Are you impressed with meals that look like one food but are actually made of something else? Tofu burgers and artificial crabmeat, for example, are not what they appear to be.

It's actually an old trick. In medieval times fish was cooked to imitate venison during Lent, and celebratory banquets included extravagant (and sometimes disturbing) delicacies such as meatballs made to resemble oranges, trout prepared to look like peas and shellfish made into mock viscera. Recipe books from the Middle Ages and the Renaissance also describe roasted chickens that appeared to sing, peacocks redressed in their own feathers and made to breathe fire, and a dish aptly named Trojan hog, in which a whole roasted pig was stuffed with an assortment of smaller creatures such as birds and shellfish, to the amusement and delight of cherished dinner guests.

Unwelcome visitors were also treated to illusory food, but not for their own amusement. Instead they were served perfectly good meat that was made to look rotten and writhing with worms. Maybe not good enough to eat, but good enough to send your in-laws packing!

Food illusions are alive and well in the 21st century. Our buffet of contemporary lip-smacking illusions will appeal to both your eyes and your stomach... for the most part. We hope you'll enjoy the spread. Bon appétit!

SAME BOWL OF VEGGIES... OR IS IT?
This still life by Italian painter Giuseppe Arcimboldo (left) includes the ingredients for his favorite minestrone soup and the bowl to serve it in. Turned upside down (right), Arcimboldo's bowl of vegetables becomes a whimsical portrait of a man's head, complete with bowler hat.

There are several interesting aspects to this illusion. First, why do we see a face in the arrangement, when we know that it is just a bunch of vegetables? Our brains are hardwired to detect, recognize and discern facial features and expressions using only minimal data. This ability is critical to our interactions with other people and is the reason that we perceive personality and emotion in everything from crude masks to the front end of cars.

Second, why do we see the face much more clearly when we flip the image vertically? The answer is that the same brain mechanisms that make face processing fast and effortless are optimized to process right-side-up faces, so upside-down faces are much harder to see and recognize.

A LOT TO DIGEST
Arcimboldo's composite heads demonstrate that, neuroscientifically speaking, the whole can be much more than the sum of its parts. Clever arrangements of individual fruits, flowers, legumes and roots become exquisite portraiture in their entirety, such as in the likeness of the Hapsburg emperor Rudolf II (left), here depicted as Vertumnus, the Etruscan god of transformations, or in the artist's self-portraits as Summer and Autumn (center and right).

The brain builds representations of objects from individual features, such as line segments and tiny patches of color. You see a nose in the Summer portrait not because there is a retinal cell that perceives noses but because thousands of retinal photoreceptors in your eye react to the various shades of color and luminance in that area of the painting. High-level neuronal circuits then match that information to the brain's stored template for noses. The output from those same photoreceptors also activates the high-level object-tuned neurons that recognize turnips, figs and pickles, which is what makes images like these so much fun to look at.

Last but not least, Arcimboldo's masterpieces also bring to mind the old adage that you are what you eat. “Avoid fruits and nuts,” advises Garfield, the cartoon cat created by Jim Davis.

HUMMINGBIRD FOOD
The human brain simultaneously recognizes animal features (such as eyes, wings and tail) and plant parts (such as an eggplant and artichoke leaves). The combination tickles our fancy.

MEDUSA MARINARA
Brazilian-born artist Vik Muniz likes to play with his food. His Medusa Marinara (far right) is a visual pun on Caravaggio's Medusa (right), and it portrays an illusion of ambiguity that works at multiple levels. The red marinara sauce in Muniz's Medusa reminds the viewer of the blood spurting from Medusa's severed neck in Caravaggio's version, and the spaghetti around Medusa's head can be perceived as Caravaggio's snakes-for-hair Medusa (an ambiguity illusion in and of itself).

FOODSCAPES
Art can be more than just a feast for your eyes. The image at the left looks, at first sight, like a painting of a landscape. But look closer. These are actual photographs of foods laid out to re-create various types of scenery and terrain. London photographer Carl Warner (top right) arranges meats and vegetables to create each environment as if from a Brothers Grimm fairy tale and then photographs the scene in layers from foreground to background.

