A very important step forward has recently been taken in psychoanalysis by making a distinction between what remains unconscious because of the nature of the supporting memory system and those processes that have been made unconscious because of active repression. Significant progress can still be made following this line of investigation. However, most of the convenors at the New York conference on the unconscious have been interested in the neurological mechanisms underlying repression. Elucidating these mechanisms may encounter some difficulties, depending on which aspect is investigated of what may be a multifaceted, complex function. Recent findings in neuroscience reveal that the function of suppressing information is performed—even before learning itself—by a mainly subcortical circuit. The psychoanalytic mechanism of repression, however, insofar as it implies a change of meaning, must have cortical components whose neurological and cognitive aspects may be hard to investigate.