The brain is the center of the nervous system. The brain is more complex than the most powerful computer and has over 100 billion nerve cells.

The brain weighs three pounds, with the consistency of soft tofu. It is made of about 1.1 trillion cells. Most neurons in the brain are firing 5-50 times a second. The brain is 2% of body weight yet uses 20-25% of the body’s metabolic supplies. Even in deep sleep or coma, the brain is busy. It’s like a refrigerator; always on.

We can recognize maybe 4 thoughts per second, if we’re pretty aware. If we get really quiet, we might be able to see 8-10, at the most. So what we think of as thought—this slow, congealed, turgid stuff—is just the tip of the iceberg of mental activity.


The brain is composed of neurons consisting of gray and white matter. The brain is the command center sending impulses up to 170 mph down the spinal column and has nerve ending throughout the body.

Studies have shown that the ways we intentionally shape our internal focus of attention in mindfulness practice induces a state of brain activation during the practice. With repetition, an intentionally created state can become an enduring trait of the individual as reflected in long-term changes in brain function and structure. This is a fundamental property of neuroplasticity—how the brain changes in response to experience.


White and gray.


Like a small very soft melon.


Above the waist.


In the cranium.


Borders of the skull.

Meditation on the Brain