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Human Sense of Smell Underestimated
Benjamin Long writes to note a study, by a team of neuroscientists and engineers, that demonstrated that humans can follow a scent trail — an ability that most had assumed only animals possessed. Furthermore, the study demonstrated for the first time that humans make use of differential information from the two nostrils. The researchers blindfolded college students who crawled through grass to sniff out a chocolate-scented trail. Here is the abstract of the paper in Nature Neuroscience. From the article: "The humans, however, still sniffed much more slowly than dogs, which may partially account for canines' greater efficiency at scent tracking. [A commentator] says that despite their relatively sluggish speed, the fact that subjects improved with training is noteworthy. 'I think that shows the effect of our distinctively different behavior in actually using this sense,' he says. 'The dog [has] been doing this its whole life, and humans [were] just asked to plunge in the first time they've ever done it.'"
The researchers blindfolded college students who crawled through grass to sniff out a chocolate-scented trail. This just proves students will do anything for $10
If you can read this, it's already too late.
I was standing behind the server racks and I thought I could sqeeze off a silent fart without anyone noticing. Sadly the offending trouser bomb got caught up in the fans of a 4U Server. The cheese-scented ass gas was recirculated through every fan in the room evenly distributing its greasy essence all over the datacenter. None of my fellow technicians will speak to me since this awful and embarrassing emission.
The following replies are posted by unwashed nerds.
Most women can follow a chocolate scented trail, oddly enough the scent trail left by diamonds and currency works just as well. On the flip side most men are able to scent track women so I guess there's balance in nature.
that demonstrated that humans can follow a scent trail -- an ability that most had assumed only animals possessed.
Err, I recently smelled something burning. I walked through my house using my nose to follow the scent trail, and locate the single light bulb in the chandelier that had a tiny piece of plastic stuck to it that was burning (from a Christmas decoration).
How do these researchers think I performed this amazing feat? Got out my hound dog and had him sniff around?
Sometimes it's best to just let stupid people be stupid.
They eventually found the 'chocolate' left behind by the dog.
...no one knows you're a dog. Until you start bragging about your scent-tracking superiority, then you've given away the game.
I, for one, can't even smell my own breath.
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Maradona has proved it many times some years ago keeping track of some white dust...
I heard about this on NPR yesterday. The researcher said we smelled in stereo. They proved it by plugging up one nostril at a time and then attaching a device so that both nostrils could smell in mono. The test subjects took far longer to find stuff. He also said one people got attuned to smelling a trail they were limited to the speed at which they could crawl.
Richard Feynman did a number of smell experiments with his first wife, Arlene. He would leave the room and she would handle bottles and books then he'd return and see if he could determine which ones she'd touched. He was able to find them. It's detailed in Surely Your Joking, Mr. Feynman .
There! And I didn't make any smelling cracks about misunderestimating or Uranus or "once you get past the smell it tastes all right".
"You'll get nothing, and you'll like it!"
How do you think I find my way to the computer science classroom?
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
It's not evident from the slash summary - but one interesting discovery is that we actually smell in stereo - hence two nostrils.
That comes as a surprise to me - our other stereo sense organs (eyes and ears) are placed just about as far apart on our heads as is structurally possible - but our nostrils are really close together. OK - we don't have a really great sense of smell and we don't rely on it at all - but dogs clearly do - and their nostrils are also very close together.
You'd think we (or at least dogs) would have nostrils mounted just below our ears.
