I thought the same thing at one point, but I've calmed on this episode a bit. It's like what if you suddenly lost your hearing or sight out of the blue. I know if that happened to me, that would scare the shit out of me and I probably would understand what Troi was going through. Still, despite that, it does show a weakness in Sirtis' acting ability, which much improved since. it was a little cringe-inducing at points throughout the episode.