New Research: Smell Can Improve Brain Function With Fabrice Croisé and Dr. Michael Leon

Today we have Phd professor and researcher Michael Leon on the show alongside perfume entrepreneur and founder of Scents of Wood, Fabrice Croisé. In July, Prof Leon published a study which identified a link between olfactory stimulation and memory improvement. The memories of participants in the enriched group improved by 226%. Michael also discusses how regular exposure to varied scents (think 40 per day) can actually combat the effects of dementia. Join us to learn about this fascinating connection and what you can do to take advantage of this new knowledge. 

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Key Moments
“We gave humans different odors on a regular basis and, over the course of six months, they too had a massive improvement in their memory, 226% better than a similar group of older adults who didn’t get this kind of olfactory enrichment.”

“When you look at sommeliers and perfumers, the memory parts of their brains have expanded significantly. So it’s not just that they’re experiencing a nice odor, it’s that it’s actually changing the memory centers of their brain.”

“I’m fascinated. I mean, I’ve never, of the many, many, many things that I’ve heard about smelling and fragrances and scent over the past 30 years of my career, I’ve never heard this. And it’s obviously not the angle that we usually take when we create a fragrance, but it is incredibly fascinating.”

Get in touch with Dr. Michael Leon:
Memory Air
mleon@uci.edu
Michael’s Study

Get in Touch with Fabrice Croisé
Scents of Wood
Instagram

Transcript

Hey, michael, how are you today? Great, how are you? I’m wonderful. And where do we find you today?

Dr. Michael Leon: 7:55

In San Juan Capistrano. It’s equidistant between Los Angeles and San Diego.

David: 8:01

Oh, I know that town. It’s beautiful. Good for you. And today, since we’re gonna be talking about smell and olfactory, we have another kind of smell expert on in expert in fragrance we have Fabrice Quasay. Welcome, fabrice. Hello, how are you? I’m great. Fabrice is the founder of Scent of Wood. Fabrice has decades of experience in the fragrance industry and knows more about smell than I will ever forget, so we’re gonna count on him to help us with part of this discussion.

Fabrice Croisé: 8:31

Taking into consideration that I come from the angle of the art of olfaction rather than the science of olfaction?

David: 8:38

Exactly, yeah, exactly right, because we have two different angles here on the word smell is just a bad word and olfactory is too big of a word and fragrance is sort of a different, I don’t know. Scent is good, we’re gonna go with scent. So, michael, I want to talk a little bit about your background. My understanding is your original interest was your ongoing interest is autism, alzheimer’s, things like this. Is that where you started?

Dr. Michael Leon: 9:02

Well, I started doing basic research and I did that for many, many years, and the basic research really led to what’s called translation of the research into therapies for people. The first way that we did this was we took in our own work on keeping lab animals either in a standard box cage, isolated, or putting them in what’s called an enriched environment, which is a much bigger cage with more friends and more things to do and more things to see, more novelty in their lives. It turns out that taking them from a restricted sensory-motor experience to one where they get significantly more of that makes their brain much, much better. They’re more capable in pretty much every way that you can imagine, and you can see this in humans as well.

David: 9:48

Let’s get to scent. So how did you get into that?

Dr. Michael Leon: 9:53

So it turned out that there was another study showing that you could replicate the entire enriched environment phenomenon in mice, in older mice, just with multiple odors, every day olfactory enrichment, and when you do this, the older mice, the memories improved and they began making more neurons than they had before.

David: 10:15

Wait, I want to stop you there. You’re saying that the only change there was the odor environment and that happened. That was the only change. That was it.

Dr. Michael Leon: 10:23

Different kinds of odors on a regular basis. So that’s pretty powerful, and we thought that maybe we could do the same thing with human and older adults. And that’s exactly what we did. We gave humans different odors on a regular basis, and over the course of six months, they too had a massive improvement in their memory 226% better than a similar group of older adults who didn’t get this kind of olfactory enrichment.

