Dec 27, 2020 11:33 PM
(This post was last modified: Dec 28, 2020 05:34 AM by C C.)
How do you see colour? Differently than everyone else
https://bigthink.com/surprising-science/...-see-color
EXCERPT: . . . So is that colour now? We'd get very different answers to this question depending on whom we asked. A physicist (with disarming concision) would say: "Yes, that's colour. Now let me get back to discovering the theory of everything." For physicists, what matter does with light is absolutely sufficient for measuring colour and encapsulating it in a dry number. It's just as well a neurobiologist is standing next to the physicist. This is his answer:
"Colour starts very simply. A photon lands in your eye. In the blink of an eye, if you'll pardon the expression, it crosses its dark interior and hits the retina. If it's lucky, it will hit a very specific part of the retina: one of the tens of millions of photoreceptors that are just waiting for beams of light to strike them. Some of those photoreceptors (known as cones because of their shape) only react more strongly to photons carrying a certain amount of energy. My eye and yours (assuming that we aren't colour blind) have three types of these cones. The photon we're tracking was carrying quite a lot of energy, towards the upper limit of what our eyes can see. It also just so happens that it hit a receptor specializing in deciphering that type of high-energy photon. There it dislocated the bent arm of a special particle, strategically placed in the folds of the membranes that fill the receptor. [...] a single particle, but it was completely sufficient for the entire cell to vibrate with excitement ... lightning-fast, the cone sent news of the photon's kick onwards, and, like a chain reaction, in silent collisions and separations of electrical impulses, that news travelled to the brain so that the brain could think: 'Blue!'"
It's beautiful, isn't it? While for the physicist, the colour of my lesser purple emperor [butterfly] was obvious from the moment its wings voraciously devoured all the photons except for the 'blue' ones, true colourful delight was only possible when that light signal – via many tangled chemical reactions and electrical impulses – reached the brain. And there's more! Some colours are actually formed in there, too.
Between violet and red I've always been unnerved by pink. [...] You either love it or hate it – there's not much room in the world for pink neutrality. But in terms of its physical basis, pink really is a masterpiece of colour. Let's start by saying that pink doesn't exist. Such a colour should not exist. Look at a rainbow – the sequence of colours that make up white light when you place a prism in its path, a pyramid of transparent glass. Red, orange, yellow, green, blue, indigo, violet. There's no pink.
Among the colours of the rainbow – so-called 'visible colours' – we will never find pink, purple, lilac or magenta – these are all so-called 'extra-spectral colours'. They don't exist as a single specific wavelength of light, one specific energy load of a photon. We'll also never see purple or pink if our eyes are only bombarded with photons of a single colour, bearing a single amount of energy. Physically, this means that we can't build a source of light (such as a laser) that, by producing radiation with a single specific wavelength, will produce pink light. Pinks and purples can only be produced when two cones are stimulated at once – the ones sensitive to high-energy photons (known as blue cones) and those sensitive to red (red cones). The brain adds the rest of the story itself by filling a new colour (a purple or pink one) into the empty space between violet and red, between the opposite ends of the light spectrum.
It's quite possible that each of us sees these non-spectral colours differently. [...] Has our perception of pinks in one way and not another been shaped by the evolution of our species? [...] When it comes to colours, evolution might have a great deal more to say, precisely by giving the brain absolute power over where and how we perceive colour.
The brain and grey strawberries. There's a picture of some strawberries in front of me. It has a sea-green glow, as if the strawberries are being lit by a beam of turquoise light. The fruits are dark-red, my brain has no doubt about it. Even if I know that's physically not true. [...] Does that kind of colour – that is, red – actually exist? Let's add some fuel to this fire.
I once carried out an experiment in which I showed a similar illusion to several dozen people. I asked them to show the colour they thought they'd seen (by moving a few colour sliders) on a computer screen, when in fact they had been looking at grey. A degree of fluctuation was to be expected – just because of the imprecise nature of the method used by subjects to indicate the colour. But it turned out that each person saw a completely different 'red' in place of the grey, and sometimes it wasn't even red but a certain shade of violet or purple. Does this mean that in a given unequivocal physical situation, many colours exist – as many as the number of people looking at it?
