Is it possible to experience a state similar to a psychedelic experience without LSD, psilocybin, or any substances at all?
In 2026, neuroscientists from Argentina described a rare case of a woman who could voluntarily enter an unusual state of consciousness — with vivid geometric imagery, altered body perception, a weakened sense of self, and an experience of unity with the surrounding world.
The researchers conducted 20 functional MRI sessions with her and found that this state was accompanied by a stable and reproducible reorganization of brain activity.
The most interesting part was that with classic psychedelics like LSD or psilocybin, brain activity often becomes more variable: signal entropy increases, habitual networks interact less rigidly, and brain dynamics become less predictable.
Here, almost the opposite happened. When the participant entered the unusual state, the entropy of the BOLD signal decreased. At the same time, the statistical complexity of brain activity increased.
In other words, the brain became not more chaotic, but more structured — although the subjective experience became extraordinarily rich.
Simultaneously, the connectivity between large neural networks changed. Visual areas interacted more weakly with some sensory and motor systems, while certain networks of internal attention, salience, and self-reference rewired their connections.
The transition itself looked especially interesting. First, the neural organization temporarily became less stable, as if the brain left its usual mode of operation. Then a new relatively stable configuration emerged. It was something like a switch between two modes of consciousness.
This is important because altered states are usually difficult to study. Meditation, trance, deep mystical experiences, or psychedelic experiences vary greatly from person to person and are poorly reproducible on command. Here, the state could be induced voluntarily and repeated many times inside the scanner.
That is why the study provides a rare opportunity to observe not just an unusual experience, but the very process of the brain transitioning from one stable state to another.
At the same time, the practical significance of the work may be much broader than the unusual case itself. Such studies can help better understand how brain organization changes in patients with disorders of consciousness and why subjective experience can persist even with greatly altered neural network activity.
Another promising direction is non-pharmacological therapies for anxiety and depression. If it turns out that some altered states of consciousness can indeed be reliably induced without substances, then in the future the therapeutic effect might be separated from the pharmacological agent itself. Then not only the substance that triggers the state, but also the very configuration of conscious experience a person enters, would become important.
Many questions remain. Scientists need to link specific moments of subjective experience to neural network dynamics, understand why entropy decreased instead of the expected increase in this case, and find out how widespread the ability to voluntarily enter such states is among people.
The study is based on just one person. It does not prove that anyone can learn to enter such a state, nor does it mean that the experience is fully equivalent to the effects of psychedelics.
But it shows something important: the brain can create extremely unusual forms of subjective experience without external chemical influence — simply by changing its own network organization.
And one of the most intriguing ideas here is precisely that the richness of conscious experience does not necessarily require greater neural chaos. Consciousness can become more unusual precisely when the brain becomes more organized.
The work of Pablo Barttfeld, Gabriel Della Bella, and their colleagues does not provide a definitive answer to the question of the nature of altered states. But it opens another door into understanding how plastic the very architecture of human consciousness can be.
