Natural Philosophy: Neuroscience and memory

In The Palaces Of Memory: How we Build the Worlds Inside Our Heads by George B. Johnson

This an excellent explanation of the development of neuroscience as it relates to memory in the human brain. The author does a good job of explaining the various concepts and mechanisms for the layman; you don't have to have a degree in Biology or Chemistry to understand the subject related here. A good introduction to the vast field of Cognitive Science in general. Recommended.

Further comments:

I have studied the area of applied physics concerning Electromagnetism as it relates to the design, installation, and maintenance of electrical systems and devices. In my studies (both formal and self-educated), I have surveyed electronics, computers, information theory, and cybernetics, among other things of related interest. The deeper I delve into the details of these subjects, the more I see the similarities between the underlying principles of man-made machines and biological machines. In my reading of the above referenced book, I noticed some striking parallels between the inner workings of solid state devices (SCRs, transistors, microprocessors, etc.) and the action of neurons in the process of an organism forming memories. I would have to quote too much about solid state physics to spell it all out, so I will just quote a small passage of the book and leave it to my audience to notice interesting correlations. From page 82:

Apparently, there was something special about NMDA receptors that was integral to memory--or at least to LTP. Researchers soon discovered that the receptor was unlike any other. Receptors generally work by opening ion channels in the cellular membrane. Until very recently, all ion channels were believed to be either chemically gated or electrically gated. Either the arrival of a neurotransmitter at the receptor or a change in membrane voltage caused them to open and close.

The NMDA receptor had the distinction of being both electrically gated and chemically gated--it required both kinds of stimulation before it would open its ion channel. Normally, a magnesium ion blocked the channel. No matter how much neurotransmitter crossed the synapse and stuck to a neuron's NMDA receptors, they would be incapable of responding. But if the neuron was already in a state of electrical arousal--stimulated by a previous signal that had activated the cell's normal glutamate receptors--then the magnesium stoppers would pop out. Now the NMDA receptors were free to react to a second rush of glutamate by opening their channels. The receptor was, in other words, a two-step device. One pulse cocked the trigger, the second pulse fire the gun. And while normal receptors worked by allowing sodium ions into the cell--the positive charges that led to the firing of an action potential--the NMDA receptor also let in calcium.

The importance of the last sentence of the second paragraph has to do with Dr. Gary Lynch's work on the mechanism of calpain in changing the cytoskeleton in the synapse. Fascinating stuff.