# Critical Meditation Theory

[Terminology note: "samatha", "jhana", "insight", "stream entry", "homunculus" and "non-local time" are technical jargon defined in [Cyberbuddhist Jargon 1.0](https://www.lesswrong.com/posts/KuiDgXs7Qm9YBJpAv/rationalist-cyberbuddhist-jargon-1-0)]

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To understand how meditation affects the brain from an outside (neuroscientific) vantage point, it is necessary to understand criticality. **Criticality** comes from the mathematical study of dynamical systems. **Dynamical systems** are systems in which a point moves through space. Dynamical systems can be described on a continuum with ordered on one end and disordered on the other end.
- An **ordered** system has a small, positive number of stable attractors. Fluctuations die out quickly.
- A **disordered** system has chaotic, turbulent, or equivalent behavior.

On the threshold between ordered and disordered is the **critical point**. Systems more disordered than the critical point can be described as **supercritical**. Systems less disordered than the critical point can be described as **subcritical**. Systems at the critical point maximize **complexity**, which is a measure of entropy expressed across a variety of time scales.

With that mathematical terminology out of the way, let's get into the neuroscience.

EEG scans have shown that the human brain exhibits scale-free temporal statistics and behavior, which implies it is operating near criticality. The current theory is that resting-state brain networks hover around criticality. Focused attention tasks temporarily drive the brain more subcritical. Strong emotional states, creative tasks and psychedelics temporarily drive the brain more supercritical. Quiet alertness requires near-criticality.

Why do these different tasks rely on  different network dynamics? Well, if you want to pay stable attention to something then your brain's network activity needs to be stabilized, which means it should be in a relatively subcritical mode. If you want your brain to think in new ways then it should be open to many different possibilities, which means it should be in a relatively supercritical mode. And if you want to notice the finest sensory signals coming in, then your brain should be in a relatively critical mode because that's where small signals propagate best across time scales.

Note the "relatively" qualifiers. Remember when I said that the resting brain operates near criticality? To be more precise, it actually operates at **subcriticality**. The brain going too far in the supercritical direction can cause effects like seizures, psychosis, or psilocybin-associated behavior. These behaviors are…maladaptive (though vision quests can produce behavioral improvements as an aftereffect).

If you're a meditator, then the phrases "focused attention" and "quiet alertness" probably got your attention. That's because samatha (jhanic) meditation is all about focused attention and Zen (insight-ish) meditation is all about quiet alertness.

What happens when we look for connections between meditation and criticality-related measures? [Deep jhana reduces chaoticity and moves dynamics toward criticality.](https://arxiv.org/abs/2511.20990?utm_source=chatgpt.com)

The fact that meditation reduces chaoticity should be no surprise to anyone who has calmed their mind by sitting quietly and paying attention to the breath. The fact that insight meditation nudges the dynamics toward criticality should be unsurprising to anyone who has experienced stream entry. And the fact that insight meditation moves the brain in the direction of supercriticality should be no surprise to anyone who has experienced vipassana sickness, especially if you have experienced a meditation-related psychotic break.

What's really cool about the Criticality Theory of Meditation is that it provides a mathematical foundation for understanding how things like the homunculus and non-local time get dissolved by insight practice. These are just [attractors](https://slatestarcodex.com/2016/12/14/ssc-journal-club-mental-disorders-as-networks/). If your network activity moves toward supercriticality, then the attractors disappear. This is how psychedelics cause temporary ego death (by temporarily making your neural activity more chaotic) and how Zen causes permanent ego death (by [permanently moving your set point in the direction of supercriticality](https://www.ub.edu/brainvitge/wp-content/uploads/2019/07/Escrichs_FSN_2019.pdf)).