Mushrooms

What it feels like

The trip as it unfolds, what it does to seeing and to feeling, and the two directions it can go.

Over the hours

• The first hour, Coming up: Psilocybin becomes psilocin in the body and levels climb.
• About 2 hours, The peak: Psilocin is at its highest, and so are the effects.
• 5–6 hours, Coming back: The effects fade over five and a half to six and a half hours on average — longer at higher doses.

What you see, as the dose rises

• Threshold, Richer: Colour a little more saturated, light a little brighter.
• Light, Alive: Textures sharpen and begin to move; bright lights glow.
• Moderate, Breathing: Surfaces undulate, edges pulse and pattern grows out of texture; moving lights leave trails of separate afterimages.
• Strong, Geometry: Geometric pattern spreads over anything textured, and music can shape it; sizes and shapes shift.
• Very strong, Latticework: Brightly coloured, flowing latticework fills the whole field of view.

What it can feel like

• Big feelings: Emotions arrive strong and fast; everything feels more dreamlike as the dose rises.
• Time: Minutes stretch; past a few seconds, judging time falls apart.
• Self: At higher doses, "all notion of self and identity dissolved away" — and a sense of being one with everything.
• Awe: A mystical-type experience: unity, a sense of the sacred, of touching something true, beyond time and space, beyond words.
• Meaning: Fourteen months after one supervised session, 58% of volunteers ranked it among the five most meaningful experiences of their lives.

It can also go the other way. People's accounts of their worst trips fall into fear, grief, thoughts of death, fear of going insane, isolation, physical distress and paranoia — often with the dread that it will never end. Yet of nearly 2,000 people describing their most difficult trip, 84% said they'd benefited from it.

What tips it? Going in open, accepting and surrendered predicted good and mystical-type experiences; going in preoccupied, apprehensive or confused predicted hard ones.

What's happening in the brain

One receptor, a visual cortex making its own patterns, and a self network coming apart. The model lights each one as you read.

One lock

Psilocin switches on the serotonin 5-HT2A receptor, packed onto large neurons across the cortex. Block it with another drug and the psychedelic effects vanish.

The patterns

Psilocybin suppresses the visual cortex's alpha rhythm, and the more it does, the stronger the visions. The geometry people see — lattices, cobwebs, tunnels, spirals — is the shape of the visual cortex itself: excite that sheet of neurons and it settles into stripes and hexagons, which, seen back through the way the eye maps onto it, are exactly those forms.

The self dissolving

Psilocybin quietened hubs like the thalamus and the cingulate, and the drop in medial prefrontal activity predicted how intense it felt. It blurs the boundaries between the brain's networks, most of all in the default mode network, which holds together your sense of self — and the change tracks the experience.

Fear, quietened

It lowered the amygdala's response to negative images, and the drop tracked a rise in good mood. Part of the warmth of a good trip may be the alarm going quiet.

Time

Intervals of seconds to minutes are timed by circuits in the basal ganglia and cerebellum. On psilocybin, reproducing intervals longer than about three seconds, or tapping along to a slow beat, falls apart.

Questions people ask

The things people wonder about tripping — answered.

Risks and staying safe

Low on physical risk; the risks are mostly in the mind and in what you do.

Physically, psilocybin is among the least toxic drugs — about a thousand times a typical dose would be needed to kill, against about ten for alcohol — and it doesn't typically lead to addiction. In a survey of 135,095 adults, psychedelic use wasn't linked to more mental health problems.

The real risks

• A hard trip: The most likely problem. In one survey, 11% had put themselves or others at risk during their worst one.
• Psychosis: It can worsen mental illness in people who have, or are predisposed to, psychotic disorders.
• Lithium: In reports of psychedelics taken on lithium, nearly half described seizures.
• The wrong mushroom: Misidentified wild mushrooms cause most mushroom deaths.
• Lasting visuals: Uncommon, but visual disturbances can persist for months after.

Set and setting

• Go in calm and open, with a clear intention.
• A safe, familiar place, with someone sober you trust.
• Skip it with a personal or family history of psychosis, or on lithium.
• If it gets hard: it ends within hours, and letting go goes better than fighting it.

Check what you know

Five questions about what a trip is doing.

• People tripping on mushrooms, LSD, during migraines and even when pressing on their eyes describe the same few shapes: lattices, cobwebs, tunnels, spirals. Why the same shapes? They're patterns the visual cortex makes itself when it's over-excited, distorted by how the eye maps onto it. An excited sheet of visual cortex settles into stripes and hexagons, which, through the eye-to-cortex map, look like these exact forms.
• At the peak of a strong trip, someone says "I wasn't me any more — I was everything." What's happening in the brain? The default mode network, tied to the sense of self, is losing its boundaries. Psilocybin disrupted network boundaries most in the default mode network, tracking the experience, and ego dissolution rises with dose.
• A researcher gives volunteers a drug that blocks the 5-HT2A receptor, then psilocybin. What happens? The trip mostly doesn't happen. Blocking 5-HT2A with ketanserin blocked psilocybin's effects, dose-dependently.
• Two friends take the same dose. One goes in relaxed and curious; the other is stressed about work and worried about the trip. What does research predict? The relaxed, open one is more likely to have a good trip; the preoccupied one a harder one. Surrender and openness predicted positive, mystical-type experiences; preoccupation and apprehension predicted adverse ones.
• During a trip, a song seems to go on for an hour. Why? Psilocybin disrupts the circuits that time intervals longer than a few seconds. Timing of seconds to minutes runs through basal ganglia and cerebellar circuits, and psilocybin impaired reproducing intervals over about three seconds.