David: 10:50

I want to get to the test in a moment. So my friend Fabrice here, who smells different things, complex things, this is his job all day long. Do we expect Fabrice will never have Alzheimer’s and have tremendous cognitive? This is why he’s so much smarter than me, right? Because he smells things all day long.

Dr. Michael Leon: 11:06

Well, it turns out that they’ve done studies both on master perfumers which I assume Fabrice is one of those and with sommeliers in training, so professional wine tasters actually professional wine smellers and professional perfume smellers. The way that they train is that they sniff dozens of odors every day for months and months, and this is so that they can identify, in the case of sommeliers, the scents that come out of fine wine. And for perfumers, it allows them to put different perfumes together. So it’s in a pleasant aroma for people, for perfumes. And when you look at their brains, the memory parts of their brains have expanded significantly. So it’s not just that they’re experiencing a nice odor, it’s that it’s actually changing the memory centers of their brain.

Fabrice Croisé: 12:00

Okay, and how does that impact the rest of their functioning or their behavior in society.

Dr. Michael Leon: 12:06

So we don’t really know, because people have just looked at their brains. We don’t really know much about if they’re smarter. Of course, when you’re dealing with sommeliers, they’re also drinking large amounts of alcohol, and so that might compensate for the fact that their memory centers are getting better. For perfumers perfumers are amazing to me because they’re sort of like people who write symphonies for orchestras. They have to put together dozens of different smells and know what each smell is going to be like and how it’s going to combine with others. It’s just like putting music together. To me, that’s proof enough of their remarkable ability, and my guess is that we would see similar kinds of things in sommeliers and other people who are using odors on a regular basis, so that they are very much attuned to olfactory stimulation.

David: 13:04

And the part of the brain that we’re talking about here. We’re talking about memory center or we’re talking executive function, any other parts of the brain there’s this, particularly the memory function.

Dr. Michael Leon: 13:12

The memory functions looks like it is most effective, and the reason is that all of the other senses can affect the health of the memory centers of the brain, but they have to go through what’s called a thalamus, which is sort of the back of the brain that monitors and mediates all the other senses. These are the side streets of the brain and so they have much less interaction with the memory centers of the brain, whereas the olfactory system has the only direct superhighway that goes directly into those memory centers and consequently has much more impact on their health. And if you don’t get enough olfactory stimulation over the course of your life, the memory centers actually begin to deteriorate. You can lose olfaction for any of a dozen reasons Toxicity, air pollution, chronically stuffed nose, chronic stress and childhood menopause, head injury. All of those things will further decrease the amount of olfactory stimulation that we’re getting. And in our modern affluent world we just don’t have much olfactory stimulation to begin with. I guess if you took a deep breath now you wouldn’t smell anything.

Fabrice Croisé: 14:26

And Michael, I’m not a perfumer or master perfumer. I’m a brand creator, so I work with master perfumers in order to create the fragrances that we put out in the market, but, just like them, I spend my entire day smelling things. So I’m extremely interested by what you’re describing right now. Have you made the difference in the way you administered fragrances to your patients or to your subjects of the research? Have you made the difference between what we call air care, which is basically candles and sticks and devices that will send the environment around you, versus fragrances, which is what you wear on yourself and your clothes? And, more directly, have you made a difference like that?

Dr. Michael Leon: 15:14

Yes, so we’ve actually formed a company and we’ve produced a device that sits on your nightstand and gives you this kind of stimulation as you sleep. Portiodas twice a night, twice a day, has been shown to improve memory, even in demented older adults, which nobody’s really been able to do thus far. As we speak, olfactory enrichment looks like it is the most effective treatment for dementia.

David: 15:38

You know, I don’t know if this is true. You can tell me? If it’s true, smoke alarms exist because our sense of smell doesn’t happen when we sleep, or, I guess, during certain cycles of sleep. Is that true? So?

