2019-07-neuron How do neurons process information? Neurons are known to break down an incoming electrical signal into sub-units. Now, researchers at Blue Brain have discovered that dendrites, the neuron's tree-like receptors, work together—dynamically and depending on the workload—for learning. In a paper published in the journal Cell Reports, researchers at EPFL's Blue Brain Project, a Swiss Brain Research Initiative, have developed a new framework to work out how a single neuron in the brain operates. The analysis was performed using cells from the Blue Brain's virtual rodent cortex. Their results show that when a neuron receives input, the branches of the elaborate tree-like receptors extending from the neuron, known as dendrites, functionally work together in a way that is adjusted to the complexity of the input. The strength of a synapse determines how strongly a neuron feels an electric signal coming from other neurons, and the act of learning changes this strength. More information: Willem A.M.
www.brainfacts Cells within the nervous system, called neurons, communicate with each other in unique ways. The neuron is the basic working unit of the brain, a specialized cell designed to transmit information to other nerve cells, muscle, or gland cells. Neurons are cells within the nervous system that transmit information to other nerve cells, muscle, or gland cells. Most neurons have a cell body, an axon, and dendrites. Illustration by Lydia V. The brain is what it is because of the structural and functional properties of interconnected neurons. The cell body contains the nucleus and cytoplasm. Dendrites extend from the neuron cell body and receive messages from other neurons. When neurons receive or send messages, they transmit electrical impulses along their axons, which can range in length from a tiny fraction of an inch (or centimeter) to three feet (about one meter) or more. The brain contains at least ten times more glia than neurons.
040616064016 Researchers from USC and the Technion Medical School in Israel have uncovered new clues into the mystery of the brain's ultra-complicated cells known as neurons. Their findings -- appearing in this month's issue of the journal Nature Neuroscience -- contradict a widely accepted idea regarding the "arithmetic" neurons use to process information. "It's amazing that after a hundred years of modern neuroscience research, we still don't know the basic information processing functions of a neuron," said Bartlett Mel, an associate professor in the USC Viterbi School of Engineering and contributing author of the journal's article. "For lack of a better idea, it has always been thought that a brain cell sums up its excitatory inputs linearly, meaning that the excitation caused by two inputs A and B activated together equals the sum of excitations caused by A and B presented separately." "We show that the cell significantly violates that rule," Mel said.
pt.m.wikipedia Sinapses são zonas ativas de contato entre uma terminação nervosa e outros neurônios, células musculares ou células glandulares. Do ponto de vista anatômico e funcional, uma sinapse é composta por três grandes compartimentos: membrana da célula pré-sináptica, fenda sináptica e membrana pós-sináptica. Os principais tipos de contato sináptico são: axo-somático (entre um axônio e o corpo celular), axo-dendrítico (entre um axônio e um dendrito), neuroefetor (entre a terminação nervosa e a célula efetora, fibra muscular lisa, fibra muscular cardíaca ou célula glandular), neuromuscular (entre a terminação nervosa e a fibra muscular esquelética).[1] Os neurônios nas sinapses[editar | editar código-fonte] As células nervosas diferenciam-se das demais células do organismo por apresentarem duas propriedades especiais: Os neurônios dispõe-se em cadeias celulares de transmissão e processamento de informações. Tipos de sinapse[editar | editar código-fonte] Essas quatro funções são: Referências
www.wingsforlife 2013-11-13 Back to overview Wings for Life will regularly publish “illustration guides” designed to help non-scientists understanding how the spinal cord works, how the injury alters it and finally which different approaches scientists are taking to find a cure for spinal cord injury. The first illustration guide will explore the basic structure and functioning of a neuron. Basic principle A neuron (also known as nerve cell) is an electrically excitable cell that takes up, processes and transmits information through electrical and chemical signals. In order that a human being can react to his environment, neurons transport stimuli. A simple structure designed for a complex task A typical neuron is divided into three parts: the cell body, the dendrites and the axon. To make a comparable scale, the diameter of a neuron is about the tenth size of the diameter of a human hair. Getting really into it The cell body is the central part of the neuron. Transmitting information
