What happens in your brain during a breathwork session
People often describe a good breathwork session as feeling like their mind finally went quiet, or the opposite, unexpectedly vivid and open. Neither is imagination. EEG research on rhythmic breathing shows real, measurable shifts in brain activity. Here's what's actually been observed, in plain terms, and where the evidence stops.
Your brain produces electrical activity at different speeds, or frequencies, and each range is loosely associated with a state of mind. Fast beta waves dominate when you're alert, busy, or anxious. Slower alpha waves show up when you're relaxed but awake. Slower still, theta waves appear in deep relaxation, meditation, and the drowsy state just before sleep.
A 2018 review in Frontiers in Human Neuroscience (Zaccaro et al.) looked across multiple EEG studies on slow breathing, around six breaths a minute, and found a consistent pattern: alpha and theta activity increased, while beta activity dropped. That shift is linked to parasympathetic activation and better emotional control, and participants in the underlying studies reported lower anxiety after practicing. Separate research on yogic breathing (Brown & Gerbarg, 2005, Evidence-Based Complementary and Alternative Medicine) found a similar move toward alpha and theta dominance, similar to what's seen in meditation, with EEG readings pointing to vagus nerve stimulation as the likely driver.
This is part of why a session doesn't stay at one speed. Earth and Water, the slower opening rounds, give the nervous system the conditions this research describes, longer exhale, lower beta, more alpha and theta. Air and Fire pick up the pace and intensity, which is a different physiological event entirely, more stimulating in the moment, followed by a held breath and release. The come-down after that release is often where people report the clearest, most settled state of the whole session.
Most of these EEG studies are small, typically ten to fifty participants, and they measure minutes to hours, not months. They show that rhythmic breathing reliably shifts brainwave activity toward relaxation, they don't prove a specific long-term outcome for any one person. What people sometimes describe as visions, euphoria, or a felt sense of breakthrough during more intense rounds is a real and widely reported experience, but the deeper neurochemistry behind it is still an open question in the research, not something we'll overstate here.
This is educational information, not medical advice. Breathwork is not a substitute for treatment, see the FAQ for who should check with a doctor first.