The light and dark half circles just outside the central hub represent the ways we can act in any situation. The light segment has happy peaceful human beings moving upwards, representing the effects of our actions (karma) when rooted in compassion, generosity and awareness. The dark half has human brings plunging downwards with expressions of horror and terror on their faces, representing the suffering we eventually experience as the consequence of our negative actions. They are usually depicted naked and chained together, dragged along by a couple of demonic looking beings.