An Overview of Opponent-Process Theory


Opponent-process theory is a psychological and neurological model that accounts for a wide range of behaviours, including colour vision. This model was first proposed in 1878 by Ewald Hering, a German physiologist, and later expanded by Richard Solomon, a 20th-century psychologist.

Opponent-process theory of drug addiction.

Visual Perception

The opponent-process theory was first developed by Ewald Hering. He noted that there are colour combinations that we never see, such as reddish-green or bluish-yellow. Opponent-process theory suggests that colour 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 colours for us through the opponent process. Furthermore, according to this theory, for each of these three pairs, three types of chemicals in the retina exist, in which two types of chemical reactions can occur. 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 colours in each pair oppose each other. Red-green receptors cannot send messages about both colours at the same time. This theory also explains negative afterimages; once a stimulus of a certain colour is presented, the opponent colour 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, colour 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.

The veracity of this theory, however, has recently been challenged. The main evidence for this theory derived from recordings of retinal and thalamic (LGN) cells, which were excited by one colour and suppressed by another. Based on these oppositions, the cells were called “Blue-yellow”, “Green-red” and “black-white” opponent cells. In a recent review of the literature, Pridmore notes that the definition of the colour ‘green’ has been very subjective and inconsistent and that most recordings of retinal and thalamic (LGN) neurons were of Red-cyan colour, and some of Green-magenta colour. As these colours are complementary and not opponent, he proposed naming these neurons as complementary cells.


A-process refers to the one of the emotional internal processes or responses of the opponent-process theory. The A-process is largely responsible for the initial, usually fast and immediate, emotional reaction to a stimulus. The theory considers it a primary process which may be affectively positive or negative, but never neutral. The theory also proposes that this process automatically causes a B-process, which is subjectively and physiologically opposite in direction to the A-process.

There is a peak response to any emotional stimulus which usually occurs rapidly, usually out of shock, but lasts only as long as the stimulus is present. In a physiological sense, the a-process is where the pupils dilate, the heart rate increases, and the adrenaline rushes.

A- and B-Processes

The A- and B-processes are consequently and temporarily linked but were believed to depend on different neurobiological mechanisms. B-Process, the other part of opponent-process theory, occurs after the initial shock, or emotion and is evoked after a short delay. A-process and B-process overlap in somewhat of an intermediate area. While A-process is still in effect, B-process starts to rise, ultimately levelling out a-process’ initial spike in emotion. A-process ends once the stimulus is terminated, leaves, or ends. Physiologically, this is where breathing returns to normal, pulse slows back to its normal rate, and heart rate starts to drop. The B-process can be thought of as the “after-reaction”. Once B-process has ended, the body returns to homeostasis and emotions return to baseline.

Research on the brain mechanisms of drug addiction showed how the A-process is equated with the pleasure derived from drugs and once it weakens, it is followed by the strengthening of the B-process, which are the withdrawal symptoms.

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.

The most important contribution is Solomon’s findings on work motivation and addictive behaviour. 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.

The theory was supported in a study Solomon conducted along with J.D. Corbit in 1974, in which the researchers analysed 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. In the opponent-process model, this is the result of a shift over time from fear to pleasure in the fear-pleasure emotion pair.

Another example of opponent processes is the use of nicotine. In the terms of Hedonism, one process (the initial process) is a hedonic reaction that is prompted by the use of nicotine. The user gains positive feelings through the inhalation of nicotine. This is then counteracted, or opposed, by the second, drug-opposite effect (the opponent process). The drug-opposite effect holds hedonic properties that are negative, which would be the decrease in positive feelings gained by the inhalation of nicotine. The counteraction takes place after the initial hedonic response as a means to restore homeostasis. In short, the use of nicotine jumpstarts an initial, pleasurable response. It is then counteracted by the opponent process that brings one back to their original level of homeostasis. The negative feelings begin to take hold again, which in this case would be the craving of nicotine. Repeated use of the substance will continue to strengthen the opponent process, but the feelings gained through the initial process will remain constant. This dynamic explains tolerance, which is the increase in the amount of drug/substance that is needed to overcome the opponent process that is increasing in strength. This also explains withdrawal syndrome, which occurs by the negative, drug-opposite effects remaining after the initial, pleasurable process dies out.

Leo Hurvich and Dorothea 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 behaviour, 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. Self-report measures and subjective ratings show that relief from physical pain can induce pleasant feelings, and a reduction of negative affect. Accordingly, opponent-process theory can also help to explain psychopathological behaviour such as non-suicidal self-injury.

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RTE Investigates: Ireland’s Unregulated Psychologists


RTÉ Investigates the lack of regulation of psychologists in the private sector where families of young children are forced to seek help because of long public waiting lists.


Reporter Barry O’Kelly shows how easy it is to call yourself a psychologist in Ireland today.

You can read comments made by the Psychological Society of Ireland (PSI) here (PDF, external link) regarding the programme.

