Comments on: These molecules, they vibrate?

These molecules, they vibrate?

louche mustachio — Tue, 11 Nov 2008 19:16:58 -0800

The Science of Scent. An entertaining and enlightening TED talk by biophysicist Luca Turin.

By: louche mustachio

louche mustachio — Tue, 11 Nov 2008 19:17:14 -0800

Previously, previouslier.

By: kisch mokusch

kisch mokusch — Tue, 11 Nov 2008 19:53:07 -0800

Fascinating, I'd never heard such a theory. Thank you.

By: stbalbach

stbalbach — Tue, 11 Nov 2008 19:57:42 -0800

This is crazy far out. It's like something a hippie on LSD would dream up (or 19th century German literature, a reference I didn't understand). But he is able to make accurate predictions with the theory which is really powerful evidence. If we are able to sense molecules based on vibrational frequency, it opens up a whole new way to approach things.

By: nickyskye

nickyskye — Tue, 11 Nov 2008 20:51:48 -0800

Why, oh why do I need sleep? Why can't I stay up until dawn exploring this TED talk? Drat. Will favorite now and watch later. Thanks for the post. Can't wait to watch the vid. On preview, stbalbach, why oh WHY did your comment have to be so interesting and intriguing?! No fair! Want to watch the vid, must sleep. Sleep has to win.

By: afflatus

afflatus — Tue, 11 Nov 2008 21:03:31 -0800

Absolutely read Emperor of Scent about Luca Turin. Amazing book, totally reworked the way I thought about scent and perfume. I have a whole new appreciation of after reading that and went out and bought a hand-made amber oil that perfectly suits me, a guy who had never been one to wear cologne. Great science, great anthropology, great biography.

By: twoleftfeet

twoleftfeet — Tue, 11 Nov 2008 21:15:55 -0800

Thanks! I enjoyed The Emperor of Scent and I was bummed when Turin stopped his blog. Nice to see some new stuff from him.

By: Ambrosia Voyeur

Ambrosia Voyeur — Tue, 11 Nov 2008 23:02:50 -0800

Wonderful! I will definitely look into the book! Dang, I need a perfumery set, too!

By: Dataphage

Dataphage — Wed, 12 Nov 2008 01:04:04 -0800

I enjoyed The Emperor of Scent, and his perfume review book is quite good. After reading both, I spent a Sunday afternoon at Macy's and Nordstrom smelling perfume samples. Usually I only see the inside of such stores when they are burning to the ground in my dreams of revolution. While reading TES, I could never be sure if Turin is a real visionary, and his theories have some meat to them, or if he is a complete crackpot. He even scores some points in the crackpot index. His paper(s) can be found online, but are beyond me. I had the same problem with them that he claims peer reviewers have had (peer reviewers who have always rejected the paper): he touches so many areas of specialization (chemistry, physics, neurology, evolution), that any typical scientist is bound to understand some parts and completely misunderstand others. I hope his theories are part of what is making biology so exciting lately, people from domains of science that used to be kept separate coming together to figure out amazing stuff. Look at what has happened to evo-devo. There is a rational basis for my hope, he got tired of trying to get his stuff published and recognized, and founded a start-up, flexitral. Applying his own theories, he was able to develop quite a few odorants, some of which have been tested and are commercially available. As the saying goes, the proof of the non-allergenic coumarin replacement is in the smell of newly-mown hay.

By: PeterMcDermott

PeterMcDermott — Wed, 12 Nov 2008 01:19:16 -0800

Absolutely read Emperor of Scent about Luca Turin. OK, *that* was the last thing I bought after a recommendation on Metafilter. I'm in no position to evaluate the science, but the story was fantastic.

By: carter

carter — Wed, 12 Nov 2008 05:41:43 -0800

Thanks for this! I bought and read EOS after the last MeFi post, it was fascinating.

By: Restless Day

Restless Day — Wed, 12 Nov 2008 06:20:06 -0800

*yawn* Another highly-entertaining TED Talk. Another great post from louche mustachio. What I find fascinating is how the olfactory bulb sits in such close proximity to the limbic system, the centers of memory and emotion, in the brain, and how scents can trigger memories and emotions. Also the thing about pheromones. Also how you can trigger a sneeze by looking at the sun. I was at one point a student in a Surgical Technologist program, and one day I was assisting a surgeon who, during the operation said she had to sneeze, and she looked up at the bright overhead light, hoping for a sneezy release. I said I'd heard that there are photo-sensitive nerves in the nose which are responsible for the phenomenon, and I suggested that because she was wearing a surgical mask, looking up at the light might not work. She didn't say anything for a really long time, but finally said, "I've never heard of photo-sensitive nerves in the nose. It can't be true." Nevertheless she did not sneeze. You guys are probably familiar with the Black Phoenix Alchemy Lab, I only recently learned of it via the author Ekaterina Sedia's blog, and as long as we're talking about books here, I really enjoyed Sedia's two novels--

By: PeterMcDermott

PeterMcDermott — Wed, 12 Nov 2008 06:35:50 -0800

Damn, it's no wonder people want to spam us, is it? It sounds like that last post on Turin sent sales of EOS soaring.

