Meditation Defined
Series: Neural Performance Series | December 2025Meditation is deliberate mental training that, when practiced consistently, leads to measurable structural changes in the brain—specifically in the Default Mode Network (DMN), prefrontal cortex, and amygdala. It is the practice of doing one thing while noticing when you're doing something else, and redirecting.
The Brain's "Screensaver" Problem
Your brain has a mode it slips into when you're not actively focused. Scientists call it the Default Mode Network (DMN)—a set of brain regions that light up during mind-wandering, self-referential thinking, and rumination.
This is the mental chatter that says: "I should have said that differently," "What if this goes wrong," "I wonder what they think of me." The DMN isn't inherently bad—it's involved in autobiographical memory and social cognition—but for many people, it's a runaway train. An overactive DMN is correlated with depression, anxiety, and chronic rumination.
What does meditation do to the brain?
Judson Brewer, a psychiatrist and neuroscientist at Brown University, used real-time brain imaging to show that experienced meditators have significantly reduced activity in the Posterior Cingulate Cortex (PCC)—a hub of the DMN. The PCC is where "I, me, mine" thinking lives. When it quiets, so does the mental noise.
What's more interesting: Gamma wave activity, typically associated with "flow states" and high-level cognitive processing, increases during meditation. Gamma waves are the fastest brainwave frequency and are correlated with peak mental performance, insight, and information synthesis.
Neuroscientist Richard Davidson at the University of Wisconsin found that long-term meditators have 25x more gamma activity than non-meditators, even at rest. Their brains were rewired—not just during practice, but as a new baseline.
Which meditation techniques work?
There is no "best" meditation. The right one depends on your goals. Here are the main traditions, stripped of branding:
Focus on generating feelings of warmth and goodwill toward yourself and others. Research shows it activates the insula and anterior cingulate cortex, increasing empathy and emotional regulation.
Observe sensations without reaction. The goal is to see the impermanent nature of all experience. This builds equanimity—the ability to witness discomfort without catastrophizing.
No focus on breath or mantra—just sit with open awareness. It is considered the most "advanced" practice because there's nothing to hold onto. Ruthless in its simplicity.
The best technique is the one you'll actually do. If you're starting out, begin with mindfulness or simple breath awareness. The key is consistency—daily practice for 10-20 minutes changes structure faster than occasional long sessions.
Why the Breath Matters
Most meditation techniques return to the breath for a reason. It's always available, it's neutral, and—crucially—it bridges the voluntary and autonomic nervous systems. When you focus on breathing, you're indirectly influencing your heart rate variability, stress hormones, and nervous system state.
For a deeper dive into the neuroscience of breath, see our Breathwork Guide.
Key Relationships (Semantic Triplets)
| Entity (A) | Relationship | Outcome (B) |
|---|---|---|
| Meditation | Decreases | DMN Activity |
| Meditation | Increases | Gamma Waves |
| PCC Quieting | Reduces | Self-Referential Rumination |
| Metta Practice | Activates | Insula (Empathy) |
The Yoga Connection: Dhyana
In the yoga tradition, meditation is called Dhyana—the seventh limb of Patanjali's eight-limbed path. It follows Dharana (concentration) and precedes Samadhi (absorption). The progression is logical: you must first be able to hold attention before attention can dissolve into its object.
Modern meditation is often taught in isolation, but in classical yoga, it's the culmination of physical postures (asana), breath control (pranayama), and sense withdrawal (pratyahara). The body is prepared so the mind can sit.
Ready to Start Meditating?
Find yoga studios that offer guided meditation, mindfulness classes, and contemplative practice.
References
- Brewer, J. A., et al. (2011). PNAS. "Meditation experience is associated with differences in default mode network activity and connectivity."
- Davidson, R. J., & Lutz, A. (2008). IEEE Signal Processing Magazine. "Buddha's Brain: Neuroplasticity and Meditation."
- Goyal, M., et al. (2014). JAMA Internal Medicine. "Meditation Programs for Psychological Stress and Well-being."