Category: Haptic touch

Magic without vision: Can you fool the ear like you fool the eye?

smackenz/ / Haptic touch, Hearing, Illusions, Magic tricks, Posts, Vision

Sometimes the brain gets it all wrong because it misperceives conflicting information from one or more of the senses (see our blog for Sensory illusions before and after vision). And sometimes because it is tricked by a magician. Typically, through vision.

So, are magic tricks possible without vision?

“When it comes right to it, it’s a trick for the eye. I mean, it’s a magic trick, right? So, they trick your eyes. (…) So, if you’re blind, I don’t think that’s really going to work for you. You’re never going to know what just happened. You can hear about it, but that’s not going to be a big deal for you” (according to Tommy Edison, who is born blind).

However, the brain can be tricked through the sense of touch too. For example, to feel three human fingerbones move in the palm of the hand, and two pieces of rope go straight through the neck.

“So you could show me something and show me how it changes or whatever but at any point, if I’m not touching the thing. You can just switch it just like that. And I wouldn’t know wiser” (explained by Tommy Edison, who is born blind).

But what about the other senses?

This time, Associate Professor Gustav Kuhn, University of Plymouth sheds some light on tricking the brain through the sense of hearing. Anchored in both magic and science, Gustav Kuhn has established Science of Magic, he is the Director of the MAGIC-Lab, and he is the funding member and President of The Science of Magic Association. Furthermore, Gustav has published numerous academic articles and books. And his work has been featured in the national media (e.g., by the BBC and the Guardian).

Magic is an artform that allows us to experience the impossible. At its core lies a powerful contradiction between what we see and what we believe to be possible. Most magic tricks exploit our visual perception: we see a coin vanish or a rabbit appear in a hat. But what happens when we remove sight from the equation? Can magic still work if it’s entirely auditory? And if not—why?

Investigating how magic might operate without vision offers more than practical benefits—it opens the door to fundamental questions about how different senses process information, and how much we trust each of them. For centuries, artists and scientists alike have tried to translate between the senses, asking whether sound can be “seen” or images can be “heard.” This research can support the development of sensory substitution tools—but it also highlights important limits in how different senses convey information.

Auditory-only magic tricks

In 2024, we launched a bold experiment: an international competition to create the world’s first auditory-only magic trick. The rules were strict—no visuals, no speech, no language. Just sound. Could the ear be fooled as convincingly as the eye?  Magic is full of non-verbal visual illusions—a vanishing coin, a colour-changing silk—but could pure sound evoke that same sense of wonder?

The challenge captured global attention. Magicians, sound artists, and psychologists all stepped up with creative and clever ideas. One trick stood out for its clever use of an auditory illusion. In this “trick” the magician walks around the blindfolded spectator, making a sound, and the spectator tracks their position (link to more information about the competition)—until, suddenly, the sound shifts and the magician appears to “teleport” to another spot, creating a surprising and disorienting effect. The trick was clever, but since it relied on language, it did not fully meet the competition criteria. Despite our best efforts, no submission delivered a powerful, language-free illusion. We awarded a prize for ingenuity, but the core goal remained unmet. Still, this wasn’t failure—it was insightful and what we predicted

Nearly all well-known magic tricks are visual. As a result, people with visual impairments are often excluded from fully engaging with magic performances. This isn’t just an issue of entertainment; magic can foster joy, curiosity, and even wellbeing. Ensuring access to those experiences is an important step toward inclusivity.

Both our eyes and ears are easily fooled by perceptual illusions, though we rarely notice them. For example, when listening to music on headphones, sounds can seem to come from different directions. This illusion is created by adjusting the volume and timing of sounds in each ear, and there are lots of other auditory illusions that are just as powerful as their visual counterparts. So, the rarity of auditory magic tricks isn’t due to a lack of auditory illusions.

One possibility is for the lack of auditory magic tricks is that auditory perception simply |doesn’t produce the same kind of cognitive surprise as vision. We know our ears can miss things. In the classic cocktail party effect, for instance, we often fail to notice conversations around us until we hear our name. Unlike visual failures, these auditory lapses don’t feel shocking. We accept them as normal. That means there’s less room for magic to create the emotional jolt that makes a trick truly effective. Both our eyes and ears are vulnerable to deception, but we seem to trust our vision more. When something vanishes from sight, it feels like it’s gone. But when a sound disappears, we simply assume the source has stopped making noise—not that the object has vanished. Many magic tricks revolve around manipulating physical objects—making them appear, disappear, or transform. These feats are inherently more compatible with how we interpret visual information.

The competition revealed just how much magic depends on vision, and how deeply we trust what we see compared to what we hear. In trying to trick the ear, we uncovered something fundamental about how we experience the world—and the unique role vision plays in shaping belief.

Toward a New Kind of Magic

We believe magic without sight is a frontier worth exploring—not just for theoretical insight, but for practical innovation. Developing magic for people with visual impairments is about more than accessibility; it’s about reimagining what magic can be. It invites us to consider whether the ear and other senses such as touch and smell, too, can be deceived in ways that are joyful, meaningful, and profound. To do this, we’ll need to understand how people with blindness experience magic—something that can only be achieved through close collaboration between psychologists, magicians, and individuals with visual impairments. In doing so, we not only open the world of magic to those who experience the world differently—we also expand the very boundaries of what magic, as an art and a science, can do.

Gustav has also very kindly suggested some very interesting materials for further listening, reading, and watching:

See our blog for Activities; especially 67-69.

 

Sensory illusions before and after vision

smackenz/ / Haptic touch, Hearing, Illusions, Multisensory, Vision

Sometimes the brain gets it all wrong. It misinterprets the information from one or more of the senses. This phenomenon is commonly known as sensory illusions.

