Welcome to the third week of Artificial Intelligence for beginners. Last week you have learnt machine language and project cycle. And in the first week, you have learnt about the neural network and artificial intelligence and how neural network and machine language is a tool for artificial intelligence. This week, we are going to see what is a neural network, how it works in human being, how we can replicate it for an artificial neural network. And finally we will be learning what is deep learning and what is the purpose of deep learning.
In this video, we are going to see how the neural network works in human beings. For that we should learn about the nervous system in our body. The nervous system has brain, spinal cord and the whole body, nerves are connected. This nervous system has been divided into two parts: one is the central nervous system; another one is peripheral nervous system. Central nervous system has the brain and the spinal cord. The nerves which are present in all other parts belong to peripheral nervous system.
Let me explain to you how this system functions then we will be able to learn about the basic unit of the nervous system that is called neuron. Take for example, there is a hot pot in front of me. I am putting my finger on that. Immediately I am pulling my finger out. Now when I am placing this finger, what happens is – I am putting my finger on that, immediately I am pulling my finger out. Now when I am placing this finger, what happens is - my sense organ – it is nothing but my skin- it senses the heat produced by that or heat hurt the finger – that sense has been sent to the brain, okay? – there it is processed and the instruction is given to the muscle in my hand to pull it out.
Immediately I am pulling it out. This happens within a fraction of a second because my brain and fingers has been connected by a network of neuron. What are the neurons involved in the process? First, when I am putting my finger, there is a neuron which is sensing the heat. That is called sensory neuron. Next one, it is sending this to the brain where in the brain a set of neurons are processing that is called interneuron. Then, after processing it, it is sending the message through the motor neurons which instruct the muscles to pull it back. So therefore, there are three types of neurons involved in this. Sensory neuron, which senses and send and motor neurons, which get the instructions and take action, and another important neuron which is present in the brain is called interneuron. It not only process the data but it also stores it for the future use.
Sensory neurons and motor neurons are present in our peripheral nervous system and the interneuron which is processing is central nervous system. Our central nervous system – brain and the spinal cord is acting like a head office and all other peripherals are branches to it. This central office, acting like a central processing unit of the computer is connected with the peripherals – our hands and all parts of the body with a neural network. This neural network is made up of small neurons. There are billions of neurons and billions of neurons, connected together to make a network. We will see how this neuron is working and how it is connected with all other neurons to form a neural network.
