TED@DuPont
Camilla Arndal Andersen: What happens in your brain when you taste food
Filmed:
Readability: 4.5
1,767,675 views
With fascinating research and hilarious anecdotes, neuroscientist Camilla Arndal Andersen takes us into the lab where she studies people's sense of taste via brain scans. She reveals surprising insights about the way our brains subconsciously experience food -- and shows how this data could help us eat healthier without sacrificing taste.
Camilla Arndal Andersen - Neuroscientist
Instead of asking them what they think, Camilla Arndal Andersen covers her subjects in sensors to reveal their unfiltered and subconscious response to food. Full bio
Instead of asking them what they think, Camilla Arndal Andersen covers her subjects in sensors to reveal their unfiltered and subconscious response to food. Full bio
Double-click the English transcript below to play the video.
00:12
So I had this very interesting experience
0
817
3270
00:16
five years ago.
1
4111
1150
00:18
You know, me and my husband,
we were out grocery shopping,
we were out grocery shopping,
2
6278
2825
00:21
as we do every other day,
3
9127
1593
00:22
but this time, we found this fancy,
4
10744
3349
00:26
you know, I'm talking fair-trade,
I'm talking organic,
I'm talking organic,
5
14117
3722
00:29
I'm talking Kenyan, single-origin coffee
6
17863
2532
00:32
that we splurged and got.
7
20419
1733
00:35
And that was when the problem
started already.
started already.
8
23252
3302
00:38
You know, my husband,
he deemed this coffee blend superior
he deemed this coffee blend superior
9
26578
3840
00:42
to our regular and much cheaper coffee,
10
30442
2389
00:44
which made me imagine a life
based solely on fancy coffee
based solely on fancy coffee
11
32855
4349
00:49
and I saw our household budget explode.
12
37228
2428
00:51
(Laughter)
13
39680
1001
00:52
And worse ...
14
40705
1150
00:55
I also feared that this investment
would be in vain.
would be in vain.
15
43038
3102
00:58
That we wouldn't be able to notice
this difference after all.
this difference after all.
16
46164
3516
01:03
Unfortunately, especially for my husband,
17
51355
3833
01:07
he had momentarily forgotten
that he's married to a neuroscientist
that he's married to a neuroscientist
18
55212
3120
01:10
with a specialty in food science.
19
58356
1785
01:12
(Laughter)
20
60165
1174
01:13
Alright?
21
61363
1173
01:14
So without further ado,
22
62560
1627
01:16
I mean, I just put him to the test.
23
64211
2217
01:19
I set up an experiment
24
67126
1961
01:21
where I first blindfolded my husband.
25
69111
2885
01:24
(Laughter)
26
72475
1151
01:25
Then I brewed the two types of coffee
27
73650
3451
01:29
and I told him that
I would serve them to him
I would serve them to him
28
77125
2580
01:31
one at a time.
29
79729
1340
01:34
Now, with clear certainty,
30
82387
1849
01:36
my husband, he described
the first cup of coffee
the first cup of coffee
31
84260
2418
01:38
as more raw and bitter.
32
86702
1296
01:40
You know, a coffee
that would be ideal for the mornings
that would be ideal for the mornings
33
88022
2730
01:42
with the sole purpose of terrorizing
the body awake by its alarming taste.
the body awake by its alarming taste.
34
90776
3971
01:46
(Laughter)
35
94771
2103
01:48
The second cup of coffee,
on the other hand,
on the other hand,
36
96898
2864
01:51
was both fruity and delightful.
37
99786
3791
01:55
You know, coffee that one
can enjoy in the evening and relax.
can enjoy in the evening and relax.
38
103601
4067
02:01
Little did my husband know, however,
39
109466
2833
02:04
that I hadn't actually given him
the two types of coffee.
the two types of coffee.
40
112323
3325
02:07
I had given him the exact same
cup of coffee twice.
cup of coffee twice.
41
115672
3138
02:10
(Laughter)
42
118834
2167
02:13
And obviously, it wasn't
this one cup of coffee
this one cup of coffee
43
121358
2634
02:16
that had suddenly gone
from horrible to fantastic.
from horrible to fantastic.
44
124016
2944
02:19
No, this taste difference
was a product of my husband's own mind.
was a product of my husband's own mind.
45
127270
3867
02:23
Of his bias in favor of the fancy coffee
46
131521
3007
02:26
that made him experience taste differences
that just weren't there.
that just weren't there.
