#3. Change Your Moods
Maybe it's not a vivid memory that assaults you out of nowhere, but a feeling, or a mood. You're sitting there, minding your own business, when suddenly you're overcome with dread, or anxiety, or anger. Once again, there's a good chance a faint smell is at play, triggering your subconscious.
Fans of aromatherapy are always talking about "relaxing" scents, but the nose is actually way more useful when it comes to making you anxious, or alert. It works in a good way, too -- studies of "pupillary fatigue oscillations" (a sciencey way of measuring tiredness) found that people exposed to a peppermint scent stayed awake longer than those without it, and people given periodic doses of peppermint smells performed better on tasks requiring a high level of concentration.
"Goddammit, Steve, this looks like a two candy cane vault."
Bad smells not only decrease how well people do at complex tasks, but also have a negative effect as severe as you'd get from exposing people to a distracting noise. Well, duh, you say. So people couldn't concentrate because they were distracted by the stench. That's why it's so hard to study on public transportation! But the point is that the smells had the effect even when at such a low level that the subjects couldn't consciously detect them. We're telling you, it's like mind control over here.
"I'm sorry, but does someone in here have a full bladder?"
It's down to something called olfactory conditioning: You pair up a smell with something that causes a reaction, and later on that smell will cause a repeat of that reaction, even if the original cause is gone. And we're not talking about obvious things, like the way Rambo freaks out at the smell of napalm. You can actually change the blood glucose levels of diabetics by introducing a smell that you've paired up with giving them insulin in the past.
Like the smell of sugar if it's pressed into their nose, and they sniff really hard.
As for the feelings of anxiety, for whatever evolutionary reason, we are a lot better at detecting and remembering smells when we're in situations that feel dangerous, stressful or emotionally charged. Maybe it helped us remember the smell of bears.
Fun fact: An angry grizzly smells a lot like you pooping yourself.
But the connection between smell and emotion gets stranger still. Your sense of smell can actually ...
#2. Drive You Crazy
There are many things generally accepted as risk factors for depression: genetic predisposition, bad diet, lack of exercise, living in Oregon. But there's another depression predictor that's less well-known: how well you can smell things.
You would think that people who develop anosmia, or lack of smell, get off relatively easy in the big scheme of things. At least visiting public toilets must be easier, and that pretty much cancels out the bad stuff, right? But anosmic people have a high risk of severe depression, and it's not just because they're sad about losing one of their five senses. It's much weirder than that.
It's because they have horse souls.
Studies of depressed people have shown that they tend to have a reduced sense of smell and a smaller olfactory bulb. In fact, one of the easiest ways to bring about depression in lab rats (in order to say, test antidepressant drugs on them, or just because you really hate rats) is to remove their olfactory bulb. De-smelled rats immediately become lethargic, listless and uninterested in rewards or grooming, and they start listening to Morrissey on their teeny tiny little rat headphones.
And if that doesn't have you nervously sniffing the air to find out whether you'll want to get out of bed tomorrow, a bad sense of smell and small olfactory bulb are also correlated with schizophrenia.
Don't tell him, but that painting is made out of ketchup.
That is how strongly your moods are tied to your sense of smell. Scientists don't perfectly understand the link between sense of smell and mental illness, but we know that depression and schizophrenia both involve persistently flat moods. Apparently if one link in that chain that connects smell and emotions breaks, the whole thing falls apart. Or it could work in the other direction -- if your sense of smell disappears after a lifetime of smell/emotion connection, and all of these subconscious emotional triggers disappear along with it, the flat numbness that results could bring about the depression.
Whatever the connection, it's so strong that scientists are now making "scratch and sniff" tests to predict people's future risks for schizophrenia, obsessive-compulsive disorder and other illnesses. No, really.
"No, ham! I meant ham!"
#1. Make You More Attractive (But Not in the Way You Think)
Entire multibillion dollar industries are built upon the idea that smelling good gets you dates (smell can also influence who you're attracted to). But when we say that your sense of smell can make a man more attractive to the ladies, we're not just pointing out that a quick sniff test of one's clothing before heading out is a reliable start on the path of not dying alone. And we're not talking about those pheromone sprays that promise to make women ignore the crumbs caught in your neckbeard.
No, this is weirder.
Because horse souls smell like fucking.
In a recent study conducted by the University of Liverpool, they had some guys spray themselves with Lynx (the English version of Axe Body Spray). Then they had women rate the men's attractiveness ... via videotape. As in, they were out of smelling range. The men who sprayed themselves down were still rated as more attractive, even though the women couldn't smell them.
According to the scientists running the experiment, the power was inside the men the whole time. The guys given the scented spray figured they smelled good, so their body language displayed more confidence, and the women who watched them responded to that.
"You don't have to tell me. Johnny Beardface already knows, baby."
So does this mean these dudes were just brainwashed by Lynx's marketing campaign? They actually believed the ads that claim spraying this stuff will have women diving for their junk?
Nope -- the can of spray used in the experiment was unmarked, so the men had no idea what kind of deodorant they were covering themselves with. It seems like pretty much anything that doesn't actually smell like mustard gas will do the trick. It turns out the amazing mind-control powers of smell aren't about making the girl at the bar swoon -- it's about tricking yourself into having a little confidence for once.
"I ... I'm just shy. I can't help it."
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