̽��ֱ�� of Cambridge - vision

Detect. Lock on. Intercept. ̽��ֱ��remarkable hunting ability of the robber fly

cjb250 — Thu, 09 Mar 2017 16:44:24 +0000

̽��ֱ��robber fly Holcocephala is a relatively small fly – at 6mm in length, it is similar in size of the average mosquito. Yet it has the ability to spot and catch prey more than half a metre away in less than half a second – by comparison to its size, this would be the equivalent of a human spotting its prey at the other end of a football pitch. Even if the prey changes direction, the predator is able to adapt mid-air and still catch its prey.

An international team led by researchers from the ̽��ֱ�� of Cambridge was able to capture this activity by tricking the fly into launching itself at a fake prey – in fact, just a small bead on a fishing line. This enabled the team to witness the fly’s remarkable aerial attack strategy. Their findings are published today in the journal Current Biology.

To read more, see our article on Medium.

See the world through the eyes of a robber fly in the Plant and Life Sciences Marquee at the Cambridge Science Festival, Saturday 18 March 2017.

Reference
Wardill, TJ et al. A novel interception strategy in a miniature robber fly with extreme visual acuity; Current Biology; 9 March 2017; DOI: 10.1016/j.cub.2017.01.050

A small fly the size of a grain of rice could be the Top Gun of the fly world, with a remarkable ability to detect and intercept its prey mid-air, changing direction mid-flight if necessary before sweeping round for the kill.

̽��ֱ��Robber Fly – Top Gun of the fly world

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Believing is Seeing: a Cambridge Shorts film

amb206 — Wed, 09 Nov 2016 08:00:00 +0000

Where does science come from? It comes from inside our heads and our imagination. Science is the unknown, from the biggest scale to the tiniest, waiting to be discovered. It is the process of dreaming how the world works and having the courage to follow that dream. Light is a metaphor for conceiving ideas: letting the outside in and the inside out. Where the two meet is the point of vision: the ability to see what might be.

̽��ֱ��visual imagination isn’t simply frivolous. It is utterly vital to understanding the scientific and technological developments which have allowed our society to evolve, both historically, and in the present day.

This film is a “love letter to scientific daydreaming”; to the importance of creativity in science; to the old-school sci-fi classics, and the way they captured the imagination. This is about the art of being a scientist.

Believing is Seeing is one of four films made by Cambridge researchers for the 2016 Cambridge Shorts series, funded by Wellcome Trust ISSF. ̽��ֱ��scheme supports early career researchers to make professional quality short films with local artists and filmmakers. Dr Eleanor Chan (History of Art) and Dr Marcus Fantham (Chemical Engineering and Biotechnology) collaborated with filmmaker Alex Allen.

Imagination is where ideas start: in the mind’s eye. ̽��ֱ��ability to think creatively – to dream the impossible – is behind the technological developments that have transformed the world. Science, suggests the second of four Cambridge Shorts, is an art.

Believing is Seeing

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‘Red gene’ in birds and turtles suggests dinosaurs had bird-like colour vision

fpjl2 — Wed, 03 Aug 2016 08:35:11 +0000

Earlier this year, scientists used zebra finches to pinpoint the gene that enables birds to produce and display the colour red.

Now, a new study shows the same ‘red gene’ is also found in turtles, which share an ancient common ancestor with birds. Both share a common ancestor with dinosaurs.

̽��ֱ��gene, called CYP2J19, allows birds and turtles to convert the yellow pigments in their diets into red, which they then use to heighten colour vision in the red spectrum through droplets of red oil in their retinas.

Birds and turtles are the only existing tetrapods, or land vertebrates, to have these red retinal oil droplets. In some birds and a few turtle species, red pigment produced by the gene is also used for external display: red beaks and feathers, or the red neck patches and rims of shells seen in species such as the painted turtle.

̽��ֱ��scientists mined the genetic data of various bird and reptile species to reconstruct an evolutionary history of the CYP2J19 gene, and found that it dated back hundreds of millions of years in the ancient archelosaur genetic line - the ancestral lineage of turtles, birds and dinosaurs.

̽��ֱ��findings, published today in the journal Proceedings of the Royal Society B, provide evidence that the ‘red gene’ originated around 250 million years ago, predating the split of the turtle lineage from the archosaur line, and runs right the way through turtle and bird evolution.

