This is a simple technique used by some people to help with their listening.
How does it work?
By closing your eyes you block out any visual distractions.
Because you don’t see anything, your brain is free to focus on listening.
Your attention is completely focussed on thinking about the sounds.
People argue that it helps you to hear more details in the sounds.
Fact
Karlheinz Stockhausen used to provide blindfolds for his audiences to cover their eyes.
BUT, it doesn’t work for everyone
Not everybody believes that this works. The composer Simon Emmerson keeps his eyes open when he listens to sounds.
You should try it for yourself. If it works then you have a great simple tool to help you with listening, but don’t worry if it doesn’t work for you. You can still listen in great detail while keeping your eyes open.
References
Simon Emmerson (2007) Living Electronic Music. Ashgate Publishing, London. p.168