Dr. Michael Leon: 15:51

because all of the other senses go through the thalamus. The thalamus has connections to the sleep centers of your brain, so if you have a loud noise or touch somebody or put bright lights on them, they’re going to wake up. People have not been able to wake people up with olfactory stimulation, and that’s because the olfactory sense doesn’t go through the thalamus and so it doesn’t have a connection to the sleep centers of the brain. And people have actually tried to make alarm clocks based on odors, because people who are deaf, of course, can’t hear the fire alarm, and so they would like to have a way of doing this with odors. They even tried frying bacon, and none of that will wake people up. So giving them, giving odors to people as they sleep, allows them to process it and change their brain, but it does not wake them up, which has benefits on both ends.

David: 16:50

Is there a? I guess where I’m going with this? Is there a circadian component to this At night? Does this work better At night? During REM, we’re flushing out our brains, we’re moving our memories from short term to long term. Is that why you’re doing it at night, or does it matter?

Dr. Michael Leon: 17:05

We’re doing it at night because we want to get universal compliance. Oh, I see. Okay, right, With our memory or device you put in a cartridge, press a button just as you’re about to go to sleep and after that you don’t have to do anything. For the next month it automatically goes on a while after you started sleeping and it goes through the whole business without having to do anything. So if you give people the opportunity to do something, people know that it’s a really good idea to do exercise, and very few older adults are doing that, Whereas here everybody can do this because it doesn’t take any effort.

Fabrice Croisé: 17:42

What are the 20 smells that you’ve selected and in which order do you diffuse them? Do you go like you have, like five woody smells, five floors, five fresh and odd? Do you alternate between the various kinds of smells? How did you orchestrate that?

Dr. Michael Leon: 18:03

We try to get a good selection of odors from all of the family groups of odors and we try to mix them so it’s not just woody, woody, woody, but the main reason why we’ve selected these 40 odorances that they’ve been used to improve the memory of older adults who have dementia.

Fabrice Croisé: 18:25

So so do you have? Is there like an old time record smell that is best to to to to improve memory, and is that one that you, that you, have been using and identifying as the best one?

Dr. Michael Leon: 18:39

So many people think along these lines because they’re so accustomed to the idea of aromatherapy. Aromatherapy is when you have a single odor that you think has special characteristics and you give people that odor to treat this or that. Ophanitary enrichment is different in that it really doesn’t matter which odors you use. The important thing is having multiple odors, and so we just selected them because they’re pleasant. Nobody wants unpleasant odors in their bedroom, and it’s the idea that any individual odor isn’t critical. It’s the multiplicity of odors that’s the critical aspect here. There’s very different way people think about odors. They’re really accustomed to thinking of this odor is good for this, this odor is good for that, and we don’t deal with any of that. It’s the more odors it looks like, the better.

David: 19:37

For breeze deals with the complexity of odor, the complexity of scent, I want to say and in the test that I read they’re all sort of single note, essential oils Does the complexity of scent further stimulate the brain?

Dr. Michael Leon: 19:52

It turns out that if you give mixtures of odors, the brain just regards them as a single odor. It’s important to have the odors be discreet and numerous and try to get away from mixing them so that you have basically a soup stimulating the brain. You want individual odors that are enriching the novelty that you experience over the course of the day.

Fabrice Croisé: 20:19

If I understand you well, then it’s more the alternance and the variety and the contrast between smells that matters, rather than the composition and the nature of the smells that we smell.

Dr. Michael Leon: 20:32

Exactly.

Fabrice Croisé: 20:33

I see.

David: 20:36

What’s the optimal cycling on this?

Dr. Michael Leon: 20:39

We don’t know the optimal cycling, but I’m blowing to have a 226% improvement in memory in older adults and to improve memory in older adults with dementia by up to 300%. So there may be an even better way of doing this. Maybe more odors, maybe more times a day, maybe different odors, we don’t know. But if we just stick to what we know, it’s pretty remarkable.

David: 21:11

There’s something here I read about olfactory stimulation during sleep, deep in slow wave sleep. There’s a study cited here the most restful portion of the sleep cycle and people report feeling more vigorous the next day after nighttime. Olfactory exposure olderness enhanced normal sleep and they also improve abnormal sleep at a magnitude similar to that of sleep medication. So what I understand here is that if we’re being sent stimulated at night, we’re going to sleep better. Is that you think that right?

