Troxler Effect Explained
Troxler effect, or Troxler fading, refers to visual perception fading based on repeated exposure to the same stimulus. The phenomenon was named after Swiss ophthalmologist Ignaz Paul Vital Troxler, who discovered it in 1804.
What is the Troxler Effect?
The Troxler effect is a phenomenon of visual perception that can cause an image to disappear or alter. In technical terms, Troxler fading is the apparent reduction or elimination of a visual stimulus when gazed at fixedly but covertly. The Toxler effect is named after Swiss physician and physicist Franz Carl Simon Troxler (1755–1834). It was later discovered independently by John Graham Brown in Scotland in 1872. To best understand how it works, imagine that you are looking at a square for about five seconds.
Two types of Troxler fading.
- Accommodative
- Peripheral fading.
Accommodative fading
Accommodative fading occurs when you focus your eyes on something and then look away and find it difficult to see again; peripheral fading occurs when your gaze moves to one side so that you lose your ability to see from the opposite eye.
As we age, our eyes' lenses naturally become less flexible. This makes it harder to focus on close objects—like a book or tablet—but as soon as we look away, things in our peripheral vision come into focus. This phenomenon is called accommodative fading, and it's caused by presbyopia, a condition that affects nearly everyone over 40. Luckily, prescription reading glasses can correct presbyopia so you can see more clearly when reading documents up close. Another option is bifocals with progressive lenses that eliminate distance blur while also allowing you to see items clearly in your periphery.
As we age, our eyes' lenses naturally become less flexible. This makes it harder to focus on close objects—like a book or tablet—but as soon as we look away, things in our peripheral vision come into focus. This phenomenon is called accommodative fading, and it's caused by presbyopia, a condition that affects nearly everyone over 40. Luckily, prescription reading glasses can correct presbyopia so you can see more clearly when reading documents up close. Another option is bifocals with progressive lenses that eliminate distance blur while also allowing you to see items clearly in your periphery.
Peripheral fading
The Troxler effect, also known as central fading, is a visual phenomenon first described by Swiss physician Ignaz Paul Vital Troxler in 1804. The most common variant of it is peripheral fading, which is when an object appears to fade because of eye movements. The viewer will see an object and look away quickly. When they look back, there will be less color contrast (if any) between a colored figure and its background; therefore, you can't see it as well because it has faded into them. This effect does not actually occur in nature -- it's something that your brain does.
How does the Troxler effect work
People who hear colors or see sounds are not necessarily off their rockers. In fact, they might be right, and it's a science that backs them up. The Troxler effect is a cognitive phenomenon in which someone's perception of an object changes due to their previous exposure to a different image. When people concentrate on a visual task with one eye, there is less visual information coming into their brain from that eye, resulting in slower reaction times for those images in future tasks and recall tests compared to other objects that were never shown before.
When Can I Expect to See the Phenomenon?
As a simple experiment, look at your TV screen from a few feet away. Without changing anything, stare at it for about half an hour. If you look away for just one minute and then glance back, you'll notice that something is slightly different than when you left off. It's called the Troxler effect (also known as Troxler's fading), and it was first discovered by Ignaz Paul Vital Troxler in 1804. Before we get into what exactly causes that slight difference, let's quickly discuss why we see that slight change to begin with.
How to See it
The Troxler effect is a phenomenon in which when a certain stimulus is presented to vision, and that stimulus is removed, people's visual system memorizes it. This memory causes people to actually perceive a fading afterimage of it. In other words, if you stare at something for long enough without looking away, then look away and try to see it in your peripheral vision or against another image, you will be able to see it there as if it were still being presented! The concept can be applied for paranormal research or enhancing psychology illusions with afterimages.
The best way to understand Troxler's effect is by trying it yourself. Take a look at an object in your periphery, then turn away and close your eyes. Notice how it disappears? Yep—the brain filters out what you can't see so that you can focus on what you are looking at. It's a subconscious mechanism most of us aren't even aware of, but it also happens when we weblink. Just as with blinking, there are ways to train your brain to slow down its Troxler effect response time. If you have a sensitive vision or have struggled with your eyesight in recent years, start practicing consciously holding your gaze without blinking.
The best way to understand Troxler's effect is by trying it yourself. Take a look at an object in your periphery, then turn away and close your eyes. Notice how it disappears? Yep—the brain filters out what you can't see so that you can focus on what you are looking at. It's a subconscious mechanism most of us aren't even aware of, but it also happens when we weblink. Just as with blinking, there are ways to train your brain to slow down its Troxler effect response time. If you have a sensitive vision or have struggled with your eyesight in recent years, start practicing consciously holding your gaze without blinking.
How can you use it
The Troxler effect is a phenomenon in which when a certain stimulus is presented to vision, and that stimulus is removed, people's visual system memorizes it. This memory causes people to actually perceive a fading afterimage of it. In other words, if you stare at something for long enough without looking away, then look away and try to see it in your peripheral vision or against another image, you will be able to see it there as if it were still being presented! The concept can be applied for paranormal research or enhancing psychology illusions with afterimages.
The Troxler effect is quite simple to grasp. You just need to understand that your vision is actually sensitive to stimuli within your visual field, not just images in front of you. So, if you are focusing on a certain image and someone moves it (or brings in another image), your brain will see that change because your eyes aren't really focused on what they're looking at. In other words, vision works from an area around us, not from our point of focus. This makes sense, but it isn't something we usually think about when we look at objects.
The Troxler effect is quite simple to grasp. You just need to understand that your vision is actually sensitive to stimuli within your visual field, not just images in front of you. So, if you are focusing on a certain image and someone moves it (or brings in another image), your brain will see that change because your eyes aren't really focused on what they're looking at. In other words, vision works from an area around us, not from our point of focus. This makes sense, but it isn't something we usually think about when we look at objects.
How to do the Troxler effect mirror
The next time you're waiting at a grocery store, sit down and watch people walk by. Eventually, you will stop seeing them as individuals, but a floating mass of faces that all look slightly different. This is an example of something called the Troxler effect or fading affect bias. The Troxler effect is a visual phenomenon where we fail to notice repeated images in our peripheral vision because our brain is so good at glossing over what it considers unimportant details.
First, find a mirror and stand in front of it. Next, draw an imaginary line dividing your reflection into two segments. Focus on a particular item of clothing or jewelry you're wearing on one side of your body and stare at it for a few seconds. Then, without moving your head, look straight ahead and try to notice small differences in your reflection that can serve as indications that you've done The Troxler Effect correctly. For example, suppose you have earrings on one side of your body and cross earrings on the other. In that case, you might see them switch sides after doing The Troxler Effect properly.
First, find a mirror and stand in front of it. Next, draw an imaginary line dividing your reflection into two segments. Focus on a particular item of clothing or jewelry you're wearing on one side of your body and stare at it for a few seconds. Then, without moving your head, look straight ahead and try to notice small differences in your reflection that can serve as indications that you've done The Troxler Effect correctly. For example, suppose you have earrings on one side of your body and cross earrings on the other. In that case, you might see them switch sides after doing The Troxler Effect properly.