I have had the same issue... Pressing and holding 'X' as you'd normally do does not appear to work for me. I have tried replaying the mission multiple times, but it appears there is no work around. Since it's a "side mission" I am just going to progress without finishing this mission. But it is quite annoying to be locked in the brain dance... the only way out seems to be quit the game, it won't let me load a saved game while stuck in the BD. So I quit the game... load a previous save and continue on. Hopefully the CDProjektRed crew will get this figured out, in the near future.