Never heard of this until recently. The Atlas Bone is the uppermost vertebrate of your spine supporting your head.

 It’s named after the mythological Atlas, who carried the world on his shoulders, because it literally supports the weight of your head. Unlike other vertebrae, it’s ring-shaped with no solid body, designed to cradle the skull and let you nod your head “yes” through its unique joint with the occipital bone. It works in tandem with the axis bone (C2) below it to give you that smooth head-turning action.  

There is come controversy though. Apparently in times gone past (if Wikipedia is to be believed) there is some question regarding where the so called 'Atlas Bone' actually is. The early consensus seems to say it is C7 which is roughly where your neck meets your shoulders. The thought is that Atlas bearing the world would have put the brunt of the weight here. 

The more modern belief is C1 which resonates with the belief that the weight of the world is not put on your back, rather your mind (makes more sense to me). C1 is the vertebrae that holds up your head as the first of the spinal cord.

Healthline coins it as the term "emotional baggage" which can change your posture and is arguably heavier than literally holding the physical world. They talk about trapped emotions that can have an effect on your physical health. Trauma can play a role too. We need to think about family, relational, business and governmental impacts that these can have on C1 and other areas of the body.