It has been known for some time that exercise modulates BDNF (brain-derived neurotrophic factor), losses of which are implicated in cognitive diseases i.e. dementia + Alzheimer’s .  Makes sense that dance does the same doesn’t it.  An article eloquently exploring the concept: Article

Wikipedia also has a fantastic article on BDNF if you’d like to learn more:

https://en.wikipedia.org/wiki/Brain-derived_neurotrophic_factor