scholarly journals Wakefulness fluctuations elicit behavioural and neural reconfiguration of awareness

2017 ◽  
Author(s):  
Valdas Noreika ◽  
Andrés Canales-Johnson ◽  
Amy Johnson ◽  
Aurina Arnatkevičiūtė ◽  
Justin Koh ◽  
...  
Keyword(s):  
Psychophysical Function ◽  
Human Perception ◽  
Perceptual Awareness ◽  
Dynamic Changes ◽  
Rapid Changes ◽  
The World ◽  
Neural Underpinnings ◽  
Neural Mapping ◽  
The Brain ◽  
Neural Signatures

ABSTRACTMapping the reports of awareness and its neural underpinnings is instrumental to understand the limits of human perception. The capacity to become aware of objects in the world may be studied by suppressing faint target stimuli with strong masking stimuli, or – alternatively – by manipulating the level of wakefulness from full alertness to mild drowsiness. By combining these two approaches, we studied how perceptual awareness is modulated by decreasing wakefulness. We found dynamic changes in behavioural and neural signatures of conscious access in humans between awake and drowsy states. Behaviourally, we show a decrease in the steepness of the psychophysical function for conscious access in drowsy trials. Neural mapping showed delayed processing of target-mask interaction as the consciousness transition progressed, suggesting that the brain resolution of conscious access shifts from early sensory/perceptual to decision-making stages of processing. Once the goal to report the awareness of a target is set, the system behaviourally adapts to rapid changes in wakefulness, revealing the flexibility of the neural signatures of conscious access, and its suppression, to maintain performance.Significance statementMaintaining full alertness for long periods of time in attentionally demanding situations is challenging and may lead to a decrease in performance. We show the effect of wakefulness fluctuations on behaviour and brain dynamics that humans use to maintain performance. We reveal the neural strategies we have to cope with drowsiness by shifting the weights to more flexible brain processes and relaxing the precision of the decisions we take.

5 Models of the world: from perception to hallucination

2020 ◽  
Vol 91 (8) ◽  
pp. e2.3-e2
Author(s):  
Paul Fletcher
Keyword(s):  
Model Building ◽  
Processing System ◽  
Human Perception ◽  
Predictive Processing ◽  
External Reality ◽  
Consultant Psychiatrist ◽  
University Of Cambridge ◽  
The World ◽  
The University ◽  
The Brain

Paul Fletcher is Wellcome Investigator and Bernard Wolfe Professor of Health Neuroscience at the University of Cambridge. He is also Director of Studies for Preclinical Medicine at Clare College and Honorary Consultant Psychiatrist with the Cambridgeshire and Peterborough NHS Foundation Trust. He studied Medicine, before carrying out specialist training in Psychiatry and taking a PhD in cognitive neuroscience. He researches human perception, learning and decision-making in health and mental illness.We do not have direct contact with external reality. We must rely on messages from the sense organs, conveying information about the state of the world and our bodies. These messages are not easy to decipher, being noisy and ambiguous, but from them we have to construct models of the world. I will discuss this challenge and how we are very adept at creating a model of reality based on achieving a balance between what our senses are telling us and our expectations of what should be the case. This is often referred to as the predictive processing framework.Relying on this balance comes at a cost, rendering us vulnerable to illusions and biases and, in more extreme cases, to creating a reality that diverges from that experienced by others. This can arise for a variety of reasons but, at the root, I suggest, lies the nature of the brain as a model-building organ. Though this divergence from reality – psychosis – often seems inexplicable and incomprehensible, I suggest that a few core principles can help us to understand it and offers ways of thinking about how phenomena like hallucinations can be understood. Interestingly, the framework suggests ways in which apparently similar phenomena like hallucinations can arise from distinct alterations to the function of a predictive processing system.

scholarly journals Neural correlates of modal displacement and discourse-updating under (un)certainty

2020 ◽  
Author(s):  
Maxime Tulling ◽  
Ryan Law ◽  
Ailís Cournane ◽  
Liina Pylkkänen
Keyword(s):  
Mental Representation ◽  
Actual World ◽  
Signal Strength ◽  
Neural Correlates ◽  
Human Thought ◽  
Discourse Model ◽  
The World ◽  
Measured Activity ◽  
The Brain ◽  
Neural Signatures

