When the headset comes off, though, it’s back to a dreary reality. And lately van Schneider has been noticing some unsettling lingering effects. “What stays is a strange feeling of sadness and disappointment when participating in the real world, usually on the same day,” he wrote on the blogging platform Medium last month. “The sky seems less colorful and it just feels like I’m missing the ‘magic’ (for the lack of a better word). … I feel deeply disturbed and often end up just sitting there, staring at a wall.”

Van Schneider dubs the feeling “post-VR sadness.” It’s less a feeling of depression, he writes, and more a sense of detachment. And while he didn’t realize it when he published the post, he’s not the only one who has experienced this. Between virtual reality subreddits and Oculus Rift online forums, there are dozens of stories like his. The ailments range from feeling temporarily fuzzy, light-headed, and in a dream-like state, to more severe detachment that lasts days—or weeks. Many cases have bubbled up in the last year, likely as a response to consumer VR headsets becoming more widely available. But some of the stories date as far back as 2013, when an initial version of the Oculus Rift was released for software developers.

“[W]hile standing and in the middle of a sentence, I had an incredibly strange, weird moment of comparing real life to the VR,” wrote the video-game developer Lee Vermeulen after he tried Valve’s SteamVR system back in 2014. He was mid-conversation with a coworker when he started to feel off, and the experience sounds almost metaphysical.