Celeste McCollough Howard, an American psychologist, was born in 1927. Throughout her career, she accomplished great feats. Out of all the feats she gained acclamation for, the McCollough effect was one of her greatest accomplishments. How did she come to discover the McCollough effect? For that, we have to look at how she arrived at it by going back to the beginning. 

Celeste McCollough:  Her Journey to become One of the Best 
Celeste McCollough was a driven and smart woman that wanted to excel at everything she put her mind to. Her knowledge of psychology led her to share it with others who had the same passion for the subject so she began to teach at Olivet College in Michigan.

After teaching from 1954-1956 at Olivet, Oberlin College awarded her with a full-time teaching position in the Department of Psychology, making her the first woman to join it. For research purposes, she left the college to visit Canada to research about perceptual effects of wearing glasses tinted with two colors. Her discovery became known as the McCollough effect.

What is the McCollough effect? 
The McCollough effect is a visual phenomenon where a person perceives colorless gratings as colored.  The person’s perception depends on the orientation and contingent of the gratings. In order to produce the effect, a person needs to be induced to see it. 

For instance, you look at a red vertical grating and a green horizontal grating for a few minutes, going back and forth between them. After a while, a black and white vertical grating will appear pinkish. For this reason, the effect has come to be known as one of the most remarkable effects to date.

The Popularity of the Effect Explained 
The McCollough effect is regarded as one of the most amazing illusions because its effects last for a long time. The effects might last for an hour or more, depending on the length of time you stare at it. In 1975, scientists, Holding and Jones, discovered that fifteen minutes of induction could increase the strength of the effect by three months. Furthermore, do not confuse the effect with colored afterimages, as both are two different phenomenons. 

Colored afterimages are superimposed and do not last a long time, whereas the McCollough effect does not do either of these. One thing in common between the two is that both require a period of induction to work. Due to the long duration of the effect lasting, scientists went into hysteria to find out how the effect was produced.

How the Effect Functions? 
With hundreds of explanations being thrown around about the McCollough effect, people narrowed down the barrage of explanations, saying that it was due to the sensitive neurons in lower monocular regions of the visual cortex. Additionally, another phenomenon came into existence, which was the anti-McCollough effect. 

Alternating pairs of grating in parallel alignment, one black and white and a single color either red or black induce the anti-McCollough effect. The perceived shade is the same as the inducer shade and the effect is weaker.

We bet you are now curious to try the McCollough effect, but do not stare at it too long, as you know what happens if you do.

Zoetrope is a type of pre-film animation device that creates the illusion of movement by producing a series of pictures or drawings to show progressive phases of a particular motion. The Zoetrope is made up of a cylinder with vertical cuts at the sides. When you look inside of the zoetrope, you will see a band with pictures from a set of pictures aligned in sequence.

The cylinder has to spin in order for the user to see the pictures move through the slits. Without the slits, the picture will blur together, preventing the user from seeing the picture clearly. With the slits, the user is able to see the images move when in fact, what they are actually seeing is an illusion of movement.

These types of devices have been in development since the 20th century such as 3D zoetropes and linear zoetropes. The type of zoetrope that will be discussed in detail is called the cylindrical zoetropes.

A Look Back in the History of the Zoetropes

Ding Huan, a Chinese inventor, invented a device called “a variety of zoetrope” in 100 BC. The function of this device remains unknown to this day. All people know is that something along the lines of moving pictures was invented. Next, came the British’s turn to invent something similar, which they accomplished in 1833 or 1834.

This time it was William George Horner, a British mathematician, who developed a drum-like shape of the zoetrope. By the time he came around to building it, he had prior knowledge of the phenakistoscope disc.

Horner’s version contained rotating discs with slits to view the pictures. He ended up calling his invention the daedaleum. His invention did not become a huge hit until the 1860s when an alternation to the device was made; allowing people replace the pictures with new ones. Milton Bradely, an English inventor, and William F. Lincoln, an American inventor, both filed a patent for it. The American inventor called his device zoetrope, which became an instant hit.

© opticalspy 2015 - Image sources unknown

At a young age, D.L. "Rusty" Rust was inspired to become one of the most accomplished artists in the United States. If someone asked what he wanted to be when he grew up, he was quick to reply—an artist. 

Born in Erie, Pennsylvania, Rusty influenced by the work of his grandfather, Emil Rust, received his grandfather’s ability and passion to draw and create work of art to impact people in a meaningful way. 

What better way is there to impact people than creating illusions? The artist in him recognized that. Therefore, he combined his passion for creating wildlife art and optical illusions, using oil on canvas to produce art that would resonate with viewers. 

The Wild Life of Rusty 
Growing up in Erie, Pennsylvania, Rusty was exposed to the wonders of outdoors—the beaver ponds, creeks, fishes, birds, grasslands, trees, swamps, and more. Wanting to incorporate the surroundings of the place he grew up in came naturally to him. 

