What is Neural: Definition and 105 Discussions

In biology, the nervous system is a highly complex part of an animal that coordinates its actions and sensory information by transmitting signals to and from different parts of its body. The nervous system detects environmental changes that impact the body, then works in tandem with the endocrine system to respond to such events. Nervous tissue first arose in wormlike organisms about 550 to 600 million years ago. In vertebrates it consists of two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS consists of the brain and spinal cord. The PNS consists mainly of nerves, which are enclosed bundles of the long fibers or axons, that connect the CNS to every other part of the body. Nerves that transmit signals from the brain are called motor nerves or efferent nerves, while those nerves that transmit information from the body to the CNS are called sensory nerves or afferent. Spinal nerves are mixed nerves that serve both functions. The PNS is divided into three separate subsystems, the somatic, autonomic, and enteric nervous systems. Somatic nerves mediate voluntary movement. The autonomic nervous system is further subdivided into the sympathetic and the parasympathetic nervous systems. The sympathetic nervous system is activated in cases of emergencies to mobilize energy, while the parasympathetic nervous system is activated when organisms are in a relaxed state. The enteric nervous system functions to control the gastrointestinal system. Both autonomic and enteric nervous systems function involuntarily. Nerves that exit from the cranium are called cranial nerves while those exiting from the spinal cord are called spinal nerves.
At the cellular level, the nervous system is defined by the presence of a special type of cell, called the neuron, also known as a "nerve cell". Neurons have special structures that allow them to send signals rapidly and precisely to other cells. They send these signals in the form of electrochemical impulses traveling along thin fibers called axons, which can be directly transmitted to neighboring cells through electrical synapses or cause chemicals called neurotransmitters to be released at chemical synapses. A cell that receives a synaptic signal from a neuron may be excited, inhibited, or otherwise modulated. The connections between neurons can form neural pathways, neural circuits, and larger networks that generate an organism's perception of the world and determine its behavior. Along with neurons, the nervous system contains other specialized cells called glial cells (or simply glia), which provide structural and metabolic support.
Nervous systems are found in most multicellular animals, but vary greatly in complexity. The only multicellular animals that have no nervous system at all are sponges, placozoans, and mesozoans, which have very simple body plans. The nervous systems of the radially symmetric organisms ctenophores (comb jellies) and cnidarians (which include anemones, hydras, corals and jellyfish) consist of a diffuse nerve net. All other animal species, with the exception of a few types of worm, have a nervous system containing a brain, a central cord (or two cords running in parallel), and nerves radiating from the brain and central cord. The size of the nervous system ranges from a few hundred cells in the simplest worms, to around 300 billion cells in African elephants.The central nervous system functions to send signals from one cell to others, or from one part of the body to others and to receive feedback. Malfunction of the nervous system can occur as a result of genetic defects, physical damage due to trauma or toxicity, infection, or simply senesence. The medical specialty of neurology studies disorders of the nervous system and looks for interventions that can prevent or treat them. In the peripheral nervous system, the most common problem is the failure of nerve conduction, which can be due to different causes including diabetic neuropathy and demyelinating disorders such as multiple sclerosis and amyotrophic lateral sclerosis. Neuroscience is the field of science that focuses on the study of the nervous system.

View More On Wikipedia.org
  1. A

    Neural networks as mathematical models of intelligence

    Why do almost all people not think that neural networks are the mathematical model of intelligence? I briefly explain what I understand: -A neuron is a mathematical object that takes numerical inputs from other nearby neurons, applies a nonlinear function (combining the input with numbers...
  2. V

    Mathematica Neural networks in Wolfram Mathematica

    Hello, I have a question about the use of functions and overall creation of neural networks in the Wolfram Mathematica (WM) program. I wonder if it is realistic to make meaningful neural networks usable at least partially for scientific research in WM? By scientific research, I do not mean the...
  3. Superposed_Cat

    Debugging a Backprop Neural Network: Issues & Solutions

    I am trying for the first time in 5 years, to make a n- layer, m-width backprop neural network from scratch, My issue is, I've tried training it on XOR, where it returns 0.48 for any of the inputs instead of 1 for half of them and 0 for the other half, if you give it a dataset where the outputs...
  4. M

    A Mixture density neural network prediction bias

    Hello! I am using a mixture density network (MDN) to make some predictions. My model is very simple with one hidden layer only with 10 nodes (the details of the network shouldn't matter for my question but I can provide more if needed). Also my MDN has only one gaussian component which basically...
  5. B

    Deep learning - neural network

    I have a picture of a guy's face and I had an artist draw him as an alien. How do I make a neural network that would take in the original picture and learn how to draw the picture the that artist make? I want to make a filter, that if you can enter in any guy's face, and the program would...
  6. M

    MHB Neural Networks : Which stock has the biggest increase ?