Revisiting S.B., who regained his eyesight after more than 50 years of being blind. Using vision, he now recognised simple shapes and ordinary objects as well as their size. But he closed his eyes in traffic. Perhaps more complex visual information overwhelmed him. Perhaps it did not match his memories from when he was still blind. Or perhaps both. (See our blog for the scientific approach, Vision, haptic touch, and hearing and Sensory mismatch.) A related issue is that of conflicting information within and between the senses. Did S.B. show an effect on sensory illusions based on or including visual information?

When S.B. was still blind, he would have been familiar with both tactile and auditory illusions.

But what about visual illusions?

Visual experience is not necessary to show an effect on all visual illusions1. Indeed, S.B. would have encountered some of them when he was still blind. Simply because certain illusions are both visual and tactile. And S.B. would, therefore, have shown an effect on these illusions immediately after he had started using vision. For example, on the Müller-Lyer Illusion2,3.

Visual illusion: 2 lines of equal length appear unequal when the ends have arrow shapes attached.
(Müller-Lyer Illusion, retrieved from elevers.us)

The Müller-Lyer Illusion consist of two horizontal lines that are identical in length: one with inwards-pointing and one with outward-pointing fins. People who show an effect on this illusion, perceive the line with the outwards-pointing fins as longer than the other line. The Müller-Lyer Illusion is found both in people who are born fully sighted and in people who are born blind. As well as in children (born with very low or no vision; 8–16 years old) after only 48 hours of seeing4. But this was not the case for S.B., who regained his eyesight at the age of 525.

S.B. showed a very weak effect on the visual Müller-Lyer Illusion.

For other visual illusions, visual experience is sometimes necessary and sometimes not. An example is the Ponzo Illusion. The Ponzo Illusion consists of two parallel lines that are converging. These two lines are crossed by several horizontal lines that are identical in length. Almost like a railway track that disappears into the distance. People who show the Ponzo Illusion perceive the crossing lines as becoming shorter and shorter the more the vertical lines converge.

Visual Illusion, perspective of the train tracks makes the 2 yellow lines appear different sizes
(Ponzo Illusion, retrieved from illusionsindex.org)

The Ponzo Illusion does not show and effect in people who rely on their sense of touch. And prior visual experience does not change that6. This illusion is not tactile. At the same time, the visual Ponzo Illusion is found in children (born with very low or no vision; 8–16 years old) after only 48 hours of seeing4. The illusion is visual, but prior visual experience is not necessary. In a parallel vein, the Ponzo Illusion has been translated into an auditory format. This auditory version of the illusion occurs in people who are fully sighed and wearing a blindfold. But not in people who have been blind since before they were 20 months old7. The Ponzo Illusion is not auditory without prior visual experience. S.B. who had been visually impaired from before he was two years old should, therefore, have shown an effect on the visual Ponzo Illusion immediately after he had regained vision. Or on a similar illusion.

Visual illusion using perspective to make figures appear larger.
(retrieved from richardgregory.org)

Instead of judging the length of two lines as in the Ponzo Illusion, S.B. was asked to describe the relative sizes of four men. People who have been fully sighted since birth typically perceive the men as increasing in height. S.B. described: “They don’t look far away, it’s just as though the men were standing underneath (? the buildings). The first man looks smaller, but the last three look the same.” 5 S.B. showed a very weak effect on the visual Perspective Size Changes Illusion. (Gregory & Wallace, 1969, p. 22)

After having regained vision, S.B. would also encounter multisensory illusions that include visual information. These illusions consist of conflicting information from vision, touch, hearing, smell, and/or taste. The brain now has to decide how to deal with this. It most often turns to previous learning. An alternative would be to ignore the visual information. Indeed, multisensory illusions that include visual information do not exist without vision. And also not if the visual information is not associated with the other sensory information in a certain way, for example, the lip movements and the sound of spoken words. Prior visual experience is necessary.

Immediately after having regained vision, S.B. would not show an effect on multisensory illusions that included visual information. But his susceptibility to them would probably increase as he learnt to associate and integrate visual information with other sensory information. (See our blog for Crossmodal correspondences between the senses and Multisensory processing.) That is, if he did not close his eyes.

Now, challenge your senses.

Tactile illusions:

 

Auditory illusions:

 

Visual illusions:

 

See our blog for Activities; especially 65-67.

Blog post author: Dr Torø Graven

 

1. Bean, C H (1938) The blind have “optical illusions.” Journal of Experimental Psychology, 22(3), 283–289. https://doi.org/10.1037/h0061244

2. Heller, M A, … [et al.] (2002). The haptic Müller-Lyer illusion in sighted and blind people. Perception, 31(10), 1263-1274. https://doi.org/10.1068/p3340

3. Millar, S, & Al-Attar, Z (2002) The Müller-Lyer illusion in touch and vision: Implications for multisensory processes. Perception & Psychophysics 64(April), 353–365. https://doi.org/10.3758/BF03194709

4. Gandhi, T, Kali, A, Ganesh, S, & Sinha, P (2016) Immediate susceptibility to visual illusions after sight onset. Current Biology, 25(9), R358-R359. https://doi.org/10.1016/j.cub.2015.03.005

5. Gregory, R L, & Wallace, J G (1969) Recovery from Early Blindness A Case Study. Experimental Psychology Society Monograph, No. 2. https://www.richardgregory.org/papers/recovery_blind/recovery-from-early-blindness.pdf

6. Heller, M A, & Ballesteros, S (2012) Visually-impaired touch. Scholarpedia, 7(11), 8240. http://www.scholarpedia.org/article/Visually-impaired_touch

7. Renier, L, …  [et al.] (2005) The Ponzo Illusion with Auditory Substitution of Vision in Sighted and Early-Blind Subjects. Perception, 34(7), 857-867. https://doi.org/10.1068/p5219