Sunday, 14 July 2019

A Cognitive Theory of Consciousness By Bernard J. Baars

Front Cover

A Cognitive Theory of Consciousness

By Bernard J. Baars

"Conscious experience is one of the most difficult and thorny problems in psychological science. Its study has been neglected for many years, either because it was thought to be too difficult, or because the relevant evidence was thought to be poor. Bernard Baars suggests a way to specify empirical constraints on a theory of consciousness by contrasting well-established conscious phenomena - such as stimulus representations known to be attended, perceptual, and informative - with closely comparable unconscious ones - such as stimulus representations known to be preperceptual, unattended, or habituated. Adducing data to show that consciousness is associated with a kind of global workplace in the nervous system, and that several brain structures are known to behave in accordance with his theory, Baars helps to clarify many difficult problems."



'A clear-eyed, open-minded analysis of the problems of consciousness, and a wide-ranging synthesis of a variety of approaches. For those who want to join the race to model consciousness, this is the starting line.' Daniel C. Dennett

'With this model, the author sweeps through dozens of phenomena that are well known to students of sensation, perception, learning abstraction, language, thinking, and problem solving. In each case he interprets the model in terms of the global model workplace and thus produces an admirable piece of scholarship. The most enduring contribution of the book may be its challenge to cognitive scientists to return to their roots, to describe and explain consciousness. Without a decent theory of consciousness, cognitive science may be adrift. If that is so, then (this work) deserves to be read by many.' Contemporary Psychology

'The book includes 'numerous whimsical experiments ... in order to demonstrate points best appreciated experimentally. Anyone with a playful nature will find these illustrations captivating.' Contemporary Psychiatry

'The powerful core of Baars' model of consciousness is the global workspace, a kind of central bulletin board. It allows scores of specialized mental subsystems (expert but narrow) to contribute to the resolution of novel problems. Baars is careful and thoughtful, and shows constant concern for the testability of his ideas.' Dr. David Galin, Langley Porter Psychiatry Institute, University of California, San Francisco..."


The Cognitive Science of Science: Explanation, Discovery, and Conceptual Change By Paul Thagard

Front Cover

The Cognitive Science of Science: Explanation, Discovery, and Conceptual Change

By Paul Thagard

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Table of Contents
About Bookshelf
Many disciplines, including philosophy, history, and sociology, have attempted to make sense of how science works. In this book, Paul Thagard examines scientific development from the interdisciplinary perspective of cognitive science. Cognitive science combines insights from researchers in many fields: philosophers analyze historical cases, psychologists carry out behavioral experiments, neuroscientists perform brain scans, and computer modelers write programs that simulate thought processes. Thagard develops cognitive perspectives on the nature of explanation, mental models, theory choice, and resistance to scientific change, considering disbelief in climate change as a case study. He presents a series of studies that describe the psychological and neural processes that have led to breakthroughs in science, medicine, and technology. He shows how discoveries of new theories and explanations lead to conceptual change, with examples from biology, psychology, and medicine. Finally, he shows how the cognitive science of science can integrate descriptive and normative concerns; and he considers the neural underpinnings of certain scientific concepts."

Copyright MIT

Wednesday, 10 July 2019

Pigeons In Space

...weightlessness disorients the pigeons from what's up or down...! they are ok for some time as the cabin is pressurized with air...!


Sunday, 7 July 2019

Cognitive Science - "...the inseparability of the brain and 'mind'...! BRAIN-MIND electrical waves...!

Cognitive Science

Cognitive science is the scientific study of the human mind. It is a highly interdisciplinary field, combining ideas and methods from psychology, computer science, linguistics, philosophy, and neuroscience. The broad goal of cognitive science is to characterize the nature of human knowledge – its forms and content – and how that knowledge is used, processed, and acquired. 

Active areas of cognitive research in the Department include language, memory, visual perception and cognition, thinking and reasoning, social cognition, decision making, and cognitive development. 

