Quelques-unes des notions utilisées par Freud, il y a déjà un siècle, font le socle de l’inconscient freudien aujourd’hui. Pourtant, certaines d’entre elles sont tombées en désuétude. Mais, par le biais des découvertes actuelles en neurosciences, ces concepts, parfois anciens et néanmoins fondamentaux dans la logique freudienne, peuvent être à nouveau questionnés. C’est le cas de la perception. Ce phénomène, étudié par Freud dès ses premières recherches, est, en neurosciences, un vecteur de recherches très dynamiques dans les études sur l’inconscient. Cette notion devient alors un support possible pour une mise en tension dialectique, entre psychanalyse et neurosciences, à propos de l’inconscient et de la subjectivité.

Actually, there are lot of questions for psychoanalysis and neurosciences. Even if sometimes these two theories seem to be distant, and even if some questions are too different to be worked in the same way, some of them can be discussed by these two approaches. It certainly does not make sense to try to find a consensus between psychoanalysis and neurosciences: it's a real risk because, in this case, they’ll probably lose their specificity. But, even if differences and oppositions exist, there are some similar questions, which are related to both fields of research. Some concepts used by Freud are evoked in neurosciences. And, even if they affirm their differences with the creator of the psychoanalysis, neuroscientists speak about him and underline that he found out a lot of concepts still useful today. To build the unconscious in psychoanalysis, Freud needed different concepts. Some have fallen into disuse but through current discoveries in neuroscience, these notions, which are sometimes old but still fundamental in Freudian logic, can again be questioned. This is the case of perception. This phenomenon studied by Freud from its first researches (since 1896), is, in neuroscience, a very important support of experiences: many researches aim to understand the operations in cerebral treatment of information. And the first filters are the perceptions. They are a vector of very dynamic researches about the unconscious or, more precisely, about what it should be named “cognitive unconscious”. But even if we have to establish the difference between Freudian unconscious and cognitive unconscious, the notion of perception really becomes a possible support for a dialectic exchange between psychoanalysis and neuroscience about the unconscious, but more specifically about subjectivity.