This pattern was repeated throughout the ancient world, for example, pitting Chinese against the peoples of the Steppes, hurling German and Hunnish barbarian races against the Romans, and in countless upheavals throughout Meso-America.

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Generally, acts of self disclosure were accompanied by spurts of heightened activity in brain regions belonging to the meso-limbic dopamine system, which is associated with the sense of reward and satisfaction from food, money or sex.

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