Freud introduces the term in the 1895 "Project" to refer to a set of permanently cathected (Psy) neurons which function to inhibit direct transmission of quantities of excitation along primitive pathways. They achieve this by providing a side channel through which energy is diverted. The actual acquisition and workings of such a system is difficult to picture precisely from Freud's description, but he clearly conceived its role as reducing the probability of painful associations, allowing inhibition of direct (reflexive) discharge of action, and permitting discrimination of memories (which are acompanied by activity of this ego system) from perceptions (which are not). Hallucinations present a potential confusion between perception and endogenously-produced images, and Freud calls the strongly-cathected "wishful" processes associated with hallucinatory images "psychical primary processes," while moderations of such pathways by activity of the ego-system he calls "psychical secondary processes" (SE 3, pp. 326-327). The general original orientation of the nervous system is toward rapid and direct discharge of cathexis, and this continues to be the case in the "primary process" parts of the system. With experience, however, increasingly large parts of the system become richly connected pathways for small quantities of "bound" cathexis which allows tension to be drained off without either discharge through motor action or accumulation of unpleasurable levels of cathexis.