ABSTRACTA hallmark of human thought is the ability to think about not just the actual world, but also about alternative ways the world could be. One way to study this contrast is through language. Language has grammatical devices for expressing possibilities and necessities, such as the words might or must. With these devices, called “modal expressions,” we can study the actual vs. possible contrast in a highly controlled way. While factual utterances such as “There is a monster under my bed” update the here-and-now of a discourse model, a modal version of this sentence, “There might be a monster under my bed,” displaces from the here-and-now and merely postulates a possibility. We used magnetoencephalography (MEG) to test whether the processes of discourse updating and modal displacement dissociate in the brain. Factual and modal utterances were embedded in short narratives, and across two experiments, factual expressions increased the measured activity over modal expressions. However, the localization of the increase appeared to depend on perspective: signal localizing in right temporo-parietal areas increased when updating others’ beliefs, while frontal medial areas seem sensitive to updating one’s own beliefs. The presence of modal displacement did not elevate MEG signal strength in any of our analyses. In sum, this study identifies potential neural signatures of the process by which facts get added to our mental representation of the world.

The Science of Marijuana

2018 ◽  
Author(s):  
Leslie Iversen
Keyword(s):  
Scientific Evidence ◽  
The United States ◽  
Cannabis Use ◽  
Advantages And Disadvantages ◽  
Rapid Changes ◽  
The World ◽  
Recreational Use ◽  
The Brain

Marijuana (cannabis) is the most widely used recreational drug after nicotine and alcohol. This book reviews the rapidly growing body of scientific evidence on cannabis—how it works, the role of endogenous cannabinoids in the brain and body, and the opportunities for new medicines based on such knowledge. The regulation of cannabis use varies considerably throughout the world. This book reviews the rapid changes that have occurred in liberalizing the medical use of cannabis, and in some instances the full legalization of cannabis use, with an emphasis on events in the United States and Canada. The advantages and disadvantages of liberalizing the medical and recreational use of cannabis are discussed in a neutral manner, leaving the reader to decide.

The Demonolexis in Yu. Andrukhovych’s Long Short Story “Recreatsii” (“Recreations”)

2019 ◽  
Vol 26 (27) ◽  
pp. 53-60
Author(s):  
Nina Bosak
Keyword(s):  
Key Words ◽  
Short Story ◽  
Human Perception ◽  
Semantic Group ◽  
Lexical Semantic ◽  
The World

The demonolexis in Yu. Andrukhovych’s long short story “Recreatsii” (“Recreations”) has been analyzed in the article. In the course of the research there have been outlined the following lexical-semantic groups of demonomens: toponymic and onomastic names, modified lexemes, names of the rituals, genuine Ukrainian demonomens, obscene words and expressions, demonomens of Biblical origin, names from the world mythology and general demonolexis. The special lexical-semantic group has been formed by non personificated demonomens, which serve to convey the peculiarities of the contemporary Ukrainian writers’ mentality, their habits through speech. Such nomens help to reveal the protagonist’s soul, show the positive and negative sides of his personal ego, demonstrate the duality of the human perception of the world, indicate the causes of phobias, emotions, sensations. Key words: demonolexis, demonomen, lexical-semantic group, non personificated demonomen.

Pelvic schwannoma

GYNECOLOGY ◽  
2020 ◽  
Vol 22 (5) ◽  
pp. 84-86
Author(s):  
Sergei P. Sinchikhin ◽  
Sarkis G. Magakyan ◽  
Oganes G. Magakyan
Keyword(s):  
Auditory Nerve ◽  
World Literature ◽  
Morphological Study ◽  
Clinical Observation ◽  
Nerve Trunk ◽  
Practical Case ◽  
Surgical Volume ◽  
The World ◽  
Brain And Spinal Cord ◽  
The Brain