The works of his grandfather and other artists such as Gil Elvgren, Norman Rockwell, and Bob Toombs also helped mold his work to what it is today. In fact, in his earlier paintings, you can see the influence of other artists, which he proudly claims to be one of his greatest assets in his growth as an artist. However, before he began to create wildlife, he painted circus and portraits, but since then he shifted his focus to reproduce nature in all of its glory. So far, his impressive resume includes wildlife, seascapes, illustrations, camouflage-type, pin-up, fantasy, still life, glamour, portraits, and nude paintings. 

You can revisit his earlier work, which is on display at the Ringling Museum of Circus in Sarasota, Florida, the National Portrait Gallery of the Smithsonian Institute in Washington, D.C., and the Norman Rockwell Museum in Philadelphia, Pennsylvania. 

If you would like to see more of Rusty's work take a look at our Donald Rust Gallery.

The Mystery of the Third Phoneme 
The psychologist explained the existence of the third sound by demonstrating the relationship between the visual component and the sound when paired with each other. In order to gain a better understanding, let’s break down to you the three sounds watching the video produced:

1. Watching the video with sound and eyes open will produce a “da da da” sound.
   
2. Watching the video with sound and your eyes closed will produce a “ba ba ba” sound.
   
3. Watching the video without sound and your eyes open will produce a “ga ga ga” sound.
   

In short, the McGurk Effect proved that your senses didn’t evolve in isolation from one and other, but they actually work in union with each other to assist people perceive the world around them. When more than one sense is stimulated at the same time with each other, it enables the brain to learn and remember the information better. However, not everyone is susceptible to the McGurk effect, as different factors such as brain damage and certain disorders can influence a person’s perception. 

List of Disorders 
People with the following disorders have shown little to zero impact when exposed to the McGurk effect:

• Dyslexia-  Cannot perceive and produce consonant clusters
  
• Language Impairment- Children utilize less visual information in speech perception, but can perceive auditory cues only
  
• Autism Spectrum Disorder- Cannot identify visual and auditory aspects of speech
  
• Language Learning Disabilities- People with underdeveloped language skills
  
• Alzheimer’s Disease- Loss of memory leads to decreased influence on the visual stimulus
  
• Schizophrenia- Decreases the development of audiovisual integration
  
• Aphasia- Impaired  visual, auditory, and audio with visual condition
  

Apart from these disorders, other factors that hinder the effect of the McGurk effect include cross-dubbing, mouth visibility, and syllable structure, amongst others. The McGurk effect isn’t magic, but its unearthing led people to discover how people’s senses depend on one another, thus heightening the importance of sight and hearing. 

Oleg Shuplyak:  The Master of Faces 
Oleg Shuplyak, a student of architecture, was born in the Ukraine on September 23, 1967. He enrolled at the Lviv Polytechnic Institute to study architecture, which was secondary to his first love—painting. It was at the institute where he learned to compose pictures and articulately position images inside it. 

In his free time, he began to create oil paintings, drawing famous faces inside it. His unique approach branded him as one of the most accomplished and famous illusionists of our time. 

The Hidden Secrets of Shuplyak’s Oil Paintings 
Do you wonder what went through Shuplyak’s mind when he first sat down to create his very first oil painting? Did the idea of creating a second layer on top of the first just come to him one day? Who knows! All we know is that he gave us mesmerizing optical illusions that play with our minds. 

His brilliance in creating not one, but two pictures is astounding. It is as if he has created a two in one oil painting. The artist is well known for placing a second image behind the characters, objects, coloring, and objects of the first image. From the first image, protrudes a second image of famous people such as Zeus, Uncle Sam, Charles Darwin, John Lennon, and more. The conniving artist loves to play with the viewer’s mind, confusing them further.

All paintings are shown with the kind permission of the artist.

Shuplyak’s Mind Tricks 
In some of his oil paintings, the second image is clearly visible. It is so visible that the first image gets lost, which results in the viewers trying to place the first image in their mind. The artist really befuddles with our minds with his unique conception of images. In the instance the second image is not visible, squint your eyes and move back until you can see it. Shuplyak’s oil paintings truly trick the mind, if you would like to a lot more of Oleg's work click through to our Oleg Shuplyak Gallery.

© opticalspy 2015

You must have come across different kinds of visual effects over the internet. Ever seen one where you are required to stare at some moving optical illusion for a while and then stare at a blank wall and you notice that something is moving on the wall too? This is known as the motion aftereffects. It’s an illusion that your mind creates where you are able to see movement when in reality there is none. Still don’t understand how this happens? Let’s start from the very beginning.