47
134552
3389
02:31
Alright, so, having saved
our household budget,
our household budget,
48
139640
4701
02:36
and finishing on a very good laugh,
49
144365
1683
02:38
me especially --
50
146072
1175
02:39
(Laughter)
51
147271
1007
02:40
I then started wondering
just how we could have received
just how we could have received
52
148302
2966
02:43
two such different responses
from a single cup of coffee.
from a single cup of coffee.
53
151292
3602
02:47
Why would my husband
make such a bold statement
make such a bold statement
54
155331
3691
02:51
at the risk of being publicly mocked
for the rest of his life?
for the rest of his life?
55
159046
4447
02:55
(Laughter)
56
163517
1833
02:58
The striking answer is
that I think you would have done the same.
that I think you would have done the same.
57
166831
4341
03:03
And that's the biggest challenge
in my field of science,
in my field of science,
58
171196
3246
03:06
assessing what's reality
behind these answers
behind these answers
59
174466
3310
03:09
that we receive.
60
177800
1166
03:10
Because how are we
going to make food tastier
going to make food tastier
61
178990
2811
03:13
if we cannot rely on what people
actually say they like?
actually say they like?
62
181825
3594
03:18
To understand, let's first have a look
at how we actually sense food.
at how we actually sense food.
63
186728
3530
03:22
When I drink a cup of coffee,
64
190923
2318
03:25
I detect this cup of coffee
by receptors on my body,
by receptors on my body,
65
193265
4142
03:29
information which is then turned
into activated neurons in my brain.
into activated neurons in my brain.
66
197431
4447
03:34
Wavelengths of light
are converted to colors.
are converted to colors.
67
202570
2730
03:37
Molecules in the liquid
are detected by receptors in my mouth,
are detected by receptors in my mouth,
68
205324
4135
03:41
and categorized as one
of five basic tastes.
of five basic tastes.
69
209483
3321
03:45
That's salty, sour,
bitter, sweet and umami.
bitter, sweet and umami.
70
213266
4230
03:50
Molecules in the air
are detected by receptors in my nose
are detected by receptors in my nose
71
218433
3301
03:53
and converted to odors.
72
221758
1534
03:55
And ditto for touch, for temperature,
for sound and more.
for sound and more.
73
223704
4373
04:00
All this information is detected
by my receptors
by my receptors
74
228394
3858
04:04
and converted into signals
between neurons in my brain.
between neurons in my brain.
75
232276
3269
04:07
Information which is then
woven together and integrated,
woven together and integrated,
76
235569
4887
04:12
so that my brain recognizes
77
240480
2851
04:15
that yes, I just had a cup of coffee,
and yes, I liked it.
and yes, I liked it.
78
243355
5757
04:21
And only then,
79
249763
1976
04:23
after all this neuron heavy lifting,
80
251763
2984
04:26
do we consciously experience
this cup of coffee.
this cup of coffee.
81
254771
3265
04:30
And this is now where we have
a very common misconception.
a very common misconception.
82
258988
3934
04:35
People tend to think
that what we experience consciously
that what we experience consciously
83
263473
3531
04:39
must then be an absolute
true reflection of reality.
true reflection of reality.
84
267028
3190
04:42
But as you just heard,
85
270588
1714
04:44
there are many stages
of neural interpretation
of neural interpretation
86
272326
3516
04:47
in between the physical item
and the conscious experience of it.
and the conscious experience of it.
87
275866
4505
04:52
Which means that sometimes,
88
280395
2119
04:54
this conscious experience is not really
reflecting that reality at all.
reflecting that reality at all.
89
282538
3803
04:58
Like what happened to my husband.
90
286720
2200
05:01
That's because some physical stimuli
may just be so weak
may just be so weak
91
289808
4142
05:05
that they just can't break that barrier
to enter our conscious mind,
to enter our conscious mind,
92
293974
4373
05:10
while the information that does
93
298371
1882
05:12
may get twisted on its way there
by our hidden biases.
by our hidden biases.
94
300277
4086
05:16
And people, they have a lot of biases.
95
304824
4171
05:23
Yes, if you're sitting there
right now, thinking ...
right now, thinking ...
96
311649
2532
05:27
you could probably have done
better than my husband,
better than my husband,
97
315760
3016
05:30
you could probably have assessed
those coffees correctly,
those coffees correctly,
98
318800
3547
05:34
then you're actually
suffering from a bias.
suffering from a bias.
99
322371
2809
05:38
A bias called the bias blind spot.
100
326116
2469
05:40
Our tendency to see ourselves
as less biased than other people.
as less biased than other people.