Scientists say that, as dinosaurs split from this lineage after turtles, and were closely related to birds, this strongly suggests that they would have carried the CYP2J19 gene, and had the enhanced ‘red vision’ from the red retinal oil.

This may have even resulted in some dinosaurs producing bright red pigment for display purposes as well as colour vision, as seen in some birds and turtles today, although researchers say this is more speculative.

“These findings are evidence that the red gene originated in the archelosaur lineage to produce red for colour vision, and was much later independently deployed in both birds and turtles to be displayed in the red feathers and shells of some species, going from seeing red to being red,” says senior author Dr Nick Mundy, from the ̽��ֱ�� of Cambridge’s Department of Zoology.

“This external redness was often sexually selected as an ‘honest signal’ of genuine high quality in a mate,” he says.

̽��ֱ��previous research in zebra finches showed a possible link between red beaks and the ability to break down toxins in the body, suggesting external redness signals physiological quality, and there is some evidence that colouration in red-eared terrapins is also linked to honest signalling.

“ ̽��ֱ��excellent red spectrum vision provided by the CYP2J19 gene would help female birds and turtles pick the brightest red males,” says Hanlu Twyman, the PhD student who is lead author on the work.

̽��ֱ��structure of retinas in the eye includes cone-shaped photoreceptor cells. Unlike mammals, avian and turtle retinal cones contain a range of brightly-coloured oil droplets, including green, yellow and red.

These oil droplets function in a similar way to filters on a camera lens. “By filtering the incoming light, the oil droplets lead to greater separation of the range of wavelengths that each cone responds to, creating much better colour sensitivity,” explains Mundy.

“Humans can distinguish between some shades of red such as scarlet and crimson. However, birds and turtles can see a host of intermediate reds between these two shades, for example. Our work suggests that dinosaurs would have also had this ability to see a wide spectrum of redness,” he says.

Over hundreds of millennia of evolution, the CYP2J19 gene was independently deployed to generate the red pigments in the external displays of some bird species and a few turtle species. ̽��ֱ��scientists say their data indicate that co-option of CYP2J19 for red colouration in dinosaurs would also have been possible.

̽��ֱ��ancestral lineage that led to scaly lizards and snakes split from the archosaur line before turtles, and, as the findings suggest, before the origin of the red gene. These reptiles either lack retinal oil droplets, or have yellow and green but not red.

However, the crocodilian lineage split from the archelosaur line after turtles, yet crocodiles appear to have lost the CYP2J19 gene, and have no oil droplets of any colour in their retinal cones.

Mundy says there is some evidence that oil droplets were lost from the retinas of species that were nocturnal for long periods of their genetic past, and that this hypothesis fits for mammals and snakes, and may also be the case with crocodiles.

A gene for red colour vision that originated in the reptile lineage around 250m years ago has resulted in the bright red bird feathers and ‘painted’ turtles we see today, and may be evidence that dinosaurs could see as many shades of red as birds - and perhaps even displayed more red than we might think.

̽��ֱ��excellent red spectrum vision provided by the CYP2J19 gene would help female birds and turtles pick the brightest red males

Hanlu Twyman

Nicole Valenzuela

A Painted Turtle

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At the edge of vision: Struggling to make sense of our cluttered world

cjb250 — Wed, 25 Nov 2015 17:00:00 +0000

Even with 20/20 vision in broad daylight on a clear day, our peripheral vision can be surprisingly poor, particularly when the scene in front of us is cluttered. Now, scientists at the ̽��ֱ�� of Cambridge, UK, Northeastern ̽��ֱ��, Boston, USA, and Queensland Brain Institute, Brisbane, Australia, believe they are a step closer to understanding why this is.

“When objects in our peripheral vision are surrounded by visual clutter, a phenomenon known as ‘visual crowding’ hinders our ability to make sense of what we see,” explains Dr Will Harrison from the ̽��ֱ�� of Cambridge. “Visual crowding is ubiquitous in natural scenes and affects virtually all everyday tasks, including reading, driving and interacting with the environment. But this failure of vision isn’t a problem with our eyes – it represents a processing limit of the brain.”

Image: Focus on the green spot. Without moving your eyes, you should be able to identify the letter ‘A’ on the left side of the display; the same letter is almost impossible to see on the right side of the display.

In a study published today in the journal Current Biology, Dr Harrison and Professor Peter Bex from Northeastern ̽��ֱ�� have shed new light on how constraints in the brain limit our peripheral vision.

