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  • Translator: Ivana Korom Reviewer: Krystian Aparta

  • So I had this very interesting experience

  • five years ago.

  • You know, me and my husband, we were out grocery shopping,

  • as we do every other day,

  • but this time, we found this fancy,

  • you know, I'm talking fair-trade, I'm talking organic,

  • I'm talking Kenyan, single-origin coffee

  • that we splurged and got.

  • And that was when the problem started already.

  • You know, my husband, he deemed this coffee blend superior

  • to our regular and much cheaper coffee,

  • which made me imagine a life based solely on fancy coffee

  • and I saw our household budget explode.

  • (Laughter)

  • And worse ...

  • I also feared that this investment would be in vain.

  • That we wouldn't be able to notice this difference after all.

  • Unfortunately, especially for my husband,

  • he had momentarily forgotten that he's married to a neuroscientist

  • with a specialty in food science.

  • (Laughter)

  • Alright?

  • So without further ado,

  • I mean, I just put him to the test.

  • I set up an experiment

  • where I first blindfolded my husband.

  • (Laughter)

  • Then I brewed the two types of coffee

  • and I told him that I would serve them to him

  • one at a time.

  • Now, with clear certainty,

  • my husband, he described the first cup of coffee

  • as more raw and bitter.

  • You know, a coffee that would be ideal for the mornings

  • with the sole purpose of terrorizing the body awake by its alarming taste.

  • (Laughter)

  • The second cup of coffee, on the other hand,

  • was both fruity and delightful.

  • You know, coffee that one can enjoy in the evening and relax.

  • Little did my husband know, however,

  • that I hadn't actually given him the two types of coffee.

  • I had given him the exact same cup of coffee twice.

  • (Laughter)

  • And obviously, it wasn't this one cup of coffee

  • that had suddenly gone from horrible to fantastic.

  • No, this taste difference was a product of my husband's own mind.

  • Of his bias in favor of the fancy coffee

  • that made him experience taste differences that just weren't there.

  • Alright, so, having saved our household budget,

  • and finishing on a very good laugh,

  • me especially --

  • (Laughter)

  • I then started wondering just how we could have received

  • two such different responses from a single cup of coffee.

  • Why would my husband make such a bold statement

  • at the risk of being publicly mocked for the rest of his life?

  • (Laughter)

  • The striking answer is that I think you would have done the same.

  • And that's the biggest challenge in my field of science,

  • assessing what's reality behind these answers

  • that we receive.

  • Because how are we going to make food tastier

  • if we cannot rely on what people actually say they like?

  • To understand, let's first have a look at how we actually sense food.

  • When I drink a cup of coffee,

  • I detect this cup of coffee by receptors on my body,

  • information which is then turned into activated neurons in my brain.

  • Wavelengths of light are converted to colors.

  • Molecules in the liquid are detected by receptors in my mouth,

  • and categorized as one of five basic tastes.

  • That's salty, sour, bitter, sweet and umami.

  • Molecules in the air are detected by receptors in my nose

  • and converted to odors.

  • And ditto for touch, for temperature, for sound and more.

  • All this information is detected by my receptors

  • and converted into signals between neurons in my brain.

  • Information which is then woven together and integrated,

  • so that my brain recognizes

  • that yes, I just had a cup of coffee, and yes, I liked it.

  • And only then,

  • after all this neuron heavy lifting,

  • do we consciously experience this cup of coffee.

  • And this is now where we have a very common misconception.

  • People tend to think that what we experience consciously

  • must then be an absolute true reflection of reality.

  • But as you just heard,

  • there are many stages of neural interpretation

  • in between the physical item and the conscious experience of it.

  • Which means that sometimes,

  • this conscious experience is not really reflecting that reality at all.

  • Like what happened to my husband.

  • That's because some physical stimuli may just be so weak

  • that they just can't break that barrier to enter our conscious mind,

  • while the information that does

  • may get twisted on its way there by our hidden biases.

  • And people, they have a lot of biases.

  • Yes, if you're sitting there right now, thinking ...

  • you could probably have done better than my husband,

  • you could probably have assessed those coffees correctly,

  • then you're actually suffering from a bias.

  • A bias called the bias blind spot.

  • Our tendency to see ourselves as less biased than other people.

  • (Laughter)

  • And yeah, we can even be biased

  • about the biases that we're biased about.

  • (Laughter)

  • Not trying to make this any easier.

  • A bias that we know in the food industry is the courtesy bias.

  • This is a bias where we give an opinion

  • which is considered socially acceptable,

  • but it's certainly not our own opinion, right?

  • And I'm challenged by this as a food researcher,

  • because when people say they like my new sugar-reduced milkshake,

  • do they now?

  • (Laughter)

  • Or are they saying they like it

  • because they know I'm listening and they want to please me?

  • Or maybe they just to seem fit and healthy in my ears.

  • I wouldn't know.

  • But worse, they wouldn't even know themselves.

  • Even trained food assessors,

  • and that's people who have been explicitly taught

  • to disentangle the sense of smell and the sense of taste,

  • may still be biased to evaluate products sweeter

  • if they contain vanilla.

