Vulcans are extremely tough and endurable both psychologically and physically and for those reasons I find it exceedingly difficult to believe they wouldn't be able to hold up under the pressure of war.
If you know the behind-the-scenes story, that's exactly why the "Field of Fire" serial killer was a shell-shocked Vulcan solider. That was to indicate: "Holy crap! The war is going really badly if a Vulcans, who came from a culture that encourages training to have great control over their feelings and actions, cracked under the amount of pressure the conflict is putting on the soldiers and other players." Also, not all Vulcans are alike or fit the ideals of their culture and upbringing (heck, ENT showed that in full force), even if they strive for that. T'Pol from ENT had her emotions close to the surface since that was a part of her personality, unlike say, Tuvok, who seemed more suited to the stoic life. Heck, there was the
v'tosh'ka'tur sect in ENT that wanted to embrace both logic and emotion, not just one.
(Also, the Vulcan killer, having cracked, acted pretty consistently within Vulcan culture. When asked why he did it, he said that logic dictated it. While his mind is messed up, to be sure, he was shown to be doing what his damaged mental state thought fit within Vulcan ideals.)
Doesn't mean they're psychologically sounder. Or even superior to human's psychologically Suppression isn't always a good thing.
Never heard of this "neurosuppressor". Where's that from? I thought it was control discipline that kept their emotion's in check. From my recollection they're very passionate and that passion almost killed them. No biological element keeps that in check
There isn't. Now, "Meld" (VOY) does establish that Vulcans have a psycho-suppression system in the brains that can suppress emotions, which maybe what
@Voth commando1 was thinking of. However, that doesn't mean that all Vulcans can automatically stop feeling (in fact, the need for training to be stoic strongly suggests that the brain thing is an aid, not the main method) or that the feature works flawlessly. After all, Vulcans are naturally emotional beings by nature. (And the brain suppressor wouldn't have helped the "Field of Fire" Vulcan much if his mind was already a mess.)
Edit:
I can't recall exactly it was in Voyager I believe.
Yep, see above.