The Project for a Scientific Psychology (1895): a Freudian anticipation of LTP-memory connection theory.

Long-term potentiation (LTP) of synaptic transmission is considered a reliable cellular model of several forms of learning and memory. Described for the first time in 1973, this synaptic phenomenon consists in the enduring facilitation of the communication between two neurons in response to the sustained activation of the synapses by which they are interconnected. In a book of 1895 entitled Project for a Scientific Psychology, Sigmund Freud theorized about the possibility of representing memory at the synaptic level as "a permanent alteration following an event", and anticipated several crucial physiological properties of LTP. In the present article we aim at presenting Freudian theory on the functional organization of the nervous system developed in the Project, with particular respect to his ideas of the cellular bases of memory.