How your brain decides what is beautiful
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0:02 - 0:04It's 1878.
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0:05 - 0:08Sir Francis Galton
gives a remarkable talk. -
0:09 - 0:13He's speaking to the anthropologic
institute of Great Britain and Ireland. -
0:14 - 0:18Known for his pioneering work
in human intelligence, -
0:18 - 0:20Galton is a brilliant polymath.
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0:22 - 0:23He's an explorer,
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0:23 - 0:25an anthropologist,
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0:25 - 0:27a sociologist,
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0:27 - 0:28a psychologist
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0:28 - 0:30and a statistician.
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0:31 - 0:34He's also a eugenist.
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0:35 - 0:36In this talk,
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0:37 - 0:42he presents a new technique
by which he can combine photographs -
0:42 - 0:44and produce composite portraits.
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0:45 - 0:50This technique could be used
to characterize different types of people. -
0:51 - 0:56Galton thinks that if he combines
photographs of violent criminals, -
0:56 - 0:59he will discover the face of criminality.
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1:00 - 1:02But to his surprise,
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1:02 - 1:05the composite portrait that he produces
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1:06 - 1:07is beautiful.
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1:10 - 1:13Galton's surprising finding
raises deep questions: -
1:14 - 1:15What is beauty?
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1:16 - 1:23Why do certain configurations of line
and color and form excite us so? -
1:24 - 1:26For most of human history,
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1:26 - 1:31these questions have been approached
using logic and speculation. -
1:32 - 1:34But in the last few decades,
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1:34 - 1:37scientists have addressed
the question of beauty -
1:37 - 1:42using ideas from evolutionary psychology
and tools of neuroscience. -
1:43 - 1:46We're beginning to glimpse
the why and the how of beauty, -
1:47 - 1:50at least in terms of what it means
for the human face and form. -
1:51 - 1:53And in the process,
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1:53 - 1:55we're stumbling upon some surprises.
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1:56 - 1:59When it comes to seeing
beauty in each other, -
2:00 - 2:04while this decision is certainly
subjective for the individual, -
2:04 - 2:08it's sculpted by factors that contribute
to the survival of the group. -
2:09 - 2:11Many experiments have shown
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2:11 - 2:15that a few basic parameters contribute
to what makes a face attractive. -
2:16 - 2:22These include averaging, symmetry
and the effects of hormones. -
2:22 - 2:24Let's take each one of these in turn.
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2:27 - 2:28Galton's finding
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2:28 - 2:33that composite or average faces
are typically more attractive -
2:33 - 2:37than each individual face
that contributes to the average -
2:37 - 2:39has been replicated many times.
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2:40 - 2:44This laboratory finding fits
with many people's intuitions. -
2:45 - 2:49Average faces represent
the central tendencies of a group. -
2:50 - 2:54People with mixed features
represent different populations, -
2:54 - 2:57and presumably harbor
greater genetic diversity -
2:57 - 3:00and adaptability to the environment.
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3:00 - 3:05Many people find mixed-race
individuals attractive -
3:05 - 3:07and inbred families less so.
-
3:09 - 3:13The second factor that contributes
to beauty is symmetry. -
3:13 - 3:18People generally find symmetric faces
more attractive than asymmetric ones. -
3:19 - 3:24Developmental abnormalities
are often associated with asymmetries. -
3:24 - 3:27And in plants, animals and humans,
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3:27 - 3:31asymmetries often arise
from parasitic infections. -
3:31 - 3:34Symmetry, it turns out,
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3:34 - 3:37is also an indicator of health.
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3:38 - 3:40In the 1930s,
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3:41 - 3:44a man named Maksymilian Faktorowicz
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3:44 - 3:47recognized the importance
of symmetry for beauty -
3:47 - 3:49when he designed the beauty micrometer.
