I use to listen to nature sounds cds and youtube videos a lot when I was an undergrad and a graduate student. They worked for me and they helped me concentrate better, not only were they relaxing but I actually performed better in examinations. My favorites are dolphin and whale sounds. I use it now to help me with insomnia bc unfortunately I’m going through another bout of sleepless nights and thus far this has been the only thing that has proven effective even if I’m unable to sleep the entire night.
Nature Relaxing Sounds