www.todamateria.com Sinapse é a região localizada entre neurônios onde agem os neurotransmissores (mediadores químicos), transmitindo o impulso nervoso de um neurônio a outro, ou de um neurônio para uma célula muscular ou glandular. Neurotransmissores transmitindo o sinal entre neurônios O que são Sinapses? As sinapses são junções entre a terminação de um neurônio e a membrana de outro neurônio. São elas que fazem a conexão entre células vizinhas, dando continuidade à propagação do impulso nervoso por toda a rede neuronal. Os neurônios fazem a comunicação entre os órgãos do corpo e o meio externo, isso acontece através de sinais elétricos. Representação da sinapse O espaço entre as membranas das células é chamado fenda sináptica. Como Ocorrem as Sinapses? Geralmente a sinapse ocorre entre o axônio de um neurônio e o dendrito do neurônio seguinte, mas também pode ocorrer do axônio diretamente para o corpo celular, ou entre do axônio do neurônio para uma célula muscular. Tipos de Sinapses Sinapses Químicas
o-que-e-sinapse Sabemos que os impulsos nervosos devem passar de uma célula à outra para que ocorra uma resposta a um determinado sinal. Para que isso ocorra, é necessária a presença de uma região especializada, que recebe o nome de sinapse. Ela pode ser definida como a região de proximidade entre a extremidade de um neurônio e uma célula vizinha, onde os impulsos nervosos são transformados em impulsos químicos em decorrência da presença de mediadores químicos. Um neurônio faz sinapses com diversos outros neurônios. Os axônios apresentam diversas ramificações e, no final delas, são encontradas expansões chamadas de botões pré-sinápticos. Não pare agora... No botão pré-sináptico existem diversas mitocôndrias, além de vesículas que são repletas de uma substância química que recebe o nome de neurotransmissores, que são capazes de alterar a permeabilidade da membrana do neurônio pós-sináptico. Quando um impulso nervoso chega ao botão pré-sináptico, os neurotransmissores são liberados na fenda sináptica.
en.m.wikipedia Cryptanalytic method for unauthorized users to access data A brute-force attack is a cryptanalytic attack that can, in theory, be used to attempt to decrypt any encrypted data (except for data encrypted in an information-theoretically secure manner). Such an attack might be used when it is not possible to take advantage of other weaknesses in an encryption system (if any exist) that would make the task easier. When password-guessing, this method is very fast when used to check all short passwords, but for longer passwords other methods such as the dictionary attack are used because a brute-force search takes too long. Longer passwords, passphrases and keys have more possible values, making them exponentially more difficult to crack than shorter ones due to diversity of characters.[3] Brute-force attacks are an application of brute-force search, the general problem-solving technique of enumerating all candidates and checking each one. Credential recycling [edit] Reverse brute-force attack
2 Sinapse é um tipo de junção especializada em que um terminal axonal faz contato com outro neurônio ou tipo celular. As sinapses podem ser elétricas ou químicas (maioria). Sinapses elétricas As sinapses elétricas, mais simples e evolutivamente antigas, permitem a transferência direta da corrente iônica de uma célula para outra. Imagem: BEAR, M.F., CONNORS, B.W. & PARADISO, M.A. Em invertebrados, as sinapses elétricas são comumente encontradas em circuitos neuronais que medeiam respostas de fuga. Sinapses químicas Via de regra, a transmissão sináptica no sistema nervoso humano maduro é química. Como o citoplasma dos axônios, inclusive do terminal axonal, não possui ribossomos, necessários à síntese de proteínas, as proteínas axonais são sintetizadas no soma (corpo celular), empacotadas em vesículas membranosas e transportadas até o axônio pela ação de uma proteína chamada cinesina, a qual se desloca sobre os microtúbulos, com gasto de ATP. Imagem: CÉSAR & CEZAR. 1. 2. 3. Sinapses elétricas
