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 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.

An Essay in Critical Biography—Charles Churchill

PMLA ◽  
1920 ◽  
Vol 35 (2) ◽  
pp. 226-246 ◽  
Author(s):  
Joseph M. Beatty
Keyword(s):  
Personal Information ◽  
Early Career ◽  
Original Material ◽  
University Of Cambridge ◽  
Robert Southey ◽  
The World ◽  
New Material ◽  
Edinburgh Review ◽  
The University ◽  
National Biography

A writer in The Annual Register, soon after the death of Charles Churchill, gave to the world the first account of his life; this was followed by The Genuine Memoirs of Mr. Charles Churchill. To Bell's edition of the poet's works is prefixed a life of the author by Doctor Johnson; this does not add anything new. Kippis, in his Biographia Britannica, followed most of the inaccuracies of the first biographer, but added some new material from his personal information. Anderson used these sources in the British Poets (1795). Robert Southey in his Life of Cowper, and William Tooke in an edition of Churchill's Works (1804) made more elaborate studies of the poet's life, but, unfortunately, were satisfied with earlier biographies or neglected to give careful references to original material. John Forster, in The Edinburgh Review (1845) pointed out many of Tooke's inaccuracies. Every biographer of Churchill from Chalmers in his English Poets to Leslie Stephen in The Dictionary of National Biography, followed Tooke, or Tooke modified by Forster. In 1903, R. F. Scott in his Admissions to the College of St. John the Evangelist in the University of Cambridge, made several valuable contributions to our knowledge about the early career of the satirist. Ferdinand Putschi, in Charles Churchill, sein Leben und seine Werke (1909), had not seen Mr. Scott's book, and followed the earlier biographers.

English Criminal Justice Administration, 1650–1850: A Historiographic Essay

2007 ◽  
Vol 25 (3) ◽  
pp. 593-634 ◽  
Author(s):  
Bruce P. Smith
Keyword(s):  
Criminal Justice ◽  
Legal History ◽  
University Of Cambridge ◽  
Inaugural Lecture ◽  
The World ◽  
History Of ◽  
English Law ◽  
The University

In his inaugural lecture as Downing Professor of the Laws of England at the University of Cambridge, delivered in October 1888, Frederic Maitland offered a set of provocative and now familiar reflections on “Why the history of English law is not written.” According to Maitland, although English archives possessed “a series of records which for continuity, catholicity, minute detail[,] and authoritative value” had “no equal…in the world,” the “unmanageable bulk” of these sources had “overburdened” aspiring historians of English law. As a result, “large provinces” of English legal history remained to be “reclaimed from the waste.” With few willing to undertake such reclamation efforts, the historiography of English law remained as bleak and barren as the bogs from which Maitland's Cambridgeshire had itself only reluctantly emerged.

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.

Brain Basics from a Computational Perspective

2017 ◽  
Author(s):  
Martin V. Butz ◽  
Esther F. Kutter
Keyword(s):  
Current Knowledge ◽  
Imaging Techniques ◽  
Processing System ◽  
Predictive Processing ◽  
Brain Anatomy ◽  
Internal Structures ◽  
Computational Perspective ◽  
Central Nervous Systems ◽  
The Brain ◽  
Human Nervous System

This chapter provides a crude overview of current knowledge in neuroscience about the human nervous system and its functionality. The distinction between the peripheral and central nervous systems is introduced. Next, brain anatomy is introduced, as well as nerve cells and the information processing principles that unfold in biological neural networks. Moreover, brain modules are covered, including their interconnected communication. With modularizations and wiring systematicities in mind, functional and structural systematicities are surveyed, including neural homunculi, cortical columnar structures, and the six-layered structure of the cerebral cortex. Finally, different available brain imaging techniques are contrasted. In conclusion, evidence is surveyed that suggests that the brain can be viewed as a highly modularized predictive processing system, which maintains internal activity and produces internal structures for the purpose of maintaining bodily needs in approximate homeostasis.

An ancient ozone catastrophe?

2007 ◽  
Author(s):  
David Beerling
Keyword(s):  
Life Cycle ◽  
Rank Order ◽  
Intensive Study ◽  
University Of Cambridge ◽  
The World ◽  
The University ◽  
Natural Life ◽  
Test Of Knowledge

The University of Cambridge is one of the oldest seats of learning in the world and is, as befits such an august institution, steeped in tradition and history. One of the more curious traditions, which survived until 1909, was that of publicly ranking undergraduates who had taken the Mathematical Tripos, the oldest and most demanding examination of its kind. Candidates concluded 10 (now 9) semesters of intensive study by sitting a gruelling series of eight lengthy papers, each more difficult than the last, undertaken over a period of nine days. In rank order, the first 30–40 were called wranglers; the man gaining the highest marks of the year held the enviable position of Senior Wrangler. By tradition the positions were published in the London Times, with the accompanying list carrying pictures and short biographies of the top finishers; being a wrangler conveyed a certain degree of national honour and university distinction. Competition to become Senior Wrangler was intense. The examinations involved a test of knowledge, power of recall, concentration, and nerves, and a system of private coaching developed in response to the demands among the elite mathematicians to be Senior Wrangler. Coaches were often those who had previously placed well in the wrangler competition, with good ones able to teach essential mathematics and an ability to produce stock answers concisely so that as many problems as possible could be solved in the time available. The wrangler system evolved its own natural life cycle, ensuring its perpetuity, for a good coach could charge a tidy sum for seeing a student twice weekly over a year and usually had several candidates on his books. A certain William Hopkins was a superlative tutor who had, by 1849, coached 17 Senior Wranglers and 44 top three places. Wranglers in the top few places had the opportunity to take up a pleasant college fellowship or work as a coach fashioning a career to produce more wranglers. Women in the days of Victorian and Edwardian Cambridge were not awarded a degree but were, from 1870 onwards, permitted to sit the Tripos examination.

Bioscience enterprise: Postgraduate education at Cambridge and Auckland

1969 ◽  
Vol 15 (3) ◽  
Author(s):  
Linda Allan ◽  
Joerg Kistler ◽  
Chris Lowe ◽  
Wendell Dunn ◽  
Claire McGowan ◽  
...  
Keyword(s):  
United Kingdom ◽  
New Zealand ◽  
Postgraduate Education ◽  
Employment Opportunities ◽  
The United Kingdom ◽  
University Of Cambridge ◽  
The World ◽  
The University

Leading universities around the world are addressing the demand for science-business-skilled professionals with a variety of novel programmes. The University of Cambridge (the United Kingdom) and University of Auckland (New Zealand) have each developed a Master's in Bioscience Enterprise programme providing specialist business and legal skills relevant to employment in the bio-economy. The biotechnology contexts in which these programmes were developed are significantly different and are reflected in the internship choices, thesis topics and postgraduate employment opportunities. In each case, industry feedback has been excellent to date as evidenced by the increasing engagements of companies in these programmes.

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