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3:50 - 3:51With this device,
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3:51 - 3:55he could measure minor asymmetric flaws
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3:55 - 3:59which he could then make up for
with products he sold from his company, -
3:59 - 4:03named brilliantly
after himself, Max Factor, -
4:03 - 4:06which, as you know,
is one of the world's most famous brands -
4:06 - 4:07for "make up."
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4:09 - 4:12The third factor that contributes
to facial attractiveness -
4:12 - 4:14is the effect of hormones.
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4:16 - 4:20And here, I need to apologize
for confining my comments -
4:20 - 4:22to heterosexual norms.
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4:24 - 4:28But estrogen and testosterone
play important roles -
4:28 - 4:31in shaping features
that we find attractive. -
4:32 - 4:36Estrogen produces features
that signal fertility. -
4:36 - 4:39Men typically find women attractive
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4:39 - 4:44who have elements
of both youth and maturity. -
4:44 - 4:48A face that's too baby-like might
mean that the girl is not yet fertile, -
4:49 - 4:51so men find women attractive
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4:51 - 4:55who have large eyes,
full lips and narrow chins -
4:55 - 4:57as indicators of youth,
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4:58 - 5:01and high cheekbones
as an indicator of maturity. -
5:03 - 5:08Testosterone produces features
that we regard as typically masculine. -
5:09 - 5:11These include heavier brows,
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5:11 - 5:12thinner cheeks
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5:12 - 5:14and bigger, squared-off jaws.
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5:14 - 5:16But here's a fascinating irony.
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5:18 - 5:19In many species,
-
5:19 - 5:20if anything,
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5:20 - 5:24testosterone suppresses the immune system.
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5:25 - 5:29So the idea that testosterone-infused
features are a fitness indicator -
5:29 - 5:31doesn't really make a whole lot of sense.
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5:32 - 5:35Here, the logic is turned on its head.
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5:36 - 5:38Instead of a fitness indicator,
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5:38 - 5:41scientists invoke a handicap principle.
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5:43 - 5:46The most commonly cited
example of a handicap -
5:46 - 5:48is the peacock's tail.
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5:49 - 5:53This beautiful but cumbersome tail
doesn't exactly help the peacock -
5:53 - 5:54avoid predators
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5:55 - 5:56and approach peahens.
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5:57 - 6:01Why should such an extravagant
appendage evolve? -
6:02 - 6:04Even Charles Darwin,
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6:04 - 6:08in an 1860 letter to Asa Gray wrote
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6:08 - 6:12that the sight of the peacock's tail
made him physically ill. -
6:12 - 6:15He couldn't explain it
with his theory of natural selection, -
6:15 - 6:17and out of this frustration,
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6:17 - 6:20he developed the theory
of sexual selection. -
6:22 - 6:23On this account,
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6:23 - 6:27the display of the peacock's tail
is about sexual enticement, -
6:27 - 6:33and this enticement means
it's more likely the peacock will mate -
6:33 - 6:35and have offspring.
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6:36 - 6:39Now, the modern twist
on this display argument -
6:39 - 6:44is that the peacock is also
advertising its health to the peahen. -
6:46 - 6:51Only especially fit organisms
can afford to divert resources -
6:51 - 6:54to maintaining such
an extravagant appendage. -
6:55 - 6:59Only especially fit men can afford
the price that testosterone levies -
7:00 - 7:01on their immune system.
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7:02 - 7:04And by analogy, think of the fact
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7:04 - 7:11that only very rich men can afford
to pay more than $10,000 for a watch -
7:11 - 7:13as a display of their financial fitness.
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7:15 - 7:18Now, many people hear these kinds
of evolutionary claims -
7:18 - 7:24and think they mean that we somehow
are unconsciously seeking mates -
7:24 - 7:26who are healthy.
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7:26 - 7:29And I think this idea
is probably not right. -
7:30 - 7:35Teenagers and young adults are not exactly
known for making decisions -
7:35 - 7:37that are predicated on health concerns.
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7:39 - 7:40But they don't have to be,
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7:40 - 7:42and let me explain why.
