Neuro-magic: Magician uses magic tricks to study the brain’s powers of perception and memory

A magician is using his knowledge of magic theory and practice to investigate the brain’s powers of observation.

Hugo Caffaratti, engineer and semi-professional magician from Barcelona, Spain, has embarked on a PhD with the University of Leicester’s Centre for Systems Neuroscience.

Hugo has 12 years of experience working with magic – specialising in card tricks – and is a member of the Spanish Society of Illusionism (SEI-ACAI).

The engineer also has a longstanding interest in neuroscience and bioengineering, having taken a Master’s degree in Biomedical Engineering at University of Barcelona.

He hopes to combine his two interests in his PhD thesis project, which covers a new field of Cognitive Neuroscience: Neuro-Magic.

As part of his work, he will investigate how our brains perceive what actually happens before our eyes – and how our attention can be drawn away from important details.

He also plans to study “forced choice” - a tool often used by magicians where we are fooled into thinking we have made a free choice.

Among other experiments, Hugo will ask participants to watch videos of card trick performances, while sitting in front of an eye-tracker device.

This will allow him to monitor where our attention is focused during illusions – and how our brain can be deceived when our eyes miss the whole picture.

Hugo said: “I have always been interested in the study of the brain. It is amazing to be involved in the process of combining the disciplines of neuroscience and magic.

“I am really interested in the fields of decision making and forced-choice. It is incredible that many times a day we make a decision and feel free. We do not realise that we have been forced to make that decision.

“I am constructing an experiment to study what happens when we make forced decisions – to try and find the reasons for it. I am thinking about which kinds of tricks I know could be useful to give more insights about brain function.”

He will work under the tutelage of Professor Rodrigo Quian Quiroga, director of the Centre for Systems Neuroscience.

Professor Quian Quiroga’s recent work on memory formation was the topic of his recent book “Borges and memory” (MIT Press) and was also featured on the front page of the international science publication Scientific American.

Professor Rodrigo Quian Quiroga said: “I am very interested in connections between science and the arts. Last year, for example, we organized an art and science exhibition as a result of a 1-year rotation in my lab of visual artist Mariano Molina. Hugo’s PhD will look at decision-making and attention – and although he is doing his first steps in neuroscience, I think he already has a lot of expertise in this area based on his training as a magician.

“Magic theory has thousands of years of experience. Magicians have been answering similar questions that we have in the lab, and they have an intuitive knowledge of how the mind works. Hugo will likely bring a fresh new view on how to address questions we deal with in neuroscience.”

Hugo is also keen to carry on with his work in magic while studying for his PhD, and is hoping to perform in bars in Leicester while staying here.

He has also applied for membership with The Magic Circle – a prestigious magic society of London. He will have to sit exams to prove his magical mettle in order to join the exclusive club.

The great illusion of the self

As you wake up each morning, hazy and disoriented, you gradually become aware of the rustling of the sheets, sense their texture and squint at the light. One aspect of your self has reassembled: the first-person observer of reality, inhabiting a human body.

As wakefulness grows, so does your sense of having a past, a personality and motivations. Your self is complete, as both witness of the world and bearer of your consciousness and identity. You.

This intuitive sense of self is an effortless and fundamental human experience. But it is nothing more than an elaborate illusion. Under scrutiny, many common-sense beliefs about selfhood begin to unravel. Some thinkers even go as far as claiming that there is no such thing as the self.

In these articles, discover why “you” aren’t the person you thought you were.

Scientists advance the art of magic with a study of Penn and Teller’s ‘cups and balls’ illusion

Cognitive brain researchers have studied a magic trick filmed in magician duo Penn & Teller’s theater in Las Vegas, to illuminate the neuroscience of illusion. Their results advance our understanding of how observers can be misdirected and will aid magicians as they work to improve their art.

The research team was led by Dr. Stephen Macknik, Director of the Laboratory of Behavioral Neurophysiology at Barrow Neurological Institute, in collaboration with fellow Barrow researchers Hector Rieiro and Dr. Susana Martinez-Conde, Director of the Laboratory of Visual Neuroscience. The study, titled “Perceptual elements in Penn and Teller’s “Cups and Balls” magic trick” was published today, Feb 12th 2013, as part of the launch of PeerJ, a new peer reviewed open access journal in which all articles are freely available to everyone. “Cups and Balls,” a magic illusion in which balls appear and disappear under the cover of cups, is one of the oldest magic tricks in history, with documented descriptions going back to Roman conjurors in 3 B.C. “But we still don’t know how it really works in the brain,” says Macknik, “because this is the first, long overdue, neuroscientific study of the trick.”

The discovery concerns the way magicians manipulate human cognition and perception. The “Cups and Balls” trick has many variations, but the most common one uses three balls and three cups. The magician makes the balls pass through the bottom of cups, jump from cup to cup, disappear from a cup and turn up elsewhere, turn into other objects, and so on. The cups are usually opaque and the balls brightly colored. Penn & Teller’s variant is performed with three opaque and then with three transparent cups. “The transparent cups mean that visual information about the loading of the balls is readily available to the brain, yet still the spectators cannot see how the trick is done!” said Martinez-Conde.

