Qualia personal
Peter H.M. Brooks
before. It seems that the question has now been answered, we do not see the
world in the same way, our qualia are personal. My red may be quite a
different quale from your red.
Now that that's out of the way we can investigate the implications. I
am quite surprised by the result as I had imagined that other people's
qualia were much the same as mine - from their descriptions and reaction to
the world. I have tended to dismiss different reactions as being for other
reasons - philistinism or perversity for example. However, if people truly
do see a delicate watercolour landscape as just grey blobs; smell (and
consequently taste) a truffle omelette as similar to a mcshite hamburger and
hear Bach as similar to badly played bagpipes then it is no wonder they
can't appreciate them! There seems little point in trying to teach such
people either - as with trying to teach a pig to dance, it just wastes your
time and annoys the pig.
It must also be true that one could measure the level of acuity of all
the senses and discover the fortunate elite with the finest senses who are
best placed by their genes to be artists, chefs, musicians and perfumers.
Training then would not be wasted on those incapable of reaching such
heights of perfection.
The article follows:
In the realm of your senses
New Scientist vol 181 issue 2432 - 31 January 2004, page 40
We have all wondered whether other people see, smell and touch the
world in the same way we do. Now there are some real clues to the answer,
says Richard Hollingham
IT'S a classic philosophical conundrum: how does my perception of the
world differ from yours? Take a red rose, for example. We can probably agree
it's red rather than blue, but what exactly is "red", and do I see the same
red as you? And what about the distinctive smell - is my sense of what
constitutes a rose's scent the same as yours?
Philosophers have been wrestling with this question for centuries.
Sensory scientists, too, have long been interested in why people report such
different experiences of the same odours or flavours. Is it purely
subjective, or based on some objective difference in their sensory
experiences?
The obvious answer is that there is no way of knowing because sensory
experiences are inherently private. But biologists have recently taken a
fresh look at the question and concluded that we can know. Sensory
experiences are highly individualised. "No two people live in the same
sensory world," says Paul Breslin, a neuroscientist at the Monell Chemical
Senses Center in Philadelphia. "The world you see, the foods you taste, the
odours you smell - all are perceived in a way unique to you."
It's all down to our DNA. In the past few years geneticists have
unearthed huge numbers of genes involved in the perception of taste, smell,
touch and vision. Olfactory receptor genes, for example, account for around
3 per cent of the total - only the immune system takes up more houseroom.
And not only are sensory genes vastly abundant, they are highly variable
too. This means that individuals rarely have exactly the same set of sensory
genes. And, crucially, individual genetic repertoires are now being linked
to differences in the way people report their experiences of the world. Some
scientists even think that the set of sensors you inherit has a profound
effect on your life and personality.
If all this is too much to cope with, sit down and have a drink. It's
as good an example as any.
"I love gin and tonic," announces geneticist Dennis Drayna - he uses
his favourite tipple to explain his research. He works at the National
Institute on Deafness and Other Communication Disorders in Rockville,
Maryland, and his speciality is bitter-tasting substances. "I could even
drink the tonic without the gin," he says. "I really like the bitter taste."
But not everyone shares his predilections. Give a single concentration
of any bitter chemical, such as the quinine in tonic, to a selection of
people and they will have remarkably different responses. "Most will tell
you it's moderately bitter, some will say it's not bitter at all and a few
will yell at you for trying to poison them," Breslin says.
That much has been known for a long time. But Drayna, Breslin and
others have now started linking these subjective differences in taste
perception to the genes that code for taste receptor proteins in taste buds.
They work with perhaps the most famous bitter flavour,
phenylthiocarbamide or PTC. This chemical was discovered in the 1930s by
Arthur Fox, an industrial chemist at DuPont who was researching artificial
sweeteners. Fox discovered that some of his colleagues found the chemical
incredibly bitter while others, including himself, could not taste it at
all.
The ability to taste PTC was long thought to be a case of simple
Mendelian inheritance. People with two copies of the recessive "non-taster"
version were unable to taste PTC; others could. But this distinction has
turned out to be too simplistic. Even though the trait is broadly "bimodal"
with reasonably distinct taster and non-taster groups, there is a lot of
variation within the groups. "If the concentration is high enough [about 360
parts per million] everyone can taste it," Drayna says. Some tasters can
detect PTC at the vanishingly small concentration of 18 parts per billion.
