 Mb samples and 12 Hb samples at room air, deoxygenation, reoxygenation and after chemical reduction. In Mb, T2 and T2* mapping showed a significant decrease after deoxygenation (- 25% and - 12%, p < 0.01), increase after subsequent reoxygenation (+ 17% and 0% vs. room air, p < 0.01), and finally a decrease in T2 after chemical reduction (- 28%, p < 0.01). An opposite trend was observed with T1 for each stage, while chemical reduction reduced BOLD-bSSFP signal (- 3%, p < 0.01). Similar deflections were seen at oxygenation changes in Hb. The T1 changes suggests that the oxygen content has been changed in the specimen. The shortening of transverse relaxation times in T2 and T2*-mapping after deoxygenation in Mb specimens are highly indicative of a BOLD-like effect.

Higher-order theories do just fine.

Doerig et al. have set several criteria that theories of consciousness need to fulfill. By these criteria, higher-order theories fare better than most existing theories. But they also argue that higher-order theories may not be able to answer both the 'small network argument' and the 'other systems argument'. In response, we focus on the case of the Perceptual Reality Monitoring theory to explain why higher-order theories do just fine.

Defending subjective inflation: an inference to the best explanation.

In a recent opinion piece, Abid (2019) criticizes the hypothesis that subjective inflation may partly account for apparent phenomenological richness across the visual field and outside the focus of attention. In response, we address three main issues. First, we maintain that inflation should be interpreted as an intraperceptual-and not post-perceptual-phenomenon. Second, we describe how inflation may differ from filling-in. Finally, we contend that, in general, there is sufficient evidence to tip the scales toward intraperceptual interpretations of visibility and confidence judgments.

A little history goes a long way toward understanding why we study consciousness the way we do today.

Consciousness is currently a thriving area of research in psychology and neuroscience. While this is often attributed to events that took place in the early 1990s, consciousness studies today are a continuation of research that started in the late 19th century and that continued throughout the 20th century. From the beginning, the effort built on studies of animals to reveal basic principles of brain organization and function, and of human patients to gain clues about consciousness itself. Particularly important and our focus here is research in the 1950s, 1960s, and 1970s involving three groups of patients-amnesia, split brain, and blindsight. Across all three groups, a similar pattern of results was found-the patients could respond appropriately to stimuli that they denied seeing (or in the case of amnesiacs, having seen before). These studies paved the way for the current wave of research on consciousness. The field is, in fact, still grappling with the implications of the findings showing that the ability to consciously know and report the identity of a visual stimulus can be dissociated in the brain from the mechanisms that underlie the ability to behave in a meaningful way to the same stimulus.

An Informal Internet Survey on the Current State of Consciousness Science.

The scientific study of consciousness emerged as an organized field of research only a few decades ago. As empirical results have begun to enhance our understanding of consciousness, it is important to find out whether other factors, such as funding for consciousness research and status of consciousness scientists, provide a suitable environment for the field to grow and develop sustainably. We conducted an online survey on people's views regarding various aspects of the scientific study of consciousness as a field of research. 249 participants completed the survey, among which 80% were in academia, and around 40% were experts in consciousness research. Topics covered include the progress made by the field, funding for consciousness research, job opportunities for consciousness researchers, and the scientific rigor of the work done by researchers in the field. The majority of respondents (78%) indicated that scientific research on consciousness has been making progress. However, most participants perceived obtaining funding and getting a job in the field of consciousness research as more difficult than in other subfields of neuroscience. Overall, work done in consciousness research was perceived to be less rigorous than other neuroscience subfields, but this perceived lack of rigor was not related to the perceived difficulty in finding jobs and obtaining funding. Lastly, we found that, overall, the global workspace theory was perceived to be the most promising (around 28%), while most non-expert researchers (around 22% of non-experts) found the integrated information theory (IIT) most promising. We believe the survey results provide an interesting picture of current opinions from scientists and researchers about the progresses made and the challenges faced by consciousness research as an independent field. They will inspire collective reflection on the future directions regarding funding and job opportunities for the field.

A role for the anterior insular cortex in the global neuronal workspace model of consciousness.

According to the global neuronal workspace model of consciousness, consciousness results from the global broadcast of information throughout the brain. The global neuronal workspace is mainly constituted by a fronto-parietal network. The anterior insular cortex is part of this global neuronal workspace, but the function of this region has not yet been defined within the global neuronal workspace model of consciousness. In this review, I hypothesize that the anterior insular cortex implements a cross-modal priority map, the function of which is to determine priorities for the processing of information and subsequent entrance in the global neuronal workspace.

Extrapyramidal symptoms in schizophrenia: evidence of blunted cerebral hemodynamics during a planning task.

Acute extrapyramidal symptoms (EPS) occur frequently in schizophrenia, mostly caused by antidopaminergic substances. There have been no published reports on the impact of acute EPS on cerebral blood flow (CBF) or related measures. In the following study, we examined schizophrenic patients with and without EPS during a planning task and measurements of CBF velocity. Sixteen patients with chronic schizophrenia and 16 healthy participants performed a planning paradigm during bilateral functional transcranial Doppler sonography of the middle cerebral arteries. Patients with acute EPS showed blunted CBF velocity exclusively during difficult planning tasks, and correlation analyses confirmed that higher EPS scores were associated with reduced adaption of CBF velocity. EPS in schizophrenia are associated with a detrimental effect on CBF velocity. Hypothetically, compromised adaptation of cerebral hemodynamics during difficult, but not during easy planning tasks is one correlate of dysfunctional frontostriatal circuits in schizophrenic patients with EPS.

[Efficacy and safety of ustekinumab in psoriatic arthritis after anti-TNFα failure in routine practice]. / Ustekinumab dans le rhumatisme psoriasique après échec des anti-TNFα en pratique courante.

PURPOSE: Evaluation of effectiveness and safety of ustekinumab in psoriatic arthritis after anti-TNFα failure. METHODS: We conducted a retrospective and monocentric study. The evaluation of articular and cutaneous effectiveness by the patient was made with numeric scale and satisfaction scale and by the physician during a rhumatological-dermatological consultation. The safety was analyzed by collecting the adverse effects. RESULTS: Nine patients with anti-TNF failure were included. Five of them stopped the treatment because of severe adverse effects. The mean duration treatment of ustekinumab was 24 months. Articular and cutaneous effectiveness were respectively 4.4/10 and 6.7/10. Two thirds of the patients were "satisfied" and one third could stop any analgesic treatment. The mean PASI score decreased from 8.4 to 1.7 after 3 months treatment. Only minor adverse effects were collected and there were no recidivism of the adverse effects observed with anti-TNFα. CONCLUSION: Ustekinumab is an effective and safe alternative for patients with anti-TNFα failure in psoriatic arthritis.