The study of cognitive science within BCS illustrates the department’s philosophy that understanding the mind and understanding the brain are ultimately inseparable, even with the gaps that currently exist between the core questions of human cognition and the questions that can be productively addressed in molecular, cellular or systems neuroscience. To bridge these gaps, several cognitive labs maintain a primary or secondary focus on cognitive neuroscience research. There are many opportunities for interaction and collaboration between cognitive and neuroscience labs across BCS and its related centers. 

Cognitive Science

First published Mon Sep 23, 1996; substantive revision Mon Sep 24, 2018
Cognitive science is the interdisciplinary study of mind and intelligence, embracing philosophy, psychology, artificial intelligence, neuroscience, linguistics, and anthropology. Its intellectual origins are in the mid-1950s when researchers in several fields began to develop theories of mind based on complex representations and computational procedures. Its organizational origins are in the mid-1970s when the Cognitive Science Society was formed and the journal Cognitive Science began. Since then, more than one hundred universities in North America, Europe, Asia, and Australia have established cognitive science programs, and many others have instituted courses in cognitive science.

"...Although theory without experiment is empty, experiment without theory is blind. To address the crucial questions about the nature of mind, the psychological experiments need to be interpretable within a theoretical framework that postulates mental representations and procedures. One of the best ways of developing theoretical frameworks is by forming and testing computational models intended to be analogous to mental operations. To complement psychological experiments on deductive reasoning, concept formation, mental imagery, and analogical problem solving, researchers have developed computational models that simulate aspects of human performance. Designing, building, and experimenting with computational models is the central method of artificial intelligence (AI), the branch of computer science concerned with intelligent systems. Ideally in cognitive science, computational models and psychological experimentation go hand in hand, but much important work in AI has examined the power of different approaches to knowledge representation in relative isolation from experimental psychology..."

"...Most work in cognitive science assumes that the mind has mental representations analogous to computer data structures, and computational procedures similar to computational algorithms. Cognitive theorists have proposed that the mind contains such mental representations as logical propositions, rules, concepts, images, and analogies, and that it uses mental procedures such as deduction, search, matching, rotating, and retrieval. The dominant mind-computer analogy in cognitive science has taken on a novel twist from the use of another analog, the brain..."

"... Critique of Cognitive Science
The claim that human minds work by representation and computation is an empirical conjecture and might be wrong. Although the computational-representational approach to cognitive science has been successful in explaining many aspects of human problem solving, learning, and language use, some philosophical critics have claimed that this approach is fundamentally mistaken. Critics of cognitive science have offered such challenges as:..."

"... Philosophy of Cognitive Science
Cognitive science raises many interesting methodological questions that are worthy of investigation by philosophers of science. What is the nature of representation? What role do computational models play in the development of cognitive theories? What is the relation among apparently competing accounts of mind involving symbolic processing, neural networks, and dynamical systems? What is the relation among the various fields of cognitive science such as psychology, linguistics, and neuroscience? Are psychological phenomena subject to reductionist explanations via neuroscience? Are levels of explanation best characterized in terms of ontological levels (molecular, neural, psychological, social) or methodological ones (computational, algorithmic, physical)?

The increasing prominence of neural explanations in cognitive, social, developmental, and clinical psychology raises important philosophical questions about explanation and reduction. Anti-reductionism, according to which psychological explanations are completely independent of neurological ones, is becoming increasingly implausible, but it remains controversial to what extent psychology can be reduced to neuroscience and molecular biology. Crucial to answering questions about the nature of reduction are answers to questions about the nature of explanation. Explanations in psychology, neuroscience, and biology in general are plausibly viewed as descriptions of mechanisms, which are combinations of connected parts that interact to produce regular changes. In psychological explanations, the parts are mental representations that interact by computational procedures to produce new representations. In neuroscientific explanations, the parts are neural populations that interact by electrochemical processes to produce new neural activity that leads to actions. If progress in theoretical neuroscience continues, it should become possible to tie psychological to neurological explanations by showing how mental representations such as concepts are constituted by activities in neural populations, and how computational procedures such as spreading activation among concepts are carried out by neural processes.