̽��ֱ��researchers showed volunteers a series of images with differing levels of visual crowding. To make sure they kept their eyes still, the volunteers were asked to focus on a dot. Beside the dot was a broken ring, like the letter ‘C’, but with the gap positioned at a random orientation. ̽��ֱ��volunteers were asked to estimate the angle at which the gap appeared by freely rotating a second C so that it matched the target as closely as possible. This helped the researchers to measure each individual’s uncrowded perceptual acuity.

To measure crowded perception in the next stage, the C was surrounded by an additional, larger C – a ‘distractor’ – at different orientations and/or distances to the target C. ̽��ֱ��volunteers again rotated a second C until they thought it matched the target. Whereas previous studies looking at crowding had only given binary results – was the observer right or wrong? – this new method enabled the researchers to quantify crowding as a continuous experience.

̽��ֱ��researchers found that when the angle of the target and distractor were similar, observers tended to choose an average of the two orientations. When the target and distractor angles were quite different, observers tended to choose either the correct orientation (that of the target) or they mistakenly reported the orientation of the distractor. However, this effect depended on the target and distractor being positioned very closely together – reports were not influenced by a distractor positioned a large distance away from the target.

Combining the findings with a computational model of how visual neurons represent the visual field, Dr Harrison and Professor Bex found that problems in identifying objects in our peripheral vision are due primarily to a combination of two factors. First, in a crowded scene, our visual resolution is degraded, meaning that we become less precise at locating an object’s detail. Second, we confuse which detail belongs to which object, to the extent that part of one object can appear ‘swapped’ with a part of a different object. Importantly, their model suggests that both factors are caused by the same underlying brain mechanism.

Dr Harrison believes the findings may have implications for quantifying and treating vision disorders, such as age-related macular degeneration (AMD). A large portion of the elderly population suffers from AMD, which causes debilitating central blindness. ̽��ֱ��loss of high-resolution central vision forces AMD sufferers to rely solely on peripheral vision, which is very poor due to visual crowding.

“We hope that in future it may be possible to adapt our methods to quantify the degree to which patients with AMD are visually-impaired,” explains Dr Harrison. “At the moment, it can be difficult to quantify the extent or severity of their visual deficits. Our method would allow a careful examination of the function of AMD patients’ remaining vision, which could in turn lead to better rehabilitation techniques down the track.”

̽��ֱ��research was funded by the National Institutes of Health, USA, and the National Health and Medical Research Council of Australia.

Reference
William J Harrison and Peter J Bex. A unifying model of orientation crowding in peripheral vision. Current Biology; 25 Nov 2015

As you’re driving to work along a busy road, your eyes on the traffic lights ahead, hoping they won’t turn to red, you pass signs warning of roadworks, ads on bus shelters… Suddenly a dog runs out in front of you. What are your chances of seeing it before it’s too late?

When objects in our peripheral vision are surrounded by visual clutter, a phenomenon known as ‘visual crowding’ hinders our ability to make sense of what we see

Will Harrison

Sam Saunders

Advisory Cycle Lanes and Pavements Being Abused On Parry's Lane (cropped)

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Motion dazzle: spotting the patterns that help animals outsmart predators on the run

Anonymous — Wed, 09 Sep 2015 10:34:48 +0000

Many animals use the colours and patterns on their bodies to help them blend into the background and avoid the attention of predators. But this strategy, crypsis, is far from perfect. As soon as the animal moves, the camouflage is broken, and it is much easier for a predator to see and catch it. So how do animals protect themselves when they’re on the move?

Researchers are exploring whether high-contrast patterns during motion, such as stripes and zigzags, may be distorting the predator’s perception of where the animal is going. But, as little is known about such “motion dazzle”, we have built an online game to help shed light on it.

Lessons from war

̽��ֱ��idea is that it may be more effective for animals to focus on preventing capture, rather then preventing detection or recognition, is actually more than 100 years old. It was naturalist Abbott Thayer who suggested that high-contrast patterns may distort the perceived speed or direction of a moving object, making it harder to track and capture.

Such motion dazzle patterns were actually used in World War I and II, where some ships were painted with black and white geometric patterns in an attempt to reduce the number of successful torpedo attacks from submarines. However, due to many other factors affecting wartime naval losses, it is unclear whether motion dazzle patterns actually had the desired effect.