What is Motion Aftereffect? 
Also known as the waterfall illusion, the motion aftereffect or MAE occurs because of motion adaptation. This means that your brain basically captures the effect of the moving body and then projects that image on a blank, unmoving object. Your brain is made up of many neurons. What happens is that they adopt the activity of an object in order for you to understand what is happening. When you continue to focus on the same activity for some time, say 60 second, the neurons adopt this activity. So when you suddenly move your gaze from the moving effect to a still effect, the neurons in action are the ones which were in motion. Hence, the object you are focusing on now also seems to be in motion. This effect lasts for a few seconds before the neurons for stationary object come alive.

In very simple words, when you look at a waterfall for some time and then switch your gaze to the rocks right next to it, it will feel like the rocks are moving too. But the most interesting thing about the whole scenario is that, unlike the waterfall which was moving in a downward direction, the rocks will seem to be moving upwards. This is what happens in the motion aftereffect, where you see motion in a stationary object, but it is reversed.   

A Brief History    
Research suggests that the motion aftereffect has been known since the time of the Ancient Greeks. Aristotle in 350 B.C. explained the effect once he continued to look at a moving object. But he did not distinguish the direction of the motion. But it was in 1820 that the first clear basis of motion aftereffect was laid by Jan Evangelista Purkyne, a physiologist and anatomist from Czech Republic. He gave the theory after checking out the movement of the cavalry parade. In 1834, Robert Adams came up with the term ‘waterfall illusion’ when he went to visit the Fall of Foyers in Scotland that is located near the Loch Ness. He was the one who explained how after looking at the moving water of the waterfall, it felt like the stones next to it were also moving.

Other scientitsts who tried to explain and understand the concept of motion aftereffect include Thompson (1880), and Gustav Adolf Wohlgemuth (1911).

Now the next time you look at such an illusion, you will be able to understand the science behind it too!   

Camera obscura is a Latin word for “dark chamber.” Without camera obscura, photography and the invention of the camera would not have been possible. Imagine a world without selfies or photos of landscape, animals, and people. The thought only sends shivers down our spines! Fortunately, the invention of the optical device known as camera obscura was made possible in ancient times. The concept of optical projections was very much a reality in Aristotle’s era. However, the first mention of the camera obscura was in the 5th century BC.

The History of the Camera Obscura 
Mo-Ti, a Chinese philosopher, living in the 5th century BC mentioned a device that could invert images created by rays of light travelling through a pinhole into a dark room. He referred the dark room as the “locked treasure room” or a “collecting phase.” The next mention of the optical device happened in 384 to 322 BC by the one and only Aristotle, an acclaimed Greek philosopher.

Aristotle perceived the optical device as a technique for partially exposing the sun onto the ground through the holes created in the sieve. During the time, no one had thought to perform experiments using the optical device, or made remarks on it by the given information on hand. Alhazen saw an opportunity here. Alhazen was an Islamic scholar and scientists in 965 to 1039 AD. He performed experiments that included the positioning of five lanterns outside of an area with a hole. In 1490, 


it was Leonardo Da Vinci’s turn to make his own clarification of what the camera obscura is. In his notebooks, he began to describe the characteristics of the camera obscura. By now, people knew the function of the camera obscura and on how it allowed people to capture images. The next step was to improve the quality of the pictures taken.

The Improvements made to the Camera Obscura 
Light goes through a straight line, reflecting the rays from a bright object, which passes through a hole. In doing so, it reforms the object into an upside down picture on a flat surface, which is held parallel to the hole. The process was improved in the 16th century by adding a convex lens inside the aperture and later a mirror to reproduce the image down or up onto a surface. 

Due to improvements made to the device, it gained notoriety amongst artists in 1558, especially from Magia Naturalis, which recommended artists to use the optical device to assist them to draw images. Nowadays, camera obscura is extinct and referred to as a pricy antique if obtained. 

One thing for sure, this ancient optical device left behind a legacy for future innovators to refer to, which they did, when cameras were introduced. Since then, the world has seen other magnificent inventions that assist people capture the beauty of life through a lens in day light, without the help of a dark room to do it. 

It has been proposed by some that a number of famous artists from the past used camera obscuras or other optical techniques to produce their photo realistic masterpieces. This theory is discussed and duplicated in the excellent documentary Tim's Vermeer, it really is worth a look.

In Snow White, the step-mother was green with envy at seeing the beauty of her step daughter. She couldn’t handle being the second to her, as for her, life was a beauty contest, and she needed to stay number one. When Snow White blossomed into a beautiful girl, she became jealous, but didn’t react. When the mirror pronounced Snow White as the most beautiful girl in the land, the queen plotted her murder.