    Hey! 😊 On 20.06.2022 we have 1 million dollars for 10 days, so until 30.06.2022, and we want to increase the capital through shares. (The data of the shares can be found on finance.yahoo.com) So we want to check which stock has the biggest increase in this period. So we have to use the...
  7. B

    Python Input error for LSTM neural network

    Hi everyone, I have to classify a DNA sequence with a LSTM neural network but I have a problem with the inputs shame. Both the sequence and the class are encoded with One Hot Encoding and my code is this: import pandas as pd import numpy as np data = pd.read_csv('splice.data', header = None)...
  8. Borg

    Python Understanding Graph Neural Networks (GNNs) Tutorials & Examples

    I've been reading various articles on Graph Neural Networks (GNNs) for the last month or so. In particular, I have been focusing on the tutorials in A Blitz Introduction to DGL. I made it through all of the tutorials OK but I'm having trouble understanding certain aspects of GNNs. I'm also...
  9. shivajikobardan

    Comp Sci Confusions about Hopfield neural networks -- Questions about this solved example

    I am from Nepal and instead of asking us code, these are types of questions that are asked in our country examination system. IDK what's their purpose. But some of them are badly hard as there are not many examples about it in textbook(In Nepal we can't get the textbook reference that the...
  10. shivajikobardan

    MHB Confusions about hopfield neural network solved example

    I am from Nepal and instead of asking us code, these are types of questions that are asked in our country examination system. IDK what's their purpose. But some of them are badly hard as there are not many examples about it in textbook(In Nepal we can't get the textbook reference that the...
  11. user366312

    How can I implement a multi-task deep learning neural network?

    I have 3 classes (A, B, and C). I have 6 features: train_x = [[ 6.442 6.338 7.027 8.789 10.009 12.566] [ 6.338 7.027 5.338 10.009 8.122 11.217] [ 7.027 5.338 5.335 8.122 5.537 6.408] [ 5.338 5.335 5.659 5.537 5.241 7.043]] These features...
  12. F

    Understanding Convolutional Neural Networks with CNNs

    Hello, I have been learning about convolutional neural networks (CNNs) recently and wonder if I could get some help with a specific question: Assume we start with an input grayscale image having size NxN pixels. The image is passed to the 1st convolutional layer which has 3 filters (kernels) of...
  13. S

    Prob/Stats Any good math-theory-focused books on neural networks and data science?

    Hi. I'm looking for books on data science, preferably leaning towards neural networks, that focus on mathematical rigor. For example, theorems on optimization, minimum number of layers to accomplish a task efficiently, etc. Most books I've seen seem to hand wave this stuff. Anyone know any juicy...
  14. Z

    Why is my multilayered, feedforward neural network not working?

    Hey, guys. So, I've developed a basic multilayered, feedforward neural network from scratch in Python. However, I cannot for the life of me figure out why it is still not working. I've double checked the math like ten times, and the actual code is pretty simple. So, I have absolutely no idea...
  15. S

    Neural network without neurotransmitters

    Could evolution have produced neural network without chemical neurotransmitter (such as serotonin), like our computers? Are their organisms without neurotansmitters? If neurotransmitter are indispensable. Why don't our computers have components or function similar to neurotransmitters?
  16. S

    Thoughts on neural networks "discovering" physical concepts

    (sorry i post this here now because i didn't know about this sub forum earlier) I came across an interesting paper from which I'll quote parts of the intro: and the conclusion: obviously the authors are more competent in Physics than I am - so are most PF member. what are your opinions on...
  17. S

    Thoughts on neural networks "discovering" physical concepts

    I came across an interesting paper from which I'll quote parts of the intro: and the conclusion: obviously the authors are more competent in Physics than I am - so are most PF member. what are your opinions on this? can the work of these authors "discover" physical laws in any way or is the...
  18. S

    Applied Maths of Neural Networks -- books and papers?