X 24th letter of the Latin alphabet History Pronunciation and use English In English orthography, ⟨x⟩ is typically pronounced as the voiceless consonant cluster when it follows the stressed vowel (e.g. ox), and the voiced consonant when it precedes the stressed vowel (e.g. exam). There are very few English words that start with ⟨x⟩ (the fewest of any letter). X is the third least frequently used letter in English (after ⟨q⟩ and ⟨z⟩), with a frequency of about 0.15% in words.[4] Other languages In Latin, ⟨x⟩ stood for [ks]. Additionally, in languages for which the Latin alphabet has been adapted only recently, ⟨x⟩ has been used for various sounds, in some cases inspired by European usage, but in others, for consonants uncommon in Europe. Other systems In the International Phonetic Alphabet, ⟨x⟩ represents a voiceless velar fricative. Other uses On some identification documents, the letter X represents a non-binary gender, where F means female and M means male.[7][8] Related characters Computing
www.bloomberg Photographer: David Paul Morris/Bloomberg Google wants to set the standard on artificial intelligence. The Web company, seeking to influence how people design, test, and run artificial-intelligence systems, is making its internal AI development software available for free. The Alphabet Inc.-subsidiary is releasing a program called TensorFlow as freely available open-source software, it said Monday. It’s based on the same internal system Google has spent several years developing to support its AI software and other mathematically complex programs. Artificial intelligence enables products such as personal assistants, including Google Now and Microsoft’s Cortana. The release of TensorFlow means anyone can download and modify the development software that underpins RankBrain, the AI powering part of Google’s search engine and new features such as its Smart Reply e-mail tool, Google wrote in a blog post. The companies are also trying guide AI development.
observer Neural networks enable machines to “learn.” (Photo: Pixabay) It’s easy to make the case that Google is at the forefront of artificial intelligence research. Their Neural Turing Machine can essentially program itself, and they’ve acquired DeepMind Technologies, a lab that has repeatedly made headlines for their AI advancements. We wanted to find out what the company is up to now and how their current research will play into the technology we use every day, specifically Google’s own services. Speech recognition When you talk to Siri or any other speech-to-text feature of your phone, all it’s doing is transcribing what you say. Natural language and search Language was a big topic because it plays such an important role in so many facets of AI research. This AI computer outperformed humans on an IQ test Mr. Basically, the neural network is building up this space of words with information on how they’re used in the real world, what they mean and how frequently they appear together. Mr.
www.zdnet What is artificial general intelligence? An Artificial General Intelligence (AGI) would be a machine capable of understanding the world as well as any human, and with the same capacity to learn how to carry out a huge range of tasks. AGI doesn't exist, but has featured in science-fiction stories for more than a century, and been popularized in modern times by films such as 2001: A Space Odyssey. Fictional depictions of AGI vary widely, although tend more towards the dystopian vision of intelligent machines eradicating or enslaving humanity, as seen in films like The Matrix or The Terminator. In contrast, utopian imaginings, such as Iain M Banks' Culture civilization novels, cast AGI as benevolent custodians, running egalitarian societies free of suffering, where inhabitants can pursue their passions and technology advances at a breathless pace. What could an artificial general intelligence do? Could an artificial general intelligence outsmart humans? What is superintelligence? Vyacheslav W.
How Far Are We From Achieving Artificial General Intelligence? These days, when you browse the internet for news on artificial intelligence, you’ll find out about new AI that just managed to do something humans do, yet far better. Present day AI can detect cancers better than human doctors, build better AI algorithms than human developers, and beat the world champions at games like chess and Go. Instances like these may lead us to believe that perhaps, there’s not a whole lot that artificial intelligence can not do better than us humans. While the debate on whether the development of artificial general intelligence or artificial superintelligence is promising or pernicious rages on, the jury on when such advanced forms of AI will come into existence is also still out. What is the current state of artificial intelligence? Allerin The internet abounds with stories of stunning applications that exist today, culminating from years of artificial intelligence research. What exactly is artificial general intelligence?