Dr. Michael Leon: 21:40

Yeah, that’s the bonus. So in addition to having universal compliance, you get to have a better night’s sleep. That’s the cherry on top.

David: 21:50

I want to get to the cognition test. Forgive me, here, I’m not a scientist, so help me out. What was the cognition test? Let’s go back a little bit. How many people were in the study? 43., 43. And then you split between a control and a test group.

Dr. Michael Leon: 22:08

People were randomly assigned to either getting olfactory enrichment or to getting everything else.

David: 22:14

They had all the device and all the things going but no odor was coming out. And it went on for six months, Once in the beginning and then after six months.

Dr. Michael Leon: 22:22

Right Once at the beginning, before they started, and then after six months, after they’ve had either at olfactory enrichment for six months or not olfactory enrichment for six months.

David: 22:32

What’s a cognition test? Help me out. What is that?

Dr. Michael Leon: 22:35

Well, this is a very simple one, but it’s been used many, many times and it’s very reliable and it’s been shown to be valid. That is, if you look a number of these tests, they have the same kind of output and all it is is you have somebody carefully recite a list of words 15 words and you ask people to remember that, and then you ask them again. You read them again. They ask they do it again, and you do it five times and then you have a delay and then you do it a sixth time. And what this does is it shows how people can start to remember words and words are just one way of assessing memory but it shows a very dramatic improvement after the six months of stimulation.

David: 23:26

So each group has five of these they go through. And then were you seeing similar up through the gradation of the five, or no, we just looked at the fifth time they were given this list Just the fifth.

Dr. Michael Leon: 23:40

And that shows that they’ve been improving their ability to learn things and their ability to remember things, and it turns out that that was sufficient to show a dramatic improvement.

David: 23:53

I’m just curious why five and not one.

Dr. Michael Leon: 23:56

Because you get better right. If I gave you a list of things, you would get maybe three or four right, but with repetition you might get nine out of the 15, right, and so this shows, if you keep on just having three right, that you’re not learning and remembering very well. If, on the other hand, you get 10 right out of 15, it shows that you’ve improved quite clearly.

David: 24:25

So, michael, I want to give you a scenario here. I’m going to plug for Breeze’s company, because it’s awesome. They do a subscription thing right. So you get like one every month. So now I have a lot of them. I don’t know, I’ve got like 12 or 15. So now, if I wear a different fragrance, a different scent every day, so I’m stimulating myself every day, is that helping my brain or do I need to change it faster?

Dr. Michael Leon: 24:51

Yeah, probably that’s just one other way of doing it and I assume that these odors are pretty different from each other and over time you would get different kinds of odor stimulation, stimulating the memory centers of your brain, and you should have improvement.

David: 25:10

What do you think Fabrice?

Fabrice Croisé: 25:11

I’m fascinated. I mean I’ve never, of the many, many, many things that I’ve heard about about smelling and fragrances and scent over the past 30 years of my career, I’ve never heard this and it’s obviously not the angle that we usually take when we create a fragrance, but it seemed incredibly fascinating. Michael, do you find there’s a difference with words like poetry or music or like? Do you think that listening to different type, contrasting types of music, whether it’s during your sleep or during waking hours, do you think that would help as well? Or is it something that you have established is specific to the smelling sense?

Dr. Michael Leon: 25:56

So all kinds of stimulation are good for the memory centers of your brain. Hearing certainly is important. If you don’t get enough auditory stimulation, the memory centers of your brain start to go south, and that’s why it’s important for older adults to get hearing aids when they need them, and particularly men, because men are five times more likely to need a hearing aid, but they’re much less likely to actually get them, and that’s partly due to the cost, which can be thousands of dollars. But it’s also because they don’t want to appear to be old. But because they don’t want to appear to be old, that will further cause their memory centers to deteriorate and they will actually get older. So definitely they should do that. Vision is also something that needs to be maintained. For example, if your lenses start to cloud over, you want to get them replaced, because in those cases your memory centers will deteriorate along with your memory. It’s also true of chewing. So chewing is also something that stimulates the memory centers of your brain. And if you don’t get enough chewing, let’s say you go on a liquid diet, which people do because it’s easier, particularly as they get older that also causes the memory centers of their brain to deteriorate. Similarly, people who aren’t exercising same thing.