[...] That's quite a terrifying view of the world, but also a fascinating one. ... the widespread belief that women are better at distinguishing between the slightest shades of colour isn't really defensible. Because it's quite possible that we all have our own colourful cosmoses. We only agree on what to name the colours [...] It's not impossible that looking into the head of a random person and seeing the world through their tinted glasses would be a similar shock for the average person as seeing reality through the eyes of someone who's colour blind. We take too much of our visual perception of the world around us as a physical certainty – but colour isn't just about physics. It's a dance: of photons, chemical particles, electrical impulses, turbulent cytoplasms and ancient whims of the brain. There are simply too many elements involved for it to work in an identical way for each of us... (MORE - details)
Why some people hear colors and taste words
https://www.popsci.com/tags/fall-2020/
INTRO: For a small group of people, sensations entangle themselves in baffling ways. The written numeral 2 might evoke a flash of purple; an audible C sharp note could conjure a finger prick. Some with this condition, called synesthesia, even taste spoken words: The name Sam, for example, might elicit a sweet flavor.
How exactly some people “feel” smells or “taste” names is still generally unclear. There’s no gold standard test to diagnose the condition, which only adds to the mystery. University of Michigan cognitive psychologist David Brang says he gets emails all the time from folks asking if their peculiar sensations are the result of such swapping. “It’s a mixing of the senses,” he says, making the disorder “very difficult to reverse engineer.”
The current theory posits that synesthetes’ brains have extra connections. When you see a word, your retina and optic nerve send that information to the visual cortex, which creates the image you see. Then your noggin’s face- and color-recognition unit, the fusiform gyrus, puts it into context. Extra connections there might simultaneously send signals to, say, both the color- and word-focused regions. Those extra pathways can pigment terms, weaponize musical notes, or even ruin a first date with a rather putrid-tasting name.
This story appears in the Fall 2020, Mysteries issue of Popular Science.
Getting opposite-sex body in VR study caused gender identity shifts
https://bigthink.com/surprising-science/...lity-study
SUMMARY POINTS: New research shows that experiencing an opposite-sex body in virtual reality impacted the subject's gender identity. Scientists find that experiencing an opposite-sex body can affect a person's gender identity. A new study utilized virtual reality to get subjects to feel like they had a stranger's body. The researchers found that people's sense of their own gender became more balanced after the experiments. (MORE)
https://bigthink.com/surprising-science/...-see-color
EXCERPT: . . . So is that colour now? We'd get very different answers to this question depending on whom we asked. A physicist (with disarming concision) would say: "Yes, that's colour. Now let me get back to discovering the theory of everything." For physicists, what matter does with light is absolutely sufficient for measuring colour and encapsulating it in a dry number. It's just as well a neurobiologist is standing next to the physicist. This is his answer:
"Colour starts very simply. A photon lands in your eye. In the blink of an eye, if you'll pardon the expression, it crosses its dark interior and hits the retina. If it's lucky, it will hit a very specific part of the retina: one of the tens of millions of photoreceptors that are just waiting for beams of light to strike them. Some of those photoreceptors (known as cones because of their shape) only react more strongly to photons carrying a certain amount of energy. My eye and yours (assuming that we aren't colour blind) have three types of these cones. The photon we're tracking was carrying quite a lot of energy, towards the upper limit of what our eyes can see. It also just so happens that it hit a receptor specializing in deciphering that type of high-energy photon. There it dislocated the bent arm of a special particle, strategically placed in the folds of the membranes that fill the receptor. [...] a single particle, but it was completely sufficient for the entire cell to vibrate with excitement ... lightning-fast, the cone sent news of the photon's kick onwards, and, like a chain reaction, in silent collisions and separations of electrical impulses, that news travelled to the brain so that the brain could think: 'Blue!'"
It's beautiful, isn't it? While for the physicist, the colour of my lesser purple emperor [butterfly] was obvious from the moment its wings voraciously devoured all the photons except for the 'blue' ones, true colourful delight was only possible when that light signal – via many tangled chemical reactions and electrical impulses – reached the brain. And there's more! Some colours are actually formed in there, too.
Between violet and red I've always been unnerved by pink. [...] You either love it or hate it – there's not much room in the world for pink neutrality. But in terms of its physical basis, pink really is a masterpiece of colour. Let's start by saying that pink doesn't exist. Such a colour should not exist. Look at a rainbow – the sequence of colours that make up white light when you place a prism in its path, a pyramid of transparent glass. Red, orange, yellow, green, blue, indigo, violet. There's no pink.