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7:43 - 7:45Imagine a population
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7:45 - 7:49in which people have three different
kinds of preferences: -
7:49 - 7:53for green, for orange and for red.
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7:54 - 7:55From their point of view,
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7:55 - 7:58these preferences have
nothing to do with health; -
7:58 - 7:59they just like what they like.
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8:00 - 8:04But if it were also the case
that these preferences are associated -
8:04 - 8:07with the different likelihood
of producing offspring -- -
8:07 - 8:10let's say in a ratio of 3:2:1 --
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8:11 - 8:13then in the first generation,
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8:13 - 8:16there would be 3 greens
to 2 oranges to 1 red, -
8:16 - 8:18and in each subsequent generation,
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8:18 - 8:21the proportion of greens increase,
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8:22 - 8:24so that in 10 generations,
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8:24 - 8:2898 percent of this population
has a green preference. -
8:28 - 8:31Now, a scientist coming in
and sampling this population -
8:31 - 8:35discovers that green
preferences are universal. -
8:36 - 8:39So the point about this little
abstract example -
8:40 - 8:44is that while preferences
for specific physical features -
8:44 - 8:47can be arbitrary for the individual,
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8:48 - 8:50if those features are heritable
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8:53 - 8:57and they are associated
with a reproductive advantage, -
8:57 - 8:59over time,
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8:59 - 9:01they become universal for the group.
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9:03 - 9:08So what happens in the brain
when we see beautiful people? -
9:11 - 9:15Attractive faces activate
parts of our visual cortex -
9:15 - 9:17in the back of the brain,
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9:17 - 9:18an area called the fusiform gyrus,
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9:19 - 9:21that is especially tuned
to processing faces, -
9:21 - 9:25and an adjacent area called
the lateral occipital complex, -
9:25 - 9:28that is especially attuned
to processing objects. -
9:29 - 9:30In addition,
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9:30 - 9:35attractive faces activate parts
of our reward and pleasure centers -
9:35 - 9:37in the front and deep in the brain,
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9:38 - 9:41and these include areas
that have complicated names, -
9:41 - 9:43like the ventral striatum,
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9:43 - 9:45the orbitofrontal cortex
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9:45 - 9:48and the ventromedial prefrontal cortex.
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9:49 - 9:53Our visual brain that is tuned
to processing faces -
9:53 - 9:55interacts with our pleasure centers
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9:55 - 9:58to underpin the experience of beauty.
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10:00 - 10:04Amazingly, while we all
engage with beauty, -
10:04 - 10:05without our knowledge,
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10:05 - 10:07beauty also engages us.
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10:08 - 10:11Our brains respond to attractive faces
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10:11 - 10:13even when we're not thinking about beauty.
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10:15 - 10:19We conducted an experiment
in which people saw a series of faces, -
10:19 - 10:21and in one condition,
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10:21 - 10:26they had to decide if a pair of faces
were the same or a different person. -
10:28 - 10:30Even in this condition,
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10:30 - 10:37attractive faces drove neural activity
robustly in their visual cortex, -
10:37 - 10:40despite the fact that they were thinking
about a person's identity -
10:40 - 10:41and not their beauty.
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10:43 - 10:47Another group similarly found
automatic responses to beauty -
10:47 - 10:50within our pleasure centers.
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10:51 - 10:53Taken together, these studies suggest
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10:54 - 10:59that our brain automatically
responds to beauty -
10:59 - 11:01by linking vision and pleasure.
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11:02 - 11:04These beauty detectors, it seems,
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11:04 - 11:06ping every time we see beauty,
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11:06 - 11:09regardless of whatever else
we might be thinking. -
11:11 - 11:17We also have a "beauty is good"
stereotype embedded in the brain. -
11:18 - 11:20Within the orbitofrontal cortex,
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11:20 - 11:22there's overlapping neural activity
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11:22 - 11:26in response to beauty and to goodness,
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11:27 - 11:31and this happens even when people
aren't explicitly thinking -
11:31 - 11:32about beauty or goodness.