Relevance.A neoplasm originated from the myelonic sheath of the nerve trunk is called neurinoma or neurilemmoma, neurinoma, schwannoglioma, schwannoma. This tumor can cause compression and dysfunction of adjacent tissues and organs. The most common are the auditory nerve neurinomas (1 case per 100 000 population per year), the brain and spinal cord neurinomas are rare. In the world literature, there is no information on the occurrences of this tumor in the pelvic region. Description.Presented below is a clinical observation of a 30-year-old patient who was scheduled for myomectomy. During laparoscopy, an unusual tumor of the small pelvis was found and radically removed. A morphological study allowed to identify the remote neoplasm as a neuroma. Conclusion.The presented practical case shows that any tumor can hide under a clinical mask of another disease. The qualification of the doctor performing laparoscopic myomectomy should be sufficient to carry out, if necessary, another surgical volume.

Consciousness, law of nature, and nomological determinism

2018 ◽  
Author(s):  
Xiaoyang Yu
Keyword(s):  
Free Will ◽  
Important Thing ◽  
Law Of Nature ◽  
The World ◽  
The Law ◽  
The Brain

Nomological determinism does not mean everything is predictable. It just means everything follows the law of nature. And the most important thing Is that the brain and consciousness follow the law of nature. In other words, there is no free will. Without life, brain and consciousness, the world follows law of nature, that is clear. The life and brain are also part of nature, and they follow the law of nature. This is due to scientific findings. There are not enough scientific findings for consciousness yet. But I think that the consciousness is a nature phenomenon, and it also follows the law of nature.

Exploring the abnormal signal transduction mediated internet addiction and gaming disorders

2020 ◽  
Vol 15 ◽  
Author(s):  
Bhumika Chauhan ◽  
Sisir Nandi
Keyword(s):  
Signal Transduction ◽  
Internet Addiction ◽  
Internet Gaming Disorder ◽  
Online Data ◽  
Abnormal Signal ◽  
Internet Gaming ◽  
The World ◽  
Loss Of Appetite ◽  
Sleeping Disorder ◽  
The Brain

: The world is connected by the internet. It is very useful because we use Google to find out any new topic, to search new places, to quest updated research, and to get knowledge for learnng. The person around the world can communicate with each other through the Google video conference talk. Internet is frequently used in smartphones, laptops, desktop, and tablet. Excessive affinity towards internet-based online data collection, downloading pictures, videos, cyber relationships, and social media may produce addiction disorders followed by different symptoms such as behaviors change, mind disturbance, depression, anxiety, loss of appetite hyperactivity, sleeping disorder, headache, visual fatigueness, trafficking of memory, attention-deficit, loss of efficiency in work and social detachment which may be caused by an imbalance of neurotransmitters. This is very difficult to control because of abnormal signal transduction in the brain. The present study is an attempt to discuss internet addiction disorder (IAD), internet gaming disorder (IGD), and give awareness to society to get rid of this addiction.

Modeling COVID-19 Growing Trends to Reveal the Differences in the Effectiveness of Non-Pharmaceutical Interventions among Countries in the World (Preprint)

2020 ◽  
Author(s):  
You Chen ◽  
Yubo Feng ◽  
Chao Yan ◽  
Xinmeng Zhang ◽  
Cheng Gao
Keyword(s):  
Secondary Analysis ◽  
Reproduction Rate ◽  
Cumulative Number ◽  
Linear Regression Models ◽  
Growth Data ◽  
Dynamic Changes ◽  
The World ◽  
Four Levels ◽  
Almost All ◽  
Pharmaceutical Interventions