Although everything worked out in the end, the message of the store was clear. Vanity is not a good trait to have, yet people these days are transfixed at beautifying themselves to feed their vanity. Vanity was the inspiration behind the late Charles Allan Gilbert’s illusion called “All is Vanity.”

The Inspiration behind “All is Vanity” Illusion 
Charles Allen Gilbert was born on September 3, 1873 and passed away on April 20, 1929. He lived a prosperous life where his work was often used as an example to show people the art of creating illusions. One of his widely praised illusion is “All is Vanity.” The idea to create the illusion after he began to read the biblical verse, “Vanity of vanities, saith the Preacher, vanity of vanities; all is vanity,” which refers to the pride and vanity of a man.

However, in the world of art, vanity refers to women preoccupied with preserving her beauty. After reading the biblical verse and taking into account art’s representation of a woman, he created the “All is Vanity” illusion.

What is the “All is Vanity” Illusion? 
The “All is Vanity” illusion features a woman sitting behind a vanity mirror looking at her image, but there is more to the picture than just a woman and her vanity mirror. The artist drew a human skull, which serves as the focal point to place the vanity mirror in.

The skull in the picture represents the phrase “remember you will die,” reminding people that no one lives forever. The concept of the illusion is quite scary, as it sends a message to people that vanity shouldn’t be relegated as the most important thing in your life, as in the end, everyone looks the same — the skull.

The message of the illusion really spoke to people and was published in magazines, newspapers, and everywhere on the internet. Even today, the illusion resonates with people, reminding them of how vanity and pride are two traits that are still very much alive in today’s modern culture.

With the invention of Photoshop, camera filters, and apps that make you look beautiful by erasing all your perfections are readily downloaded. Most people are still occupied about taking the perfect “selfie” for instance, whereas magazines retouch pictures of celebrities to enhance their beauty. Instead, people shouldn’t be too concerned about perfecting their outside, but should try to perfect their inner beauty. So, the message behind Charles Allen Gilbert illusion called “All is Vanity” falls upon deaf ears, as it’s admired for its beauty and not its message. 

You may also be interested to see our Tom French gallery. Tom's work includes lots of Skull illusions.

Optical illusions, one of mankind’s gifts to us, dates back to the 5th century B.C. It was a time of discovery where the surroundings where still viewed as a mystery, waiting to be solved. One mystery was of the unexplainable optical illusions that existed during that time. Epicharmus, a Greek philosopher, was the first one to provide an answer for it.

Epicharmus explained how our sensory organs are responsible for the deception, which caused people to see more than just an ordinary picture. Later, Protagoras, another Greek philosopher, drew his own conclusions, coming up with an entirely new reasoning on the matter. Protagoras blamed the environment for the distorted view and not the senses.

With two starkly different views deduced by that century’s most acclaimed philosophers, people did not know whose explanation to believe. Now, it was up to Aristotle, a notable Greek philosopher, to assess both deductions and decide on the most plausible answer.

Aristotle’s View of the Different Theories 
However, Aristotle was just as confused as everyone else, as he believed that both philosophers were right, but to a certain degree. He agreed with Protagoras’s assumption that people need to rely on their senses to receive a correct image of reality. Later, he added that people’s five senses could easily be fooled into believing something that wasn’t there.

Still, the concept of optical illusions wasn’t clear and the debate on them continued. Several different researchers and philosophers began to ponder over the answer to the mystery of optical illusions. One of the philosophers that became fascinated with optical illusion was Plato.

Plato, a Greek philosopher, said that the trickery and the reality of the optical illusions were due to both the mind and the senses. Since then, other notable personalities studied the mystery behind the optical illusion.  They are:

1.     Johannes Mueller and J.J. Oppel
Psychologists In the 19th century, Muller and Oppel performed various studies related to finding out of how people perceive optical illusions. They published several articles and wrote numerous books, which reignited people’s interest in optical illusions. Both of them proposed twelve theories, explaining the unexplainable phenomenon.

2.     Hermann von Helmholtz
German Physicist In the 19th century, Hermann von Helmholtz provided people with the concept of cognitive illusion. He was in agreement with Protagoras, as according to him, the assumptions people hold about their environment as a whole trigger cognitive illusion. For instance, the Café Wall illusion is an example of cognitive illusion.

3.     W.E. Hill, Illustrator In 1915
W.E. Hill developed a cartoon of a young and an old woman merged together. Some people saw an old woman whereas others saw a young woman. The explanation of how this optical illusion was created was due to individual perceptions of it.

4.     The Rise of Op Art 
In the 60s, artists such as Vasarely and Bridget Riley developed an interest in Op Art, painting abstract images. They painted vibrations, hidden images, flashing, and other abstract patterns. 

Optical illusions have an illustrious history that begun with the Greek philosophers and made a lasting impression on painters, psychologists, illustrators, researchers, and us. 

© opticalspy 2015