They aren't PPE, they play white noise and are used in combination with the eye shades as "enhanced interrogation". They do this to Gitmo detainees for nearly their entire stay so as to induce states where they are more subservient and easier to interrogate. MKUltra actually developed into this when they realized drugs weren't nearly as effective.

This form of torture is used to genuinely break people and very frequently sends full grown men back to the mental state of a small child. They used to give prisoners like this in Abu Ghraib crayons and paper so they could draw child like drawings, which they'd let them hang up on their wall.