It might be William Gibson's short story Hinterlands. A portal is discovered in the space between Earth and Mars. Those few that are taken through the portal come back insane or dead by their own hand. Sometimes they also bring back invaluable alien tech, so a program is developed to keep sending people and trying to help the ones that come back.
“Ever wonder how they thought this scam up, Toby?” She was squinting
into the sunlight, east, down the length of our cylindrical country,
horizonless and green. “They must’ve had all the heavies in, the
shrink elite, scattered down a long slab of genuine imitation
rosewood, standard Pentagon issue. Each one got a clean notepad and a
brand-new pencil, specially sharpened for the occasion. Everybody was
there: Freudians, Jungians, Adlerians, Skinner rat men, you name it.
And every one of those bastards knew in his heart that it was time to
play his best hand. As a profession, not just as representatives of a
given faction. There they are, Western psychiatry incarnate. And
nothing’s happening! People are popping back off the Highway dead, or
else they come back drooling, singing nursery rhymes. The live ones
last about three days, won’t say a goddamned thing, then shoot
themselves or go catatonic.” She took a small flashlight from her belt
and casually cracked its plastic shell, extracting the parabolic
reflector. “Kremlin’s screaming. CIA’s going nuts. And worst of all,
the multinationals who want to back the show are getting cold feet.
‘Dead spacemen? No data? No deal, friends.’ So they’re getting
nervous, all those supershrinks, until some flake, some grinning
weirdo from Berkeley maybe, he says,” and her drawl sank to parody
stoned mellowness, ” ‘Like, hey, why don’t we just put these people
into a real nice place with a lotta good dope and somebody they can
really relate to, hey?’ ”