The brain’s white matter shows the many nerve pathways between different areas. White matter is made up of nerve fibres, called axons, which use electrical signals to carry information.
The blue-coloured nerve pathways connect the cerebrum, at the top of the brain, to the brainstem at the bottom. Those shown in green connect the front and back of the brain. And those coloured red are nerve connections between the brain’s left and right sides.
When you learn something, it is actually these synapses whose efficiency increases, thus facilitating the passage of nerve impulses along a particular circuit. For example, when you are exposed to a new word, you have to make new connections among certain neurons in your brain to deal with it: some neurons in your visual cortex to recognize the spelling, others in your auditory cortex to hear the pronunciation, and still others in the associative regions of the cortex to relate the word to your existing knowledge.
Picture Credit : Google