Do Magic Mushrooms Change Your Personality? The Science of Psilocybin and Openness

What science says about psilocybin, personality change, and the trait of openness (2026 Update)

Many people who have had a meaningful psilocybin experience describe feeling changed afterwards — more curious, more connected, more willing to look at life differently. For a long time, this was dismissed as subjective impression. Then researchers at Johns Hopkins University decided to measure it properly, and what they found was difficult to ignore. Psilocybin appears to change personality — specifically, it increases a core personality trait called openness — in a measurable, lasting way.

The Big Five Personality Traits

Before diving into the research, it helps to understand the framework scientists use to measure personality. The most widely validated model is the "Big Five" — also called the NEO model — which describes personality across five broad dimensions:

These traits are considered relatively stable in adulthood. Research generally shows that large personality changes in grown adults are rare, and when they occur — outside of major life events or long-term therapy — they typically happen very gradually over many years. This is what makes the psilocybin findings so interesting.

The Landmark Johns Hopkins Study

The most influential research on psilocybin and personality was published in 2011 by Katherine MacLean and colleagues at Johns Hopkins University. Participants in the study received a high dose of psilocybin in a carefully controlled, supportive environment. Researchers then measured personality using validated psychological tests at baseline, shortly after the session, and more than one year later.

The results, published in the Journal of Psychopharmacology, found significant increases in Openness following a high-dose psilocybin session. In participants who had a complete mystical experience during the session, Openness remained significantly higher than baseline more than one year after the experience. The increase in Openness was, notably, larger in magnitude than the personality changes typically observed in healthy adults over decades of life experience.

This is a remarkable finding. Personality researchers have long considered Openness one of the most stable adult traits. The idea that a single experience could produce lasting, measurable increases in this dimension challenges basic assumptions about how personality works.

What Does Increased Openness Actually Mean?

Openness to Experience is the personality trait most associated with creativity, aesthetic appreciation, curiosity, and a willingness to consider new perspectives. People high in Openness tend to be imaginative, intellectually curious, and more comfortable with ambiguity. They are more likely to seek out new experiences, appreciate art and music deeply, and approach problems in unconventional ways.

Concretely, people who report increased Openness after a psilocybin experience often describe:

These are not small shifts in how someone feels for a few days. In the Johns Hopkins study, these changes persisted for over a year in participants who had a full mystical experience — suggesting that something genuinely changed in how these people relate to themselves and the world around them.

Psilocybin Therapy and the Full Personality Picture

Subsequent research has expanded the picture beyond Openness alone. A 2018 study published in Acta Psychiatrica Scandinavica examined personality changes in patients with treatment-resistant depression who underwent psilocybin therapy. The findings showed:

This pattern — decreasing Neuroticism while increasing Extraversion and Openness — is exactly the direction most people would consciously want to move in. The authors noted that the increases in Extraversion and Openness may represent effects more specific to psilocybin therapy than to antidepressant treatment in general, since standard antidepressants tend to primarily affect Neuroticism and Extraversion but produce less dramatic changes in Openness.

The Mystical Experience as the Active Ingredient

One of the most consistent findings across psilocybin personality research is that the mystical experience matters. In the Johns Hopkins study, only participants who met criteria for a "complete mystical experience" showed the enduring increases in Openness. Those who had less complete experiences showed smaller or non-significant personality changes.

A mystical experience in this context typically involves a sense of unity with everything, transcendence of time and space, a profound sense of sacredness, and deeply felt positive emotion. It is not simply a pleasant trip. Researchers believe this type of experience may produce what they call a "psychological reset" — a temporary loosening of the rigid self-model that normally constrains how we perceive and relate to the world.

This is why set and setting are so important. The mindset and environment in which a person approaches a psilocybin experience significantly influence whether a mystical experience occurs and, therefore, whether lasting personal change follows. Our guide on how to prepare for a mushroom experience covers these foundations.

What About Microdosing and Personality?

Much of the personality research has focused on high-dose sessions in clinical settings. The relationship between microdosing and personality change is less well-established scientifically, though many microdosers report subtle shifts in mood, creativity, and emotional availability over time.

Current research on microdosing suggests it may support mood regulation, focus, and creativity — traits adjacent to Openness and Extraversion — but the full personality effect of regular low-dose use has not been as rigorously studied as single high-dose sessions. This remains an active area of investigation.

Important Context: Research Limitations

It is important to be honest about the limitations of this research. Most studies to date have been relatively small, and some have lacked control groups. The participants in early psilocybin studies were often pre-selected for positive attitudes toward psychedelics, which may not reflect how all people would respond.

Furthermore, personality change — even positive change — is not guaranteed. Experiences that are frightening or challenging do not necessarily produce the same effects as those characterised by positive mystical qualities. Set, setting, and the support of experienced facilitators all play significant roles.

The science of mushrooms and the mind is genuinely exciting, and it supports cautious optimism. However, psilocybin is not a magic solution, and the outcomes depend heavily on context and intention.