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11:34 - 11:38Our brains seem to reflexively
associate beauty and good. -
11:39 - 11:43And this reflexive association
may be the biologic trigger -
11:43 - 11:45for the many social effects of beauty.
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11:46 - 11:50Attractive people receive
all kinds of advantages in life. -
11:52 - 11:54They're regarded as more intelligent,
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11:54 - 11:56more trustworthy,
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11:56 - 12:00they're given higher pay
and lesser punishments, -
12:00 - 12:02even when such judgments
are not warranted. -
12:04 - 12:07These kinds of observations
reveal beauty's ugly side. -
12:08 - 12:10In my lab, we recently found
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12:10 - 12:15that people with minor facial
anomalies and disfigurements -
12:15 - 12:19are regarded as less good, less kind,
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12:19 - 12:23less intelligent, less competent
and less hardworking. -
12:24 - 12:29Unfortunately, we also have
a "disfigured is bad" stereotype. -
12:30 - 12:37This stereotype is probably
exploited and magnified -
12:37 - 12:39by images in popular media,
-
12:40 - 12:43in which facial disfigurement
is often used as a shorthand -
12:43 - 12:46to depict someone of villainous character.
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12:47 - 12:51We need to understand
these kinds of implicit biases -
12:51 - 12:53if we are to overcome them
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12:53 - 12:56and aim for a society
in which we treat people fairly, -
12:56 - 13:01based on their behavior and not
on the happenstance of their looks. -
13:05 - 13:08Let me leave you with one final thought.
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13:09 - 13:11Beauty is a work in progress.
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13:13 - 13:16The so-called universal
attributes of beauty -
13:16 - 13:21were selected for during the almost
two million years of the Pleistocene. -
13:22 - 13:27Life was nasty, brutish
and a very long time ago. -
13:28 - 13:33The selection criteria
for reproductive success from that time -
13:33 - 13:35doesn't really apply today.
-
13:36 - 13:37For example,
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13:37 - 13:42death by parasite is not one
of the top ways that people die, -
13:42 - 13:44at least not in the technologically
developed world. -
13:46 - 13:48From antibiotics to surgery,
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13:48 - 13:52birth control to in vitro fertilization,
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13:52 - 13:55the filters for reproductive success
are being relaxed. -
13:56 - 13:59And under these relaxed conditions,
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13:59 - 14:03preference and trait combinations
are free to drift -
14:03 - 14:05and become more variable.
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14:05 - 14:10Even as we are profoundly
affecting our environment, -
14:11 - 14:14modern medicine
and technological innovation -
14:14 - 14:16is profoundly affecting
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14:16 - 14:20the very essence of what it means
to look beautiful. -
14:21 - 14:24The universal nature of beauty is changing
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14:24 - 14:27even as we're changing the universe.
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14:29 - 14:30Thank you.
-
14:30 - 14:34(Applause)
- Title:
- How your brain decides what is beautiful
- Speaker:
- Anjan Chatterjee
- Description:
-
Anjan Chatterjee uses tools from evolutionary psychology and cognitive neuroscience to study one of nature's most captivating concepts: beauty. Learn more about the science behind why certain configurations of line, color and form excite us in this fascinating, deep look inside your brain.
- Video Language:
- English
- Team:
- closed TED
- Project:
- TEDTalks
- Duration:
- 14:47
Brian Greene edited English subtitles for How your brain decides what is beautiful | ||
Brian Greene approved English subtitles for How your brain decides what is beautiful | ||
Brian Greene edited English subtitles for How your brain decides what is beautiful | ||
Camille Martínez accepted English subtitles for How your brain decides what is beautiful | ||
Camille Martínez edited English subtitles for How your brain decides what is beautiful | ||
Camille Martínez edited English subtitles for How your brain decides what is beautiful | ||
Leslie Gauthier edited English subtitles for How your brain decides what is beautiful | ||
Leslie Gauthier edited English subtitles for How your brain decides what is beautiful |