101
328609
4806
05:45
(Laughter)
102
333717
1190
05:46
And yeah, we can even be biased
103
334931
1493
05:48
about the biases that we're biased about.
104
336448
1967
05:50
(Laughter)
105
338439
1001
05:51
Not trying to make this any easier.
106
339464
2124
05:54
A bias that we know in the food industry
is the courtesy bias.
is the courtesy bias.
107
342270
4626
05:59
This is a bias where we give an opinion
108
347619
2413
06:02
which is considered socially acceptable,
109
350056
3655
06:05
but it's certainly not
our own opinion, right?
our own opinion, right?
110
353735
2665
06:09
And I'm challenged by this
as a food researcher,
as a food researcher,
111
357575
2555
06:12
because when people say they like
my new sugar-reduced milkshake,
my new sugar-reduced milkshake,
112
360154
5098
06:17
do they now?
113
365276
1182
06:18
(Laughter)
114
366482
1055
06:19
Or are they saying they like it
115
367561
2349
06:21
because they know I'm listening
and they want to please me?
and they want to please me?
116
369934
2981
06:25
Or maybe they just to seem
fit and healthy in my ears.
fit and healthy in my ears.
117
373544
3224
06:30
I wouldn't know.
118
378115
1603
06:31
But worse, they wouldn't
even know themselves.
even know themselves.
119
379742
4613
06:37
Even trained food assessors,
120
385348
1357
06:38
and that's people who have been
explicitly taught
explicitly taught
121
386729
2571
06:41
to disentangle the sense of smell
and the sense of taste,
and the sense of taste,
122
389324
4127
06:45
may still be biased
to evaluate products sweeter
to evaluate products sweeter
123
393475
3107
06:48
if they contain vanilla.
124
396606
1533
06:50
Why?
125
398455
1150
06:51
Well, it's certainly not
because vanilla actually tastes sweet.
because vanilla actually tastes sweet.
126
399978
3150
06:56
It's because even these
professionals are human,
professionals are human,
127
404510
3956
07:00
and have eaten lot of desserts, like us,
128
408490
3230
07:03
and have therefore learned to associate
sweetness and vanilla.
sweetness and vanilla.
129
411744
3495
07:08
So taste and smell
and other sensory information
and other sensory information
130
416056
3317
07:11
is inextricably entangled
in our conscious mind.
in our conscious mind.
131
419397
3087
07:14
So on one hand, we can actually use this.
132
422508
2926
07:17
We can use these conscious experiences,
133
425458
2469
07:19
use this data, exploit it
by adding vanilla instead of sugar
by adding vanilla instead of sugar
134
427951
4269
07:24
to sweeten our products.
135
432244
1600
07:26
But on the other hand,
136
434823
2326
07:29
with these conscious evaluations,
137
437173
1587
07:30
I still wouldn't know
138
438784
1198
07:32
whether people actually liked
that sugar-reduced milkshake.
that sugar-reduced milkshake.
139
440006
2865
07:36
So how do we get around this problem?
140
444006
1785
07:37
How do we actually assess what's reality
141
445815
2262
07:40
behind these conscious food evaluations?
142
448101
2635
07:42
The key is to remove the barrier
of the conscious mind
of the conscious mind
143
450760
4175
07:46
and instead target the information
in the brain directly.
in the brain directly.
144
454959
3272
07:51
And it turns out
145
459015
1301
07:52
our brain holds a lot
of fascinating secrets.
of fascinating secrets.
146
460340
3067
07:55
Our brain constantly receives
sensory information from our entire body,
sensory information from our entire body,
147
463872
5068
08:00
most of which we don't even
become aware of,
become aware of,
148
468964
2357
08:03
like the taste information
that I constantly receive
that I constantly receive
149
471345
2920
08:06
from my gastrointestinal tract.
150
474289
1869
08:08
And my brain will also act
on all this sensory information.
on all this sensory information.
151
476647
4071
08:13
It will alter my behavior
without my knowledge,
without my knowledge,
152
481274
3436
08:16
and it can increase
the diameter of my pupils
the diameter of my pupils
153
484734
3256
08:20
if I experience something I really like.
154
488014
1960
08:22
And increase my sweat production
ever so slightly
ever so slightly
155
490355
3055
08:25
if that emotion was intense.
156
493434
1867
08:28
And with brain scans,
157
496300
1690
08:30
we can now assess
this information in the brain.
this information in the brain.
