Mushroom visuals refer to the distinct sensory perceptions induced by psilocybin, the primary psychoactive compound found in certain species of fungi. These experiences involve alterations in how a person perceives their surroundings and internal mental imagery. The phenomena are a direct result of psilocybin’s interaction with the brain’s complex neural networks. This article explores the neurobiological basis for these sensory changes, the various forms they can take, and the factors that influence their manifestation.
The Science Behind the Sights
When psilocybin is ingested, the body converts it into psilocin. Psilocin acts as a serotonin receptor agonist, mimicking the natural neurotransmitter serotonin. It exhibits its strongest binding affinity for the 5-HT2A receptors, which are abundant in the brain’s cortex.
This binding and activation of 5-HT2A receptors lead to increased excitability of pyramidal cells in cortical layer V, resulting in heightened glutamate release in the neocortex. This causes a decrease in brain blood flow and venous oxygenation, particularly in central brain hubs like the thalamus and the anterior and posterior cingulate cortex. This stimulation also alters the brain’s functional connectivity.
Psilocin decreases functional connectivity within the Default Mode Network (DMN), a set of interconnected brain regions active during self-referential thought and sensory filtering. Areas like the medial prefrontal cortex (mPFC) and posterior cingulate cortex (PCC) show reduced connectivity. Concurrently, global brain connectivity and connections between different brain networks increase. This disruption of the DMN’s normal filtering and communication pathways is the mechanism behind the visual and perceptual changes experienced during a psilocybin journey.
Types of Visual Experiences
The visual alterations experienced under psilocybin can range from subtle enhancements to immersive imagery. These experiences are categorized into two types: Open-Eye Visuals (OEVs) and Closed-Eye Visuals (CEVs). Both types stem from alterations in how the visual cortex processes information.
Open-Eye Visuals involve changes to existing visual stimuli when eyes are open. Surfaces, such as walls or floors, may appear to ripple or “breathe,” and objects can seem to melt or undulate. Colors often become more saturated and vibrant. Moving objects might leave behind faint trails or “tracers.” Geometric patterns, intricate and symmetrical, can also overlay or distort real-world textures and surfaces.
Closed-Eye Visuals, in contrast, manifest when the eyes are closed or in a completely dark environment. These visuals often begin as simple speckles, evolving into complex, detailed, and ever-moving patterns. Common CEVs include intricate geometric shapes, often resembling fractals, that shift and transform, and kaleidoscopic imagery with symmetrical, repeating patterns of vibrant colors. At higher intensities, these internal visions can develop into fully formed scenes, landscapes, or even narratives. The brain’s visual regions show increased self-inhibition and reduced synaptic gain during these CEVs, which amplifies internal signals in the absence of external sensory input.
Factors Influencing Visual Intensity
The nature and intensity of visual experiences with psilocybin are influenced by several variables. These factors include the dosage consumed, the individual’s mindset or “set,” and the surrounding environment or “setting.” Understanding these elements can help anticipate the character and strength of the visuals.
Dosage plays a direct role in determining the scope of the visual effects. Microdoses (0.1-0.3 grams of dried Psilocybe cubensis mushrooms) often do not produce noticeable visual alterations but may subtly enhance focus or mood. Low doses (0.5-1.5 grams) may result in mild visual effects, such as enhanced color perception or slight distortions, alongside increased sensory awareness. Moderate doses (2-3.5 grams) are more likely to induce pronounced visual and auditory hallucinations and altered perceptions of time. High doses (exceeding 3.5 grams) can lead to very strong, immersive visual landscapes and profound experiences.
An individual’s “set,” or their psychological state including mood, expectations, and emotional well-being, shapes the character of the visuals. A positive and relaxed mindset fosters more pleasant and flowing visual experiences. Conversely, feelings of anxiety, fear, or apprehension entering the experience can lead to more chaotic, unsettling, or challenging imagery. Previous experience with psilocybin has also been linked to more pleasant experiences.
The “setting,” or the external environment where the experience occurs, impacts the visual content and overall feel. Factors like lighting, music, and physical surroundings (e.g., nature versus a cluttered room) influence the imagery perceived. A calm, comfortable, and aesthetically pleasing environment, like a decorated room, contributes to a more positive and visually harmonious experience.
The Phenomenon of Synesthesia
Synesthesia is a perceptual phenomenon where the stimulation of one sensory or cognitive pathway triggers an experience in another sensory pathway. It involves a blending of senses typically processed separately. While some individuals are born with synesthesia, psilocybin can temporarily induce cross-sensory perceptions.
During a psilocybin experience, examples include “seeing” sounds as specific colors or shapes. Patterns may visually move in sync with music, or sound waves may be seen. Some report feeling textures when listening to music. Most drug-induced synesthesia instances are auditory-visual in nature. This phenomenon arises from psilocybin’s ability to create a “hyperconnected” brain state, where regions that usually do not communicate extensively become more interconnected, leading to cross-communication between sensory areas.