The smell stops you in your tracks. Cut grass and roasted meat. Norsca shampoo. Red Door perfume. That person, who just walked past you, is trailing the scents of your childhood. One whiff, and once more, you are 9 years old.
You've been "triggered".
A sensory stimulus has tripped your mind's memory tape and transported you back in time. But what if what you had just smelled was the aftershave of the man who sexually abused you?
Sight, sound, smell, touch and taste can all trigger traumatic flashbacks. So can words. And right now, battle lines are being drawn around attempts to limit exposure to words that could rekindle past trauma.
It's a move that started online and has spread, controversially, to major American universities. In New Zealand, it is employed mainly by bloggers and internet-only news websites. It's a simple phrase. Two words, meant to caution you against all the other words: "Trigger Warning".
Last year, The Atlantic reported students at one American university had requested a "trigger warning" be applied to F. Scott Fitzgerald's The Great Gatsby, so its portrayals of physical abuse and misogyny might be avoided by those who had previously experienced domestic violence.
In The New Yorker, Jeannie Suk, a Harvard law professor, wrote that student organisations had asked teachers to warn their classes the rape-law unit might "trigger" traumatic memories.
"Some students have even suggested that rape law should not be taught because of its potential to cause distress," Suk said.
On local websites, Canvas found the phrase prefacing opinion posts about everything from men's rights activists to sexual assault; infertility to Isis.
An R15 dance performance on Waiheke Island, subtitled "issues that youth are faced with today" was slapped with a Trigger Warning and an extended explainer: "Subject matter includes suicide, exploitation, mental illness, domestic violence, war and sexual references."
This is not the "graphic content" descriptor from television programmes or even stories on nzherald.co.nz. It's not a rating system or a cautionary note for parents to monitor what their kids are watching. It is a specific phrase rooted in a specific psychological definition: The content you are about to consume could make you relive something unpleasant.
Trigger warnings have been called "useful signposts". But some caution the phrase is being applied too broadly, and an excuse for avoiding debate.
When should a trigger warning apply? One blog that lists topics where it should be applied as a "common courtesy" includes everything from suicide, abuse and discussion of "isms". Its 30 headings run from pregnancy, vomit and fat-shaming, to spiders, blood, "slimy things" and calling people stupid or dumb.
Last month, the Merriam-Webster dictionary added "trigger warning" to the 2000 new words and phrases it considers constitute the English language. It's official. But can two words really protect someone from reliving a past trauma?
A few months ago, Lizzie Marvelly, the Herald columnist who has just gone public with her experiences of sexual harassment in the local music industry, was a self-described "vehement defender" of trigger warnings.
As she wrote on her website Villainesse.com, "the idea of preparing readers in advance for material that may be stressful or offensive seemed like common decency to me".
Then she came across an online story about sexual abuse. It was prefaced with a trigger warning. She read it anyway. Afterwards, Marvelly reflected: "What I realised, was that the trigger warning itself automatically brought my reference points to the fore. It was almost like the trigger warning made sure all of my demons were in the audience before the show began."
She started to rethink her position - on the morning she spoke to Canvas, she had gone through Villainesse.com and removed the phrase "trigger warning" from posts entitled "Isis: Explained" and "What is Boko Haram". Her rationale? "With those two headings, we know what we're in for."
Marvelly says the arguments for and against the "trigger warning" label are complex. "We don't want anyone to read something and feel dreadful and have a flashback, but it's balancing that with where do you draw the boundaries?
"My worry is that, in some ways, it can be patronising. For someone who has experienced sexual violence, it could be read as a writer or an editor going, 'hey, you might be triggered by this - you might not be able to handle this'.
"The worry for me is that trigger warnings take agency away from the individual. They're a little bit paternalistic."
Marvelly does not - as some overseas commentators have - equate trigger warnings with censorship.
"But they are on that spectrum. There's an argument that they empower people to know what's coming, and I would potentially agree with that. I get the need for them; I get it as someone who has had experiences that some pieces [of writing] do trigger some uncomfortable memories of. But also, life is triggering. You can be walking down the street and have a flashback."