Fabrice Croisé: 27:25

What I find particularly, particularly fascinating in what you’re telling us today is that it’s the opposite looking at. It’s looking at smell in a complete opposite way of the way I’ve been trying to do, which is that what you actually smell doesn’t matter. What matters is that there is a rhythm, a contrast, a variety, that you smell something new. You said that you focus on pleasant smells because no one wants to have bad smells in their home, but I would assume that if you did it with bad smells, it would be the same, as long as you keep contrasting and you keep that rhythm there. So it doesn’t matter what it smells like. What matters is that it smells like something, and it changes all the time, and I find that extremely interesting.

Dr. Michael Leon: 28:10

One possibility for marketing perfumes is to put a kit together with a dozen different perfumes and tell people it not only will be pleasant to them, but it will also help their brain.

Fabrice Croisé: 28:23

I work with a company that specializes in air care and they have developed. It’s based here in the city named Pura, and they developed cartridges that you plug to the wall and their current system allows for two cartridges and you have an app that you can direct the device with and you can have one smell in your room for, let’s say, 1pm or 2pm, and then it uses the other smell, and so on. They should talk to people like you or to you as a person, because they should have more than two smells in their devices. They should alternate them often and if they can have a therapeutic impact on their customers I mean, there might be something like I’m looking at it from a business perspective, but from a health perspective of a combination of both could be extraordinary.

Dr. Michael Leon: 29:14

People have always been drawn to pleasant odors, so the reason that pretty much everything every consumer product you buy is scented is that people tend not to buy them unless they are scented. So people are really motivated to get odors, and my guess is that evolution has made it so that we are drawn to odors. We just didn’t know what the optimum would be for smelling odors. That is, we didn’t know that what you really need is not one odor or two odors, but multiple odors every day, and that is probably why we’re drawn to odors. So much is that our brain really needs them.

Fabrice Croisé: 29:58

Could we envision some kind of a research that contrasts a group of people who have smelled heavily for a living, whose life has entirely been dedicated to smelling new things all the time, on one hand, and people who, on the other hand, have smelled only the same thing their entire life, Like they’ve worked in the same factory and they’ve smelled the same smell of rubber the entire, or whatever it might be right and then see if there’s a difference in the way they age and in the way they keep or don’t keep their memory or are subject or not subject to diseases like Alzheimer? Is that something that has been done or that could be done or that you think could be?

Dr. Michael Leon: 30:37

done. This idea is relatively new, and so people haven’t done these long term studies, which is what you’d need years and years of monitoring people. Yes, it absolutely could be done, and in fact, you can predict which older adults are most likely to develop mild cognitive impairment the first step on the road to dementia. And among people with mild cognitive impairment, you can predict which ones are most likely to develop Alzheimer’s disease. And among the people who develop Alzheimer’s disease, you can predict which ones are most likely to develop a rapid decline in their memory, all by their ability to smell things and, in fact, by your middle age. There are now seven large epidemiological studies showing that you’re all caused. Mortality that is, whether you live or whether you die for any reason can be predicted by your ability to smell things.

David: 31:35

I’ve had Dr Mike Royzen on here a couple of times. Mike’s the head of wellness for the Cleveland Clinic and one of his protocols is every day and I remember he told me this. I had no idea what he was talking about. He’s like you need to smell four powerful things every day and I think he told me like he rattled them off, like you need to smell garlic, you need to smell this, and that he was looking at it. My understanding was as a test that you might have some future cognitive issue, but actually from what I’m learning from you is it’s preventative Right.

