How Memory Is Stored
When you look up a phone number, the digits are coded as patterns of nerve impulses flowing around in a group of neurons. As long as the encoded numbers are “on-line” like this, your memory has access to the numbers. But what if you start thinking about something else before you dial? Those neurons now have been recruited for another purpose and no longer carry the original number encoding. So you have to look up the number again. But if the on-line activity goes on long enough, your memory of the number encoding can become stored permanently. How does that happen? Evidence indicates that new learning, as it becomes stored permanently causes new junctions (synapses) to be formed in the neurons of the circuit that originally encoded the information. You can even see physical signs in the form of new growths, called spines, on the nerve fiber terminals. But what creates these new spines and their functional connections? This involves new RNA and protein synthesis. This in turn requires s...