AP Psychology Study Resource: Opponent Process Theory

Science explains to us how the body works.

We all have a fair idea of our anatomy, and how it works on a day to day basis.

However, some aspects of our body connect psychology and neurology.

While science can explain the action, psychology looks to the reason why the behavior exists. This is one part of the human body that’s been debated for centuries.

Many different psychologists have proposed theories based on their personal beliefs. Let’s take a look at one of these theories, and how it connects the mind to how our body functions.

What is the Opponent Process Theory?

The opponent process theory first came about when Ewald Hering developed it in 1878. Ewald Hering was a German physiologist.

Wikipedia explains that the opponent process theory is a neurological and psychological theory that helps to describe a wide range of human behaviors, including our ability to see in color.

The opponent process theory was later expanded on by a psychologist by the name of Richard Solomon in the 20th century, whom we’ll introduce a little later.

Hering took note of the fact that color combinations are existing that, as humans, we don’t ever get to see. These include yellowish-blue and reddish-green. He proposed through opponent process theory that three active opponent systems control our color perception.

Within this theory, Hering endeavored to suggest that we have three independent types of receptors. Each receptor type has opposing pairs. These are blue and yellow, red and green, and white and black.

Through the opponent process of our different receptors, each of these pairs produces different color combinations. This theory elaborates further on these differing receptors, suggesting that for each of the three pairs different chemicals occur and react in the retina for this purpose.

How Does the Opponent Process Theory Work?

So, how do these chemical reactions cause us to see in color?

Wikipedia continues by explaining that each of these chemical reactions causes the systematic building up of one color and the destroying of the other color within each pair.

Each pair of colors opposes each other. Your receptors for the color pair red-green cannot send messages to your brain about both shades simultaneously. The opponent process theory also helps to explain negative afterimages.

Negative afterimages are the perception of the destroyed color after you’ve seen the built-up member of the pair. This is because the chemical reaction reverses once you’ve seen one of the colors.

Let’s take the red-green pair and use it as an example of this. Red creates a positive response, while green, a negative one. Opponent neurons are responsible for these responses.

The opponent process theory also addresses color-blindness. Hering believed that color-blindness was due to the lack of a particular chemical existing in the eye.

A positive after-image will appear after we’ve stared at a brightly lit image. The image will vary with the intensifying and decreasing of the light used in the background of the picture.

Opponent Process Theory vs. Trichromatic Theory

Opponent Process Theory logo

So, if the opponent process theory is popular, what is Trichromatic theory and how does it relate to the opponent process theory?

Psyc explains that these two theories intend to illustrate different aspects of how we see in color and can work alongside one another.

The trichromatic theory was pioneered by Young and Helmholtz, who believed that individuals required three different wavelengths to see in color. Each wavelength has its own purpose and is in control of an entirely different set of chemicals.

Trichromatic theory believes that the overall balance of the three wavelengths is key to our perception of color.

The opponent process theory suggests that these three wavelengths exist, too. However, Hering believed that all three wavelengths existed within each color pairing of black and white, red and green, and blue and yellow.

Hering explains this through his theory of positive and negative chemical reactions through each color combination. Which of the three wavelengths that you hit is determined by the type of chemical reaction occurring within the color pairing.

With Trichromatic theory, it’s the opposite.

However, when bringing these two theories together, they complement each other. The trichromatic theory explains the science of color vision on a photoreceptor level.

Opponent process theory explains how color vision comes about as a result of how the photoreceptors are actually connected neurologically.

The Opponent-Process Theory in Action

The Opponent Process Theory circle colored

Sometimes, science comes to you. You can test out the theory of the opponent process yourself at home.

Healthline says you can use an experiment that can help to produce a negative afterimage. To conduct this experiment, you’ll need to place a small square of white paper in the center of a larger colored square.

The colored square can either be red, yellow, green or blue. Once you’ve centered your small white square, look at it for thirty seconds.

Immediately after this, look at another, much larger square of white paper and blink a couple of times.

Take note of the color of the afterimage you see.

Your afterimage should produce the opposite color to the one you’ve just looked at. This phenomenon is called cone fatigue.

As we learned above, the receptor cones in our eyes are one of three different wavelengths. If you look at the same color for an extended period, that particular cone receptor will become tired.

However, the cone receptors in your eyes responsible for looking at the opposing color have remained fresh and unused. They quickly replace the tired receptors, showing you the opposite color in your afterimage.  

The Opponent-Process Theory and Emotion

Lonely girl setting

It seems that the opponent process theory is already complex enough. However, Richard Solomon didn’t see it this way and believed that he could add more to it.

Healthline continues by describing how Solomon built on Hering’s opponent process theory with his own opinion of motivational states and emotion. Solomon’s theory looks at emotions and notes how there are opposites for almost all of them. For example, the opposite of fear is relief, and the opposite of pain is pleasure.

Solomon’s emotion theory proposed that when we experience one of these emotions, our body is automatically suppressing the conflicting feeling.

An example of this is when you are awarded a prize. When you’re handed your prize, you feel pleasure and joy. However, a little while after receiving it, you may experience opposing feelings of sadness.

While this secondary reaction will eventually disappear, it often lasts longer than the first emotion. After repeated exposure to a stimulus, the first emotion always fades, giving way to the secondary feeling which intensifies.

Over time, the secondary emotion can become the emotion most associated with that stimulus.

How It Relates to Drug Addiction

lying girl with medicine in the floor

The opponent process theory, along with its additional concepts contributed by Solomon, is a great way to explain what people experience when they go through drug addiction.

Medical News Today says that when a person is addicted to a drug or substance, the pleasure they’ll feel from the drug will slowly decrease over time. This eventually leads to the person getting no positive feelings out of taking the drug.

In fact, not only will they not feel pleasure, but they’ll resort to the negative feelings they first experienced when the drug subsided.

This is known as experiencing withdrawal symptoms.

The person addicted to the drugs is now taking them to avoid the emotions they feel when in withdrawal. This is because motivation and emotions are the most significant driving forces when it comes to addiction.

The longer a person is addicted to drugs, the more negative side effects they’ll experience. The person’s desire to avoid the negative withdrawal symptoms often gets in the way of their potential to quit.

One of the best ways of controlling the emotions a person experiences when addicted to drugs is by first maintaining control of the adverse effects. This will push their need for a motive forward, encouraging them to look beyond the negative emotions toward the positive outcome that lies ahead.

Looking at the Opponent Process Theory

Opponent Process Theory logo

In the human body, everything interconnects.

While the opponent-process theory first started out as a way to explain the ability to see in color, it’s now widely used to describe the psychological effects of drug addiction.

Science and psychology typically offer opposing theories that address different aspects of people as human beings. However, now and then, they come together to form revolutionary ideas regarding the intricate inner workings that make us who we are.

Whether the opponent process theory has led to more light shed on color vision or drug addiction, all we know is that it’s helped to explain multiple facets of how we function and why we behave the way we do.