Self-modeling epistemic spaces and the contraction principle

Classic Psychedelic Drugs: Update on Biological Mechanisms

Renewed interest in the effects of psychedelics in the treatment of psychiatric disorders warrants a better understanding of the neurobiological mechanisms underlying the effects of these substances. During the past two decades, state-of-the-art studies of animals and humans have yielded new important insights into the molecular, cellular, and systems-level actions of psychedelic drugs. These efforts have revealed that psychedelics affect primarily serotonergic receptor subtypes located in cortico-thalamic and cortico-cortical feedback circuits of information processing. Psychedelic drugs modulate excitatory-inhibitory balance in these circuits and can participate in neuroplasticity within brain structures critical for the integration of information relevant to sensation, cognition, emotions, and the narrative of self. Neuroimaging studies showed that characteristic dimensions of the psychedelic experience obtained through subjective questionnaires as well as alterations in self-referential processing and emotion regulation obtained through neuropsychological tasks are associated with distinct changes in brain activity and connectivity patterns at multiple-system levels. These recent results suggest that changes in self-experience, emotional processing, and social cognition may contribute to the potential therapeutic effects of psychedelics.

The Minimal Phenomenal Experience questionnaire (MPE-92M): Towards a phenomenological profile of "pure awareness" experiences in meditators

OBJECTIVE

To develop a fine-grained phenomenological analysis of "pure awareness" experiences in meditators.

METHODS

An online survey in five language versions (German, English, French, Spanish, Italian) collected data from January to March 2020. A total of 92 questionnaire items on a visual analogue scale were submitted to exploratory and confirmatory factor analysis.

RESULTS

Out of 3627 submitted responses, 1403 were usable. Participants had a median age of 52 years (range: 17-88) and were evenly split between men and women (48.5% vs 50.0%). The majority of meditators practiced regularly (77.3%), were free of diagnosed mental disorders (92.4%) and did not regularly use any psychoactive substances (84.0%). Vipassana (43.9%) followed by Zen (34.9%) were the most frequently practiced meditation techniques. German (63.4%) and English (31.4%) were by far the most frequent questionnaire languages. A solution with 12 factors explaining 44% of the total variance was deemed optimal under joint conceptual and statistical considerations. The factors were named "Time, Effort and Desire," "Peace, Bliss and Silence," "Self-Knowledge, Autonomous Cognizance and Insight," "Wakeful Presence," "Pure Awareness in Dream and Sleep," "Luminosity," "Thoughts and Feelings," "Emptiness and Non-egoic Self-awareness," "Sensory Perception in Body and Space," "Touching World and Self," "Mental Agency," and "Witness Consciousness." This factor structure fit the data moderately well.

CONCLUSIONS

We have previously posited a phenomenological prototype for the experience of "pure awareness" as it occurs in the context of meditation practice. Here we offer a tentative 12-factor model to describe its phenomenal character in a fine-grained way. The current findings are in line with an earlier study extracting semantic constraints for a working definition of minimal phenomenal experience.

Consciousness and the attention schema: Why it has to be right

This article describes some aspects of the underlying logic of the attention schema theory (AST) of subjective consciousness. It is a theory that distinguishes between what the brain actually, physically has, what is represented by information models constructed in the brain, what higher cognition thinks based on access to those models and what speech machinery claims based on the information within higher cognition. It is a theory of how we claim to have an essentially magical, subjective mind, based on the impoverishment and reduction of information along that pathway. While the article can stand on its own as a brief account of some critical aspects of AST, it specifically addresses questions and concerns raised by a set of commentaries on a target article.