Magicians have performed and systematically developed the art and theory of this illusion for thousands of years, but each new generation of conjurers offers new insights and hypotheses about how and why it works for the audience. Here the scientists turned the power of the scientific method to the illusion. The experiments tracked when and where observers looked during video clips portraying specific element of the performance, filmed by a NOVA scienceNOW TV crew. By quantifying how well observers tracked the loading and unloading of balls with and without transparent cups, the scientists determined that some aspects of the illusion were even more powerful at controlling attention than aspects originally predicted by the magician.

The end result is that cognitive scientists now have an improved understanding of how (and by how much) observers can be misdirected. In addition, this knowledge can help magicians further hone their art.

Pioneering research helps to unravel the brain’s vision secrets

A new study led by scientists at the Universities of York and Bradford has identified the two areas of the brain responsible for our perception of orientation and shape.

Using sophisticated imaging equipment at York Neuroimaging Centre (YNiC), the research found that the two neighbouring areas of the cortex — each about the size of a 5p coin and known as human visual field maps — process the different types of visual information independently.

The scientists, from the Department of Psychology at York and the Bradford School of Optometry & Vision Science established how the two areas worked by subjecting them to magnetic fields for a short period which disrupted their normal brain activity. The research which is reported in Nature Neuroscience represents an important step forward in understanding how the brain processes visual information.

Attention now switches to a further four areas of the extra-striate cortex which are also responsible for visual function but whose specific individual roles are unknown.

The study was designed by Professor Tony Morland, of York’s Department of Psychology and the Hull York Medical School, and Dr Declan McKeefry, of the Bradford School of Optometry and Vision Science at the University of Bradford. It was undertaken as part of a PhD by Edward Silson at York.

Researchers used functional magnetic resonance imaging (fMRI) equipment at YNiC to pinpoint the two brain areas, which they subsequently targeted with magnetic fields that temporarily disrupt neural activity. They found that one area had a specialised and causal role in processing orientation while neural activity in the other underpinned the processing of shape defined by differences in curvature.

(Photo: Image courtesy of Brian A. Wandell, Serge O. Dumoulin and Alyssa A. Brewer)

Professional athletes have extraordinary skills for rapidly learning complex and neutral dynamic visual scenes

Evidence suggests that an athlete’s sports-related perceptual-cognitive expertise is a crucial element of top-level competitive sports. When directly assessing whether such experience-related abilities correspond to fundamental and non-specific cognitive laboratory measures such as processing speed and attention, studies have shown moderate effects leading to the conclusion that their special abilities are context-specific. We trained 308 observers on a complex dynamic visual scene task void of context and motor control requirements3 and demonstrate that professionals as a group dramatically differ from high-level amateur athletes, who dramatically differ from non-athlete university students in their capacity to learn such stimuli. This demonstrates that a distinguishing factor explaining the capacities of professional athletes is their ability to learn how to process complex dynamic visual scenes. This gives us an insight as to what is so special about the elite athletes’ mental abilities, which allows them to express great prowess in action.

Full article

(Image: Getty)

Uncovering the secrets of 3D vision: How glossy objects can fool the human brain

It’s a familiar sight at the fairground: rows of people gaping at curvy mirrors as they watch their faces and bodies distort. But while mirrored surfaces may be fun to look at, new findings by researchers from the Universities of Birmingham, Cambridge and Giessen, suggest they pose a particular challenge for the human brain in processing images for 3D vision.

The researchers have taken advantage of the unusual visual behaviour of curved mirrors to study stereopsis: the process by which the brain combines images from the two eyes to see in 3D.

The work, published online in the Proceedings of the National Academy of Sciences (PNAS), used mathematical analysis and perceptual measurements to show that people often see the ‘wrong’ shape for glossy objects (like chrome bumpers or brass door knobs) because of the way the brain employs ‘quality control’ mechanisms when it views the world with two eyes. This reveals how the brain checks the ‘usefulness’ of the signals it receives from the senses, explaining why we sometimes misperceive shapes and distances. It also has some connections with the design of robotic systems.

‘We often think that the 3D information we get from having two eyes provides the gold standard for seeing in depth; but glossy objects pose a difficult challenge to the brain because the stereoscopic information often indicates depths that don’t match the physical shape of the object’ explains Dr Andrew Welchman, a Wellcome Trust Senior Research Fellow at the University of Birmingham. ‘We found that the brain is sometimes ‘fooled’ into seeing the wrong 3D shape, but this depends on statistical properties of the stereo images that indicate how ‘useful’ the information is,’ he adds.

To carry out the project, the team developed mathematical models that calculate the pattern of reflections seen when viewing glossy objects, and measured the perceived 3D appearance of these shapes.

