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By James Gallagher Health and science reporter, BBC News Light passing through the body and into the womb has an important role in the developing eye, US researchers have discovered. A study, published in the journal Nature, showed that mice spending pregnancy in complete darkness had babies with altered eye development. It indicated tiny quantities of light were needed to control blood vessel growth in the eye. The researchers hope the findings will aid understanding of eye disorders. Light or dark? If you could journey inside a mouse or a person, there would not be enough light to see. However, tiny quantities of light do pass through the body. This effect has already been used to film an infection spreading through the body. Now scientists - at the University of California, San Francisco, and Cincinnati Children's Hospital Medical Center - believe that body-penetrating light can alter the development of the eye, at least in mice. Normally, a network of blood vessels known as the hyaloid vasculature is formed to help nourish the retina as it is constructed. However, the blood vessels would disrupt sight if they remained, so they are later removed - like scaffolding from a finished building. BBC © 2013

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 13: Memory, Learning, and Development
Link ID: 17685 - Posted: 01.17.2013

By Cheryl Murphy Enhancing your level of vision on demand sounds like something out of a comic book. Superman, if you recall, had the power to turn his x-ray vision on and off like a light switch. So is x-ray vision possible? I’m sorry to say: no. The ability of our naked eyes to see through layers of objects remains an idea conjured up in the minds of science fiction writers. However, the possibility of training your brain to flip to a heightened level of visual discrimination and detection whenever you want may in fact be a reality. Last month, researchers in Switzerland found that participants who were successfully trained to consciously up-regulate the level of activity in their early visual cortex as seen by neurofeedback on fMRI in real time were also able to voluntarily give their level of visual discrimination and detection a boost. This study may sound like science fiction but it is not. Here is how it was done. Sixteen, young healthy participants with normal or corrected-to-normal vision were told to focus on a central fixation light while they imagined high resolution pictures of changing color, shape and intensity in a particular part of their visual field which the researchers called the target region of interest. They visualized such things as writing their name in the air, a boat sailing on the ocean, patterns of spinning wheels and spirals, a model walking down the runway or their pet. They received on-the-spot visual feedback indicating how well their visualizations were boosting their brain activity to aid in their brain training. By imagining these detailed objects, seven out of the sixteen participants were able to train themselves to consciously up-regulate activity in areas of their early visual cortex over the course of a series of separate training sessions. In essence what the participants did was learn how to jump-start their visual cortex. Once their visual cortex was held at a higher state of activity, it was more sensitive and could better detect other stimuli in the target region of interest where they projected their visualizations. © 2013 Scientific American

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 13: Memory, Learning, and Development
Link ID: 17659 - Posted: 01.08.2013

By James Gallagher Health and science reporter, BBC News Totally blind mice have had their sight restored by injections of light-sensing cells into the eye, UK researchers report. The team in Oxford said their studies closely resemble the treatments that would be needed in people with degenerative eye disease. Similar results have already been achieved with night-blind mice. Experts said the field was advancing rapidly, but there were still questions about the quality of vision restored. Patients with retinitis pigmentosa gradually lose light-sensing cells from the retina and can become blind. The research team, at the University of Oxford, used mice with a complete lack of light-sensing photoreceptor cells in their retinas. The mice were unable to tell the difference between light and dark. Reconstruction They injected "precursor" cells which will develop into the building blocks of a retina once inside the eye. Two weeks after the injections a retina had formed, according to the findings presented in the Proceedings of the National Academy of Sciences journal. Prof Robert MacLaren said: "We have recreated the whole structure, basically it's the first proof that you can take a completely blind mouse, put the cells in and reconstruct the entire light-sensitive layer." BBC © 2013

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 13: Memory, Learning, and Development
Link ID: 17655 - Posted: 01.07.2013

By Christof Koch Unless you have been deaf and blind to the world over the past decade, you know that functional magnetic resonance brain imaging (fMRI) can look inside the skull of volunteers lying still inside the claustrophobic, coffinlike confines of a loud, banging magnetic scanner. The technique relies on a fortuitous property of the blood supply to reveal regional activity. Active synapses and neurons consume power and therefore need more oxygen, which is delivered by the hemoglobin molecules inside the circulating red blood cells. When these molecules give off their oxygen to the surrounding tissue, they not only change color—from arterial red to venous blue—but also turn slightly magnetic. Activity in neural tissue causes an increase in the volume and flow of fresh blood. This change in the blood supply, called the hemodynamic signal, is tracked by sending radio waves into the skull and carefully listening to their return echoes. FMRI does not directly measure synaptic and neuronal activity, which occurs over the course of milliseconds; instead it uses a relatively sluggish proxy—changes in the blood supply—that rises and falls in seconds. The spatial resolution of fMRI is currently limited to a volume element (voxel) the size of a pea, encompassing about one million nerve cells. Neuroscientists routinely exploit fMRI to infer what volunteers are seeing, imagining or intending to do. It is really a primitive form of mind reading. Now a team has taken that reading to a new, startling level. A number of groups have deduced the identity of pictures viewed by volunteers while lying in the magnet scanner from the slew of map­like representations found in primary, secondary and higher-order visual cortical regions underneath the bump on the back of the head. © 2012 Scientific American

