Sri Aurobindo
Letters of Sri Aurobindo
Volume I - Part 2
Exact images are retained by the subliminal memory. All that is subliminal is described by ordinary psychology as subconscient; but in our psychology that cannot be done, for the consciousness that holds them is as precise and far wider and fuller than our waking or surface consciousness, so how can it be called subconscient? Conscious memory is that which can bring up at 
any moment we like the memory of a thing, it is under our control. Subliminal memory can hold all things, even those which the mind cannot understand, e.g. if you hear somebody talking Hebrew, the subliminal memory can hold that and bring it up accurately in some abnormal state, e.g. the hypnotic. Subconscient memory is a memory of impressions; when they come up as in dream, either the result is something incoherent or fancifully rearranged or it is only the essence of the thing, its psychological deposit that comes up, e.g. sex, fear, some particular libido as the psychoanalysts call it, but the expression given to the latter need not be the same as memory would give; it may repeat the same forms if it gets hold of the mechanical mind in the physical to help its expression, but also it may be quite different from anything in real life.