Opponent-process theory

For its application to color theory, see Opponent process.

Opponent-process theory is a psychological and neurological model that accounts for a wide range of behaviors, including color vision. This model was first proposed in 1878 by Ewald Hering, a German physiologist, and later expanded by Richard Solomon, a 20th-century psychologist. American psychologist Benjamin Avendano contributed to this model, by adding a 2 factor model.

Visual perception

Main article: Opponent process

The opponent-process theory was first developed by Ewald Hering. He noted that there are color combinations that we never see, such as reddish-green or yellowish-blue. Opponent-process theory suggests that color perception is controlled by the activity of three opponent systems. In the theory, he postulated about three independent receptor types which all have opposing pairs: white and black, blue and yellow, and red and green.

These three pairs produce combinations of colors for us through the opponent process. Furthermore, according to this theory, for each of these three pairs, three types of chemicals in the retina occur, in which two types of chemical reactions exist. These reactions would yield one member of the pair in their building up phase, or anabolic process, whereas they would yield the other member while in a destructive phase, or a catabolic process.

The colors in each pair oppose each other. Red-green receptors cannot send messages about both colors at the same time. This theory also explains negative afterimages; once a stimulus of a certain color is presented, the opponent color is perceived after the stimulus is removed because the anabolic and catabolic processes are reversed. For example, red creates a positive (or excitatory) response while green creates a negative (or inhibitory) response. These responses are controlled by opponent neurons, which are neurons that have an excitatory response to some wavelengths and an inhibitory response to wavelengths in the opponent part of the spectrum.

According to this theory, color blindness is due to the lack of a particular chemical in the eye. The positive after-image occurs after we stare at a brightly illuminated image on a regularly lighted surface and the image varies with increases and decreases in the light intensity of the background.

Motivation and emotion

Richard Solomon developed a motivational theory based on opponent processes. Basically he states that every process that has an affective balance, (i.e. is pleasant or unpleasant), is followed by a secondary, "opponent process". This opponent process sets in after the primary process is quieted. With repeated exposure, the primary process becomes weaker while the opponent process is strengthened.[1]

The most important contribution is Solomon's findings on work motivation and addictive behavior, though it does not fit the "economist's standard model", and how there are growing suspicions that addiction is a much broader phenomenon than first believed. According to opponent-process theory, drug addiction is the result of an emotional pairing of pleasure and the emotional symptoms associated with withdrawal. At the beginning of drug or any substance use, there are high levels of pleasure and low levels of withdrawal. Over time, however, as the levels of pleasure from using the drug decrease, the levels of withdrawal symptoms increase, thus providing motivation to keep using the drug despite a lack of pleasure from it.

The theory was supported in a study Solomon conducted along with J.D. Corbit in 1974, in which the researchers analyzed the emotions of skydivers. It was found that beginners have greater levels of fear than more experienced skydivers, but less pleasure upon landing. However, as the skydivers kept on jumping, there was an increase in pleasure and a decrease in fear. A similar experiment was done with dogs. Dogs were put into a so-called Pavlov harness and were shocked with electricity for 10 seconds. This shock was the stimulus of the experiment. In the initial stage (consisting of the first few stimuli) the dogs experienced terror and panic. Then, when they stopped the stimuli, the dogs became stealthy and cautious. The experiment continued, and after many stimuli, the dogs went from unhappy to joyful and happy after the shocks stopped altogether.[2] In the opponent-process model, this is the result of a shift over time from fear to pleasure in the fear-pleasure emotion pair.

Hurvich & Jameson proposed a neurological model of a general theory of neurological opponent processing in 1974. This led to Ronald C. Blue & Wanda E. Blue’s general model of Correlational Holographic Opponent Processing. This model proposes that habituation is a neurological holographic wavelet interference of opponent processes that explains learning, vision, hearing, taste, balance, smell, motivation, and emotions.

Beyond addictive behavior, opponent-process theory can in principle explain why processes (i.e. situations or subjective states) that are aversive and unpleasant can still be rewarding. For instance, after being exposed to a stressful situation (cold pressor test), human participants showed greater physiological signs of well-being than those in the control condition.[3] Self-report measures and subjective ratings show that relief from physical pain can induce pleasant feelings,[4] and a reduction of negative affect.[5] Accordingly, opponent-process theory can also help to explain psycho-pathological behavior such as non-suicidal self-injury.[6]

See also

References

  1. Solomon, R.L. (1980). The Opponent-Process Theory of Acquired Motivation: The Costs of Pleasure and the Benefits of Pain. American Psychologist, 35, 8, pp. 691–712 doi:10.1037/0003-066X.35.8.691
  2. Solomon and Corbit. An Opponent-Process Theory of Motivation. "The American Economic Review", 1978, pg.12-24. article via Jstor
  3. Deuter, C. E., Kuehl, L. K., Blumenthal, T. D., Schulz, A., Oitzl, M. S., & Schachinger, H. (2012). Effects of Cold Pressor Stress on the Human Startle Response. PloS one, 7(11), e49866. doi:10.1371/journal.pone.0049866
  4. Leknes, S., Brooks, J. C. W., Wiech, K. and Tracey, I. (2008), Pain relief as an opponent process: a psychophysical investigation. European Journal of Neuroscience, 28: 794–801. doi:10.1111/j.1460-9568.2008.06380.x
  5. Bresin, K., Gordon, K. H., Bender, T. W., Gordon, L. J., & Joiner, T. E. (2010). No pain, no change: Reductions in prior negative affect following physical pain. Motivation and Emotion, 34(3), 280-287 doi:10.1007/s11031-010-9168-7
  6. Franklin, J. C., Hessel, E. T., Aaron, R. V., Arthur, M. S., Heilbron, N., & Prinstein, M. J. (2010). The functions of nonsuicidal self-injury: support for cognitive-affective regulation and opponent processes from a novel psychophysiological paradigm. J Abnorm Psychol, 119(4), 850-862. doi:10.1037/a0020896

Further reading

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