By using solely meats and breads in the image at the bottom right, for example, Warner captures the feel of old sepia postcards from the late 19th-century American prairie—complete with a breadstick-rail fence, serrano ham skies and a salami lane. Yum.

Warner's work is another example of how the brain puts together information from multiple streams. Visual data from every point of the image are converted from light to electrochemical signals in the retina and then transmitted to the brain—where individual features are constructed from the information in the image. These discrete features are broadcast to multiple high-level visual circuits simultaneously: circuits that recognize faces, circuits that detect and characterize motion, circuits that recognize landscapes and places, and circuits that recognize and process food are just a few of the brain paths that receive this basic information.

In Warner's art, both the landscape and the food-processing circuits are activated (the other circuits receive the information but ignore it as irrelevant because there are no faces, motion or other triggers in the image). And voilà! Our mind recognizes a delicious plate of cold cuts, as well as an overcast sky, in the same visual data.

CHICKEN AND EGG
Spanish artist Din Matamoro provides a unique perspective on developmental biology's most fundamental question: Which came first, the chicken or the egg? In Matamoro's fried eggs, ontogeny recapitulates phylogeny in an unusual and slightly unsettling fashion: the shape of each fried egg resembles that of the chicken that the egg would have become or perhaps the hen that laid the egg in the first place.

Such ambiguity illusions recapitulate visual perception as a type of ontogeny in and of itself. Objects, in this case chickens, are built in the henhouses of our mind from nuggets of visual information sent from the retina. These little visual giblets activate circuits that process animal shapes (birds in this case) as well as circuits that process food data. This kind of multiple-channel processing is at the heart of all ambiguity: the neural basis of ambiguous perception is two or more brain circuits that compete for dominance in our awareness.

EDIBLE POINTILLISM
Pointillist painters such as Georges Seurat and Paul Signac juxtaposed multiple individual points to create color blends that were very different from the colors in the original dots. But in a very real sense, all art is pointillism. In fact, all visual perception is pointillism. Our retinas are sheets of photoreceptors, each sampling a finite circular area of visual space. Every photoreceptor then connects to downstream neural circuits that build our perception of objects, faces, loved ones and everything else. Thus, vision itself is largely a pointillist illusion, colored by a tremendous amount of “guesstimation” and filling in on the part of our brain. It doesn't matter whether the painter uses brushstrokes or fields of dots to define surfaces.

The dots that compose these images of a cherry-topped cupcake (left) and Laurel and Hardy (right) are made from multicolored jelly beans, a technique that is not only clever but also delicious. Eat your heart out, Seurat.

MOUTH-WATERING MASTERPIECES
If you agree that jelly-bean pointillism is a great idea, you'll also appreciate these replicas of famous masterpieces: Vincent Van Gogh's Self Portrait in a Grey Felt Hat (left), Edvard Munch's The Scream (below left) and Rembrandt's The Anatomy Lesson of Dr. Nicolaes Tulp (below right). Everything in the accompanying images is fit for human consumption.

FOOD ART WITH LITTLE PEOPLE
Dramatist George Bernard Shaw said that there is no sincerer love than the love of food. If so, the miniature workers depicted here are living the dream. Of course, it's all a matter of scale.

The juxtaposition of Lilliputians and huge fruit has the dual illusory effect of making the potentially normal-size people look tiny and the possibly typical fruit look supersized. It happens because the human brain uses context, the relative dimensions of nearby objects in the world as a primary means to determine their scale and absolute size.

Think about it: we can't simply use the size of the projection on our retinas to determine the size of an object, because the size of the projection depends on how far away the object is. A small, nearby object can have a retinal projection of the same size as a larger object that is farther away. To compensate for distance, the brain compares the sizes of unknown objects with those of known objects that are in the same scene. Juxtaposing tiny people with enormous fruit plays havoc with that scaling system, and both categories of object are affected.

A SMORGASBORD OF ILLUSIONS
Peeling and paring can transform fruits and vegetables into a variety of amazing, strange and tasty illusions. Just in case your eyes are bigger than your stomach.