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Reentry (neural Circuitry)
Reentry is a neural structuring of the brain, which is characterized by the ongoing bidirectional exchange of signals along reciprocal axonal fibers linking two or more brain areas. It is hypothesized to allow for widely distributed groups of neurons to achieve integrated and synchronized firing, which is proposed to be a requirement for consciousness, as outlined by Gerald Edelman and Giulio Tononi in their book ''A Universe of Consciousness''.. See also *Embodied philosophy *Neural Darwinism *Primary consciousness *Secondary consciousness Secondary consciousness is an individual's accessibility to their history and plans. The ability allows its possessors to go beyond the limits of the remembered present of primary consciousness.Edelman, G. M. (2003). Naturalizing consciousness: a ... References Neural circuits Neurophysiology {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Neural Network
A neural circuit is a population of neurons interconnected by synapses to carry out a specific function when activated. Neural circuits interconnect to one another to form large scale brain networks. Biological neural networks have inspired the design of artificial neural networks, but artificial neural networks are usually not strict copies of their biological counterparts. Early study Early treatments of neural networks can be found in Herbert Spencer's ''Principles of Psychology'', 3rd edition (1872), Theodor Meynert's ''Psychiatry'' (1884), William James' ''Principles of Psychology'' (1890), and Sigmund Freud's Project for a Scientific Psychology (composed 1895). The first rule of neuronal learning was described by Hebb in 1949, in the Hebbian theory. Thus, Hebbian pairing of pre-synaptic and post-synaptic activity can substantially alter the dynamic characteristics of the synaptic connection and therefore either facilitate or inhibit signal transmission. In 1959, the neur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brain
A brain is an organ that serves as the center of the nervous system in all vertebrate and most invertebrate animals. It is located in the head, usually close to the sensory organs for senses such as vision. It is the most complex organ in a vertebrate's body. In a human, the cerebral cortex contains approximately 14–16 billion neurons, and the estimated number of neurons in the cerebellum is 55–70 billion. Each neuron is connected by synapses to several thousand other neurons. These neurons typically communicate with one another by means of long fibers called axons, which carry trains of signal pulses called action potentials to distant parts of the brain or body targeting specific recipient cells. Physiologically, brains exert centralized control over a body's other organs. They act on the rest of the body both by generating patterns of muscle activity and by driving the secretion of chemicals called hormones. This centralized control allows rapid and coordinated respon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuron
A neuron, neurone, or nerve cell is an electrically excitable cell that communicates with other cells via specialized connections called synapses. The neuron is the main component of nervous tissue in all animals except sponges and placozoa. Non-animals like plants and fungi do not have nerve cells. Neurons are typically classified into three types based on their function. Sensory neurons respond to stimuli such as touch, sound, or light that affect the cells of the sensory organs, and they send signals to the spinal cord or brain. Motor neurons receive signals from the brain and spinal cord to control everything from muscle contractions to glandular output. Interneurons connect neurons to other neurons within the same region of the brain or spinal cord. When multiple neurons are connected together, they form what is called a neural circuit. A typical neuron consists of a cell body (soma), dendrites, and a single axon. The soma is a compact structure, and the axon and dend ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Multisensory Integration
Multisensory integration, also known as multimodal integration, is the study of how information from the different sensory modalities (such as sight, sound, touch, smell, self-motion, and taste) may be integrated by the nervous system. A coherent representation of objects combining modalities enables animals to have meaningful perceptual experiences. Indeed, multisensory integration is central to adaptive behavior because it allows animals to perceive a world of coherent perceptual entities. Multisensory integration also deals with how different sensory modalities interact with one another and alter each other's processing. General introduction Multimodal perception is how animals form coherent, valid, and robust perception by processing sensory stimuli from various modalities. Surrounded by multiple objects and receiving multiple sensory stimulations, the brain is faced with the decision of how to categorize the stimuli resulting from different objects or events in the physical wo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Action Potential
An action potential occurs when the membrane potential of a specific cell location rapidly rises and falls. This depolarization then causes adjacent locations to similarly depolarize. Action potentials occur in several types of animal cells, called excitable cells, which include neurons, muscle cells, and in some plant cells. Certain endocrine cells such as pancreatic beta cells, and certain cells of the anterior pituitary gland are also excitable cells. In neurons, action potentials play a central role in cell-cell communication by providing for—or with regard to saltatory conduction, assisting—the propagation of signals along the neuron's axon toward synaptic boutons situated at the ends of an axon; these signals can then connect with other neurons at synapses, or to motor cells or glands. In other types of cells, their main function is to activate intracellular processes. In muscle cells, for example, an action potential is the first step in the chain of events l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Consciousness