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 14: Attention and Consciousness
Link ID: 17647 - Posted: 01.01.2013

By Mark Changizi The human fascination with color never ceases to amaze me. Our perceptual experience is filled with shapes and pitches and textures and timbres and depths and on and on, yet color seems to get the lion share of our excitement and philosophical attention. Color seems somehow more artistic than our other perceptual dimensions; it’s simply wonderful to behold, as evinced by the double rainbow guy; and we can’t resist wondering what it would be like to see dimensions of color beyond our own. In fact, RadioLab recently put out a great show on color that nicely conveys the romance we all have toward it. Question is: Why do we find color so enthralling? One of the reasons may be that the world can seem arbitrarily labeled in color, as if a painter dabbed over everything in order to make it beautiful… and that naturally makes us wonder what a different artist might do. What sort of splendor is a bird—who has an extra dimension of color beyond ours—treated to, for example? While I, too, feel the wonder of color, I don’t share this above intuition about color and its arbitrariness. It’s an unfortunate intuition, one that seeps its way not only into the minds of laymen, but into our “enhancement” products and even the hallowed halls of philosophy. In trying to explain what’s wrong with the intuition, let me begin with a thought experiment concerning a product that gives the wearer “shape enhancement” vision. “With our sunglasses’ shape-enhancement filter, you’ll see the world with more vibrant and interesting shapes. Round things will be rounder, regular polygons more muted…”

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17608 - Posted: 12.17.2012

by Christian Jarrett, Ph.D in Brain Myths Back in the 1990s neuroscientists at the University of Parma identified cells in the premotor cortex of monkeys that had an unusual response pattern. They were activated when the monkeys performed a given action and, mirror-like, when they saw another individual perform that same movement. Since then, the precise function and influence of these neurons has become perhaps the most hyped topic in neuroscience. In 2000, Vilayanur Ramachandran, the charismatic neuroscientist, made a bold prediction: “mirror neurons will do for psychology what DNA did for biology.” He's at the forefront of a frenzy of excitement that has followed these cells ever since their discovery. For many, they have came to represent all that makes us human. Perhaps, in those early heady years, Ramachandran was just getting a little carried away? Not at all. For his 2011 book, The Tell-Tale Brain, Ramachandran took his claims further. In the chapter “The neurons that shaped civilisation”, he argues that mirror neurons underlie empathy, allow us to imitate other people, that they accelerated the evolution of the brain, that they help explain the origin of language, and most impressively of all, that they prompted the great leap forward in human culture that happened about 60,000 years ago. “We could say mirror neurons served the same role in early hominin evolution as the Internet, Wikipedia, and blogging do today,” he concludes. “Once the cascade was set in motion, there was no turning back from the path to humanity.” © Copyright 2002-2012 Sussex Directories, Inc

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 5: The Sensorimotor System
Link ID: 17591 - Posted: 12.11.2012

Amy Maxmen When Bob Marley sang, “I am redder than red,” he probably did not imagine that chemists would one day capture this imagined hue. But researchers have taken a step in that direction, by tweaking a colour-sensing pigment from the human eye to absorb reds of longer wavelengths than those that we can see. “We didn’t expect to get redder than red,” says Babak Borhan, a chemist at Michigan State University in East Lansing, who led the study published today in Science1. The researchers’ red was the product of experiments conducted to understand exactly how colour-sensing pigments in our eyes absorb different hues. The team targeted rhodopsin, a pigment found in the photoreceptor cells of the retina. A rhodopsin molecule is made of proteins called opsins and a chromophore — the part of the molecule responsible for absorbing different wavelengths of light . Together, the two parts translate light into signals for various colours, which are then interpreted by the brain. In the eye, a chromophore called retinal responds to wavelengths ranging from red, at about 560 nanometres, to blue, at about 420 nm. “The question has been: how can we see all of these colours using essentially one molecule, the chromophore?” Borhan says. The attached proteins somehow control the range of light that a chromophore can absorb — from red, to green, to blue; but no one knew exactly how they fine-tuned this absorption ability. Scientists have hypothesized that the shade the chromophore can receive shifts as a result of more than one interaction, such as a change in the shape of the chromophore–protein complex and a change in the positions of electrical charges along the protein molecule. © 2012 Nature Publishing Group