HMS Argus displaying a coat of dazzle camouflage in 1918. wikimedia

What about the natural world? Zebras have bold stripes, and scientists have debated the function of their patterns since Darwin’s time. A recent modelling study suggested that when zebras move, their stripes create contradictory signals about their direction of movement that is likely to confuse predators. There are potentially two visual illusions responsible for this, which could form the basis of motion dazzle effects: the wagon wheel effect and the barber pole illusion.

̽��ֱ��wagon wheel effect is named after Western movies, where the wheels on wagons often appear to be moving backwards. This is because the visual system takes “snapshots” over time and links them to create a continuous scene, in the same manner as recording film. If a wheel spoke moves forward rapidly between sampling events, it will appear to have moved backwards as it will be misidentified as the following spoke.

Wagon Wheel effect explained.

̽��ֱ��barber pole illusion (also known as the aperture effect) occurs because the moving stripes provide ambiguous information about the true direction of movement. These illusory effects produced by stripes could therefore lead to difficulties in judging the speed and movement of a moving target. However, the zebra study was entirely theoretical and didn’t test whether striped patterns actually affected the judgements of real observers.

Dazzle Bug

Surprisingly, the first experimental tests of the effectiveness of motion dazzle patterns weren’t carried out until recently. Some studies have shown that strikingly patterned targets can be more difficult to catch than targets with other patterns in studies using humans as “predators” playing touch screen computer games. However, other studies have found no clear advantage for motion dazzle patterns So although patterns can affect our perception of movement, it’s still not clear which are most effective at doing so.

Can you see the spider? Crypsis can be pretty effective - as long as you don’t move. J Kelley, Author provided

We are addressing the question of which patterns are best for avoiding predators during movement using Dazzle Bug – an online game that asks players to imagine themselves as a predator, trying to catch a moving bug as fast as possible. Each bug has a different body pattern as well as a random pattern of movement. Bugs with easy to catch patterns will disappear, whereas those that are particularly tricky to catch will survive ––just like in nature. Over time, the patterns on the bugs' body will evolve so that they become harder to catch with each successive generation.

This citizen science project will allow us to see what patterns are most effective at evading capture. We can then use these results to look at what visual effects these patterns have, and to see whether these patterns match up with those found on real animals in the wild.

Our findings will offer insight into the role of stripes, which are common in many species. While these patterns may have evolved to confuse the visual perception of a predator, they may also be a result of other selection pressures, such as attracting a mate or regulating body temperature. If striped patterns survive and evolve in the game, this would provide strong evidence that these patterns do act to confuse human predators, perhaps by producing the illusions described above. As motion perception seems to be highly conserved across a wide range of populations, these illusions may occur for many other predators too.

If we find that patterns other than stripes – such as speckles, splotches or zigzags – are most effective in preventing capture, this then leads to new and interesting questions about how these patterns may act to confuse or mislead. Whatever the outcome, Dazzle Bug will provide insight into how bodily patterns may have evolved to help animals to survive life on the go.

Laura Kelley, Research Fellow, ̽��ֱ�� of Cambridge

This article was originally published on ̽��ֱ��Conversation. Read the original article.

̽��ֱ��opinions expressed in this article are those of the individual author(s) and do not represent the views of the ̽��ֱ�� of Cambridge.

A new online game is helping researchers explore whether high-contrast patterns during motion, such as stripes and zigzags, help to protect animals from predators.

Dazzle Bug asks players to imagine themselves as a predator, trying to catch a moving bug as fast as possible

Laura Kelley

Eric Dietrich/wikimedia

Zebras on the run can razzle-dazzle their enemies

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Just made coffee while chatting to a friend? Time to thank your ‘visuomotor binding’ mechanism…

amb206 — Fri, 14 Mar 2014 15:00:00 +0000

We talk about being ‘on automatic’ when we’re describing carrying out a familiar series of actions without being aware of what we’re doing.

Now researchers have for the first time found evidence that a dedicated information highway or ‘visuomotor binding’ mechanism connects what we see with what we do. This mechanism helps us to coordinate our movements in order to carry out all kinds of tasks from dunking a biscuit in your coffee, while maintaining eye contact with someone else, to playing basketball on a crowded court.

̽��ֱ��UCL-led research (published yesterday in the journal Current Biology) was a collaboration between Dr Alexandra Reichenbach, of the UCL Institute of Cognitive Neuroscience, and Dr David Franklin, of the Computational and Biological Learning Lab at Cambridge’s Department of Engineering.