Consciousness, at its simplest, is sentience and awareness of internal and external existence. However, the lack of definitions has led to millennia of analyses, explanations and debates by philosophers, theologians, linguisticians, and scientists. Opinions differ about what exactly needs to be studied or even considered consciousness. In some explanations, it is synonymous with the mind, and at other times, an aspect of mind. In the past, it was one's "inner life", the world of introspection, of private thought, imagination and volition. Today, it often includes any kind of cognition, experience, feeling or perception. It may be awareness, awareness of awareness, or self-awareness either continuously changing or not. The disparate range of research, notions and speculations raises a curiosity about whether the right questions are being asked. Examples of the range of descriptions, definitions or explanations are: simple wakefulness, one's sense of selfhood or sou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gerald Edelman
Gerald Maurice Edelman (; July 1, 1929 – May 17, 2014) was an American biologist who shared the 1972 Nobel Prize in Physiology or Medicine for work with Rodney Robert Porter on the immune system. Edelman's Nobel Prize-winning research concerned discovery of the structure of antibody molecules.Structural differences among antibodies of different specificities by G. M. Edelman, B. Benacerraf, Z. Ovary and M. D. Poulik in ''Proc Natl Acad Sci U S A'' (1961) volume 47, pages 1751-1758. In interviews, he has said that the way the components of the immune system evolve over the life of the individual is analogous to the way the components of the brain evolve in a lifetime. There is a continuity in this way between his work on the immune system, for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Giulio Tononi
Giulio Tononi () is a neuroscientist and psychiatrist who holds the David P. White Chair in Sleep Medicine, as well as a Distinguished Chair in Consciousness Science, at the University of Wisconsin. He is best known for his Integrated Information Theory (IIT), a mathematical theory of consciousness, which he has proposed since 2004. Biography Tononi was born in Trento, Italy, and obtained an M.D. in psychiatry and a Ph.D. in neurobiology at the Sant'Anna School of Advanced Studies in Pisa, Italy. He is an authority on sleep, and in particular the genetics and etiology of sleep. Tononi and collaborators have pioneered several complementary approaches to study sleep: * genomics * proteomics * fruit fly models * rodent models employing multiunit / local field potential recordings in behaving animals * in vivo voltammetry and microscopy * high-density EEG recordings and transcranial magnetic stimulation (TMS) in humans * large-scale computer models of sleep and wakefulness This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
A Universe Of Consciousness
''A Universe of Consciousness: How Matter Becomes Imagination'' is the title of a 2000 book by biologists Gerald Maurice Edelman and Giulio Tononi; published in UK as ''Consciousness: How Matter Becomes Imagination''. This book, written with Giulio Tononi, is the culmination of a series of works by Gerald Edelman on the workings of the brain which include Neural Darwinism and ''Bright Air, Brilliant Fire''. Precis It is divided into six sections: the first three cover existing work from philosophical, neurological and Darwinian perspectives. Part IV presents the novel thesis of the work: the Dynamic Core Hypothesis. The remaining two parts explore how it resolves various philosophical and practical issues. The Background Since Descartes, philosophers have been occupied with the concept of consciousness and its subjective nature has posed a special problem for science. Its nature arises from the neuronal structures in the brain and some understanding of these, together with the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embodied Philosophy
Embodied cognition is the theory that many features of cognition, whether human or otherwise, are shaped by aspects of an organism's entire body. Sensory and motor systems are seen as fundamentally integrated with cognitive processing. The cognitive features include high-level mental constructs (such as concepts and categories) and performance on various cognitive tasks (such as reasoning or judgment). The bodily aspects involve the motor system, the perceptual system, the bodily interactions with the environment (situatedness), and the assumptions about the world built into the organism's functional structure. The embodied mind thesis challenges other theories, such as cognitivism, computationalism, and Cartesian dualism. It is closely related to the extended mind thesis, situated cognition, and enactivism. The modern version depends on insights drawn from up to date research in psychology, linguistics, cognitive science, dynamical systems, artificial intelligence, robotics, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neural Darwinism
Neural Darwinism is a biological, and more specifically Darwinian and selectionist, approach to understanding global brain function, originally proposed by American biologist, researcher and Nobel-Prize recipient Gerald Maurice Edelman (July 1, 1929 – May 17, 2014). Edelman's 1987 book ''Neural Darwinism'' introduced the public to the ''theory of neuronal group selection'' (TNGS) – which is the core theory underlying Edelman's explanation of global brain function. Owing to the book title, TNGS is most commonly referred to as the ''theory of neural Darwinism'', although TNGS has roots going back to Edelman and Mountcastle's 1978 book, ''The Mindful Brain – Cortical Organization and the Group-selective Theory of Higher Brain Function'' – where Edelman's colleague, the American neurophysiologist and anatomist Vernon B. Mountcastle (July 15, 1918 – January 11, 2015), describes the columnar structure of the cortical groups within the neocortex, while Edelman develops his ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Primary Consciousness
Primary consciousness is a term the American biologist Gerald Edelman coined to describe the ability, found in humans and some animals, to integrate observed events with memory to create an awareness of the present and immediate past of the world around them. This form of consciousness is also sometimes called "sensory consciousness". Put another way, primary consciousness is the presence of various subjective sensory contents of consciousness such as sensations, perceptions, and mental images. For example, primary consciousness includes a person's experience of the blueness of the ocean, a bird's song, and the feeling of pain. Thus, primary consciousness refers to being mentally aware of things in the world in the present without any sense of past and future; it is composed of mental images bound to a time around the measurable present.Edelman, G. (2004). ''Wider than the sky: The phenomenal gift of consciousness'': Yale Univ Pr. Conversely, higher order consciousness can be desc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
