After David Hartley's concept of memory in the "Doctrine of Association." 

David HartleyDavid Hartley (1705 – 28 August 1757) was an English philosopher and founder of the Associationist school of psychology. His work was part of the basis for Wordsworth's poetic method.

From his "Doctrine of Association":

The course of reminiscence and of the thoughts generally, when not immediately dependent upon external sensation, is accounted for by the idea that there are always vibrations in the brain on account of its heat and the pulsation of its arteries. The nature of these vibrations is determined by each man's past experience, and by the circumstances of the moment, which causes one or another tendency to prevail over the rest. Sensations which are often associated together become each associated with the ideas corresponding to the others; and the ideas corresponding to the associated sensations become associated together, sometimes so intimately that they form what appears to be a new simple idea, not without careful analysis resolvable into its component parts.