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17584 - Posted: 12.08.2012

By GRETCHEN REYNOLDS Recently, researchers in England set out to determine whether weekend golfers could improve their game through one of two approaches. Some were coached on individual swing technique, while others were instructed to gaze fixedly at the ball before putting. The researchers hoped to learn not only whether looking at the ball affects performance, but also whether where we look changes how we think and feel while in action. Back in elementary school gym class, virtually all of us were taught to keep our eyes on the ball during sports. But a growing body of research suggests that, as adults, most of us have forgotten how to do this. When scientists in recent years have attached sophisticated, miniature gaze-tracking devices to the heads of golfers, soccer players, basketball free throw shooters, tennis players and even competitive sharpshooters, they have found that a majority are not actually looking where they believe they are looking or for as long as they think. It has been less clear, though, whether a slightly wandering gaze really matters that much to those of us who are decidedly recreational athletes. Which is in part why the British researchers had half of their group of 40 duffers practice putting technique, while the other half received instruction in a gaze-focusing technique known as “Quiet Eye” training. Quiet Eye training, as the name suggests, is an attempt to get people to stop flicking their focus around so much. But “Quiet Eye training is not just about looking at the ball,” says Mark Wilson, who led the study, published in Psychophysiology, and is a senior lecturer in human movement science at the University of Exeter in England. “It is about looking at the ball for long enough to process aiming information.” It involves reminding players to first briefly sight toward the exact spot where they wish to send the ball, and then settle their eyes onto the ball and hold them there. Copyright 2012 The New York Times Company

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17548 - Posted: 11.28.2012

by Douglas Heaven Blind people could soon be able to read street signs using an implant that translates the alphabet into Braille and beams an image of the Braille directly to visual neurons at the back of the eye. The implant is a modified version of a class of devices called retinal prostheses, which are used to restore partial sight to people with retinitis pigmentosa. A degenerative eye disease that kills the photoreceptor cells in the retina, RP tends to affect people in early adulthood and can lead to blindness, but leaves intact the neurons that carry visual signals to the brain. Prostheses such as the Argus II, manufactured by Second Sight in Sylmar, California, convert video from a camera mounted on a pair of glasses into electronic signals "displayed" on a 10-by-6 grid of electrodes implanted over a person's retina. This gives users a pixellated view of the world, allowing them to distinguish light and dark regions and even detect features such as doorways. But deciphering letters and words with the prosthesis is slow because of its low resolution. To make this more practical, Thomas Lauritzen of Second Sight and colleagues have come up with a modified version of the Argus II that presents the user with Braille. Since Braille represents letters and numbers as dots in a 3-by-2 grid, it can be displayed using the electrode array of existing Argus implants. The modified implant was tried out on a Braille-reading volunteer who already uses the Argus II. Tested on single letters and words of up to four letters, transmitted in Braille to the retinal implant, he correctly identified the letters 89 per cent of the time and words 60 to 80 per cent of the time. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17527 - Posted: 11.24.2012

By Ben Thomas In the early 1990s, a team of neuroscientists at the University of Parma made a surprising discovery: Certain groups of neurons in the brains of macaque monkeys fired not only when a monkey performed an action – grabbing an apple out of a box, for instance – but also when the monkey watched someone else performing that action; and even when the monkey heard someone performing the action in another room. In short, even though these “mirror neurons” were part of the brain’s motor system, they seemed to be correlated not with specific movements, but with specific goals. Over the next few decades, this “action understanding” theory of mirror neurons blossomed into a wide range of promising speculations. Since most of us think of goals as more abstract than movements, mirror neurons confront us with the distinct possibility that those everyday categories may be missing crucial pieces of the puzzle – thus, some scientists propose that mirror neurons might be involved in feelings of empathy, while others think these cells may play central roles in human abilities like speech. Some doctors even say they’ve discovered new treatments for mental disorders by reexamining diseases through the mirror neuron lens. For instance, UCLA’s Marco Iacoboni and others have put forth what Iacoboni called the “broken mirror hypothesis” of autism – the idea that malfunctioning mirror neurons are likely responsible for the lack of empathy and theory of mind found in severely autistic people. © 2012 Scientific American,