Weird.
www.sjbaker.org
When I was young I used to hate that stuff, especially because my mom would throw blocks of it in the curries without powdering them. One bite of that chunk, and you will curse everyone in sight. So enraged I was, that I once stole her entire stash of asafoitida. I wanted to throw it away in garbage, but I was young and scared and did not dare throw it all away. So I hid it in a trunk in the loft. And, yes as I said in the subject line, my mom sniffed it out and found the stash. So yes, humans can sniff out very aromatic substances. But faint traces like a dogs do [note the significant absence of the apostrophe after the s in dogs] ? I am not so sure.
sed -e 's/Chuck Norris/Rajnikant/g' joke > fact
Benjamin Long writes to note a study, by a team of neuroscientists and engineers, that demonstrated that humans can follow a scent trail
My first job after graduating from college was working as a computer programmer at a US Air Force base. I worked in the main building for our section of the base and our colonel one day was having a VIP come by to visit him. He walked out to the main area and smelled something burning. Convinced that his canine sense of smell had saved the day and wanting to show off for his visitor, he promptly called the base fire department and demanded that they send a truck out to investigate "the burning wires smoldering within one of the walls". The base fire department dispatched a truck and the firemen investigated and told the colonel that what he smelled was burnt popcorn from the break room and there was nothing smoldering within the walls. The colonel then did the only thing that a military man who has just embarassed himself could do. He promptly banned microwave popcorn.
Pictures pls.
A guy is on an elevator alone.
A beautiful girl gets on.
He says "Hey, can I smell your pussy?"
She says "NO!".
He says "Oh, must be your breath."
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
when I quit smoking a few years back after having smoking since I was about 13 (and raised by two smokers) I recovered my sense of smell and taste (they are certainly intertwined)
My sense's of taste and smell are so actute now - it's amazing! I can smell people smoking a few cars in front of me - peoples aftershave and perfumes are most times extreme and putrid (I believe it must be animal urine in them)
The weirdest experience was the re-living of memories evoked through smell, that I had long forgotton. Apparently, smell is the sense most connected to memory, I literally feel younger than ever (36yrs old in reality) Now I can smell the deeper complexities within freshly cut grass that I had completely forgotton. Quit that damn cigarette - you really do get your life back (lots more money too)
In testing to see if humans smell in stereo the best experiment they could come up with is having people follow a piece of scented rope in the grass? All this experiment would prove is that people can smell. If you loose the sent you turn your head to the left or right and if the sent increases, you move in that direction. They went through the extra step of jamming things in people's noses and surprise, people didn't do so well with this teflon contraption hanging off their face.
One thing I noticed, during bootcamp was that my sense of smell became incredibly accute. While, I'll award the reader with the fact that I was a prior smoker to bootcamp, I will say that non-smokers DEFINATELY noticed the difference as well.
While it's not likely we as a society will retort back to nature in a sense, I will say, the body naturally cleans itself and the only reason a "bum" stinks as bad as he does is in relation to all the non-natural environment surrounding him. Not only that, but we are so used to the man made scents, that natural scents tend to stand out even more.
For example... while some city women will think a man from the country is being a sexist pig who treats women like objects... the fact is, men CAN smell women and from a considerable distance away.
OK. Let me stress this, becuase this is when it hit me like a brick during boot camp. It was almost a "holy shit do I have a Marvel Comic superhero nose?", no I don't and you don't either. But, when at a club, a female can be practically touching you and you might smell her perfume. In the work place, a female sitting in the next cubicle might not make her presence known until she makes sufficient noise to catch your attention....
After five weeks into boot camp, a female division walked past the barracks we were at, and walked up stairs. I would accurately judge the distance to about 50 feet away, and every single guy in the barracks literally smelled the girls. We didn't have to hear them. We didn't have to see them. We could smell them and knew they were there. The scents were distinguishable too, not just a generic feminine hormone release into the air. If two girls were in the next room, the guys three rooms down could smell two different scents.
When I was a kid, females weren't allowed to go hunting, irregardless of what time of month or whatever they washed their bodies with. Until boot camp, I always thought it was a wives tale that women gave off that much odor... but I swear to you. Yes, if I am able to smell a female just as well as see her from 50 feet away... then a deer or buck with much better noses can certainly smell a human female from 100 yards away. A man could probably smell the presence of a female much further than 50 feet away, it's just that's the distance I know for a fact and even at 50 feet, the scent was unbelievably strong. How far away before it becomes a hint? The girl might as well have showered in perfume and stood two inches behind me.
