Speculations on a Neural Substrate for Immediate Memory

We carry with us a fairly detailed memory of the immediate past. In the course of time, a huge bulk of information passes through this memory, but only a fraction remains available for long periods. It is generally accepted that the memory of the near past is carried by the electric activity of the cerebral nerve cells. This assumption is based mainly on two arguments: (a) It is hard to conceive of any mechanism whereby stored information could be continuously modified to encompass an endless spectrum of variations except by electrical activity. (b) Any major disturbance of the electrical activity of the brain (such as electro-shock, hypoglycemic shock or concussion) disrupts the memory of events preceding the disturbance.