Opponent Process Theory Of Color Vision

Opponent Process Theory Of Color Vision

Opponent Process Theory: Opponent-process theory is a psychological and neurological model that accounts for a wide range of managements, including color vision. This model was first urged in 1878 by Ewald Hering, a German physiologist, and later expanded by Richard Solomon, a 20th-century therapist. American psychologist Benjamin Avendano contributed to this model, by adding a two-factor model.

The opponent process theory of color vision suggests that our ability to perceive color is controlled by three receptor compound with opposing actions. These three receptor compound are the red-green compound , the blue-yellow complex, and the black-white complex.

Opponent Process Theory Of Color Vision

According to the opponent process theory, these cells can only detect the presence of one color at a time because the two colors face one another. You do not see greenish-red because the enemy cells can only detect one of these colors at a time.

Opponent-process Theory

The opponent process theory suggests that the way humans perceive colors is controlled by three rules systems. We need four unique colors to represent concept of color: blue, yellow, red, and green. Conferring to this theory, there are three opposing channels in our vision. They are:

  • blue versus yellow
  • red versus green
  • black versus white

We perceive a hue based on up to two colors at a time, but we can only detect one of the facing colors at a time. The opponent process theory proposes that one member of the color pair suppresses the other color. For example, we do see yellowish-greens and reddish-yellows, but we never see reddish-green or yellowish-blue color hues.

The theory was first proposed by German physiologist Ewald Hering in the late 1800s. Hering disagreed with the getting theory of his time, known as the trivariance of vision theory or trichromatic theory, put forth by Hermann von Helmholtz. This theory proposed that color vision is based on three primary colors: red, green, and blue. Instead, Hering believed that the way we watch colors is based on a system of opposing colors.

As mentioned above, Hering’s opponent process theory clashed with the trichromatic theory that controlled his time. In fact, Hering was known to strongly oppose von Helmholtz’s theory. So which is correct?

It turns out that both of these theories are required to fully describe the intricacies of human color vision.

The trichromatic theory helps to explain how each type of cone receptor detects different wavelengths in light. On the other hand, the enemy process theory helps explain how these conoids connect to the nerve cells that determine how we actually perceive a color in our brain.

In other words, the trichromatic theory reads how color vision happens at the receptors, while opponent process theory interprets how color vision occurs at a neural level.

While the trichromatic theory makes clear some of the cases involved in how we see color, it does not explain all aspects of color vision. The opponent process theory of color vision was promoted by Ewald Hering, who noted that there are some color junction that people simply never see.

For example, while we often see greenish-blue or blueish-reds, we do not see reddish-green or yellowish-blue. Opponent process theory suggests that color perception is controlled by the activity of two opponent systems: a blue-yellow mechanism and a red-green mechanism.

Opponent Process Theory Of Color Vision

Opponent Process Theory Of Color Vision

In 1874, a German physiologist researching the functions of the eye named Ewald Hering noticed that there are certain color junction that are never seen, such as reddish-green or bluish-yellow. From this observation, he proposed opponent-process theory, which states that we perceive color in terms of opposite ends of the spectrum: red to terrace, yellow to blue, and white to black.

It is through this theory that we can explain afterimages, or when we keep seeing the same image after it’s vanished. For example, if you stare at something red for a minute then avert your eyes toward a white surface then you will see a green afterimage. If you stare at a blue circle you will see a yellow eyesight, and if you stare at a white dot you will see a black afterimage.

You can see this more clearly from the picture here.

How Opponent-Process Theory WorksStare at the white dot in the middle of the flag for about a minute. Afterwards, move your eyes to a white surface. You should see an afterimage of the flag in the colors of red, white, and blue so that it looks like the actual American flag.

While other theories of color vision explain how color is processed by the eye, opponent-process theory explains how it is processed by the brain. Once information about color is detected by the retina, or the membrane in the back of the eye, that information is sent to an area of the brain called the thalamus. The thalamus is responsible for receiving all the information from the sensory organs (eyes, ears, etc.) and forwarding that information to the correct part of the brain that processes it. In this case, the thalamus sends visual information to the visual cortex of the brain. Within the thalamus, there is a cluster of brain cells referred to as the lateral geniculate nucleus (LGN), which is responsible for the opponent-processing of colors and the afterimage effect.

Color Vision Theories

Color doesn’t exist. Not really. Right now you’re probably thinking something along the lines of: ”well, I can see color.” This will lead you to one of two conclusions. Either I’m crazy, or you are incredibly special. Actually, there’s more at work here than that. What we perceive as colors are light waves of different frequencies that bounce off of objects, enter specific receptors in our eyes, are translated into an electric signal, enter our brains, and are translated as color. It’s a complex process, and scientists have developed a number of theories to explain how it works. One of these models is called the opponent-process theory.

The Trichromatic Theory

The opponent-process theory, developed by Ewald Hering, is one of the two basic models explaining how we see color. But to understand it, we have to talk about the other model first. The trichromatic theory basically states that in our eyes there are three kinds of photoreceptors called cones. Some cones can only receive light waves of short frequencies, resulting in the color blue. Others can only receive medium waves, resulting in green, and the others can only receive long waves, resulting in red. So, blue, green, and red cones receive light of different wavelengths and translate them into signals the brain can understand as color.

The trichromatic theory is very popular, but it doesn’t seem to explain everything. Enter the opponent-process theory. This model describes the relationship between the cones to explain how they form a spectrum of colors. The basic idea is that cones are linked together in opposing pairs. Only one cone in each pair can create a signal for the brain at a time. Let me ask you this: have you ever seen a color that wasn’t quite blue, but wasn’t quite green–a bluish-green? Sure you have. That’s because the cones for blue and green are not opposing pairs. They are able to fire at the same time. However, have you ever seen a color that’s sort of yellow and sort of blue? No, there is no yellow-blue, just as there is no reddish green. Red and green are opposing pairs. Only one of them can be firing at a time. You can see blue and red together, or blue and green together, but not green and red.

The Opponent-Process Theory

This theory also explains how we can see the color yellow. Yellow is a primary color, meaning it is not composed of any other combined colors. So how can we see it if there is no cone for yellow? Yellow is the opposing pair of blue, so as long as the blue cone is active, the red and green cones cannot send signals to the brain that can be translated as yellow. However, when the blue cone is inactive, the red and green cones can receive yellow light (which has a medium-long wave length) and transmit that signal. But the minute blue comes back on, this is inhibited. You can only see blue or yellow in a single spot. They can be next to each other, but not overlapping or mixing. In a similar way, the balance of signals between all three cones produces the colors of black or white, but never both simultaneously. Thus, our three opposing pairs are red-greenblue-yellow, and black-white.

What is the opponent process theory of color vision?

Developed by Ewald Hering(1920/1964), the opponentprocess theory states that the cone photoreceptors are linked together to form three opposing colour pairs: blue/yellow, red/green, and black/white. Activation of one member of the pair inhibits activity in the other.

What is the opponent process theory of motivation?

Opponent Process Theory Definition

Richard L. Solomon’s opponent process theory of emotions—also commonly referred to as the opponent process theory of acquired motivation—contends that the primary or initial reaction to an emotional event (State A) will be followed by an opposite secondary emotional state (State B).

How do the trichromatic theory and opponent process theory explain color vision?

Trichromatic theory is that our eye detects with red, green and blue receptors and process these to perceive colour. Opponentprocess theory is that we have a colour receptors and opposing colour receptors and perceive that colour by the balance between the two.