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Dehaene–Changeux Model
The Dehaene–Changeux model (DCM), also known as the global neuronal workspace, or global cognitive workspace model, is a part of Bernard Baars's Global workspace theory, global workspace model for consciousness. It is a computer model of the neural correlates of consciousness programmed as a neural network. It attempts to reproduce the swarm behaviour of the brain's ''higher cognitive functions'' such as consciousness, decision-making and the central executive functions. It was developed by cognitive neuroscientists Stanislas Dehaene and Jean-Pierre Changeux beginning in 1986. It has been used to provide a predictive framework to the study of inattentional blindness and the solving of the Tower of London test. History The Dehaene–Changeux model was initially established as a spin glass neural network attempting to represent learning and to then provide a stepping stone towards machine learning, artificial learning among other objectives. It would later be used to predict obse ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bernard Baars
Bernard J. Baars (born 1946 in Amsterdam, the Netherlands) is a former Senior Fellow in Theoretical Neurobiology at the Neurosciences Institute in San Diego, US. He is currently an Affiliated Fellow there. He is best known as the originator of the global workspace theory, a concept of human cognitive architecture and consciousness. He previously served as a professor of psychology at the State University of New York, Stony Brook, where he conducted research into the causation of human errors and the Freudian slip In psychoanalysis, a Freudian slip, also called parapraxis, is an error in speech, memory, or physical action that occurs due to the interference of an unconscious subdued wish or internal train of thought. Classical examples involve slips of ..., and as a faculty member at the Wright Institute. Baars co-founded the Association for the Scientific Study of Consciousness and the Academic Press journal '' Consciousness and Cognition'', which he also edited, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Priming (psychology)
Priming is a concept in psychology and psycholinguistics to describe how exposure to one stimulus may influence a response to a subsequent stimulus, without conscious guidance or intention. The priming effect is the positive or negative effect of a rapidly presented stimulus (priming stimulus) on the processing of a second stimulus (target stimulus) that appears shortly after. Generally speaking, the generation of priming effect depends on the existence of some positive or negative relationship between priming and target stimuli. For example, the word ''nurse'' might be recognized more quickly following the word ''doctor'' than following the word ''bread''. Priming can be perceptual, associative, repetitive, positive, negative, affective, semantic, or conceptual. Priming effects involve word recognition, semantic processing, attention, unconscious processing, and many other issues, and are related to differences in various writing systems. How quickly this effect occurs is conte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turing Machine
A Turing machine is a mathematical model of computation describing an abstract machine that manipulates symbols on a strip of tape according to a table of rules. Despite the model's simplicity, it is capable of implementing any computer algorithm. The machine operates on an infinite memory tape divided into discrete mathematics, discrete cells, each of which can hold a single symbol drawn from a finite set of symbols called the Alphabet (formal languages), alphabet of the machine. It has a "head" that, at any point in the machine's operation, is positioned over one of these cells, and a "state" selected from a finite set of states. At each step of its operation, the head reads the symbol in its cell. Then, based on the symbol and the machine's own present state, the machine writes a symbol into the same cell, and moves the head one step to the left or the right, or halts the computation. The choice of which replacement symbol to write, which direction to move the head, and whet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artificial Neuron
An artificial neuron is a mathematical function conceived as a model of a biological neuron in a neural network. The artificial neuron is the elementary unit of an ''artificial neural network''. The design of the artificial neuron was inspired by biological neural circuitry. Its inputs are analogous to excitatory postsynaptic potentials and inhibitory postsynaptic potentials at neural dendrites, or . Its weights are analogous to synaptic weights, and its output is analogous to a neuron's action potential which is transmitted along its axon. Usually, each input is separately weighted, and the sum is often added to a term known as a ''bias'' (loosely corresponding to the threshold potential), before being passed through a nonlinear function known as an activation function. Depending on the task, these functions could have a sigmoid shape (e.g. for binary classification), but they may also take the form of other nonlinear functions, piecewise linear functions, or step fun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spiking Neuron
Spiking neural networks (SNNs) are artificial neural networks (ANN) that mimic natural neural networks. These models leverage timing of discrete spikes as the main information carrier. In addition to neuronal and synaptic state, SNNs incorporate the concept of time into their operating model. The idea is that neurons in the SNN do not transmit information at each propagation cycle (as it happens with typical multi-layer perceptron networks), but rather transmit information only when a membrane potential—an intrinsic quality of the neuron related to its membrane electrical charge—reaches a specific value, called the threshold. When the membrane potential reaches the threshold, the neuron fires, and generates a signal that travels to other neurons which, in turn, increase or decrease their potentials in response to this signal. A neuron model that fires at the moment of threshold crossing is also called a spiking neuron model. While spike rates can be considered the analog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Donna Hudson