Nowadays, away from the lack of everyday luxuries and eminties, inhalation of cigarette smoke, car exhaust, overwhelming stench of plastics and asphalt... no, I couldn't tell you if a girl with no perfume is sitting five feet over in the next cubicle. It's somewhat sad. But, you are capable of doing it. Most people who go on long hunting trips in the wilderness know what I'm talking about. Without all this crap we deal with, this man made crap, nature gave us some pretty interesting abilities that have been long taken for granted or the use is nolonger really needed.
The scent of the girls is what blew me away the most. So vivid, so strong so unexpected. But, I also realized that a lot of other things that might have been overlooked or not processed certainly was while in boot camp. Such as the bed of flowers outside the barracks... yeah, you can smell those things. In modern day life, much of those scents are still hitting our nose, but if they remain being processed it's either at a subconscious level or outright ignored altogether. Anyway, it doesn't surprise me that a group of college students was able to smell a trail of chocolate in the lawn. Doesn't surprise me one bit.
The researchers blindfolded college students who crawled through grass to sniff out a chocolate-scented trail.
Sure... "researchers".
This is one of those weird Japanese game shows!
In the land of the blind, the one-eyed man is kinky.
Crystal Fire and they had an interesting anecdote about the beginnings of semi-conductor research. In the late 1930's early 1940s the scientists at Bell labs were experimenting with silicon to see if they could build rectifiers and other electronic components out of it. At the time there really wasn't any theory about how these things might have worked. Some silicon rods showed semi-conductive behavior, some didn't. Finally they found one rod that showed strong semi-conductive behavior. They couldn't figure out what it was that made this rod special until the scientists and machinist who worked on it said that when it was cut or ground it gave off the same smell as one of the old carbide lamps that were used on many automobiles until the late 1920s. One of the chemists realized that what they were smelling was trace amounts of phospine gas, which meant that the rod has phosphorous in it. This was a surprise as the levels of phosphorous in the sample were so small that they didn't show up in a spectrographic analysis, it was the noses of the scientists and machinist that gave them the clue that the proper trace impurities in silicon would enhance the semi-conductive behavior.
cheap labor conservatives - they want to keep you hungry enough to be thankful for minimum wage.
In the NPR interview with the guys who ran the study, they said that it seemed that the only limit on the speed that practiced humans could track the scent was the speed they could crawl with their noses that close to the ground. That makes sense - I mean you can't crawl along with your nose literally in the grass at any kind of speed at all. A dog is able to run at full speed with it's nose just inches from the ground - and it's eyes are placed so it can still be looking forward as it does it.
So this may have nothing whatever to do with the sensitivity of our sense of smell and more to do with the shape of our head, neck and the length of our fore-limbs.
We mostly evolved to use our sense of smell for detecting whether food has gone bad or not - and for that, having nostrils right above our mouths is plenty good enough.
Dogs are evolved to track prey and find carrion - they need to be able to sniff and run at the same time.
Dog's noses are very impressive...it's incredible to see the kinds of tricks they can manage. But I wonder where that statement of "a million times more sensitive than humans" comes from - I bet it's something some journalist guessed at 100 years ago that we are all passing on as if it were the definitive answer. This study suggests to me that some simple practicing could narrow that gap considerably.
www.sjbaker.org
Richard Feynman (famous caltech physicist) documented his observations of this in his autobiography too; where he demonstrated for friends that he could smell out recently handled books in a book case.
Many people who suspect their spouses of affairs also observe this ability too (knowing in which rooms a guest's been in).
This shouldn't be a surprise to anyone; and it's pretty sad that the obvious gets passed as new, novel research.
Wrong.
The "tongue map" is a myth, and there is a fifth sensor, "unami" (MSG), and possibly a sixth for fats.
