While dancing they are oblivious to their surroundings, they shriek, scream, and rave – note the use of ‘rave’ in its older meaning of manic behaviour – and they have visions which ‘according as the religious notions of the age were strangely and variously reflected in their imaginations.
A book by Robert Mullally is answering a part of this question, detailing one of the most popular dances of the Middle Ages.
The early Church had a mostly critical attitude towards the dance. It was said that those who dance cherish heathen godheads and that they allow their bodies rule over their minds. Repeatedly, the synods prohibited religious dances and/or dances within churches.
The following article is about repression, and how repressed culture can find expression in legends.