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List Of Unsolved Problems In Neuroscience
The following is a list of notable unsolved problems in neuroscience. A problem is considered unsolved if no answer is known or if there is significant disagreement among experts about a proposed solution. Consciousness * Consciousness: **How can consciousness be defined? **What is the neural basis of subjective experience, cognition, wakefulness, alertness, arousal, and attention? ***Binding problem: How exactly is it that objects, background, and abstract or emotional features are combined into a single experience? ***What is the neural basis of self? ** Quantum mind: Do quantum mechanical phenomena, such as entanglement and superposition, play an important part in the brain's function and can it explain critical aspects of consciousness? **Is there a "hard problem of consciousness"? ***If so, how is it solved? ***Vertiginous question: Why is it that a specific subject of experience is "live" from a given perspective? **What, if anything, is the function of consciousness ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lists Of Unsolved Problems
List of unsolved problems may refer to several notable conjectures or open problems in various academic fields: Natural sciences, engineering and medicine * Unsolved problems in astronomy * Unsolved problems in biology * Unsolved problems in chemistry * Unsolved problems in geoscience * Unsolved problems in medicine * Unsolved problems in neuroscience * Unsolved problems in physics Mathematics, statistics and information sciences * Unsolved problems in mathematics * Unsolved problems in statistics * Unsolved problems in computer science * Unsolved problems in information theory Social sciences and humanities * Problems in philosophy * Unsolved problems in economics * Unsolved problems in fair division See also * Cold case (unsolved crimes) * List of ciphertexts * List of hypothetical technologies * List of NP-complete problems * List of paradoxes * List of PSPACE-complete problems * List of undecidable problems * List of unsolved deaths This list of unsolved death ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Problem Of Mental Causation
The problem of mental causation is a conceptual issue in the philosophy of mind. That problem, in short, is how to account for the common sense idea that intentional thoughts or intentional mental states are causes of intentional actions. The problem divides into several distinct sub-problems, including the problem of causal exclusion, the problem of anomalism, and the problem of externalism. However, the sub-problem which has attracted most attention in the philosophical literature is arguably the exclusion problem. Description The basic problem of mental causation is an intuitive one: on the face of it, it seems that mental events cause physical events (and vice versa), but how can mental events have any causal effect on physical events? Suppose that a person, John, orders dessert after dinner. It seems that at least one cause for such a physical, behavioral event is that John desired to have dessert and believed that by ordering dessert he would be able to soon have dessert. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Artificial Neural Network
In machine learning, a neural network (also artificial neural network or neural net, abbreviated ANN or NN) is a computational model inspired by the structure and functions of biological neural networks. A neural network consists of connected units or nodes called '' artificial neurons'', which loosely model the neurons in the brain. Artificial neuron models that mimic biological neurons more closely have also been recently investigated and shown to significantly improve performance. These are connected by ''edges'', which model the synapses in the brain. Each artificial neuron receives signals from connected neurons, then processes them and sends a signal to other connected neurons. The "signal" is a real number, and the output of each neuron is computed by some non-linear function of the sum of its inputs, called the '' activation function''. The strength of the signal at each connection is determined by a ''weight'', which adjusts during the learning process. Typically, ne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Connectionism
Connectionism is an approach to the study of human mental processes and cognition that utilizes mathematical models known as connectionist networks or artificial neural networks. Connectionism has had many "waves" since its beginnings. The first wave appeared 1943 with Warren Sturgis McCulloch and Walter Pitts both focusing on comprehending neural circuitry through a formal and mathematical approach, and Frank Rosenblatt who published the 1958 paper "The Perceptron: A Probabilistic Model For Information Storage and Organization in the Brain" in ''Psychological Review'', while working at the Cornell Aeronautical Laboratory. The first wave ended with the 1969 book about the limitations of the original perceptron idea, written by Marvin Minsky and Seymour Papert, which contributed to discouraging major funding agencies in the US from investing in connectionist research. With a few noteworthy deviations, most connectionist research entered a period of inactivity until the mid-1980 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Model Of Computation
In computer science, and more specifically in computability theory and computational complexity theory, a model of computation is a model which describes how an output of a mathematical function is computed given an input. A model describes how units of computations, memories, and communications are organized. The computational complexity of an algorithm can be measured given a model of computation. Using a model allows studying the performance of algorithms independently of the variations that are specific to particular implementations and specific technology. Categories Models of computation can be classified into three categories: sequential models, functional models, and concurrent models. Sequential models Sequential models include: * Finite-state machines * Post machines ( Post–Turing machines and tag machines). * Pushdown automata * Register machines ** Random-access machines * Turing machines * Decision tree model * External memory model Functional models Functio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Formal System