  • Why?

  • Well, it's certainly not because vanilla actually tastes sweet.

  • It's because even these professionals are human,

  • and have eaten lot of desserts, like us,

  • and have therefore learned to associate sweetness and vanilla.

  • So taste and smell and other sensory information

  • is inextricably entangled in our conscious mind.

  • So on one hand, we can actually use this.

  • We can use these conscious experiences,

  • use this data, exploit it by adding vanilla instead of sugar

  • to sweeten our products.

  • But on the other hand,

  • with these conscious evaluations,

  • I still wouldn't know

  • whether people actually liked that sugar-reduced milkshake.

  • So how do we get around this problem?

  • How do we actually assess what's reality

  • behind these conscious food evaluations?

  • The key is to remove the barrier of the conscious mind

  • and instead target the information in the brain directly.

  • And it turns out

  • our brain holds a lot of fascinating secrets.

  • Our brain constantly receives sensory information from our entire body,

  • most of which we don't even become aware of,

  • like the taste information that I constantly receive

  • from my gastrointestinal tract.

  • And my brain will also act on all this sensory information.

  • It will alter my behavior without my knowledge,

  • and it can increase the diameter of my pupils

  • if I experience something I really like.

  • And increase my sweat production ever so slightly

  • if that emotion was intense.

  • And with brain scans,

  • we can now assess this information in the brain.

  • Specifically, I have used a brain-scanning technique

  • called electroencephalography,

  • or "EEG" in short,

  • which involves wearing a cap studded with electrodes,

  • 128 in my case.

  • Each electrode then measures the electrical activity of the brain

  • with precision down to the millisecond.

  • The problem is, however,

  • it's not just the brain that's electrically active,

  • it's also the rest of the body as well as the environment

  • that contains a lot of electrical activity all the time.

  • To do my research,

  • I therefore need to minimize all this noise.

  • So I ask my participants to do a number of things here.

  • First off,

  • I ask them to rest their head in a chin rest,

  • to avoid too much muscle movement.

  • I also ask them to, meanwhile, stare at the center of a computer monitor

  • to avoid too much eye movements and eye blinks.

  • And I can't even have swallowing,

  • so I ask my participants to stick the tongue out of their mouth

  • over a glass bowl,

  • and then I constantly let taste stimuli onto the tongue,

  • which then drip off into this bowl.

  • (Laughter)

  • And then, just to complete this wonderful picture,

  • I also provide my participants with a bib,

  • available in either pink or blue, as they please.

  • (Laughter)

  • Looks like a normal eating experience, right?

  • (Laughter)

  • No, obviously not.

  • And worse,

  • I can't even control what my participants are thinking about,

  • so I need to repeat this taste procedure

  • multiple times.

  • Maybe the first time, they're thinking about the free lunch

  • that I provide for participating,

  • or maybe the second time, they're thinking about Christmas coming up

  • and what to get for Mom this year, you know.

  • But common for each response is the response to the taste.

  • So I repeat this taste procedure multiple times.

  • Sixty, in fact.

  • And then I average the responses,

  • because responses unrelated to taste will average out.

  • And using this method,

  • we and other labs,

  • have investigated how long a time it takes from "food lands on our tongue"

  • until our brain has figured out which taste it's experiencing.

  • Turns out this occurs within the first already 100 milliseconds,

  • that's about half a second before we even become aware of it.

  • And next up, we also investigated

  • the taste difference between sugar and artificial sweeteners

  • that in our setup taste extremely similar.

  • In fact, they tasted so similar

  • that half my participants could only barely tell the taste apart,

  • while the other half simply couldn't.

  • But amazingly,

  • if we looked across the entire group of participants,

  • we saw that their brains definitely could tell the taste apart.

  • So with EEG and other brain-scanning devices

  • and other physiological measures --

  • sweat and pupil size --

  • we have new gateways to our brain.

  • Gateways that will help us remove the barrier of the conscious mind

  • to see through the biases of people

  • and possibly even capture subconscious taste differences.

  • And that's because we can now measure people's very first response to food

  • before they've become conscious of it,

  • and before they've started rationalizing why they like it or not.

  • We can measure people's facial expressions,

  • we can measure where they're looking,

  • we can measure their sweat response,

  • we can measure their brain response.

  • And with all these measures,

  • we are going to be able to create tastier foods,

  • because we can measure whether people actually like

  • that sugar-reduced milkshake.

  • And we can create healthier foods without compromising taste,

  • because we can measure the response to different sweeteners

  • and find the sweetener that gives the response that's more similar

  • to the response from sugar.

  • And furthermore, we can just help create healthier foods,

  • because we can help understand how we actually sense food

  • in the first place.

  • Which we know surprisingly little about.

  • For example, we know that there are those five basic tastes,

  • but we strongly suspect that there are more,

  • and in fact, using our EEG setup, we found evidence that fat,

  • besides being sensed by its texture and smell,

  • is also tasted.

  • Meaning that fat could be this new sixth basic taste.

  • And if we figure out how our brain recognizes fat and sugar,

  • and I'm just dreaming here,

  • but could we then one day