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 5: The Sensorimotor System
Link ID: 17466 - Posted: 11.07.2012

by Rachel Nuwer The dungeon is pitch black—until the dungeon master blazes a torch, confirming your worst fears. A Beholder monster lurches at you, its eyeballs wriggling on tentacular stems. As you prepare to wield your Vorpal sword, where do you focus your gaze: at the monster's head or at its tentacle eyes? Such a quandary from the role-playing game Dungeons & Dragons may seem like a meaningless trifle, but it holds within it the answer to a scientific question. In fact, a father-son team has used images of such monsters to show that most people will look to another creature's eyes, no matter where they are located on the body. "Dungeons & Dragons monsters have eyes all over the place," says Julian Levy, a ninth grader at Lord Byng Secondary School in Vancouver, Canada. Two years ago, Levy's knowledge of the role-playing game led him to a unique solution for solving a basic scientific question: Do people focus their gaze on another person's eyes or on the center of the head, where the eyes just happen to be located? "We were eating dinner and my dad was talking about how, after publishing a paper about gaze tracking, a reviewer said that you could never prove whether people are looking at the eyes or the center of the face," Levy recalls. So he piped up with an idea, offering Dungeons & Dragons characters as an experimental solution. Because many characters have eyes located on their hands, torso, or other areas of the body, a researcher could track viewers' gazes to see what part of the characters they focus on first. © 2010 American Association for the Advancement of Science.

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17439 - Posted: 10.31.2012

by Clare Wilson Why does making direct eye contact with someone give you that feeling of a special connection? Perhaps because it excites newly discovered "eye cells" in the amygdala, the part of the brain that processes emotions and social interactions. This new type of neuron was discovered in a Rhesus macaque. If humans have these neurons too, it may be that they are impaired in disorders such as autism and schizophrenia, which affect eye contact and social interactions. Katalin Gothard, a neurophysiologist at the University of Arizona in Tucson, and her team placed seven electrodes in the amygdala of a Rhesus macaque. The electrodes, each one-tenth the thickness of a human hair, allowed them to record activity in individual neurons as the macaque watched a video featuring another macaque. All the while, the team also tracked the macaque's gaze. Out of the 151 neurons the researchers could distinguish, 23 fired only when the macaque was looking at the eyes of the monkey in the video. Of these neurons, which the team call "eye cells", four fired more when the monkey in the video appeared to be gazing back at the laboratory macaque, as if the two animals were making eye contact. "These are cells that have been tuned by evolution to look at the eye, and they extract information about who you are, and most importantly, are you making eye contact with me," says Gothard. Other eye cells fired depending on whether the monkey in the video was behaving in a friendly, aggressive or neutral manner, but not in response to eye contact. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 14: Attention and Consciousness
Link ID: 17377 - Posted: 10.17.2012

by Douglas Heaven I spy, with my mechanical eye. It seems a simple mechanical change plays a role in sensory perception in fruit flies, and possibly in many other animals, including humans. The eyes of the common fruit fly (Drosophila melanogaster) contain clusters of light-sensitive cells organised into rods. When light strikes one of these cells, it triggers a series of chemical reactions. These cause a protein called a transient receptor potential (TRP) ion channel to open. When it's open, the TRP allows charged particles to flow into the cell, causing the cell to send a signal to the fly's brain. TRP channels play a part in sensory perception in many animals, from nematodes to humans. But nobody knew how the chemical signals make the TRP channel open. Shrinking rods "Everyone's been looking for years and years at the chemical messengers," says Roger Hardie of the University of Cambridge, UK. A mechanical trigger was never considered. "No one thought to look," he says. With Kristian Franze, Hardie found that the chemical signals change the surface area of the cell's outer membrane by destroying some of its constituent molecules. When several cells shrink like this, the entire rod contracts by up to 400 nanometres, a margin big enough to be seen with a microscope. "The whole membrane shrinks," says Hardie. "It's like a little muscle twitching." © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17365 - Posted: 10.13.2012