158
498014
3266
08:34
Specifically, I have used
a brain-scanning technique
a brain-scanning technique
159
502021
2448
08:36
called electroencephalography,
160
504493
2353
08:38
or "EEG" in short,
161
506870
1833
08:40
which involves wearing a cap
studded with electrodes,
studded with electrodes,
162
508727
3945
08:44
128 in my case.
163
512696
2468
08:47
Each electrode then measures
the electrical activity of the brain
the electrical activity of the brain
164
515957
3611
08:51
with precision down to the millisecond.
165
519592
2601
08:55
The problem is, however,
166
523640
2040
08:57
it's not just the brain
that's electrically active,
that's electrically active,
167
525704
2429
09:00
it's also the rest of the body
as well as the environment
as well as the environment
168
528157
2738
09:02
that contains a lot
of electrical activity all the time.
of electrical activity all the time.
169
530919
2714
09:05
To do my research,
170
533657
1388
09:07
I therefore need
to minimize all this noise.
to minimize all this noise.
171
535069
3000
09:10
So I ask my participants
to do a number of things here.
to do a number of things here.
172
538411
3483
09:14
First off,
173
542427
1159
09:15
I ask them to rest their head
in a chin rest,
in a chin rest,
174
543610
3305
09:18
to avoid too much muscle movement.
175
546939
2421
09:21
I also ask them to, meanwhile,
stare at the center of a computer monitor
stare at the center of a computer monitor
176
549384
3995
09:25
to avoid too much
eye movements and eye blinks.
eye movements and eye blinks.
177
553403
2769
09:28
And I can't even have swallowing,
178
556196
2508
09:30
so I ask my participants
to stick the tongue out of their mouth
to stick the tongue out of their mouth
179
558728
4592
09:35
over a glass bowl,
180
563344
2008
09:37
and then I constantly let
taste stimuli onto the tongue,
taste stimuli onto the tongue,
181
565376
4200
09:41
which then drip off into this bowl.
182
569600
2104
09:43
(Laughter)
183
571728
1484
09:45
And then, just to complete
this wonderful picture,
this wonderful picture,
184
573236
4143
09:49
I also provide my participants with a bib,
185
577403
2587
09:52
available in either pink
or blue, as they please.
or blue, as they please.
186
580014
3103
09:55
(Laughter)
187
583141
4087
09:59
Looks like a normal
eating experience, right?
eating experience, right?
188
587252
2114
10:01
(Laughter)
189
589390
1150
10:03
No, obviously not.
190
591585
1420
10:06
And worse,
191
594546
1349
10:07
I can't even control
what my participants are thinking about,
what my participants are thinking about,
192
595919
3341
10:11
so I need to repeat this taste procedure
193
599284
2111
10:13
multiple times.
194
601419
1150
10:14
Maybe the first time,
they're thinking about the free lunch
they're thinking about the free lunch
195
602958
2831
10:17
that I provide for participating,
196
605813
2161
10:19
or maybe the second time,
they're thinking about Christmas coming up
they're thinking about Christmas coming up
197
607998
3298
10:23
and what to get for Mom
this year, you know.
this year, you know.
198
611320
2900
10:27
But common for each response
is the response to the taste.
is the response to the taste.
199
615109
4127
10:31
So I repeat this taste
procedure multiple times.
procedure multiple times.
200
619260
3267
10:34
Sixty, in fact.
201
622871
1849
10:37
And then I average the responses,
202
625291
1620
10:38
because responses unrelated
to taste will average out.
to taste will average out.
203
626935
2904
10:42
And using this method,
204
630307
1651
10:43
we and other labs,
205
631982
2524
10:46
have investigated how long a time
it takes from "food lands on our tongue"
it takes from "food lands on our tongue"
206
634530
3503
10:50
until our brain has figured out
which taste it's experiencing.
which taste it's experiencing.
207
638057
2979
10:53
Turns out this occurs within the first
already 100 milliseconds,
already 100 milliseconds,
208
641639
3214
10:56
that's about half a second
before we even become aware of it.
before we even become aware of it.
209
644877
2976
11:00
And next up, we also investigated
210
648268
1812
11:02
the taste difference between sugar
and artificial sweeteners
and artificial sweeteners
211
650104
3799
11:05
that in our setup taste extremely similar.
212
653927
2276
11:08
In fact, they tasted so similar
213
656563
2031
11:10
that half my participants
could only barely tell the taste apart,
could only barely tell the taste apart,
214
658618
3579
11:14
while the other half simply couldn't.
215
662221
2325
11:17
But amazingly,
216
665015
1761
11:18
if we looked across
the entire group of participants,
the entire group of participants,
217
666800
3126
11:21
we saw that their brains
definitely could tell the taste apart.
definitely could tell the taste apart.