Drayna set out to find the genetic source of this variation. He asked
267 people whose genomes had already been sequenced to take a taste test in
which they had to sort six cups of water, three containing a known
concentration of PTC and three without. He repeated the test at different
dilutions to find each person's taste threshold. Then he compared the
results with the sequence of a region on chromosome 7 previously identified
as the location of the genes that code for bitterness receptors. As a result
the team identified the PTC receptor gene and also found it came in five
different "flavours" that differed from each other by a single base pair.
These alterations were sufficient to explain the difference between the
volunteers' taste thresholds.
The PTC gene codes for only one of 23 different bitterness receptors,
which gives an idea of the possible diversity. Initial analysis of other
taste receptors hints at equally wide variance. So it looks as though your
tastes in food really are your own.
Olfaction, too, is proving to be hugely variable, though in a subtly
different way. Humans can distinguish around 10,000 different smells via 400
receptor proteins lining the nasal cavity (see Diagram). But it has long
been known that not everyone smells the same smells - and now geneticists
have shown that this could be because everyone has a different set of
receptors.
Olfactory receptor genes are distinctive and easy to spot from their
DNA sequence. So it came as a surprise when the human genome turned out to
contain about 1000 such genes. How did this tally with the 400 known
receptor proteins? It turned out that around 600 are "pseudogenes" -
sequences that look like genes and are inherited like genes but have lost
their function. For sensory scientists this was an intriguing discovery, as
pseudogenes are known to have lost their function very recently. So a team
at the Weizmann Institute in Rehovot, Israel, wondered whether some
olfactory pseudogenes were still functional in some people, and whether this
tallied with differences in what they were able to smell.
In a study published in Nature Genetics (vol 34, p 143), the team
identified 51 pseudogenes that are functional in some people. Then they took
189 ethnically diverse volunteers and examined their olfactory receptor
genes. They found that each person had a unique combination of functioning
pseudogenes, giving them an individualised repertoire of smell receptors.
However, team member Yoav Gilad is not yet prepared to associate this
genetic variability with the results of smell tests. "Although studies have
shown big differences between smelling abilities, unlike with PTC, there's
no proof that this is genetically based," he says. Although he concedes that
genetics almost certainly plays a role, "there are a lot of other
environmental and psychological factors as well". For example, when people
are given coloured water and clear water that smelt identical when sniffed
blindly, a majority say the coloured water smells stronger.
Of course, an innate revulsion to tonic water or heightened ability to
smell a rose is unlikely to have a major impact on your life. However,
differences in other senses could prove more significant.
In humans there is one sense we rely on more than others - sight. But
light perception and colour vision can differ markedly between individuals,
and again it's down to genes. Stephen Tsang of Columbia University in New
York City studies the genetics of responses to light intensity. He has
discovered that many of the genes involved in light perception come in
several different forms, and this can lead to huge individual variation in
light sensitivity. "Our response to light varies from those who can detect a
single photon to others who have a disease known as congenital stationary
night blindness, which severely impairs their ability to see in dim light,"
Tsang says. "Most of us living in the constant glow of cities don't realise
we might have some degree of impairment."
Colour perception, too, is hugely variable, and not just for the 8 per
cent of people (mostly men) with some degree of colour blindness. "Even
among individuals with normal vision, tests of colour perception show a wide
variation in how colours are seen," says geneticist Samir Deeb of the
University of Washington in Seattle, who studies colour vision. Again, most
of these differences appear to have a genetic basis.
Colour is detected by millions of cone cells in the retina and in a
normal person there are three types, responding to red, green and blue
light. This makes humans trichromatic and in theory allows us to distinguish
between more than 2 million different colours. Blue cones are very uniform
but there are at least four versions of the gene that encodes the red visual
pigment and four versions of the green. Because these genes are carried on
the X chromosome, and men have only one X chromosome, the variant genes are
readily expressed in men and often lead to subtle impairments in colour
vision.
