The following post on the benefits and effects on the brain of meditation was originally part of a presentation Eric Thompson gave on the Neuroscience of Meditation at the MindHive event at Naropa University in March, 2010. It is based on the research of Newberg and d’Aquili.

Stage 1

• Attention Association Area (AAA) in the right hemisphere is activated.
• Eventually spreads to AAA in left hemisphere.
• Deactivation of the surrounding areas in the frontal lobes.
• Any burst of activity in these areas indicates the presence of random thoughts.

Stage 2

• Increase in GABA.

• Decreases stimuli arriving at frontal lobe.

• Enhances focus.

• Decreased activity in Orientation Association Area (OAA) in right parietal lobe.

• Right parietal lobe normally mediates our sense of space.

• Decreased activity results in the meditation of a felt sense of wholeness.

Stage 3

The hippocampus:

• Conveys the emotional significance of the experience.
• Imprints long-term memory.
• Activates the right lateral amygdala.

The amygdala:

• Confers emotional significance to the lack of incoming sensory information during meditation.
• Influences the hypothalamus.

Stage 4

The ventromedial hypothalamus:

• Activates the parasympathetic nervous system.
• Relaxation.
• Bliss.
• Profound quiescence.

Activity eventually spills over from the right hemisphere into the left hemisphere:

• Left and right parietal areas (OAA) are then switched off.
• Correlated with the dissolution of the self/non-self boundary.

Stage 5

Activity in the left hemisphere:

• Eventually activates the sympathetic nervous system.
• Arousal.
• Alertness.
• Clarity.

The resulting simultaneous activation of the parasympathetic (Yin) and sympathetic (Yang) nervous systems mediates:

• Stability.
• Equanimity.
• Shamatha.
• Spiritual experiences.