Donna Lee Hudson (born 1946) is an American biomedical engineer known for her research on expert systems for medical diagnosis and on the application of chaos theory to heart rhythms. She is a professor emerita at the University of California, San Francisco. Education and career Hudson majored in mathematics at California State University, Fresno, graduating in 1968 and began working for Boeing, on computational problems involving wind tunnels. She returned to CSU Fresno for a master's degree in mathematics, which she earned in 1972. In 1975, as a graduate student in engineering and computer science at the University of California, Los Angeles, she began working as an instructor at CSU Fresno. She completed her Ph.D. in 1981, and after completing her Ph.D. took a faculty position at the University of California, San Francisco, affiliated with the Fresno branch campus of the university and with its clinical and translational informatics and bioengineering programs. Hudson was pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noradrenergic
Norepinephrine (NE), also called noradrenaline (NA) or noradrenalin, is an organic chemical in the catecholamine family that functions in the brain and body as a hormone, neurotransmitter and neuromodulator. The name "noradrenaline" (from Latin '' ad'', "near", and '' ren'', "kidney") is more commonly used in the United Kingdom and the rest of the world, whereas "norepinephrine" (from Ancient Greek ἐπῐ́ (''epí''), "upon", and νεφρός (''nephrós''), "kidney") is usually preferred in the United States. "Norepinephrine" is also the international nonproprietary name given to the drug. Regardless of which name is used for the substance itself, parts of the body that produce or are affected by it are referred to as noradrenergic. The general function of norepinephrine is to mobilize the brain and body for action. Norepinephrine release is lowest during sleep, rises during wakefulness, and reaches much higher levels during situations of stress or danger, in the so- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neuromodulation (biology)
Neuromodulation is the physiological process by which a given neuron uses one or more chemicals to regulate diverse populations of neurons. Neuromodulators typically bind to metabotropic, G-protein coupled receptors (GPCRs) to initiate a second messenger signaling cascade that induces a broad, long-lasting signal. This modulation can last for hundreds of milliseconds to several minutes. Some of the effects of neuromodulators include altering intrinsic firing activity, increasing or decreasing voltage-dependent currents, altering synaptic efficacy, increasing bursting activity and reconfiguring synaptic connectivity. Major neuromodulators in the central nervous system include: dopamine, serotonin, acetylcholine, histamine, norepinephrine, nitric oxide, and several neuropeptides. Cannabinoids can also be powerful CNS neuromodulators. Neuromodulators can be packaged into vesicles and released by neurons, secreted as hormones and delivered through the circulatory system. A neuromod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interneuron
Interneurons (also called internuncial neurons, association neurons, connector neurons, or intermediate neurons) are neurons that are not specifically motor neurons or sensory neurons. Interneurons are the central nodes of neural circuits, enabling communication between sensory or motor neurons and the central nervous system (CNS). They play vital roles in reflexes, neuronal oscillations, and neurogenesis in the adult mammalian brain. Interneurons can be further broken down into two groups: local interneurons and relay interneurons. Local interneurons have short axons and form circuits with nearby neurons to analyze small pieces of information. Relay interneurons have long axons and connect circuits of neurons in one region of the brain with those in other regions. However, interneurons are generally considered to operate mainly within local brain areas. The interaction between interneurons allows the brain to perform complex functions such as learning and decision-making. Stru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pyramidal Cell
Pyramidal cells, or pyramidal neurons, are a type of multipolar neuron found in areas of the brain including the cerebral cortex, the hippocampus, and the amygdala. Pyramidal cells are the primary excitation units of the mammalian prefrontal cortex and the corticospinal tract. One of the main structural features of the pyramidal neuron is the conic shaped soma, or cell body, after which the neuron is named. Other key structural features of the pyramidal cell are a single axon, a large apical dendrite, multiple basal dendrites, and the presence of dendritic spines. Pyramidal neurons are also one of two cell types where the characteristic sign, Negri bodies, are found in post-mortem rabies infection. Pyramidal neurons were first discovered and studied by Santiago Ramón y Cajal. Since then, studies on pyramidal neurons have focused on topics ranging from neuroplasticity to cognition. Structure One of the main structural features of the pyramidal neuron is the conic sha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Constantin Von Economo
Constantin Freiherr von Economo (; 21 August 1876 – 21 October 1931) was an Austrian psychiatrist and neurologist of Romanian origin. He is mostly known for his discovery of encephalitis lethargica and his atlas of cytoarchitectonics of the cerebral cortex. Biography Family and schooling Constantin Economo von San Serff was born in Brăila, Romania, to Johannes and Helene Economo, a wealthy family with large holdings in Thessaly and Macedonia. The Economo (Οικονόμου, '' Oikonomou'') family originated from Edessa, in the Ottoman Sanjak of Salonica (modern Edessa, Central Macedonia, Greece) where some of Constantin's ancestors were notables, and his family included many bishops. In 1877, the family moved to Trieste, Austria-Hungary,Economo, K. (1932). ''Constantin Freiherr von Economo''. Wien: Mayer & Co. and Constantin spent his childhood and youth in Trieste. He was a good student, speaking several languages fluently. In 1906, his family was ennobled and E ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalamo-cortico-thalamic Circuits
Thalamo-cortico-thalamic circuits consist of looped neural pathways that connect the thalamus to the cerebral cortex The cerebral cortex, also known as the cerebral mantle, is the outer layer of neural tissue of the cerebrum of the brain in humans and other mammals. It is the largest site of Neuron, neural integration in the central nervous system, and plays ..., and connect the cerebral cortex back to the thalamus. Some researchers propose that such circuits allow the brain to obtain data on its own activity. See also * Recurrent thalamo-cortical resonance Thalamic connections {{neuroanatomy-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