But these variants don't just cause defects - they may give some women
enhanced colour vision. Because women have two X chromosomes, it is possible
for one X to carry the normal genes and the other to carry one or other of
the variants. This means some women have an extra type of cone, making them
potentially tetrachromatic. Deeb has now begun research on these
super-sighted women and says the phenomenon may not be unusual. "Around 15
per cent of women are carriers of colour vision deficiency," he says.
"Looking at 43 of these, two showed evidence of tetrachromacy."
So what does a tetrachromatic woman see that the rest of us don't? "I
wish I could tell you," laughs Deeb, although he says it is likely that they
are able to distinguish colours that mere trichromatics cannot. They could,
for example, be able to tell the difference between two seemingly identical
shades of green. Unfortunately, the rest of us will never know what we're
missing.
Meanwhile at McGill University in Montreal, Canada, mice are having
their tails dipped in hot water to study their reaction to pain. Jeffrey
Mogil's team has tested 12 strains of mice and found that while some strains
flick their tails out of hot water in 2 seconds, other strains take anything
up to 6. A series of experiments led him to conclude that this variation in
pain perception must be genetic, and he has now set out to find its source.
Recent evidence suggests that humans too have varying perceptions of
pain, and that those differences have a biological origin. Bob Coghill of
Wake Forest University School of Medicine in Winston-Salem, North Carolina,
took 17 volunteers and applied a heat source to the backs of their calves.
Then he raised the temperature in steps until it was 49 °C - about the most
human skin can take without burning - and asked the volunteers to rate the
amount of pain on a scale of 1 (no pain) to 10 (excruciating). The
variability in their responses was striking: some found a small temperature
rise unbearable while one subject did not feel any discomfort.
By repeating the experiment with the volunteers in an MRI brain
scanner, Coghill found a clear correlation between the amount of pain people
reported and the amount of brain activity that accompanies it in the
cerebral cortex. Those most susceptible showed much more activity. "The
perception of pain varies by a strikingly large amount," Mogil says, "and
these experiments show that those differences are real and objective."
Across at least four of the senses, then, there is enormous scope for
individual variation. Your combination of visual, olfactory, taste and pain
receptors is almost certainly different from mine. For Paul Breslin this
implies something profound. "If you consider that almost everything we learn
from birth is dependent on our sensory systems, then our individual sensory
differences are all the more interesting," he says. In other words, we are
partly a product of our senses. Breslin suggests that these differences
could even affect many of the choices we make in our lives. "There is a
significant visual and olfactory component in the kinds of foods we like,
the activities we take part in, the music we enjoy and even who we mate
with," he says. If that component is decided by our genes, the logical
conclusion is that, to some extent, we are genetically predetermined to
prefer certain things or people. Our freedom to choose is limited.
There are also implications for consciousness research. How the
physical world becomes our private sensory experiences - what philosophers
call "qualia" - is often seen as the key to understanding consciousness. So
if qualia are produced by the output of our senses, and people sense the
world in ways we can pin down objectively, does that help us understand
individual conscious experiences?
Possibly, says philosopher David Chalmers of the University of
Arizona. "We might one day be able to say that a person with a particular
set of genes has a particular type of consciousness," he says. But if this
is so, you have new problems to solve, "particularly when it comes to trying
to find out what someone else's consciousness is like". This question, known
as the "problem of other minds", also lies at the heart of consciousness
research.
The sensory world we live in is also complicated by the brain's
interpretation of what the senses are telling it. Rather than simply report
the output of our senses to the mind, the brain puts its own spin on the
world. In a dramatic demonstration of this, Daniel Simons of Harvard
University showed volunteers a video of a ball game and asked them to watch
one team intently. After about 45 seconds a woman dressed in a gorilla suit
walked in front of the camera. Around half the viewers completely missed the
gorilla. The rods and cones in their eyes obviously detected it, but their
brains chose to ignore it.
And so perhaps the age-old problem remains intractable. The red I see
might be different to the red you see, but perhaps our minds still interpret
the sensory input to give us a common red experience. You could say that
"red" will always be a pigment of the imagination.
