- Earlier I mentioned
that neural networks were inspired by the brain,
so it makes sense to take a quick view
at the ultimate computer.
There are many things we know about the brain
and so many other things we don't.
Here are some important things we do know.
The brain is made of neurons.
The brain is a biological neural network.
Each neuron in the brain
performs a very modest cognitive function
contributing to larger cognitive functions.
Finally, the combination of these
cognitive functions
results in our brain's mental ability.
Everything the brain does
is the result of these tiny computations,
feelings, memories, movement,
speech, dreams, all of it.
So let's take some of the known facts of neurons
to come up with a computational model
of a biological neuron.
The structure of biological neurons
consists of several parts.
We are only interested in three parts of the neuron.
Dendrites take electrical signals
coming from nerves or other neurons.
These signals may come from sense organs
like the eyes, tongue, or ears.
The nucleus of the neuron
is where some processing is believed to happen,
so that the combination of inputs
can yield some response.
This response is usually interpreted as binary,
so that if the stimulus
from the inputs is high enough,
it is said that the neuron
fires an output signal.
This output signal
goes through an extension called "The Axon"
into other neurons,
or some other part of the body
that will react to this signal, such as muscles.
Now let's build a computational
model of a neuron based on these three elements.