  Sandrine Ceurstemont, editor, New Scientist TV Think an object can't be in two places at once? This animation shows how the perceived location of a dot is influenced by what's happening around it. In this video, a flashing dot is surrounded by two diamonds that shift across the screen. When they move horizontally, the dot seems to shift sideways and slightly upwards. In a second version, in which the corners of the diamonds are obscured, the dot appears to move diagonally. In fact, the dot never changes place. The illusion is the work of Peter Kohler from Dartmouth College in Hanover, New Hampshire, and his team. Kohler has been trying to determine if the dot's perceived shift in position is caused by the overall motion of the diamonds or that of its components. For example, although the shapes as a whole are moving sideways, viewing the edges in isolation shows that segments of the diamonds are moving upwards. "Our results show that global motion does influence the shift," he says. "But the fact that even the unoccluded diamond does not yield a purely horizontal shift indicates that local signals are also very important." The team now plans to investigate how quickly our brain perceives the shift. "Integration of local and global motion is known to take about 150 milliseconds," says Kohler. "It would be interesting to see if the effect takes a similar amount of time to kick in." By presenting the illusion for very short amounts of time, the researchers will be able to determine if different versions are initially perceived in the same way. "We also have fMRI work under way to identify brain areas that represent the perceived shifted location rather than the actual location," says Kohler. The illusion was recently presented at the European Conference on Visual Perception in Alghero, Italy. © Copyright Reed Business Information Ltd.  

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17312 - Posted: 09.29.2012

By Mary Bates It's an oft-repeated idea that blind people can compensate for their lack of sight with enhanced hearing or other abilities. The musical talents of Stevie Wonder and Ray Charles, both blinded at an early age, are cited as examples of blindness conferring an advantage in other areas. Then there's the superhero Daredevil, who is blind but uses his heightened remaining senses to fight crime. It is commonly assumed that the improvement in the remaining senses is a result of learned behavior; in the absence of vision, blind people pay attention to auditory cues and learn how to use them more efficiently. But there is mounting evidence that people missing one sense don't just learn to use the others better. The brain adapts to the loss by giving itself a makeover. If one sense is lost, the areas of the brain normally devoted to handling that sensory information do not go unused — they get rewired and put to work processing other senses. A new study provides evidence of this rewiring in the brains of deaf people. The study, published in The Journal of Neuroscience, shows people who are born deaf use areas of the brain typically devoted to processing sound to instead process touch and vision. Perhaps more interestingly, the researchers found this neural reorganization affects how deaf individuals perceive sensory stimuli, making them susceptible to a perceptual illusion that hearing people do not experience. These new findings are part of the growing research on neuroplasticity, the ability of our brains to change with experience. A large body of evidence shows when the brain is deprived of input in one sensory modality, it is capable of reorganizing itself to support and augment other senses, a phenomenon known as cross-modal neuroplasticity. © 2012 Scientific American

Related chapters from BP7e: Chapter 9: Hearing, Vestibular Perception, Taste, and Smell; Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 6: Hearing, Balance, Taste, and Smell; Chapter 7: Vision: From Eye to Brain
Link ID: 17281 - Posted: 09.19.2012

Sandrine Ceurstemont, editor, New Scientist TV It's not yet possible to make Silvio Berlusconi disappear, but now a new illusion can shrink his head. Created by Tim Meese and colleagues at Aston University in Birmingham, UK, the animation tricks our brain with moving circles of different sizes before presenting the mind-altering images of his face. To perceive the effect, fix your eyes on the cross in the center of the video. Once the motion stops and the head pictures are flashed on-screen, the image on the left should appear smaller than the one on the right. If you pause the video, you'll notice that in fact both heads are the same size. According to Daniel Baker, a member of the team, the trick occurs because our brain adapts to the size of the moving circles, tiring out the mechanisms that respond to those sizes. So after viewing the large circle on the left, the head presented in its place looks smaller and vice versa. The same type of effect can also alter an object's orientation after staring at tilted patterns. The team was surprised to find that the illusion takes place with any image, regardless of the pattern it's filled in with. "It's rare for an effect to be so general," says Baker. "You could adapt to pictures of kittens and it would still work." © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17260 - Posted: 09.15.2012

by Sara Reardon You can run from a crow that you've wronged, but you can't hide. Wild crows remember human faces in the same way that mammals do. Crows can distinguish human faces and remember how different people treated them, says John Marzluff of the University of Washington in Seattle. To work out how the crows process this information, Marzluff had members of his team wear a latex mask as they captured 12 wild American crows (Corvus brachyrhynchos). The crows learned to associate the captor's mask with this traumatic experience. While in captivity, the crows were fed and looked after by people wearing a different mask. After four weeks, the researchers imaged the birds' brains while they were looking at either the captor or feeder mask. The brain patterns looked similar to those seen in mammals: the feeder sparked activity in areas involved in motivation and reward, whereas the captor stimulated regions associated with fear. The result makes sense, says Kevin McGowan of Cornell Lab of Ornithology in Ithaca, New York. Crows don't mind if humans are in their habitat – but they need to keep a close eye on what we do. Journal reference: Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.1206109109 © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 14: Attention and Consciousness
Link ID: 17243 - Posted: 09.11.2012