Dr. Michael Leon: 32:06

So it’s. People have talked about using smelling tests to see if you are vulnerable to Alzheimer’s disease, parkinson’s disease, depression, all of these things. The loss of all faction comes well before any other symptom. So the loss of all faction is the first thing to go south in Alzheimer’s disease, same thing with Parkinson’s, same thing with depression. And there are actually about 70 different neurological disorders that are accompanied by olfactory loss. So all the ones you know of anorexia, autism, depression, epilepsy, stroke all of them are associated with olfactory loss. And the things that are most likely to kill you heart disease, cancer, liver disease, lung disease, kidney disease all of those are accompanied by olfactory loss. So it may be that the loss of all faction makes you vulnerable to expressing the symptoms of these disorders. So with the children with autism, for example, they still have autism, but they don’t express the symptoms. And you can see this with Alzheimer’s disease as well. There’s something called a cognitive reserve, which means that people who actually have all the neuropathology, that is, all the damage in their brain. So you look at that and you say, oh, this person is really far gone. And it turns out that they don’t have any memory loss and the reason is is that they have built up their cognitive ability over their lifetime so that they are highly educated, highly sociable, have careers that are demanding intellectually. And it builds up a cognitive reserve so that you can have Alzheimer’s disease but not have the symptoms of memory loss. And we think what olfactory stimulation is doing is it serves as an olfactory reserve that can take the place of cognitive reserve, so you don’t have to go back and get into PhD, you can just get olfactory stimulation at any age. We talk a lot here about extra cognitive loss.

David: 34:23

We talk a lot here about exercise, all the time. We talk about exercise. All the time we talk. You know all these different ways to reduce all cause mortality. I love that expression, by the way. All cause, this is my favorite expression. So if we were to say, suggest a program to people, we want you to live longer and healthier and stuff, so I would you know, I’d say OK, like what are you eating, how are you exercising, how are you? Let’s talk about your sleep. And if I went to you and I said, ok, we want to put this other layer of difference in here, as you were saying, you know, sort of an olfactory reserve, what would you be suggesting people to do?

Dr. Michael Leon: 35:01

I would say, if you can get 40 odors twice a night, you should do it. If you can do it during the day.

David: 35:07

Forty different odors a day that’s, that’s a lot, it sounds like a lot, but it’s actually not so much.

Dr. Michael Leon: 35:13

I’ve been doing it for years and I actually use a summer year training kit and it just has a bunch of odors that are lined up Well, while I’m watching television I just go like that Take the next one.

David: 35:26

Oh, that’s all. It’s just like a moment, right yeah.

Dr. Michael Leon: 35:29

It’s. It’s not the overwhelming stimulation, it’s the multiplicity of stimuli.

David: 35:35

So if I’m in the grocery store, smell everything, people are going to think I’m a nut. I want to smell this, I want to smell this, I want to smell this, I want to smell this, just constantly smell, you know, like the way it’ll just take you 10 or 15 minutes to do it at home.

Dr. Michael Leon: 35:47

Oh OK, oh OK.

Fabrice Croisé: 35:50

Fabrice what are your thoughts on this? Well, my thought, my first thought, is that this is pretty much the way I live, because I’m I am just just out of sheer luck Right Now. I’m learning that I’m going to keep my memory for a long time, but I am constantly smelling different versions of the same smell, or contrasting a smell with another to see if they fit well within my brand, or smelling ingredients that compose a smell to understand the role that each of them plays. So I live my life, and you know that, david, I live my life with blotters all the time. I have blotters in my pockets, I have blotters in my house, I’ve blotters, and you know. So that what would you, what you do in front of your TV for 15 minutes or 20 minutes at night? I do it for a living all day long. So that’s, I guess this conversation is great news for my future health. I agree with you that it takes very little organization and time to actually make that happen. All you have to do is I mean, you do it with a sommelier kit, you can do it with a perfumer kit, you can do it with a final, final fragrances Right, you could, you can have like your collection of fragrances that you love. You put them on your blotters and you just smell them for a while, almost absent mindedly, and then you go to the next one, right? That’s this is incredible. Have you? Have you published your research?