Their research suggests that a specialised mechanism for spatial self-awareness links visual cues with body motion. ̽��ֱ��finding could help us understand the feeling of disconnection reported by schizophrenia patients and could also explain why people with even the most advanced prosthetic limbs find it hard to coordinate their movements.

Standard visual processing relies on us being able to ignore distractions and pay attention to objects of interest while filtering out others. “ ̽��ֱ��study shows that our brains also have separate hard-wired systems to track our own bodies visually even when we are not paying attention to them,” explained Franklin. “This allows visual attention to focus on objects in the world around us rather than on our own movements.”

̽��ֱ��newly-discovered mechanism was identified when three experiments were carried out on 52 healthy adults. In all three experiments, participants used robotic interfaces to control cursors on two-dimensional displays, where cursor motion was directly linked to hand movement. They were asked to keep their eyes fixed on the centre of the screen, a requirement checked by eye tracking. “ ̽��ֱ��robotic virtual reality system allowed us to instantaneously manipulate visual feedback independently of the physical movement of the body,” said Franklin.

In the first experiment, participants controlled two separate cursors – equally close to the centre of the screen – with their right and left hands. Their goal was to guide each cursor to a corresponding target at the top of the screen. Occasionally the cursor or target on each side would jump left or right, requiring participants to take corrective action. Each jump was ‘cued’ by a flash on one side, but this was random and did not always correspond to the side about to change.

Not surprisingly, people reached faster to cursor jumps when their attention was drawn to the ‘correct’ side by the cue. However, reactions to jumps were fast regardless of cuing, suggesting that a separate mechanism independent of attention is responsible for tracking our movements.

“ ̽��ֱ��first experiment showed us that we react very quickly to changes relating to objects directly under our own control, even when we are not paying attention to them,” explained Reichenbach. “This provides strong evidence for a dedicated neural pathway linking motor control to visual information, independently of the standard visual systems that are dependent on attention.”

̽��ֱ��second experiment was similar to the first but introduced changes in brightness to demonstrate the attention effect on the visual perception system. In the third experiment, participants were asked to guide one cursor to its target in the presence of up to four dummy targets or cursors, acting as ‘distractors’ alongside the real ones. In this experiment, responses to cursor jumps were less affected by distractors than responses to target jumps. Reactions to cursor jumps remained strong with one or two distractors but decreased significantly in the presence of four.

“These results provide further evidence of a dedicated visuomotor binding mechanism that is less prone to distractions than standard visual processing,” said Reichenbach. “It looks like the specialised system has a higher tolerance for distractions but in the end it is effected by them. Exactly why we evolved a separate mechanism remains to be seen but the need to react rapidly to different visual clues about ourselves and the environment may have enough to necessitate a separate pathway.”

For more information about this story contact Alexandra Buxton, Office of Communications, ̽��ֱ�� of Cambridge, amb206@admin.cam.ac.uk, 01223 761673

Experiments have identified a dedicated information highway that combines visual cues with body motion. This mechanism triggers responses to cues before the conscious brain has become aware of them.

̽��ֱ��study shows that our brains also have separate hard-wired systems to track our own bodies visually even when we are not paying attention to them.

David Franklin

Jenny Downing

Dunking a cookie into a cup of coffee

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Birds of a feather display only a fraction of possible colours

gm349 — Thu, 23 Jun 2011 07:09:09 +0000

Contrary to our human perception of bird coloration as extraordinarily diverse, a new study reports that bird plumages exhibit only a small fraction (less than a third) of the possible colours birds can observe.

Early lineages of living birds probably produced an even smaller range of colours, but the evolution of innovative pigments and structural (or optical) colours has allowed many birds to create more diverse and colourful plumages over time.

Researchers from the ̽��ֱ�� of Cambridge and Yale ̽��ֱ�� applied a mathematical model of bird vision to estimate the full range – or gamut – of avian plumage coloration and to explore how feather colours changed over the course of evolution.

Mary Caswell Stoddard of the ̽��ֱ�� of Cambridge’s Department of Zoology explained: “Birds are among the most colourful organisms on the planet. To our human eyes, birds seem to possess almost every colour imaginable – but birds see the world very differently than we do.”

Birds have an additional colour cone in their retinas that is sensitive to ultraviolet light, which allows them to see many colours invisible to humans.