By: wenestvedt

wenestvedt — Wed, 12 Nov 2008 07:51:15 -0800

Also, interviewed on The Story in May 2007, which I only listened to the night before last: http://thestory.org/archive/the_story_248_The_Secret_of_Scent.mp3/view

By: mbd1mbd1

mbd1mbd1 — Wed, 12 Nov 2008 09:27:23 -0800

Nice post, thanks. I'm going to get the book in my queue now too. I started a job doing olfactory neuroscience a couple of months ago. Sitting on my desk right now are four separate lists of odorants, totaling about 550 organic compounds. We're looking into how the brain processes the sensory input, not how it is originated - so I can't really get into the specifics - but I'm skeptical that we can measure and respond to quantum effects. It will take a lot of work to overturn the shape theory, or even to expand it to include an understanding of the quantum effects. This is a bigger problem than just how do we smell - the olfactory receptors are the same type as those which bind hormones and neurotransmitters. A complete understanding of how they work would really open up new frontiers in medicine and pharmacology.

By: Dataphage

Dataphage — Wed, 12 Nov 2008 16:43:57 -0800

mbd1mbd1, Do you know if anyone has checked to see if hormones and neurotransmitters have a smell?

By: afflatus

afflatus — Wed, 12 Nov 2008 21:43:56 -0800

mbd1mbd1, I'm curious about your opinion on one of the central critiques that Turin makes of the shape theory. I know you haven't read the book yet, but one of his fundamental arguments of the shape theory is that we would have to have specialized receptors for a truly enormous number of molecules and that there is no evidence of that. The number of different molecules that are picked by the olfactory system is incredibly large and we are able to smell novel molecules that are created artificially. How would you account for that ability in a system that depends on receptors tied to existing shapes? I certainly agree that Turin's hypothesis is by no means proven, but it does satisfy an essential set of criteria that I feel the shape theory fails at: it requires a small number of structures, it a general purpose mechanism and it allows for the recognition of novel inputs. None of the neuroscientists I've hung out with do olfactory work though, so I'm keen to get opinions from others with more grounding in the area.

By: mbd1mbd1

mbd1mbd1 — Thu, 13 Nov 2008 06:59:25 -0800

Well, the working assumption is that we discern odors based on their functional groups, so perhaps the receptors are binding to certain parts of the odor molecule instead of the exact shape of the whole molecule. In fact, people are working to decode all the combinations of receptors that react to a single odor. So a novel odor is just the sum of its parts. I don't know of anyone who has tested the response to hormones or neurotransmitters.

By: afflatus

afflatus — Thu, 13 Nov 2008 09:57:06 -0800

mbd1mbd1, send me a mefi mail when you get done reading the book, I'm genuinely curious about your take on it. Of course the book is 12 years old now (and a Nobel prize awarded for the theory that Turin takes to task). Still, I haven't seen anything that shows why acetophenones smell so different from one another when their shapes are almost identical, yet hydrogen cyanide and benzaldehyde are structured very differently yet smell the same. (Both are examples from his book, btw). Entirely possible that there has been work from the shape-theory camp in the intervening years that has addressed his criticisms and I just haven't seen it. "Mainstream theory addresses concerns of critics" isn't something that tends to get a lot of press, so I may have missed it. Anyway, fascinating stuff all around and I would love to learn more.

By: kisch mokusch

kisch mokusch — Thu, 13 Nov 2008 11:40:53 -0800

but one of his fundamental arguments of the shape theory is that we would have to have specialized receptors for a truly enormous number of molecules and that there is no evidence of that. I have no expertise in this field, but I do know that we have only a limited number of light receptors types in our eyes, and yet we can perceive an enormous variety of colours. As much as I'm intrigued by this theory, I don't think the old one can be dismissed on these grounds.

By: afflatus

afflatus — Sun, 16 Nov 2008 12:40:53 -0800

Kisch Mokusch, the thing there is that the receptors in our eyes do not work by shape. They get excited by certain wavelengths/energies of the incoming light. That is actually what Turin proposes for olfactory receptors...recognition by detection of vibration.