One fairly common idea that pops up again and again during the endless national conversation about college campuses, free speech, and political correctness is the notion that certain forms of speech do such psychological harm to students that administrators have an obligation to eradicate them — or, failing that, that students have an obligation to step in and do so themselves (as has happened during recent, high-profile episodes involving Charles Murray and Milo Yiannopoulos, which turned violent).

Such claims of harm — often summed up as "speech is violence" — aren't typically invoked in response to actual Nazis, or anything like that. Rather, they are used to argue against allowing speakers like Murray and Yiannopoulos — who, for better or worse, do fit in the conservative mainstream — or even significantly more moderate ones like Emily Yoffe, who has expressed skepticism about certain claims pertaining to the prevalence of sexual assault on campus. In one instance students successfully canceled a showing of American Sniper by arguing the film's ostensible Islamophobia would make "students feel unsafe and unwelcome" — though the screening was later uncanceled.

Now, given the fog of culture war that has descended on this subject and the tendency of opportunistic (mostly) conservative outlets to hype these kinds of events, it isn't clear how common they actually are — people often forget the polls suggesting that college students, broadly speaking, tend to hold pro-free-speech views. But either way, it is hard to take seriously the idea that an American Sniper showing or an Emily Yoffe appearance, or even a Yiannopoulos talk, is so potentially psychologically harmful that established norms about free expression — which protect both College Republicans and Palestinian students advocating on behalf of their people — should be tossed out the window.

So it was weird, in light of all this, to see the claim that free speech on campus leads to serious psychological harm being taken seriously in The New York Times, and weirder still to see it argued in a manner draped in pseudoscience. Yet that's what happened. In a Sunday Review column headlined "When Is Speech Violence?" Lisa Feldman Barrett, a professor of psychology at Northeastern University, explained that "scientifically speaking," the idea that physical violence is more harmful than emotional violence is an oversimplification. "Words can have a powerful effect on your nervous system. Certain types of adversity, even those involving no physical contact, can make you sick, alter your brain — even kill neurons — and shorten your life." Chronic stress can also shrink your telomeres, she writes — "little packets of genetic material that sit on the ends of your chromosomes" — bringing you closer to death.

In light of all this, she wrote, it makes sense to think seriously about banning certain campus speakers:

The scientific findings I described above provide empirical guidance for which kinds of controversial speech should and shouldn't be acceptable on campus and in civil society. In short, the answer depends on whether the speech is abusive or merely offensive.

Offensiveness is not bad for your body and brain. Your nervous system evolved to withstand periodic bouts of stress, such as fleeing from a tiger, taking a punch or encountering an odious idea in a university lecture.

[…]

What's bad for your nervous system, in contrast, are long stretches of simmering stress. If you spend a lot of time in a harsh environment worrying about your safety, that's the kind of stress that brings on illness and remodels your brain. That's also true of a political climate in which groups of people endlessly hurl hateful words at one another, and of rampant bullying in school or on social media. A culture of constant, casual brutality is toxic to the body, and we suffer for it.

That's why it's reasonable, scientifically speaking, not to allow a provocateur and hatemonger like Milo Yiannopoulos to speak at your school. He is part of something noxious, a campaign of abuse. There is nothing to be gained from debating him, for debate is not what he is offering.

This is a weak and confused argument. Setting aside the fact that no one will ever be able to agree on what's "abusive" versus what's "merely offensive," the articles Barrett linked to are mostly about chronic stress — the stress elicited by, for example, spending one's childhood in an impoverished environment of serious neglect and violence. Growing up in a dangerous neighborhood with a poor single mother who has to work so much she doesn't have time to nurture you is not the same as being a college student at a campus where Yiannopoulos is coming to speak, and where you are free to ignore him or to protest his presence there. One situation involves a level of chronic stress that is inflicted on you against your will and which really could harm you in the long run; the other doesn't. Nowhere does Barrett fully explain how the presence on campus of a speaker like Yiannopoulos for a couple of hours is going to lead to students being afflicted with the sort of serious, chronic stress correlated with health difficulties. It's simply disingenuous to compare the two types of situations — in a way, it's an insult both to people who do deal with chronic stress and to student activists.

It's also worth pointing out that this sort of scaremongering — Milo is coming and he is shrinking your telomeres! — could become a self-fulfilling prophecy for some students. There's an intriguing area of behavioral science known as mind-set research, and one of its tenets is that the relationship between stress and humans' response to it is partially mediated by how people expect stress to affect them. In one intriguing study, for example, a group of Australian college students were given a psychological test and then told — at random — that it revealed they were either good at dealing with stress or bad at it. Then they watched, on a MacBook, a very disturbing 10-minute video of a car wreck, after which they were asked to "close their eyes and relax" for three minutes.

When they opened their eyes, the researchers running the study asked them to estimate the number of times the film's sounds and images intruded on their consciousness during the interlude, and how distressing they found the film overall. As it turned out, the students who were told at random they were good copers were less affected by the film — they experienced, on average, about four and a half intrusions during the three-minute interlude, and rated their distress level at 5.65 on a 10-point scale. The "poor copers," on the other hand, experienced about 18 intrusions and rated their distress level at almost an 8. It's an interesting finding — albeit one conducted on a fairly small sample of 33 students — and there are other studies which also suggest that the way we are primed to respond to stress can affect how we eventually do.

Now, it would be just as much of a stretch to say that a single column like Barrett's could cause students to self-traumatize as it would be to say that an upcoming Yiannopoulos appearance could traumatize them. But in the aggregate, if you tell students over and over and over that certain variants of free speech — variants which are ugly, but which are aired every moment of every day on talk radio — are traumatizing them, it really could do harm. And there's no reason to go down this road, because there's no evidence that the mere presence of a conservative speaker on campus is harming students in some deep psychological or physiological way (with the exception of outlying cases involving preexisting mental-health problems). This is a silly idea that should be retired from the conversation about free speech on campus.

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