Two informative websites:
What are Brainwaves?
https://brainworksneurotherapy.com/what-are-brainwaves
Re-programming life; Secret files on telepathy. - Theta 4-8hz
https://re-programming-life.blogspot.com/2018/11/secret-cia-files-on-telepathy.html
Russian Ministry of Defense article claims humans can telepathically communicate with dolphins. ( article by Arjun Walia, CE)
https://www.collective-evolution.com/2019/11/07/russian-ministry-of-defense-article-claims-humans-can-telepathically-communicate-with-dolphins/
(There's a lot more information about these topics nowadays, but alas, I don't have much spare time.)