Among the colours of the rainbow – so-called 'visible colours' – we will never find pink, purple, lilac or magenta – these are all so-called 'extra-spectral colours'. They don't exist as a single specific wavelength of light, one specific energy load of a photon. We'll also never see purple or pink if our eyes are only bombarded with photons of a single colour, bearing a single amount of energy. Physically, this means that we can't build a source of light (such as a laser) that, by producing radiation with a single specific wavelength, will produce pink light. Pinks and purples can only be produced when two cones are stimulated at once – the ones sensitive to high-energy photons (known as blue cones) and those sensitive to red (red cones). The brain adds the rest of the story itself by filling a new colour (a purple or pink one) into the empty space between violet and red, between the opposite ends of the light spectrum.
It's quite possible that each of us sees these non-spectral colours differently. [...] Has our perception of pinks in one way and not another been shaped by the evolution of our species? [...] When it comes to colours, evolution might have a great deal more to say, precisely by giving the brain absolute power over where and how we perceive colour.
The brain and grey strawberries. There's a picture of some strawberries in front of me. It has a sea-green glow, as if the strawberries are being lit by a beam of turquoise light. The fruits are dark-red, my brain has no doubt about it. Even if I know that's physically not true. [...] Does that kind of colour – that is, red – actually exist? Let's add some fuel to this fire.
I once carried out an experiment in which I showed a similar illusion to several dozen people. I asked them to show the colour they thought they'd seen (by moving a few colour sliders) on a computer screen, when in fact they had been looking at grey. A degree of fluctuation was to be expected – just because of the imprecise nature of the method used by subjects to indicate the colour. But it turned out that each person saw a completely different 'red' in place of the grey, and sometimes it wasn't even red but a certain shade of violet or purple. Does this mean that in a given unequivocal physical situation, many colours exist – as many as the number of people looking at it?
[...] That's quite a terrifying view of the world, but also a fascinating one. ... the widespread belief that women are better at distinguishing between the slightest shades of colour isn't really defensible. Because it's quite possible that we all have our own colourful cosmoses. We only agree on what to name the colours [...] It's not impossible that looking into the head of a random person and seeing the world through their tinted glasses would be a similar shock for the average person as seeing reality through the eyes of someone who's colour blind. We take too much of our visual perception of the world around us as a physical certainty – but colour isn't just about physics. It's a dance: of photons, chemical particles, electrical impulses, turbulent cytoplasms and ancient whims of the brain. There are simply too many elements involved for it to work in an identical way for each of us... (MORE - details)
Why some people hear colors and taste words
https://www.popsci.com/tags/fall-2020/
INTRO: For a small group of people, sensations entangle themselves in baffling ways. The written numeral 2 might evoke a flash of purple; an audible C sharp note could conjure a finger prick. Some with this condition, called synesthesia, even taste spoken words: The name Sam, for example, might elicit a sweet flavor.
How exactly some people “feel” smells or “taste” names is still generally unclear. There’s no gold standard test to diagnose the condition, which only adds to the mystery. University of Michigan cognitive psychologist David Brang says he gets emails all the time from folks asking if their peculiar sensations are the result of such swapping. “It’s a mixing of the senses,” he says, making the disorder “very difficult to reverse engineer.”
The current theory posits that synesthetes’ brains have extra connections. When you see a word, your retina and optic nerve send that information to the visual cortex, which creates the image you see. Then your noggin’s face- and color-recognition unit, the fusiform gyrus, puts it into context. Extra connections there might simultaneously send signals to, say, both the color- and word-focused regions. Those extra pathways can pigment terms, weaponize musical notes, or even ruin a first date with a rather putrid-tasting name.
This story appears in the Fall 2020, Mysteries issue of Popular Science.
Getting opposite-sex body in VR study caused gender identity shifts
https://bigthink.com/surprising-science/...lity-study
SUMMARY POINTS: New research shows that experiencing an opposite-sex body in virtual reality impacted the subject's gender identity. Scientists find that experiencing an opposite-sex body can affect a person's gender identity. A new study utilized virtual reality to get subjects to feel like they had a stranger's body. The researchers found that people's sense of their own gender became more balanced after the experiments. (MORE)