BACKGROUND Adopting non-pharmaceutical interventions (NPIs) can affect COVID-19 growing trends, decrease the number of infected cases, and thus reduce mortality and healthcare demand. Almost all countries in the world have adopted non-pharmaceutical interventions (NPIs) to control the spread rate of COVID-19; however, it is unclear what are differences in the effectiveness of NPIs among these countries. OBJECTIVE We hypothesize that COVID-19 case growth data reveals the efficacy of NPIs. In this study, we conduct a secondary analysis of COVID-19 case growth data to compare the differences in the effectiveness of NPIs among 16 representative countries in the world. METHODS This study leverages publicly available data to learn patterns of dynamic changes in the reproduction rate for sixteen countries covering Asia, Europe, North America, South America, Australia, and Africa. Furthermore, we model the relationships between the cumulative number of cases and the dynamic reproduction rate to characterize the effectiveness of the NPIs. We learn four levels of NPIs according to their effects in the control of COVID-19 growth and categorize the 16 countries into the corresponding groups. RESULTS The dynamic changes of the reproduction rate are learned via linear regression models for all of the studied countries, with the average adjusted R-squared at 0.96 and the 95% confidence interval as [0.94 0.98]. China, South Korea, Argentina, and Australia are at the first level of NPIs, which are the most effective. Japan and Egypt are at the second level of NPIs, and Italy, Germany, France, Netherlands, and Spain, are at the third level. The US and UK have the most inefficient NPIs, and they are at the fourth level of NPIs. CONCLUSIONS COVID-19 case growth data provides evidence to demonstrate the effectiveness of the NPIs. Understanding the differences in the efficacy of the NPIs among countries in the world can give guidance for emergent public health events. CLINICALTRIAL NA

scholarly journals Antagonism between brain regions relevant for cognitive control and emotional memory facilitates the generation of humorous ideas

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Florian Bitsch ◽  
Philipp Berger ◽  
Andreas Fink ◽  
Arne Nagels ◽  
Benjamin Straube ◽  
...  
Keyword(s):  
Cognitive Control ◽  
Positive Emotions ◽  
Emotional Memory ◽  
Brain Regions ◽  
Neural Mechanisms ◽  
Functional Magnetic Resonance ◽  
Frontal Brain ◽  
Successful Resolution ◽  
Neural Underpinnings ◽  
The Brain

AbstractThe ability to generate humor gives rise to positive emotions and thus facilitate the successful resolution of adversity. Although there is consensus that inhibitory processes might be related to broaden the way of thinking, the neural underpinnings of these mechanisms are largely unknown. Here, we use functional Magnetic Resonance Imaging, a humorous alternative uses task and a stroop task, to investigate the brain mechanisms underlying the emergence of humorous ideas in 24 subjects. Neuroimaging results indicate that greater cognitive control abilities are associated with increased activation in the amygdala, the hippocampus and the superior and medial frontal gyrus during the generation of humorous ideas. Examining the neural mechanisms more closely shows that the hypoactivation of frontal brain regions is associated with an hyperactivation in the amygdala and vice versa. This antagonistic connectivity is concurrently linked with an increased number of humorous ideas and enhanced amygdala responses during the task. Our data therefore suggests that a neural antagonism previously related to the emergence and regulation of negative affective responses, is linked with the generation of emotionally positive ideas and may represent an important neural pathway supporting mental health.

scholarly journals Extending the extended consciousness debate: perception, imagination, and the common kind assumption

2021 ◽  
Author(s):  
James Deery
Keyword(s):  
Perceptual Experience ◽  
Phenomenal Consciousness ◽  
Psychological Theory ◽  
Predictive Processing ◽  
Mental Event ◽  
The World ◽  
Predictive Approach ◽  
The Common ◽  
The Relationship ◽  
The Brain

AbstractFor some, the states and processes involved in the realisation of phenomenal consciousness are not confined to within the organismic boundaries of the experiencing subject. Instead, the sub-personal basis of perceptual experience can, and does, extend beyond the brain and body to implicate environmental elements through one’s interaction with the world. These claims are met by proponents of predictive processing, who propose that perception and imagination should be understood as a product of the same internal mechanisms. On this view, as visually imagining is not considered to be world-involving, it is assumed that world-involvement must not be essential for perception, and thus internalism about the sub-personal basis is true. However, the argument for internalism from the unity of perception and imagination relies for its strength on a questionable conception of the relationship between the two experiential states. I argue that proponents of the predictive approach are guilty of harbouring an implicit commitment to the common kind assumption which does not follow trivially from their framework. That is, the assumption that perception and imagination are of the same fundamental kind of mental event. I will argue that there are plausible alternative ways of conceiving of this relationship without drawing internalist metaphysical conclusions from their psychological theory. Thus, the internalist owes the debate clarification of this relationship and further argumentation to secure their position.

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