By Susana Martinez-Conde and Stephen L. Macknik “There are things in that [wall]paper that nobody knows but me, or ever will. Behind that outside pattern the dim shapes get clearer every day. It is always the same shape, only very numerous. And it is like a woman stooping down and creeping about behind that pattern.” —Charlotte Perkins Gilman, “The Yellow Wallpaper,” 1892 The protagonist in Charlotte Perkins Gilman's short story “The Yellow Wallpaper” suffers from the most notable case of pareidolia in fiction. Pareidolia, the misperception of an accidental or vague stimulus as distinct and meaningful, explains many supposedly paranormal and mystical phenomena, including UFO and Bigfoot sightings and other visions. In Gilman's story, the heroine, secluded in her hideously wallpapered bedroom and having nothing with which to occupy herself, is driven to insanity>—full-blown paranoid schizophrenia>—by the woman behind the yellow pattern. As she descends into madness, she comes to believe that she is imprisoned by the wallpaper. Mental disease can aggravate pareidolia, as can fatigue and sleepiness. After a recent surgery, one of us (Martinez-Conde) noticed faces everywhere, in places as unlikely as the ultrasound images of her left arm during an examination of potential postsurgical blood clots. She realized at once that the ubiquitous faces were the product of lack of sleep and the high titer of pain medication in her bloodstream, so she was more fascinated than concerned. Her doctor agreed but made a note in her file for a different drug regime in the future. Just in case. Luckily, the hospital room's walls were bare, and there was no yellow wallpaper in sight. Our brain is wired to find meaning. Our aptitude to identify structure and order around us, combined with our superior talent for face detection, can lead to spectacular cases of pareidolia, with significant effects in society and in culture. © 2012 Scientific American

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17241 - Posted: 09.11.2012

Sandrine Ceurstemont, editor, New Scientist TV Impossible objects, like those drawn by artist M. C. Escher, don't seem like they could exist in the real world. But Kokichi Sugihara from Meiji University in Kawasaki, Japan, is well known for building 3D versions of these structures. Now a new video shows his latest construction: a gravity-defying roof that seems to attract and balance balls on its edge. When the house is rotated, its true form is revealed. According to Sugihara, this type of ambiguous shape is interesting because we perceive the illusion again even after we have seen what the object really looks like. After studying a variety of these objects, he concludes that our brain seems to choose the most rectangular configuration when it tries to make sense of features that can have different interpretations. The brain trick was presented this week at the European Conference on Visual Perception in Alghero, Italy. If you would like to build your own impossible objects, check out printable copies of Sugihara's designs. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain
Related chapters from MM:Chapter 7: Vision: From Eye to Brain
Link ID: 17234 - Posted: 09.10.2012

By CLAUDIA DREIFUS The developmental psychologist Daphne Maurer made headlines this year with research suggesting that people born with cataracts could improve their eyesight by playing Medal of Honor, the “first-person shooter” video game. But her fame goes far beyond the video screen. Dr. Maurer, 56, director of the Visual Development Lab at McMaster University in Ontario, is an author, with her husband, Charles, of the pioneering 1988 book “The World of the Newborn,” an inventory of what babies sense and experience. In recent years she has been directing a study tracking infants born with visual impairments into later life. This longitudinal study is her attempt to learn how early sensory deprivation affects vision over a lifetime. We spoke in person earlier this year and again by telephone last month. An edited and condensed version of the two conversations follows. How did computer games enter your life? Are you a gamer? No, not at all. I’m a reader. My husband and I don’t have children. So computer games wouldn’t be a part of our lives. I’ve never played one. I can’t imagine enjoying playing one. For more than 25 years, I’ve been an investigator on a longitudinal study following the visual development of infants born with cataracts in their eyes. These youngsters went through a period of temporary visual deprivation. They didn’t get any of that early patterning in the world that regularly sighted infants get. As soon as possible, they received surgeries and corrective contact lenses at Toronto’s Hospital for Sick Children, after which their vision improved. © 2012 The New York Times Company

Related chapters from BP7e: Chapter 10: Vision: From Eye to Brain; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 13: Memory, Learning, and Development
Link ID: 17212 - Posted: 08.28.2012