In the 200,000-year history of anatomically modern humans, the cerebral hemispheres have a long history of productive co-evolution. The inclusive and empathic right hemisphere is attuned to the social and emotional sounds of speech, to music, all the subtleties of relationship and holistic processing. The great skills of the left hemisphere are linguistic consciousness (the re-presentation of life in words), mathematics and motor control of the dominant hand (hence, the making of complex tools).
When you teach people to use awareness to intentionally focus attention, you not only change the function of the brain, you change its structure. That is the phenomenon of neuroplasticity. In other words, when we meditate, the brain is re-wiring itself.
Neurological integration in the brain is the linkage of differentiated parts, and this affects the functional relationship between the left and right hemispheres. Social relationships that honor differences while promoting linkages also cause the brain to become more integrated, and that looks a lot like harmony. The un-integrated state is characterized by chaos and rigidity.
Via Pamir Kiciman