Richard Hollingham
Thur
> people either - as with trying to teach a pig to dance, it just wastes
your
> time and annoys the pig.
There can be no black and white regarding the senses for all but
those few with some sort of brain damage.
If humans do not need to perceive colour, or taste, or hearing,
then they do not push their perceptions, and their capabilities
decline.
Primitive peoples whose lives depend upon such senses have
been reported to have highly developed eyesight and hearing,
for example.
I do not know this, but these people who are then overtaken by
our beautiful modern world might allow such sensitivities to
become dulled.
Immersing any human into a world of art must help to increase
the visual sense. The senses that were dulled were not damged,
and the brain's connections can be restored.
You are perhaps, giving up on the human race too soon.
Society Can rescue itself from itself.
I do agree though, that there are a good proportion of people who
seem to live in a world of dimness and shallow perception.
It takes a deal of spirit not to become depressed by the two-syllable,
pig-grunting masses.
If one just one of these people finds the time to become interested
in art, then I cheer it as a victory for civilization.
Cheer up.
Thur
Incidentally:-
http://www.bbc.co.uk/radio4/science/hearingcolours.shtml
As many as one in 2000 people has an extraordinary condition in which the
five senses intermingle. This major two part series reveals how synaesthesia
is changing our understanding of the world of neuroscience
Thur
"Peter H.M. Brooks" <fustbar...@e3.net.nz> wrote in message
news:4028...@news.iconz.co.nz...
>Deleted article for space<
keith o'connor
It supports the concepts of multi-culturalism and pluralism - even
secularism can be included under its tent provided it is not applied too
dogmatically.
It provides some ammunition (using military metaphor as an example of the
metaphorical basis of language) against the autocrats e.g. my style of art
is the only art etc.
--
take care: Keith
The eye should not be lead where there is nothing to see.
Robert Henri - The Art Spirit
"Peter H.M. Brooks" <fustbar...@e3.net.nz> wrote in message
news:4028...@news.iconz.co.nz...
Peter H.M. Brooks
"Thur" <a@spamless.z> wrote in message
news:ku0Wb.2620$vo1...@newsfep4-winn.server.ntli.net...
>
>
> Incidentally:-
> http://www.bbc.co.uk/radio4/science/hearingcolours.shtml
> As many as one in 2000 people has an extraordinary condition in which the
> five senses intermingle. This major two part series reveals how
synaesthesia
> is changing our understanding of the world of neuroscience
>
quale can be very different for different people.
--
"That," he said, "is a distinguished civilian, John Stuart Mill. He
was an authority on political economy."
"Why?" asked Bertie.
"Well, he wanted to be; he thought it was a useful thing to be."
Bertie gave an expressive grunt, which conveyed his opinion that
there was no accounting for tastes. - Saki, The Toys of Peace
Dilettante
> excellent post:
quotation from chairman brooks:
"...maybe, in Yankland, the law does protect people from their own stupidity - a
very foolish thing for the law to do, particularly in Yankland...."
keith o'connor
would be perfect if it were not for them - "but you are perfect!" - damm.
--
take care: Keith
The eye should not be lead where there is nothing to see.
Robert Henri - The Art Spirit
"Dilettante" <hu...@myself.com> wrote in message
news:ba63903f.04021...@posting.google.com...
Peter H.M. Brooks
attributing my quote to somebody else.
Since I am not, I'm happy to see you pay tribute to your master.
--
"No!" she replied proudly and mockingly, "but I have the whip."
She drew it quickly from the pocket of her fur-coat, and struck him
in the face with the handle. He rose, and drew back a couple of paces. -
"Venus in Furs" Leopold von Sacher-Masoch
Dilettante
> It is no longer stupidity - its genetics - my parents did it - not me - I
> would be perfect if it were not for them - "but you are perfect!" - damm.
Let's also not forget brooks's persistent anti-american bitterness
(this Yankland thing). should we all emulate him and start attacking
each other's nationalities too?
Diletttante
keith o'connor
towards Americans - there was a war time song with the line "the yanks are
coming ..." and it was used in a fun happy gay way.
