*Psychoanalysis and Psychedelic Psychotherapy – A New Modern Synthesis? DOI: http://dx.doi.org/10.5772/intechopen.109095*

that is qualitatively different than normal cognition [4]. This form of cognition corresponds to Freud's primary process of thinking, which is symbolic in nature and characteristic of an immature ego where representations take place by allusion or analogy, where memory or ideas may be used to stand for a whole, and *vice versa*. Several different thoughts may be represented by a single thought or image. Verbal representations here are less exclusive, and visual or sensual impressions may appear instead of a word, paragraph or entire chapter. A sense of linear time does not exist; past, present and future are one [5]. Primary process thinking is poetic and fluid and reveals sense impressions, symbol formation and early organizations of sensual and emotional experience. These building blocks create a unique creative vocabulary and poetic palette of representations for inner world formation and enrichment. Ideas about the self and the worldly surround are built on tapestries of fantasy, symbolic representation and belief that defy logic and reason and are instead linked by creative similarities typically encountered in childhood thinking and ideation [6]. It is these elements that provide the substrates of dreams and become the ingredients of the organizational structures and lenses through which we perceive and construct our sense of self and the world.

Recent neuroimaging studies propose theories of how and why the mechanisms of action of classical psychedelic medicines on the serotonin 2A receptor induce a heightened brain state for transformation. It has been speculated that up-regulation of this system, modulated through the binding on the receptor, might prime a "pivotal mental state" that is hyper-plastic for brain and mind states, and provide an enhanced rate of associative learning with the potential for enhanced psychological transformation [7]. Another speculation involves developmental *critical periods* that mark points of exquisite sensitivity to environmental inputs. Psychedelic medicines, it is suggested, may remove the brakes on adult neuroplasticity to catalyze a state in which critical neurodevelopmental windows are reopened [8].

All of these theories of brain activation capture the unique perceptual field that is accessed during a psychedelic session. Within these states, access to early life experience becomes available through symbolic representations and unique modes of knowing. The opening of these critical developmental windows can render a mind exquisitely sensitive to inputs from the treatment setting, permit a privileged set of conditions for exploration and discovery, and present novel perceptions and opportunities for impactful corrective experience. The psychotherapist, in turn, becomes available as a new object to be introjected for both enrichment and repair, but also as a *companion* to accompany and participate in the psychedelic experience, replete with early caregiver function provision.