A formal system is an abstract structure and formalization of an axiomatic system used for deducing, using rules of inference, theorems from axioms. In 1921, David Hilbert proposed to use formal systems as the foundation of knowledge in mathematics. The term ''formalism'' is sometimes a rough synonym for ''formal system'', but it also refers to a given style of notation, for example, Paul Dirac's bra–ket notation. Concepts A formal system has the following: * Formal language, which is a set of well-formed formulas, which are strings of symbols from an alphabet, formed by a formal grammar (consisting of production rules or formation rules). * Deductive system, deductive apparatus, or proof system, which has rules of inference that take axioms and infers theorems, both of which are part of the formal language. A formal system is said to be recursive (i.e. effective) or recursively enumerable if the set of axioms and the set of inference rules are decidable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computational Theory Of Mind
In philosophy of mind, the computational theory of mind (CTM), also known as computationalism, is a family of views that hold that the human mind is an information processing system and that cognition and consciousness together are a form of computation. It is closely related to functionalism, a broader theory that defines mental states by what they do rather than what they are made of. Warren McCulloch and Walter Pitts (1943) were the first to suggest that neural activity is computational. They argued that neural computations explain cognition. The theory was proposed in its modern form by Hilary Putnam in 1960 and 1961, and then developed by his PhD student, philosopher, and cognitive scientist Jerry Fodor in the 1960s, 1970s, and 1980s.Horst, Steven, (2005"The Computational Theory of Mind"in ''The Stanford Encyclopedia of Philosophy'' It was later criticized in the 1990s by Putnam himself, John Searle, and others. The computational theory of mind holds that the human mind is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayesian Probability
Bayesian probability ( or ) is an interpretation of the concept of probability, in which, instead of frequency or propensity of some phenomenon, probability is interpreted as reasonable expectation representing a state of knowledge or as quantification of a personal belief. The Bayesian interpretation of probability can be seen as an extension of propositional logic that enables reasoning with hypotheses; that is, with propositions whose truth or falsity is unknown. In the Bayesian view, a probability is assigned to a hypothesis, whereas under frequentist inference, a hypothesis is typically tested without being assigned a probability. Bayesian probability belongs to the category of evidential probabilities; to evaluate the probability of a hypothesis, the Bayesian probabilist specifies a prior probability. This, in turn, is then updated to a posterior probability in the light of new, relevant data (evidence). The Bayesian interpretation provides a standard set of procedur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bayesian Approaches To Brain Function
Bayesian approaches to brain function investigate the capacity of the nervous system to operate in situations of uncertainty in a fashion that is close to the optimal prescribed by Bayesian statistics. This term is used in behavioural sciences and neuroscience and studies associated with this term often strive to explain the brain's cognitive abilities based on statistical principles. It is frequently assumed that the nervous system maintains internal probabilistic models that are updated by neural processing of sensory information using methods approximating those of Bayesian probability. Origins This field of study has its historical roots in numerous disciplines including machine learning, experimental psychology and Bayesian statistics. As early as the 1860s, with the work of Hermann Helmholtz in experimental psychology, the brain's ability to extract perceptual information from sensory data was modeled in terms of probabilistic estimation. The basic idea is that the nervous sy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mind
The mind is that which thinks, feels, perceives, imagines, remembers, and wills. It covers the totality of mental phenomena, including both conscious processes, through which an individual is aware of external and internal circumstances, and unconscious processes, which can influence an individual without intention or awareness. The mind plays a central role in most aspects of human life, but its exact nature is disputed. Some characterizations focus on internal aspects, saying that the mind transforms information and is not directly accessible to outside observers. Others stress its relation to outward conduct, understanding mental phenomena as dispositions to engage in observable behavior. The mind–body problem is the challenge of explaining the relation between matter and mind. Traditionally, mind and matter were often thought of as distinct substances that could exist independently from one another. The dominant philosophical position since the 20th century has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mental Representation
A mental representation (or cognitive representation), in philosophy of mind, cognitive psychology, neuroscience, and cognitive science, is a hypothetical internal cognitive symbol that represents external reality or its abstractions. Mental representation is the mental imagery of things that are not actually present to the senses. In contemporary philosophy, specifically in fields of metaphysics such as philosophy of mind and ontology, a mental representation is one of the prevailing ways of explaining and describing the nature of ideas and concepts. Mental representations (or mental imagery) enable representing things that have never been experienced as well as things that do not exist. Our brains and mental imageries allow us to imagine things have either never happened or are impossible and do not exist. Although visual imagery is more likely to be recalled, mental imagery may involve representations in any of the sensory modalities, such as hearing, smell, or taste. S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Philosophical Zombie
A philosophical zombie (or "p-zombie") is a being in a thought experiment in the philosophy of mind that is physically identical to a normal human being but does not have conscious experience. For example, if a philosophical zombie were poked with a sharp object, it would not feel any pain, but it would react exactly the way any conscious human would. Philosophical zombie arguments are used against forms of physicalism and in defense of the hard problem of consciousness, which is the problem of accounting in physical terms for subjective, intrinsic, first-person, what-it's-like-ness experiences. Proponents of philosophical zombie arguments, such as the philosopher David Chalmers, argue that since a philosophical zombie is by definition physically identical to a conscious person, even its logical possibility refutes physicalism. This is because it establishes the existence of conscious experience as a further fact.Chalmers, D. (1996): The Conscious Mind, Oxford University Pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
