Basic Function of Neurons

The Thalamus
The thalamus is the way-station of the brain's networks. It has three circuits running through its walnut sized core. One circuit (Specific Nuclei) constantly scans the cerebral cortex looking for neurons that are active (something like a radar screen in the control tower of an airport). When it finds a cluster of neurons vibrating at 40 cycles per second it notes this and reports back to the thalamus headquarters. The mind creates a "map" of all such neural groups and goes to the reference circuit to make a comparison with stored repertoires of known things. The second or reference circuit (Reticular Formation) makes intelligent guesses about what is being seen, or heard, or felt as assembled by the cortical map. It uses a process of comparison and then selection of the best answer, and on rare occasion when it finds no answer it tells the mind it is mistaken that nothing is being seen or heard or felt. The third circuit in the thalamus (Intralaminar) is constantly searching memory to see what associations might be made with what is being recorded on the mapping circuit. Thus, if we are seeing the Eiffel tower (or a picture of it), the third circuit will likely pick up pieces of memory about Paris, or France, or towers in general.

Produced by:
John P. Eberhard, FAIA
e-mail: JPEber@aol.com