Primary and Secondary Process Mentation: Two Modes of Acting and Thinking from Freud to Modern Neurosciences

The purpose of this study is to return to Freud’s original descriptions of the primary and secondary processes in the light of modern neurosciences. In his Project for a Scientific Psychology, Freud draws the axes of the architecture of a mental apparatus: on a horizontal plane, the primary process transfers the excitation by impinging stimuli over a sequence of analogous states towards their discharge; thus, the primary process is essentially characterized by its associative tendency. On a vertical plane, the secondary process opposes the primary bottom-up pressure by a top-down inhibition with its origins in the purposive idea: the secondary process is essentially characterized by its inhibitory interventions. Freud later proposed that the primary and secondary process are seeking for perceptual, respectively thought identity. These different elements are coherent with the dynamics of the ventral and dorsal brain pathways respectively. Moreover, the dorsal pathway has an inhibitory influence upon the ventral pathway, much like the secondary has upon the primary. This influence is exerted thanks to what Freud called the “indications of reality.” We propose to equate these indications with the efference copies in modern neurosciences since they proceed from the same physiology and have the same function, besides originating from the same Helmholtzian source. Finally, even if both primary and secondary processes serve the death drive through the pleasure and the reality principle respectively, only the secondary process, requiring the bearing of an accumulation of excitations, also serves the life drive.