Dr. Michael Leon: 37:12

We have and the people are really fascinated by it. So in the month that it’s been out, there have been over 220,000 people who’ve read the article, which is amazing. That typically doesn’t happen. There also have been 145 news stories about us and people tweeting and all sorts of stuff. So people are really fascinated by it. Seems to have hit a nerve.

Fabrice Croisé: 37:43

The olfactory nerve. Yes, this is amazing. Well, I’m so glad that that was part of this conversation. David, this is really quite extraordinary what I’m listening to when I’m hearing here. This is really quite wonderful. As a matter of fact, michael, I would love to have you on my Instagram just so that you tell the story that you just told to people who are interested in fragrance specifically in fragrance, because a brand like mine and many other brands our core customer is not somebody who buys a fragrance once in a while, but it’s people like David who have a genuine love for fragrance and collect them and have somewhere between 10 and 350 fragrances at home and it sounds like a crazy amount, but there’s a lot of people who have more than 100 fragrances at home. And brand like mine cares to those people, and I’m sure that listening to you would make them feel very happy, like I’m feeling right now, about their future prospects, because they’ve been doing something extremely good for their health without never knowing it.

Dr. Michael Leon: 38:50

Well, my guess is that there’s something that they’re drawn to it and they don’t know why. And my guess is that there’s an evolutionary reason, that people are drawn to these odors because their brain really needs them. And people who sniffed odors a lot had much more success than people who didn’t, and I’m sure you know this. But there are people who really don’t like any odors. There are people who like many, many different odors and they like a lot of them. And then there are the people in the middle mostly, who like odors because you can’t get a shampoo that isn’t scented, for example.

Fabrice Croisé: 39:30

But there’s something, there’s an implication to what you have discovered which I think is extremely fascinating, which is that smell remains the unsung hero of the senses right, and for 10 different music or for 200 different pieces of music that you will hear in your life, you will smell two fragrances. Right Now you do smell the garlic and you do smell the tomato and you smell that, but it’s not something that you necessarily focus on. For, like for 100 movies that you will watch or 100 pictures that you will take and look at, there will be like one scent right, and what I hear you say is that if we rebalanced our sensory experience of life a little bit better or even more towards the affective, the world of the affective, you would have positive implications on our health, and that’s amazing. That is incredible.

Dr. Michael Leon: 40:26

I should also point out that it also helps emotionally. So, in addition to improving the memory of older adults with dementia, it also decreased their depression symptoms by 325%, which is just extraordinary. It also helps people who have PTSD. If you give them olfactory stimulation while they’re sleeping, they tend not to have the nightmares that wake them up and make their lives miserable, and so we think there’s also an important emotional aspect to it, and again, because the olfactory input has a direct input into the emotional center of the brain, as opposed to all the others that don’t go directly there.

Fabrice Croisé: 41:14

A lot of what you’re saying reminds me of what I hear about scientists and doctors who are involved with hallucinogenic drugs and using them to treat PTSD and to treat depression and to treat which is a very new field in medicine, and that’s very interesting. Well, I’m so fascinated by this conversation. Thank you so much. It’s an amazing, amazing conversation, David. I’m so thankful again for your ideas and your connections.

David: 41:54

It’s great to have you on for Breeze, michael. We’re going to leave a link to the paper in our show notes. Fascinating, there has been some press out there, sort of slamming this.

Dr. Michael Leon: 42:03

Yeah, anything you do these days.

David: 42:08

Anything you and yeah.

Dr. Michael Leon: 42:11

So it would also be helpful because otherwise people will contact me if you could put up a memory aircom connection because people will want to sign up for it. We’ll let them know when it’s available for them.

David: 42:23

Michael, it’s been a pleasure. I’m already sensing after you get off the call I’m going to contact my friend for Breeze and say I need another dozen candles. Get them over here. Okay.

Dr. Michael Leon: 42:34

You’re free.

David: 42:35

David. All right, take care, michael. Thank you so much for your time.