218
669950
3801
11:26
So with EEG and other
brain-scanning devices
brain-scanning devices
219
674895
2859
11:29
and other physiological measures --
220
677778
2160
11:31
sweat and pupil size --
221
679962
1171
11:33
we have new gateways to our brain.
222
681157
2015
11:35
Gateways that will help us
remove the barrier of the conscious mind
remove the barrier of the conscious mind
223
683625
3691
11:39
to see through the biases of people
224
687340
2183
11:41
and possibly even capture
subconscious taste differences.
subconscious taste differences.
225
689547
2780
11:44
And that's because we can now measure
people's very first response to food
people's very first response to food
226
692689
4311
11:49
before they've become conscious of it,
227
697024
1817
11:50
and before they've started rationalizing
why they like it or not.
why they like it or not.
228
698865
3166
11:54
We can measure people's
facial expressions,
facial expressions,
229
702476
2175
11:56
we can measure where they're looking,
230
704675
2497
11:59
we can measure their sweat response,
231
707196
2000
12:01
we can measure their brain response.
232
709220
2400
12:04
And with all these measures,
233
712030
2063
12:06
we are going to be able
to create tastier foods,
to create tastier foods,
234
714117
2338
12:08
because we can measure
whether people actually like
whether people actually like
235
716479
2397
12:10
that sugar-reduced milkshake.
236
718900
1737
12:12
And we can create healthier foods
without compromising taste,
without compromising taste,
237
720661
4103
12:16
because we can measure the response
to different sweeteners
to different sweeteners
238
724788
2773
12:19
and find the sweetener that gives
the response that's more similar
the response that's more similar
239
727585
3103
12:22
to the response from sugar.
240
730712
1293
12:24
And furthermore, we can just help
create healthier foods,
create healthier foods,
241
732029
2675
12:26
because we can help understand
how we actually sense food
how we actually sense food
242
734728
2967
12:29
in the first place.
243
737719
1267
12:31
Which we know surprisingly little about.
244
739533
2667
12:34
For example, we know
that there are those five basic tastes,
that there are those five basic tastes,
245
742589
3331
12:37
but we strongly suspect
that there are more,
that there are more,
246
745944
2243
12:40
and in fact, using our EEG setup,
we found evidence that fat,
we found evidence that fat,
247
748211
4977
12:45
besides being sensed
by its texture and smell,
by its texture and smell,
248
753212
2587
12:47
is also tasted.
249
755823
1269
12:49
Meaning that fat could be
this new sixth basic taste.
this new sixth basic taste.
250
757553
3381
12:53
And if we figure out
how our brain recognizes fat and sugar,
how our brain recognizes fat and sugar,
251
761522
4357
12:57
and I'm just dreaming here,
252
765903
1317
12:59
but could we then one day
253
767244
1492
13:00
create a milkshake with zero calories
that tastes just like the real deal?
that tastes just like the real deal?
254
768760
4038
13:06
Or maybe we figure out that we can't,
255
774894
2278
13:09
because we subconsciously detect calories
256
777196
2570
13:11
via our receptors
in our gastrointestinal tract.
in our gastrointestinal tract.
257
779790
2784
13:15
The future will show.
258
783137
1400
13:17
Our conscious experience of food
259
785978
2825
13:20
is just the tip of the iceberg
of our total sensation of food.
of our total sensation of food.
260
788827
4964
13:25
And by studying this total sensation,
261
793815
2307
13:28
conscious and subconscious alike,
262
796146
2876
13:31
I truly believe that we can make
tastier and healthier foods for all.
tastier and healthier foods for all.
263
799046
4509
13:35
Thank you.
264
803579
1151
13:36
(Applause)
265
804754
5166
ABOUT THE SPEAKER
Camilla Arndal Andersen - NeuroscientistInstead of asking them what they think, Camilla Arndal Andersen covers her subjects in sensors to reveal their unfiltered and subconscious response to food.
Why you should listen
Tapping into the subconsciousness, Camilla Arndal Andersen has found evidence that the brain registers even the smallest taste differences. Her work has also found evidence that fat could be a new sixth basic taste -- seemingly registered by its taste, in addition to its texture and smell.
Arndal Andersen performs these experiments at her lab in Brabrand, Denmark, and as a scientist at DuPont Nutrition and Biosciences ApS. She does it with the ultimate goal to understand how our brain registers sugar and fat, to engineer healthier food without compromising taste.
Camilla Arndal Andersen | Speaker | TED.com