... for the psych experiments at my school. The form we all signed said we did it of our own free will. Failing our psych class if we didn't surely didn't motivate us in any way.
I only look human.
My mother is a halfling and my dad is an ogre, so that makes me an Ogreling
There are already highly trained human noses already out there
For example, experienced sommeliers and cheesemongers probably have even more fined tuned senses of smell (at least within their areas of expertise) than most pet dogs. Not blood hounds, mind you, but especially sight hounds and working dogs. Being able to identify ten or twelve different aromas and tastes within one glass of wine is a distinct skill, and I doubt many dogs can do it.
At least, I know mine can't. But then, he can be a mean drunk, so maybe that's the real problem.
God invented whiskey so the Irish would not rule the world.
I remember reading (somewhere) a scent-related experiment which was suggested for kids. The purpose was to demonstrate that people can differentiate the odors of other individuals even though they don't consciously smell anything at all.
The procedure went something like this:
Distribute a freshly-cleaned T-shirt in a zip-lock bag to all participants. Groups trying this experiment should be small, less than 10 people. Each person should bathe in the evening and wear the T-shirt overnight, placing it back into the zip-lock bag in the morning (no distinctive folding or rolling, just shoved in). When everyone is back together again, the bags are gathered while a non-participant draws numbers from a hat, writing the number on the bag and recording who brought it. The number correspondence is kept secret. Bags are then passed around and participants try to guess who wore each shirt.
The article I was reading said that you should expect "uncanny" accuracy, the difference in scent seeming like a "hunch" or a "feeling" rather than a conscious recognition.
Now the even weirder part. A similar experiment was done where the shirt-wearers were unknown to the sniffers. The people smelling the shirts were given a set of photographs, and asked which one the shirt seemed to belong to. Apparently, they scored correctly by a significant margin.
Now, since I'm busy I'll just leave it up to the reader (and Google, perhaps) to find the sources.
The ten dollars you would have earned could be exchanged for many chocolate bars.
Explain how?
The libertarian solution to the failures of capitalism is to apply more capitalism til the failures are fixed.
What about the ability of our sense of smell to make us remember things?
It's very strong with me, almost to a crazy point. Smelling a fragrance that I associate with someone makes me remember them (almost jolts me) much more than anything else, even seeing a picture of that person.
While I'm not surprised that humans can track a scent, and I'm certainly not surprised that civilization may have interfered with this ability, I'm just not sure it's one of our areas of specialization. Your average garden-variety scent hound has more scent receptors, packed into a much larger area, stashed inside that world-class smeller. His entire face, including his long, floppy ears and all those wrinkles (if he has them), is intended to funnel all that scent up into his wide nostrils, where he can interpret and act on it. I've long imagined that at the dawn of time, the human/dog interaction may have gone something like this:
Dog to Human: Wanna go get some meat?
Human to Dog: Yeah. You run on ahead, don't forget to let me know where you are, and I'll follow along with this stick. I just figured out how to put some sharp flint on the end of it. Should do a good job of killing that gazelle or whatever it is.
Dog to Human: AROOO!
Later that same evening...
Human to Dog: Get away from that! Let me hack it up with this sharp piece of flint.
Dog to Human: Good job! If you don't mind, I'll just gorge myself on the leftovers so I can go home and regurgitate some for the wife and pups.
Human to Dog: Yeah, I'm taking the good parts. My wife has been gathering some kind of green stuff, and she'll put it on the meat and apply fire to it. Good eating!
No wonder humans are generally so fond of dogs. We're hunting buddies from way back.
"Here's what's happening. You're starting to drive like your Dad..." - Red Green
If you can read this sig, you're too close.
As a new mom I was surprised (and not especially happy) to discover that, on entering a daycare room filled with toddlers, I could right away determine that MY toddler was sporting a full diaper load. Many moms with kids that age report the same experience. There's nothing like dealing with your own babies to make you realize what an animal you REALLY are.