A not-so-brief history of the trigger warning compiled by BuzzFeed, tracks the evolution of the phrase from clinical psychology (where it was used in relation to sufferers of Post-Traumatic Stress Disorder) to fan fiction to social media sites to mainstream media and university course descriptions.
Its use has most recently and famously been decried by British comedian and actor Stephen Fry who told a US television show that people who demanded trigger warnings on classic texts needed to stop feeling sorry for themselves and "grow up". He later apologised.
In The Atlantic, it's theorised the trigger warnings are a consequence of over-protective parenting. A generation that grew up being driven to schools where peanut butter was banned and dangerous structures were removed from the playground, was always going to enter university "desirous of protection".
Marvelly disputes that: "I don't think we are that cotton-woolled. I think there are some quite significant dangers that we've had to deal with. Cities are bigger, there are more people, the crime rate is higher." The jury, for her, is out.
"A lot of people feel very passionately. They believe everything should have a trigger warning. I'm not saying that's wrong. I'm saying for me, I find that a little uncomfortable. I think that's me saying 'hang on, I can deal with that stuff'."
The modern-day use of the phrase is most commonly linked to narratives involving sexual abuse or violence; it appears routinely on feminist blogs. Canvas found it referenced on the New Zealand Women's Refuge Facebook page. Which you'd expect, right?
"We use it incredibly sparingly. Probably only a couple of times maybe in the last 12 months," says Dr Ang Jury, Women's Refuge chief executive.
"Let's give people a little bit of credit, I think. People aren't little sponges who get offended and upset by everything they see . . . I don't actually want people avoiding images that make them angry when it comes to things like sexism or homophobia. We need people to be concerned about these things."
Jury says words like "rape" should not be hidden.
"That is ridiculous. Those words are an accurate representation of an event. They are words that have meaning. If somebody has been raped, they have been raped. Not talking about it, or using euphemistic language or trying to hide that fact, is not going to change the fact that person was raped."
But what if someone wanted the opportunity to opt out of a reading something potentially "triggering"?
"I'd be wanting to know why they're looking to opt out. There's clearly something going on for that individual if hearing the word 'rape' is going to trigger them. That's not to say it wouldn't be potentially awful for them. But you can't hide away from stuff."
She is concerned the phrase has been over-used.
"Let's not empty this notion of all utility, or we run the risk of it becoming just another term that means not very much. Let's save it for the things that really matter."
Ekant Veer is the Canterbury University associate professor of marketing who, in 2014, handed back his Lecturer of the Year Award in protest at the Student Association's apparent inability to reign in sexism and racism on campus.
That same year, he showed an exhibition of photographs in Helsinki, Finland, titled I'm Struggling [Trigger Warning]. Veer says he used the label because some of the images dealt with self-harm.
"I was going to be presenting work that may potentially trigger traumatic experiences."
While Canvas spoke to local university lecturers who routinely apply cautions (though not the specific phrase "trigger warning") to course material covering issues like self-harm, sexual violence or addictions, Veer says he has seen no evidence of anything like the American university experience being played out here - partly, he thinks, because New Zealand culture is less litigious and student fees are lower.
"In America, if I pay for something, you owe me everything. And if I've given you $100,000 [for an education] you will do everything I say."
What Veer has observed here, however, is the misuse of the word "triggering", particularly online, where it is used to shut down debate.
"It's not a word you should throw around, or say 'I'm being triggered' just because you're upset or someone said something controversial or counter to your own perspective . . . 'I was hurt' or 'I was upset' is not the same as being triggered . . . you're actually nullifying the impact of the word.
"If you disagree with someone in a debate online and they say 'I'm being triggered' you have to stop and think: Is the onus on me as the person communicating, or is the onus on the person receiving the message?"
Because, says Veer, there's another phrase that might also usefully be employed: "Just because you're offended, doesn't mean I've been offensive."