Letter to the editor regarding “Understanding subjective experience in psychedelic-assisted psychotherapy: The need for phenomenology”

To the Editor

I am writing to offer a critique of the recent opinion paper on the need for phenomenology in psychedelic-assisted psychotherapy (PAP) and to propose the inclusion of neurophenomenology (Varela, 1996) or non-reductive neurophilosophy (NRNP; Northoff, 2022) as essential frameworks for a more comprehensive understanding of how different structures of consciousness alter during the distinct phases of PAP.

The opinion paper eloquently argues for the significance of phenomenology in exploring subjective experience within PAP, asserting that this is not well accounted for by psychometric scales. In particular, it discusses that the creation of phenomenological profiles of how the structures of consciousness are altered during PAP could enrich our understanding of the experiential alterations that occur under the effects of psychedelics. Being in accordance with the points highlighted in the paper, I nonetheless believe that the inclusion of a broader perspective that incorporates neuroscientific investigations would largely benefit PAP. Indeed, phenomenology alone remains blind to the third-person perspective of empirical research, which is currently quickly growing with respect to psychedelics and PAP (Kwan et al., 2022), enlarging the comprehension of our first-person subjective experience under psychedelics. Therefore, I propose the employment of neurophenomenology or NRNP, since the integration of the phenomenal structure of experience into the characterization of neural dynamics these approaches promote may lead to an enhanced comprehension of the complex interplay between mind and brain underlying the therapeutic process and outcome in PAP.

In recent years, neuroscience has played a crucial role in uncovering the neural mechanisms underlying the effects of psychedelics and characterizing distinct neural signatures linked to different substances and dosages (for a review, see Kwan et al., 2022). Phenomenology complements this understanding by delving into the nuances of subjective experience. Integrating these two disciplines is thus crucial to bridging the gap between objective brain activity and subjective personal narratives. This is particularly true in the case of psychedelics, as they induce a shift in the way a specific content of consciousness is usually experienced, which may be accompanied by a shift in experiential structure and its neural counterpart. This in turn may give researchers and clinicians the possibility of creating more precise and complete profiles of how psychedelics change the basic structures of consciousness in the context of PAP, which can ultimately better inform PAP protocols.

Both neurophenomenology and NRNP postulate a bidirectional interaction between neuroscience and philosophy. The neurophenomenological approach (Varela, 1996) presents a methodological strategy in which first-person phenomenological reports and neuroscientific findings inform each other in a circular way in order to reach a more nuanced comprehension of the phenomenon of study.

On the contrary, NRNP (Northoff, 2022), starting from the idea that the borders between the distinctive scientific disciplines are ultimately byproducts of the human mind, allows for method and domain pluralism. With the notion of ‘common currency’ (Northoff, 2022), it suggests that time and space, that is, topography and dynamic, may be shared by both brain and mind. Unlike in neurophenomenology where there is no direct connection between brain and experience, NRNP thus provides a direct and intrinsic connection between brain and mind through time-space as manifest in neural and mental topography and dynamics (Northoff, 2022).

How can we achieve such a direct connection among disciplines as diverse as neuroscience, psychology, and phenomenology? Remarkably, NRNP provides a connection between the different domains, through the employment of ‘concept-fact iterativity’. This methodological strategy, conceiving the same content in distinct domains and/or methods, goes indeed beyond the mere parallel use of both logical-conceptual and observational-experimental methods and allows to search for similarities and differences with respect to the same content.

I argue that a deeper understanding of the direct connection of neural and mental levels indexing the temporo-spatial structure of consciousness as promoted in particular by NRNP can inform PAP interventions and contribute to the optimization of treatment protocols better than phenomenology alone. I maintain that this is the case as neurophenomenology and especially NRNP allow going deeper into the investigation of the mental and neural dynamics underlying the shift in the experiential structure fostered by psychedelics. This can inform about the neurophenomenological correlates of phenomena (e.g. ego dissolution and mystical experiences) that are emerging as key for positive therapeutic process and outcome.

In conclusion, while the opinion paper rightly highlights the significance of phenomenology in PAP, I argue that its extension to the brain as in neurophenomenology and especially in NRNP is essential for a more comprehensive understanding of PAP process and outcome. By integrating neuroscience and phenomenology within the proposed frameworks, we can bridge the gap between objective brain activity and subjective experiences: we can show their intrinsic topographic and dynamic connection which, in turn, can lead to improved therapeutic outcomes and ultimately advance our understanding of both mind and brain.