The science of magic: It's not all hocus pocus

May 1, 2013 by Michele Barker, The Conversation
Pick a card, any card – and maybe a research paper too. Credit: Micah Taylor

Think of your favourite magic trick. Is it as grandiose as David Copperfield's Death Saw, or is it as simple as making a coin disappear in front of your very eyes?

These two very different tricks have the same effect; they delight and astound, leaving the audience to ponder (usually unsuccessfully):

How did they do that?

But while magic has entertained us for thousands of years, it also has a long and colourful history of informing areas of scientific research, from to treatment of paralysis.

How could such a seemingly innocuous form of entertainment affect such diverse areas?

Uncovering magic's secrets

In 1893, French psychologist Alfred Binet managed to co-opt five of the country's most prominent to help him understand illusions.

His interest in the development of cinema led him to record and view their performances frame by frame.

He was able to analyse the movement of the magicians as an animated sequence with the hope of understanding how audiences could be deceived by the magic performed right in front of them.

In his 1894 article La Psychologie de la Prestidigitation, Binet concluded that magical illusions were created by so many little optical tricks that:

to perceive them could be quite as difficult as to count with the naked eye the grains of sand on the seashore.

Alfred Binet. Credit: Wikimedia Commons

A 2008 article by a group of research psychologists argued that it was time to acknowledge magic's influence on the cognitive sciences, opening a new field called the "science of magic".

In 2010, Stephen Macknik and Susana Martinez-Conde coined the term "neuromagic" in their book Sleights of Mind.

The pair published some of their research findings in Nature, co-authored with not one, but four of the world's leading magicians.

Like Binet more than a century before, they saw the value of working directly with magicians.

Penn and Teller expose sleight of hand techniques.

Perceiving blindness

Magic has finally emerged from the box labelled "entertainment" and now shines a light on one of the most perplexing areas of mind studies – perception.

Perception is key in many magic techniques. Audience members will follow a magician's hand when he or she gestures in a curved line – but not when the line is straight, to give just one example.

Scientific attempts to understand perceptual processes have largely relied on functional Magnetic Resonance Imaging (fMRI) – medical imaging techniques that identify brain activity through changes in its blood flow.

Scientists also study eye movements using head-mounted eye trackers to ascertain objects of visual focus.

But much of our visual perception cannot be understood as a direct fit between seeing something and that thing registering in our attention.

Looking but not seeing

Our everyday perception is littered with episodes that psychologists call "inattentional blindness" and "change blindness".

Pay very close attention.

In other words, something happens in front of us but because our attention is elsewhere, we don't register having seen it.

Neurologically speaking, when change occurs gradually it is referred to as change blindness, and one of the best examples of this is British psychologist Richard Wiseman's colour card changing trick.

If the change occurs abruptly, it's called inattentional blindness.

Do you see the trick?

An experiment by American psychologists Daniel Simons and Christopher Chabris is by far the most famous illustration of this, and won them the Ig Nobel Prize in 2005.

But while the colour card changing "trick" and Simons and Chabris' experiment aren't technically magic tricks, magic provides an arena for observing how our visual perception is often at odds with the objects and events happening before our very eyes.

Misdirection is a standard technique of the magician's palette and demonstrates the perceptual rift between looking at something and attending to it and it is this rift that fascinates neuroscientists and neuropsychologists.

Commonly thought to be about speed – isn't the hand quicker than the eye? – misdirection is actually more about leading us to focus only on a particular area.

When a magician throws a ball into the air and it seemingly vanishes, the trick works because the audience is following the magician's gaze – not his hand.

After really throwing the ball into the air numerous times and then simply performing the same movement in every way but without the ball, most people will see a ball fly into the air and disappear.

The magician has misdirected your gaze into following his and deployed a combination of inattentional and change blindness.

A neurological perspective

What we also learn from this neurologically is that implied movement stimulates brain functioning in much the same way as watching an actual movement.

That your gaze can differ from your attention is something that magicians have long exploited.

So now neurologists are looking to magic to help answer questions such as:

Why don't we see always something right in front of us?

Why do our eyes more easily follow curved rather than straight gestures across space?

Magic, which has exploited such aspects of the visual for centuries, offers us a framework to explore perception in an intriguing way, and the potential for understanding our perceptual system by investigating how magic exploits its blindness and gaps is enormous.

It has become a sophisticated research method and field helping to create more intuitive human-computer interface designs and advance rehabilitation techniques for people physically impaired by neurological conditions like strokes.

It is even being used to study problems in social responsiveness across the autism spectrum.

All we need to do now is convince more magicians to give up their secrets – but how easy that will be remains to be seen.

Explore further: Barrow researchers use magic for discoveries

Related Stories

Barrow researchers use magic for discoveries

May 22, 2012
Researchers at Barrow Neurological Institute at St. Joseph's Hospital and Medical Center have unveiled how and why the public perceives some magic tricks in recent studies that could have real-world implications in military ...

Researcher finds method behind magic

May 10, 2012
(Medical Xpress) -- A magician will have the upper hand because he knows how his trick works. But, according to Jay Olson, the magician might not know why.

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

February 12, 2013
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 ...

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

March 12, 2013
A magician is using his knowledge of magic theory and practice to investigate the brain's powers of observation.

Recommended for you

New neuron-like cells allow investigation into synthesis of vital cellular components

January 22, 2018
Neuron-like cells created from a readily available cell line have allowed researchers to investigate how the human brain makes a metabolic building block essential for the survival of all living organisms. A team led by researchers ...

Finding unravels nature of cognitive inflexibility in fragile X syndrome

January 22, 2018
Mice with the genetic defect that causes fragile X syndrome (FXS) learn and remember normally, but show an inability to learn new information that contradicts what they initially learned, shows a new study by a team of neuroscientists. ...

Epilepsy linked to brain volume and thickness differences

January 22, 2018
Epilepsy is associated with thickness and volume differences in the grey matter of several brain regions, according to new research led by UCL and the Keck School of Medicine of USC.

Research reveals atomic-level changes in ALS-linked protein

January 18, 2018
For the first time, researchers have described atom-by-atom changes in a family of proteins linked to amyotrophic lateral sclerosis (ALS), a group of brain disorders known as frontotemporal dementia and degenerative diseases ...

Fragile X finding shows normal neurons that interact poorly

January 18, 2018
Neurons in mice afflicted with the genetic defect that causes Fragile X syndrome (FXS) appear similar to those in healthy mice, but these neurons fail to interact normally, resulting in the long-known cognitive impairments, ...

How your brain remembers what you had for dinner last night

January 17, 2018
Confirming earlier computational models, researchers at University of California San Diego and UC San Diego School of Medicine, with colleagues in Arizona and Louisiana, report that episodic memories are encoded in the hippocampus ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.