The electrical activity emanating from the brain creates frequencies called brainwaves.

  "...Brainwave frequencies are measured in Hertz (Hz), meaning cycles per second. The more cycles per second, the greater the Hertz value.
  There are four major categories of brainwaves ranging from the most activity to the least activity. These are: BETAALPHATHETA and DELTA.
  Each image below depicts a one second snapshot of human brainwave activity, as detected by an electroencephalogram (EEG). As you'll notice, greater values indicate more brainwave activity within the one second time-frame..."

Brain in coma and Brain death

"...Brain death, briefly speaking, is referred to the complete, irreversible, and permanent loss of all brain and brainstem functions. Brain death implies the termination of a human’s life; correspondingly, the diagnosis of brain death is very important (Ad hoc committee of the Harvard medical school to examine the definition of brain ). Although there remain some social disagreements or different diagnosis criteria in clinical practice around the world (Wijdicks ), some standard tests are widely used, such as the apnea test and brainstem function examination. Notably, it is commonly agreed that EEG might serve as an auxiliary and useful tool in the confirmatory tests, for both adults and children (Wijdicks ; Taylor ; Schneider ). Typically, isoelectric EEG recording is required at least 30 min and may last 3–24 h (Wijdicks ); the positive response of EEG tests suggests functioning of the brain. Consequently, the patient in deep coma might show some EEG electroactivity, while the brain-dead patient will not. 1   ..."

"...Brain death is strictly defined medically and legally (Ad hoc committee of the Harvard medical school to examine the definition of brain ; Taylor ); it is defined as the cessation and irreversibility of all brain and brainstem functions. Specifically, brainstem controls basic functions essential to survival, such as breathing and heart rate. Nowadays, despite the differences of clinical practice across countries (Wijdicks ), the standard diagnosis procedure depends on three cardinal neurological features: coma, absent brainstem reflexes, and apnea (Ad hoc committee of the Harvard medical school to examine the definition of brain ).
Because a complete brain death implies the irreversibility of brain function cessation and exclusion of the possibility of recovery of any cerebral and brainstem functions, the irreversibility of coma was emphasized in the report of the ad hoc committee of the Harvard Medical School (Ad hoc committee of the Harvard medical school to examine the definition of brain ). However, the Harvard criterion was presented in a narrative rather than an algorithm form. Nowadays, the Harvard criterion of brain death was not fully agreed and still remained controversial (Niedermeyer ). Brainstem is the lower portion of the brain between the cerebrum and the spinal cord, which controls breathing, swallowing, seeing, hearing, and other vital functions. The examination of brainstem functions in clinical practice might be sophisticated and vary in practice (e.g., pupillary response to light, fixed or variation pupils, corneal reflex, gag reflex, cough reflex, irrigating the ears with cold water, presenting painful stimuli, etc.). The examination of the absence of spinal reflexes will also include the test of ocular movement, facial sensation and facial motor response, pharyngeal and tracheal reflexes. In clinical practice, many physicians request additional confirmatory tests before announcing brain death. The two most common confirmatory tests are the EEG and the cerebral blood flow (CBF) study. 2 Compared to the CBF test, the EEG test is much simpler, and therefore is well recommended in practice (Niedermeyer ). In spite of certain shortcomings discussed earlier, EEG still proved to be invaluable in the evaluation of brain death. Mostly, shortcomings involve the technical concern of artifacts or conceptual misunderstandings like with brainstem death; however, real cerebral EEG waves exclude brain death per definition (Niedermeyer ). Moreover, the technical problem of artifacts can be solved by advanced signal processing methods, which we will also address in this paper.    ..."


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