Stoddard and co-author Richard Prum of Yale ̽��ֱ�� measured hundreds of plumage colours and analyzed them in a tetrachromatic colour space, which combines raw information about the light feathers reflect with details about the colours birds can see. They found that bird plumage colours fall far short of filling the colour space, leaving vast regions unoccupied.

“Just as a newspaper can only print a fraction of the colours we humans can see, bird feathers can only produce a subset of colours that are theoretically visible to other birds,” said Stoddard. “ ̽��ֱ��intriguing part is thinking about why plumage colours are confined to this subset. Out-of-gamut colours may be impossible to make with available mechanisms, or they may be disadvantageous.”

Over evolutionary time, novel coloration mechanisms have evolved in different groups of birds, allowing their plumages to become more colourful.

Prum stated: “Evolutionary innovations in the form of new pigments and structural colours enabled birds to colonize new areas of avian colour space. In the same way, human clothing was pretty drab before the invention of aniline dyes like mauve, but chemical inventions allowed clothing to become more diverse in colour. Our study documents the history of mechanistic constraints on bird colour diversity.”

Bird plumages may only represent a fraction of bird-visible colours, but how colourful are they compared to other objects in the natural world? For comparison, the researchers analyzed an extensive set of flower colours as seen by birds. They determined that bird feather colours rival the diversity of plant coloration and have achieved some striking colours unattainable by flowers.

“To explore the limits and possibilities of bird coloration is a thrilling venture, and we have much yet to discover,” said Stoddard.

Their findings are reported today, 23 June, in the journal Behavioral Ecology.

Research reveals plumages exhibit less than a third of possible colours birds can see.

Birds are among the most colourful organisms on the planet. To our human eyes, birds seem to possess almost every colour imaginable – but birds see the world very differently than we do.

Mary Caswell Stoddard of the ̽��ֱ�� of Cambridge’s Department of Zoology

David Kjaer

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Guiding the light

ns480 — Sat, 01 Sep 2007 13:40:33 +0000

Incredibly sophisticated in structure and function, the retina's construction has puzzled researchers ever since the finer structures of the eye were first resolved over 150 years ago: the retina is built the ‘wrong’ way around. ̽��ֱ��cells responsible for light sensing are sited at the back of the eye, furthest from the incoming light. An explanation for the ‘inverted retina’ has now been revealed by Dr Jochen Guck, newly arrived at the Cavendish Laboratory, while working with a team of scientists at the ̽��ֱ�� of Leipzig, Germany.

Because of its inverted structure, light has to pass through several cells in the retina before it reaches the photoreceptor cells that capture the image and transmit it to the brain. How does this happen without the light being scattered and distorted? Dr Guck describes the problem: ‘Nobody would put sandwich paper in their camera in front of the film and expect a crisp image – like the one we’re used to seeing. And yet, this is how the retina is constructed.’

An understanding of this enigma has become possible with the invention of a special dual-beam laser trap or ‘Optical Stretcher’ by Dr Guck and colleagues, in which physical, light-transmitting properties can be visualised and measured at the level of a single cell. Using this tool, the researchers discovered that the answer to the mystery lies with specialised, elongated cells known as Müller cells, which span the retina and have an amazingly high refractive index compared with their surroundings. This difference in refractive index effectively means the light ‘bounces’ along the cell and barely leaks.

̽��ֱ��ground-breaking studies, highlighted on the front cover of the Proceedings of the National Academy of Sciences USA, showed that the Müller cells essentially act as a field of miniature optic fibres – lined up in parallel in the direction of the light and traversing the whole retina. They trap the light, guide it down their length, and deliver it to the photoreceptors waiting to receive the stimulus. ‘All these living optical fibres together work like a fibreoptic plate,’ says Dr Guck.

With his move to the Cavendish Laboratory, Dr Guck has brought with him the new expertise of using light to investigate the mechanical and optical properties of living cells and tissues. His research adds to an ongoing initiative within the ̽��ֱ�� to draw physics more deeply into the life sciences.

For more information, please contact Dr Jochen Guck (jg473@cam.ac.uk). This research was published in PNAS (2007) 104, 8287–8292.

Pioneering research shines new light on our understanding of the way we see the world. Optical fibres have now been found to exist in vertebrate eyes, channelling light down their length and delivering it without distortion straight to the cells that ‘see’.

Nobody would put sandwich paper in their camera in front of the film and expect a crisp image – like the one we’re used to seeing. And yet, this is how the retina is constructed.

Dr Guck

pasukaru76

Fiber Optics

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