I’m not sure about the precise date I saw this movie. I was young, so it was pre 2000, I believe. It wasn’t 60ies old because I remember some half-decent equipment in it.
I remember that there was a bunch of kids at this institution and that they got this new teenager, male, dying of terminal illness, not sure which one. They connected him on some brain machine and they could see what he was seeing on the monitor. While he was on the edge of death, I remember scientists telling him go into the tunnel which they could see on the monitor, but he kept saying that he doesn’t wanna go inside because it is dark. He went there anyway and his soul got trapped inside of some giant machine which was pulsing. One of the other kids there, some little girl was yelling at scientists to let him go, synchronous with pulsing of the light of the machine. I tried manually browsing wikipedia page of scifi movies from 70ies up to now, but I can’t seem to find it. Could you please help? It would mean a lot. Thanks in advance.