During more active breathwork, several things are happening at the same time. Your breathing pattern changes, CO₂ levels can temporarily decrease, your level of physiological arousal changes, and your attention becomes increasingly focused on your breath, body and internal experience. Add rhythmic music, repetition and closing your eyes, and the experience can become very immersive.
Think of your everyday thinking mind as having a lot of browser tabs open at once, including planning, analyzing, remembering, worrying and monitoring what is happening around you. During breathwork, some of those tabs may become quieter. As attention shifts away from everyday thinking and toward the body and internal experience, sensations, emotions, memories, imagery or insights may become more noticeable.
Some people describe reaching a state in which they feel deeply absorbed, lose track of time, experience vivid imagery or colours, feel unusually connected to themselves, or have an unexpected emotional release or insight. Occasionally, people describe these as breakthrough experiences because something that had previously felt difficult to access suddenly feels clearer or more available.
There is research exploring how intensive breathing practices may influence brain activity and networks involved in attention, self-reflection and our usual sense of self. Some breathwork practitioners believe that temporarily quieting the brain's usual analytical and self-monitoring processes, including activity associated with the prefrontal cortex and Default Mode Network, may help explain why people sometimes experience unusual clarity, emotional access or a different perspective during breathwork. These mechanisms are still being studied, and we cannot say that every person's brain is responding in this particular way.
For similar reasons, intensive breathwork is sometimes described as producing a psychedelic-like or non-ordinary state of consciousness without the use of a substance. That does not mean breathwork is equivalent to taking a psychedelic drug. Rather, it describes the fact that some people report changes in perception, emotion, imagery, sense of time or sense of self that can feel very different from their ordinary waking state.
Other people experience none of this. They may simply feel relaxed, physically energized, emotional, sleepy or more present. A dramatic experience is not the goal, and it is not evidence that the breathwork worked better. A quiet experience can be just as meaningful.