Hello, in this class, we are going to learn a little bit about our brain's biology. 1
We'll use this knowledge in future classes to further our understanding of learning processes. 2
Our brain is made up of more than a hundred billions of neurons. A typical neurons in the brain, looks 3
like this. 4
It has a nucleus that controls the entire neuron and a cell body that organizes and keeps the cell 5
functional. 6
It also has thousands of dendrites and Axon. 7
Neurons receive a signal through its thousands of dendrites and pass it to other neurons, through Axon. 8
The junction between dendrites is the Synapses. The synapses don't actually touch. The way 9
it works is that an electrical signal shoots down the axon, until it reaches the synapses where 10
neurotransmitters carries the messages in across the synaptic gap in chemical form and on the other 11
side, dendrites receive the neurotransmitter and it plugs into the receptor like a key into a 12
hole. 13
And this opens ion channels in the cell membrane to turn the signal back into electricity. 14
If the electric charge at the receiving neuron builds up beyond a certain threshold that nerve cells 15
fires signal along its own Axon and the entire process repeats. 80 percent of signaling is done 16
by two neurotransmitter that balances each other's effect. 17
Glutamate is tired of the activity to begin the signaling and Gamma Aminobutyric acid, short form 18
GABA clamps down on activity. 19
The more often the connection is activated, the stronger the attraction becomes, which is what neuroscientists mean by 20
"Neurons that fire together, wire together." 21
There are a second set of neurotransmitters that regulate the transmitting process and everything 22
the brain does. 23
These are serotonin, norepinephrine and dopamine. 24
They instruct neurons to make more glutamate, or they might make the neurons more efficient or alter 25
the sensitivity of its receptors. They commonly control mood, emotions, attention, perception, 26
motivation, arousal and plays an important part in learning. 27
Another class of molecules that influences learning are combinedly called factors. Most prominent of 28
which is Brain-drive neurotrophic factor BDNF. 29
These factors bind and maintain cell circuitry, the infrastructure itself. 30
BDNF improved the function of neurons, increases their growth and strengthen and protect them against 31
the natural process of cell death. 32
Commonly, these three classes of chemicals control the learning process, and if we can master them, 33
then we can master the whole process and that is the ultimate goal of our course. 34
Happy Learning!