‘When a curved mirrored object reflects its surroundings, the reflections appear at a different depth than the glossy surface itself. This makes it difficult for the brain to work out the true 3D distance to the surface’ explains Dr Alex Muryy, a research fellow at Birmingham who conducted the analyses. ‘We found that even simple objects can produce very complex depth profiles, and reflections can behave very differently from normal stereoscopic information.’ Understanding these differences provided the key to reveal the generalised way in which the brain analyses incoming information to judge the circumstances in which information should be trusted.

‘Stereoscopic information is often highly informative, but in certain circumstances it can tell us the wrong thing or be unreliable. The challenge is therefore to understand how the brain knows when it should or should not trust this 3D information,’ says Professor Roland Fleming, Giessen University in Germany. ‘We have uncovered signals that are likely to be important in guiding the brain’s use of the information by studying glossy objects. In particular, we can understand people’s misperceptions because in these circumstances 3D reflections fall within the normal range of values, meaning that the brain takes the depth signals at face value.’

Honey bees trained to stick out their tongues for science

Biologists at Bielefeld University have trained honey bees to stick out their tongues when their antennae touch an object.

The tactile conditioning study was conducted by a team from the lab of Volker Dürr, professor for biological cybernetics at Bielefeld, and will allow researchers to investigate how the honey bees use touch in pattern recognition and sense memory.

"We work with honey bees because they are an important model system for behavioural biology and neurobiology," explained Dürr. "They can be trained. If you can train an insect to respond to a certain stimulus, then you can ask the bees questions in the form of ‘Is A like B? If so, stick your tongue out’."

The process by which a bee sticks out its tongue when faced with a stimulus is known as the proboscis extension response. It can be conditioned in the bees as a response to a particular textured surface using sugar water. Each time a harnessed honey bee’s antennae touched the surface, the bee was given sugar water. Eventually the bee extends its tongue whenever it touches the right surface.

Currently the biologists are hoping to use the response to find out more about how bees use antennae movements to gather information about their surroundings.

"It is clear that if a bee touches something with an antenna, a finely textured structure, the bee has to move it to get the information it wants," adds Dürr. "We don’t fully understand the relevance of this movement."

Why Old People Get Scammed

Despite long experience with the ways of the world, older people are especially vulnerable to fraud. According to the Federal Trade Commission (FTC), up to 80% of scam victims are over 65. One explanation may lie in a brain region that serves as a built-in crook detector. Called the anterior insula, this structure—which fires up in response to the face of an unsavory character—is less active in older people, possibly making them less cagey than younger folks, a new study finds.

Both FTC and the Federal Bureau of Investigation have found that older people are easy marks due in part to their tendency to accentuate the positive. According to social neuroscientist Shelley Taylor of the University of California, Los Angeles, research backs up the idea that older people can put a positive spin on things—emotionally charged pictures, for example, and playing virtual games in which they risk the loss of money. “Older people are good at regulating their emotions, seeing things in a positive light, and not overreacting to everyday problems,” she says. But this trait may make them less wary.

To see if older people really are less able to spot a shyster, Taylor and colleagues showed photos of faces considered trustworthy, neutral, or untrustworthy to a group of 119 older adults (ages 55 to 84) and 24 younger adults (ages 20 to 42). Signs of untrustworthiness include averted eyes; an insincere smile that doesn’t reach the eyes; a smug, smirky mouth; and a backward tilt to the head. The participants were asked to rate each face on a scale from -3 (very untrustworthy) to 3 (very trustworthy).

In the study, appearing online in the Proceedings of the National Academy of Sciences, the “untrustworthy” faces were perceived as significantly more trustworthy by the older subjects than by the younger ones. The researchers then performed the same test on a different set of volunteers, this time imaging their brains during the process, to look for differences in brain activity between the age groups. In the younger subjects, when asked to judge whether the faces were trustworthy, the anterior insula became active; the activity increased at the sight of an untrustworthy face. The older people, however, showed little or no activation.

Men and women explore the visual world differently

Everyone knows that men and women tend to hold different views on certain things. However, new research by scientists from the University of Bristol and published in PLoS ONE indicates that this may literally be the case.
Researchers examined where men and women looked while viewing still images from films and pieces of art. They found that while women made fewer eye movements than men, those they did make were longer and to more varied locations.

These differences were largest when viewing images of people. With photos of heterosexual couples, both men and women preferred looking at the female figure rather than the male one. However, this preference was even stronger for women.

While men were only interested in the faces of the two figures, women’s eyes were also drawn to the rest of the bodies - in particular that of the female figure.

Felix Mercer Moss, PhD student in the Department of Computer Science who led the study, said: “The study represents the most compelling evidence yet that, despite occupying the same world, the viewpoints of men and women can, at times, be very different.

“Our findings have important implications for both past and future eye movement research together with future technological applications.”