Mass Mind Brain Damage
Not just personal brain damage, not just one individual brain damage.
Brain damage of entire groups, mass mind brain damage. Mass man brain damage.
Reference:
“The Galaxy Reconfigured or the Plight of Mass Man in an Individualist Society” - Marshall McLuhan
"Global Brain: The Evolution of Mass Mind from the Big Bang to the 21st Century" - Howard Bloom
It's the culture.
The essential idea in Patterns of Culture is, according to the foreword by Margaret Mead, "her view of human cultures as 'personality writ large.'" Each culture, Benedict explains, chooses from "the great arc of human potentialities" only a few characteristics which become the leading personality traits of the persons living in that culture.