DMT is teaching scientists about consciousness and the human 'sense of self'

A fast-acting psychedelic is helping scientists probe how the brain builds the feeling of being a distinct self. In a controlled study with 27 healthy adults, researchers used DMT and watched brain activity change as their usual “sense of self” slipped away.

Dimethyltryptamine (DMT) is a psychedelic compound that briefly scrambles perception and self awareness.

Scientists usually shorten its name to DMT, and in this experiment the stronger trips matched stronger disruptions of self.

DMT and the sense of self

The work was led by Christopher Timmermann, a neuroscientist at University College London (UCL) who studies how psychedelics affect consciousness. 

His research group collaborates with partners in the Netherlands and the United States to map brain activity during intense altered states.

Volunteers visited the lab on two separate days, receiving a DMT infusion on one visit and an inactive placebo on the other. 

Researchers recorded electrical activity from the scalp throughout each session and later compared those patterns with the intensity ratings that people gave their experiences.

Because DMT acts within seconds and fades within about twenty minutes, it lets scientists capture a full “trip” inside a single recording window. 

That combination of speed and intensity has turned this substance into a useful probe of how the human brain constructs the “conscious” experience.

How brain signals shift

The team focused on alpha waves – repeating electrical bursts that are strongest during quiet wakefulness – because this rhythm is tied to self-related thought. 

Past studies have shown that when this pattern weakens, people often report feeling less anchored in their usual mental chatter.

Their analysis also centered on criticality, which is the precarious spot where brain activity sits between rigid order and runaway chaos. 

“Criticality refers to a brain state balanced between chaos and order,” Timmermann said while explaining how criticality supports stable self awareness.

Evidence from animals, patients, and simulations suggests that conscious brains hover near this point, helping them move information efficiently.

In the new experiment, DMT pushed alpha wave activity away from that critical point and into a quieter subcritical state. Here, patterns become harder to sustain across time, and the overall electrical signal looks less structured.

Participants rated how strongly their sense of self seemed to dissolve during the DMT session. Psychologists sometimes call this experience “ego dissolution,” because boundaries between self and world, or between past and future, feel far less solid.

The bigger that change was, the more intensely people reported ego dissolution on those scales.

DMT and changing brain signals

To describe this shift more precisely, the researchers tracked signal entropy – a measure of how unpredictable a signal is from moment to moment. 

Under DMT, the alpha band became more unpredictable yet less complex, suggesting that information was being carried in a more fragmented way.

To capture changes across time scales, the team used detrended fluctuation analysis – a method that summarizes how brain rhythms vary over longer stretches. 

This approach has been widely used to study healthy and disordered brain activity, linking long range temporal structure to cognitive performance.

Earlier DMT studies using detailed scalp recordings found reductions in alpha and beta power, plus increases in spontaneous signal diversity at peak intensity.

Those results match the idea that psychedelics nudge the brain into states with higher entropy and more fluid patterns of activity.

A later experiment that combined brainwave recordings with brain imaging found that DMT boosts connectivity across the cortex and weakens network boundaries. 

Those changes tracked the intensity of the altered state, hinting that widespread reorganization of communication goes hand in hand with strong psychedelic experiences.

How self breaks down

Many volunteers described the DMT state as one where the usual story of who they are over time stops holding together. 

When long range temporal structure in alpha rhythms weakens, the brain struggles more to link past, present, and future into one story.

“We rely on past narratives and future predictions to have a coherent sense of self,” explained Marco Aqil. Now at the University of Miami, Aqil highlighted this point when describing how DMT seemed to strip away that time-extended storyline of “self.”

In that sense, the altered brain state lines up neatly with reports of losing the usual narrative of being a continuous self.

DMT states and self-awareness

Work in animals and human patients suggests that when brains move too far from criticality, communication between deep structures and cortex becomes less flexible. 

One recent study found that low frequency rhythms near this edge of chaos support information flow between thalamus and cortex during waking states.

Analyses of resting brain activity in healthy people show that long range temporal correlations weaken in depression, schizophrenia, and some dementias. 

Work using detrended fluctuation analysis ties changes in signal structure to shifts in cognition, highlighting how stability and flexibility need to coexist.

Seen from this broader perspective, the DMT work adds another point on a curve linking criticality, information flow, and stable conscious experience. 

Learning how far the brain can move along that curve, and still support self-awareness, may help explain a range of altered states.

Because psychedelics promote plasticity in neural circuits, understanding their impact on criticality could eventually inform tightly supervised therapies, though that work is still early. 

For now, these studies mainly serve as controlled experiments that use altered states to reveal how everyday consciousness depends on finely-balanced network dynamics.

Lessons of “self” from DMT

This DMT criticality study relied on a modest group under strict screening, so its conclusions apply to that setting rather than casual use. 

Researchers also emphasize that psychedelic substances carry real psychological and physical risks, which is why studies like this happen in monitored medical environments.

Future work will test whether similar criticality shifts appear in meditation, anesthesia, sleep, or other states that unsettle the sense of self. 

If patterns hold, neuroscientists may use these changes in brain dynamics as a common language for comparing diverse routes into altered consciousness.

The study is published in the Journal of Neuroscience.

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