--
take care: Keith
The language of art is not a scientifically accurate language. The language
of art is based upon the application of tendencies and as such creates more
variety of interpretation between people than absolute agreement between
people.
Keith O'Connor
"Dilettante" <hu...@myself.com> wrote in message
news:ba63903f.04021...@posting.google.com...
Peter H.M. Brooks
> Yank as far as my memory serves was used in Canada as a friendly term
> towards Americans - there was a war time song with the line "the yanks are
> coming ..." and it was used in a fun happy gay way.
>
relaxed about their nicknames. They realise that they don't have to be
offended simply because other people may not like certain things about their
country - they can rise above that and see themselves as individuals,
separate from the country they happen to be born in.
Naughty of me to bring such a sophisticated approach to a lad who will find
it far over his head, but I think to stretch the little fellows slightly
from time to time is good for them. I'll excuse myself on the grounds that
you started it by using 'gay' in the sense that some less gifted types have
rather a lot of trouble coming to terms with.
--
Sylvia: "You must think me a stupid American bitch."
Neighbour: "Not at all, I assumed that you were Canadian" - dialogue from
the film 'Sylvia'
keith o'connor
condescending; arrogant etc. It's those little fellows, without them my dark
side would never get any exercise.
--
take care: Keith
The language of art is not a scientifically accurate language. The language
of art is based upon the application of tendencies and as such creates more
variety of interpretation between people than absolute agreement between
people.
Keith O'Connor
"Peter H.M. Brooks" <fustbar...@e3.net.nz> wrote in message
news:402bb8cf$1...@news.iconz.co.nz...
Peter H.M. Brooks
> Looks like we are in a race to see which one of us can be the most
> condescending; arrogant etc. It's those little fellows, without them my
dark
> side would never get any exercise.
>
my ankles can they?
WTF do you mean about 'arrogant', 'condescending', 'clever', 'funny' etc.
etc."?
Can you measure that sort of stuff??
Do you get thickos complainint that they really can't hack it??
? - ^ <<
>>/? *
fuc, y
you too -[]=
"{} clever shit...~~~g`-Hate your fucking guts you clever fuccccck,.
mean
it
too
climb
down\
no
arrogant
shitttt.
No, poor me.
PaY THE
price,
you
sad
failed
irony
you...
ph...@e3.net.nz
thank youuuu
sue you lovely lady - Sue you try it you sue youd fucck you s-< you. Just
ryyyy. j. Just Try to
Pretend you bastard that this you fuc,\
k.
Sue Make it payu them
K,\
Pay.l Sue you jus t... Now...
You .. otheriwse screw seu sue sue Sue, you new nopwwn nowwddre
Dilettante
> Naughty of me to bring such a sophisticated approach to a lad who will find
> it far over his head,
this from a grown up tries not to offend
D.
Dilettante
> Looks like we are in a race to see which one of us can be the most
> condescending; arrogant etc. It's those little fellows, without them my dark
> side would never get any exercise.
After I saw how brooks treated the guy with the coop problem in the
"Am Ia sucker" thread, I realised what he was made of. It need not
connote arrogance to point that out.
D.
Dilettante
It would not matter where you came from. there are people everywhere
who feed their ego on the misfortunes of others.
D.
Peter H.M. Brooks
There is something to be said for those to whom irony is the dark side of
the moon.
Neil Maxwell
<fustbar...@e3.net.nz> wrote:
>LOL!
>
>There is something to be said for those to whom irony is the dark side of
>the moon.
Your sig reminds me that I haven't pulled out my collection of Saki
short stories for about 10 years or more. Maybe we can take up a
collection and send a copy to Dil as a primer in clever irony. If
nothing else, it might keep him out of the internet cafe for a few
days...
Neil Maxwell - I don't speak for my employer
Peter H.M. Brooks
"Neil Maxwell" <neil.m...@nospam.intel.com> wrote in message
news:smiq20d97klnogqfc...@4ax.com...
I think he would be over Dillies head though.
Dilettante
>
> There is something to be said for those to whom irony is the dark side of
> the moon.
but little to be said for a pile of cliches like this.
D.