"Bringing in an external person has allowed staff and outside suppliers to speak plainly and many of the messages being conveyed are uncomfortable and challenging ones, " he said.

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Andy Newberg, MD at the University of Pennsylvania has found that both in meditating monks and in praying nuns, areas of the brain important in concentration and attention were activated, while areas that govern how a person relates to the external world were deactivated.

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The color red is believed to increase receptiveness to external stimuli, which could affect a person's emotional and motor responses, researchers said.

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Sometimes the bacteria are external, but in some cases, the person is already carrying the bacteria on them or even inside them.

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"Change and the external swirl that goes along with it are never easy, " he said, according to a person familiar with the matter.

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The combination of the mental activity and the external stimulus is believed to aid in reprocessing traumatic memories in ways that reduce their pain and damage to a person's life.

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