Psychological Explorations of the Magic Mushroom (Psilocybin) Experience, Part I : Subjective Effects and Time Passage Perception, José Arturo Costa Escobar & Antonio Roazzi, 2011

Psychological Explorations of the Magic Mushroom (Psilocybin) Experience, Part I : Subjective Effects and Time Passage Perception

José Arturo Costa Escobar, M.S., Antonio Roazzi, Ph.D.

Neurobiologia, 2011, 74, (3-4), 81-97.



Magic mushrooms are rich in the active compound psilocybin, whose activity on consciousness deeply alters cognitive functions, can promote spiritual/mystical experiences and has high biomedical and psychotherapeutic importance. Twenty-eight participants underwent a magic mushroom experience after consuming dehydrated Psilocybe cubensis mushrooms at the dosage of 55.6 mg/Kg (350 μg/kg of psilocybin). Results of subjective aspects of the experience through the Hallucinogen Rating Scale revealed equivalent dosage effects comparable to other studies and similar to those of the psychedelic beverage Ayahuasca. The effects on subjective perception of time duration verifi ed an underestimation of the velocity of temporal passage by participants after substance intake, in which subjects presented longer subjective durations of seconds. Results are discussed in the context of literature produced in the psychopharmacological and cognitive fields.

KEY WORDS : Time experience; Hallucinogens; Psychedelics; Psychotomimetics; Cognition.


Magic mushrooms of the genus Psilocybe are psychoactive fungi found in some places in the world (1), including Brazil (2, 3). Human consumption of magic mushrooms stretches back to pre-history and has traditionally accompanied magic rituals in American cultures (4-9). The role of the consumption of these and other substances with psychoactive activity on the evolution of the human mind could have been relevant (10, 11).

Psilocybe mushrooms have the active compounds psilocybin and psilocin, which act as agonists to
serotonin receptors (5-HT, 5-hydroxytryptamine), causing modifi cations in sensorial perception, mood,
emotion, memory and cognitive processes (12). Contemporary use/abuse of these mushrooms occurs mainly in a recreational mode, but epidemiological studies in Brazil could not register an important occurrence of abuse (13-16).

The complexity of effects on consciousness caused by psilocybin and analogous substances (e.g. DMT, LSD, mescaline) was better expressed in the past by use of the term psychedelic (mind-altering). Others terms like hallucinogenic (causing perceptions without a real base), psychotomimetic (psychosis mimesis) and entheogen (“God within”) are also used in the literature (12, 17, 18).

Recently, it still has been necessary to defi ne what a psychedelic experience could be (19, 20). Due to the unique peculiarity of these substances on mental processes, they are becoming important tools to investigate biological correlations of altered states of consciousness, exploration of psyche and also as facilitators of psychotherapy (12, 21-26).

The ability of psilocybin to diminish the capacity of subjects to use contextual information has been seeing as an indicator of an increase in creativity. In short, it could be explained as an amplifi cation of consciousness that permits subject to realize unusual semantic relationships of information or content. In this way, subjective experience refl ects an increase in creativity with parallel decrease of performance in objective measures under the state of altered consciousness, making remote mental associations more accessible (27, 28). The increase in intrusive information from internal and external orders to cortical areas, by this amplifi cation of consciousness, can be interpreted as an amplifi cation or increase of
conscious information processing (24, 25).

Alterations of psilocybin action on subjective perception of time were observed. Studies found difficulties/defi ciencies of the subjects in accurately determining intervals of time. The alterations found indicate an incapacity to keep synchronization or correctly reproduce intervals of time, showing a tendency toward slower subjective time ratings (29, 30).

PET studies (Positron Emission Tomography) have demonstrated that psilocybin, by serotonergic action, promotes hyper-frontality, i.e., an increase of neuronal activation in the prefrontal cortex and the brain as a whole (25, 31, 32). It is believed that a primary or secondary imbalance of neurotransmission by psychedelics affects the mechanism responsible for information processing and “fi ltering” of sensorial information, causing increased information intrusion to the system and consequent hyper-activation of the prefrontal cortex (24, 25, 32, 33).

Research done on psilocybin focused on visual processes has shown its ability to induce illusions of global motion of static objects or of textured surfaces. This is explained as due to the regulation of visual
process by serotonin receptors in visual areas of the brain, on which psilocybin acts (34). The infl uence of serotonin receptors on attention mechanisms concerned with binocular rivalry have been demonstrated, whose substantial action results in a decrease of interruption rates and increase of transition and confusion of perceptual experience (35). Significant results on perceptual rivalry on Tibetan monks after meditation were similar to those found for psilocybin (36), suggesting a qualitative similarity of functioning between psychedelic states and meditative/mystical states, as suggested by some researchers (37-46).

Some fMRI (functional magnetic resonance imaging) studies point to the importance of physiological regulation of serotonin receptors 5-HT1A/2A on attention brain processes by frontal cortex activity (47). Carter et al. (2005) have shown the action of psilocybin on reducing attention on the ability of object tracking, that suggests an independence between attention and working memory, normally attributed to be functionally dependent mechanisms, or that co-dependence of these mechanisms is more limiting than suggested by the current literature (48).

Studies with psychedelics seem to present a common root with psychopathologies. This idea has existed in science since the early studies with these substances began a century ago (49). Contemporary studies are still investigating the relationships of psychedelic and schizophrenic conscious states (12, 24, 25, 31, 50).

Psychopharmacology studies with psilocybin and analogous substances are one of several research spheres of human cognition. All of which contribute to elucidating mental/neuronal functioning in uncommon states of consciousness like psychopathology, religious experience, mind/self transformations and psychotherapy (21, 51). Therefore, investigations with psilocybin have been developed in scientific fields concerned with perception, neuroimaging, neurotheology, language, psychology and psychotherapy. Such research constitutes an important tool for understanding brain functioning under psychedelic states as well as psychological processes in general. Our study is the fi rst exploratory study developed in Brazil with Psilocybe mushrooms on humans, according to our literature review. Here, we present some subjective results exploring viability of developing psychological investigations of a special state of consciousness promoted by magic mushroom consumption and their impacts for our understanding of human mind functioning.