    Does anyone know any good up to date books on the mathematics of neural networks? If you know any good research papers that would be cool too. I've read through "Intro to the theory of neural computation" by John Hertz but it's a 1991 book. I'm looking for generalized theorems on...
  19. T

    Combining feature vectors for a neural network

    Let's consider this scenario. I have two conceptually different video datasets, for example a dataset A composed of videos about cats and a dataset B composed of videos about houses. Now, I'm able to extract a feature vectors from both the samples of the datasets A and B, and I know that, each...
  20. P

    Neural Networks Question about the Hebbs and Delta Rule

    Good afternoon, I am currently working on Neural Networks and I am reading an introduction by Jeff Heaton (Neural Networks in Java). Now there are two tasks there whose solutions interest me. The first task is about applying the Hebbs rule. In the book it is given wrong because of a typo but I...
  21. scottdave

    Extending Neural Networks to higher dimensions (article)

    Neural networks have come a long way since I first took a course, 25 years ago. Now that I'm in the Online Masters in Analytics program at Georgia Tech, I see these topics come up often. I found the following article an interesting read...
  22. V

    Mathematica Can Python and R be used for data science techniques?

    Hello, I use Wolfram Mathematica (WM) for my calculation but I'm not much familiar with neural networks, machine learning, etc. On the other hand, I know that WM includes such tools. I would like to learn this stuff just for operating on this level. I read some tutorials and I would like to...
  23. K

    Normalization condition with a neural network

    Hello! I have some data points generated from an unknown distribution (say a 1D Gaussian for example) and I want to build a neural network able to approximate the underlaying distribution i.e. for any given ##x## as input to the neural network, I want the output to be as close as possible to...
  24. E

    Cathodal vs Anodal Electrical Stimulation

    Hello everyone, I am studying at the moment electrical stimulation of nerve fibers. I encountered this image which compares cathodal and anodal stimulation but illustrating the anodal block ocurring with cathode current. But I don't really get the point of the image, could someone clarify it...
  25. D

    Programs Diploma thesis - Neural Network Application in Physical Problems

    Hello everybody. I am currently on my last year of Computational Physics education. More and more I am interested in Machine Learning and Neural Network. Time has come for me to choose diploma work thesis, so I am searching for interesting ideas where I can merge my interest in neural networks...
  26. D

    Neural Networks -- using the NN classifier as the fitness function

    Let's say you've trained a neural network and it can classify cat images with good (90%) accuracy. Now let's say you use a genetic algorithm and start 'breeding' images together using the NN classifier as the fitness function. Will you eventually start generating pictures that look like cats?
  27. V

    Neural networks - uses in Physics and Astrophysics?

    Hello, I'm not very familiar with neural networks, but it seems very interesting. I would like to ask how may I use it in physics, especially in astrophysics? I guess for some data mining? But could anyone show some concrete example of what it can do with data? Or if there is anything else...
  28. Eagle9

    Programs Artificial neural network(s) and Computational neuroscience

    Hello guys :oldeyes: I need your help in order to clarify the following issue :oldsmile: I am PhD student in neuroscience and I am dealing with brain’s neuroanatomy and physiology in case of Autism. But I am more interested in Computational neuroscience, Artificial neural network(s), the...
  29. S

    Neural Nets in AI: What's the Intelligent Part?

    Hello! I learned today about neural/deep nets, convolutional nets and things related to this. I am not sure I understand why is this considered AI. The ideas behind are really beautiful, but in the end there are just better (faster) ways of taking derivatives, which anyone can do once given the...
  30. BWV

    I Neural Networks vs Traditional Numerical Methods

    As neural networks are 'universal approximators' for nonlinear functions, in general how do they perform in comparison to traditional numerical methods for nonlinear PDEs? Just googling, I can find papers on applications to Navier Stokes and other problems, but I don't really have the...
  31. BWV

    Has anyone tried to train a neural network to learn physics?

    Have been curious about a thought experiment where, given enough experimental data to train, a sophisticated enough neural network / deep learning program could 'discover' most of classical and quantum physics. Any thoughts?
  32. ChrisVer

    Python Neural Network training BUT testing fails

    Hi, I was trying to work on a basic NN training problem I found online. The pattern of data to train are the triplets: [101]->1 , [011]->1, [001]->0 , [111]->0 , [100]->1 Meaning that the 3rd number brings no info, while for the first 2 if they are identical it should evaluate to 0 else to 1...
  33. S

    Fraunhofer diffraction experiment- neural density filters

    I'm currently carrying out an experiment with Fraunhofer diffraction. It involves shining a laser beam through neural density filters, a lens and a diffraction grating, to create a diffraction pattern which is then picked up with a CCD camera, to find the intensity of the maximal peaks. However...
  34. ADDA

    Does this ANN make Benjamins?

    I'm attempting to use a artificial neural network to store a fuzzy floating point variable. While writing the code, I became somewhat creative. I used the idea of an Set Reset Latch and statistically translated the hardware SR-latch into an artificial neural network. My mathematical goal is to...
  35. I

    Is action potential a signal transduction?

    This might be either an obvious one, or I might be totally off track. I haven't seen, or been able to find neural action potentials being referenced as signal transductions. Aren't they signal transductions? And if not (say if action potential is only referenced to the change in potential)...
  36. O

    Medical Exploring the Neural Correlates of Emotions: A Scientific Approach

    What are the neural correlates of emotions? Is the neural correlate of emotion the same as the qualia of emotions? What is the latest research about this in the medical and neuroscience field?
  37. E

    Convolution Neural Network

    Hi I am using a convolution neural network (with inversion) to simulate images with the same "texture" as the input image, using a random image to start with. The activations of the CNN are first learned with an example or source image. A cost function then minimizes the difference between the...
  38. B

    Aware of being aware neural circuits

    What is the latest technology update on making circuits aware of being aware.. this is to enable understanding of how our neutral circuits are aware of being aware.. what is the most accepted theory about this? Is it Re-entrant loops in the brain?
  39. 2

    Other Neural networks and genetic algorithms

    Hi. First of all, I am a beginner when it comes to NN and GA. I have a good enough math background though. Could anyone suggest me a good book that covers these topics in an intermediate level? Obviously a very in-depth coverage is hard to expect but I would like something more than a few pages...
  40. 2

    Neural networks and the derivatives of the cost function

    Hello. I need some guidance on the derivation of the derivatives of the quadratic cost function (CF) in an artificial neural network. I can derive the equations for the forward propagation with no trouble but when it comes to finding the derivative of the CF with respect to the weight matrix...
  41. T

    Prob/Stats What Are the Best Resources for Learning About Neural Networks?

    Hello, Can you recommend me a book on neural networks, for a beginner in this area? I would like a book that explains the mathematics behind NN's, while still going into computational matters in a package like Matlab. My background is Physics/Maths in Bsc level. Thanks.
  42. G

    Can Neurons Truly Explain the Experience of Red and Other Qualia?

    So how do neural patterns give rise to images.. what's the latest on this? My background is Antonio Damasio's and Edelman's.
  43. arnesinnema

    Can Pi be predicted by a neural network?

    Hi all, Would it be possible to try to predict Pi by a neural net. So basically when you input 1 into the neural net you will train it to output 3. Next input 2 and train it to ouput 1. Etc... Next after training the net such that it will predict the first 1000 positions correctly would it...
  44. Avatrin

    Can artificial intelligence create music?

    Hi What approach should I take if I want to try this with music? I know the mathematics that are needed to learn neural networks (from what I have read on websites like Coursera). Also, I know basic scientific programming with Python. I am willing to spend time to learn how to make the...
  45. B

    A problem regarding neural pathways and OCD

    So let me start by saying I do have clinically diagnosed OCD I take medication for it and have a therapist, its a constant struggle but generally I am able to overcome my ocd's through logic and reasoning but this time I'm stuck in a rut and hope that maybe someone with a neuroscience background...
  46. ShayanJ

    Alzheimer's disease in neural networks

    After watching "Still Alice"(starring Juliane Moore) which is about an Alzheimer's patient, I started thinking about this disease a little bit and suddenly it occurred to me that its plausible to expect seeing such an effect in neural networks too. I mean, imagine you have a neural network that...
  47. N

    Optical Character Recognition using Neural network

    Hey all, does anyone know a link where I can find a c# implementation of a neural net that does OCR WITHOUT using libraries, I feel that OCR is a nice way to learn how neural nets classify data. Any help appreciated, thanks.
  48. N

    Neural Net to play tic-tac-toe

    Hey all, have been playing with genetic algorithms and neural networks(backpropagated ones) recently. Was wondering if anyone had any links to a tic-tac-toe playing neural net in c#. or any suggestion about how to go about doing it. Any help appreciated.
  49. gracy

    Neural Tube vs Dorsal Nerve Cord: What's the Difference?

    Difference between neural tube and dorsal nerve cord?
  50. N

    Question on Neural network transplant ?

    Hello I'm new here as you can tell by my username and I had a question on some research I'm doing. Now it is common knowledge that brain cells and even whole neural network can be transplanted. But my question is on the neural networks. Like for example I was reading that sxuality is determined...
Back
Top