Production & Filming Details

  • Director(s):
  • Producer(s):
  • Writer(s):
  • Music:
  • Cinematography:
  • Editor(s):
    • Hugh Ormond
  • Production:
    • RTE
  • Distributor(s):
    • RTE One
  • Release Date: 06 March 2023 (Ireland).
  • Running Time: 41 minutes.
  • Rating: Unknown.
  • Country: UK.
  • Language: English.

On This Day … 26 February [2023]

People (Births)

People (Deaths)

  • 1969 – Karl Jaspers, German-Swiss psychiatrist and philosopher (b. 1883)

Emile Coue

Émile Coué de la Châtaigneraie (26 February 1857 to 02 July 1926) was a French psychologist and pharmacist who introduced a popular method of psychotherapy and self-improvement based on optimistic autosuggestion.

Considered by Charles Baudouin to represent a second Nancy School, Coué treated many patients in groups and free of charge.

Sandie Shaw

Sandie Shaw, MBE (born Sandra Ann Goodrich; 26 February 1947) is a retired English singer. One of the most successful British female singers of the 1960s, she had three UK number one singles with “(There’s) Always Something There to Remind Me” (1964), “Long Live Love” (1965) and “Puppet on a String” (1967). With the latter, she became the first British entry to win the Eurovision Song Contest. She returned to the UK Top 40, for the first time in 15 years, with her 1984 cover of the Smiths song “Hand in Glove”. Shaw retired from the music industry in 2013.

Concentrating on a new career as a psychotherapist, Shaw opened the Arts Clinic in 1997 with her husband, to provide psychological healthcare and creative development to those in the creative industries.[6]: 387  The clinic is now styled Barefoot Therapy: The Arts Clinic and continues to provide psychological support for those in the fields of entertainment, media and sports. In 1998 she was invited to join the Royal Society of Musicians as an Honorary Professor of Music.

Karl Jaspers

Karl Theodor Jaspers (23 February 1883 to 26 February 1969) was a German-Swiss psychiatrist and philosopher who had a strong influence on modern theology, psychiatry, and philosophy. After being trained in and practicing psychiatry, Jaspers turned to philosophical inquiry and attempted to discover an innovative philosophical system. He was often viewed as a major exponent of existentialism in Germany, though he did not accept the label.

On This Day … 21 February [2023]


People (Births)

  • 1892 – Harry Stack Sullivan, American psychiatrist and psychoanalyst (d. 1949)
  • 1914 – Jean Tatlock, American psychiatrist and physician (d. 1944)
  • 1961 – Elliot Hirshman, American psychologist and academic

Harry Stack Sullivan

Herbert “Harry” Stack Sullivan (21 February 1892 to 14 January 1949, Paris, France) was an American Neo-Freudian psychiatrist and psychoanalyst who held that “personality can never be isolated from the complex interpersonal relationships in which [a] person lives” and that “[t]he field of psychiatry is the field of interpersonal relations under any and all circumstances in which [such] relations exist”. Having studied therapists Sigmund Freud, Adolf Meyer, and William Alanson White, he devoted years of clinical and research work to helping people with psychotic illness.

Jean Tatlock

Jean Frances Tatlock (21 February 1914 to 04 January 1944) was an American psychiatrist and physician. She was a member of the Communist Party of the United States of America and was a reporter and writer for the party’s publication Western Worker. She is also known for her romantic relationship with J. Robert Oppenheimer, the director of the Manhattan Project’s Los Alamos Laboratory during World War II.

The daughter of John Strong Perry Tatlock, a prominent Old English philologist and an expert on Geoffrey Chaucer, Tatlock was a graduate of Vassar College and the Stanford Medical School, where she studied to become a psychiatrist. Tatlock began seeing Oppenheimer in 1936, when she was a graduate student at Stanford and Oppenheimer was a professor of physics at the University of California, Berkeley. As a result of their relationship and her membership of the Communist Party, she was placed under surveillance by the FBI and her phone was tapped.

She suffered from clinical depression and died by suicide on 04 January 1944.

Elliot Hirshman

Elliot Lee Hirshman (born 21 February 1961) is an American psychologist and academic who is the president of Stevenson University in Owings Mills, Maryland since 03 July 2017. Prior to Stevenson University he served as president at San Diego State University and served as the provost and senior vice president of the University of Maryland, Baltimore County.

On This Day … 20 February [2023]

People (Births)

  • 1893 – Elizabeth Holloway Marston, American psychologist and author (d. 1993)

People (Deaths)

  • 1996 – Solomon Asch, American psychologist and academic (b. 1907)

Elizabeth Holloway Marston

Sarah Elizabeth Marston (née Holloway; 20 February 1893 to 27 March 1993) was an American attorney and psychologist. She is credited, with her husband William Moulton Marston, with the development of the systolic blood pressure measurement used to detect deception; the predecessor to the polygraph.

She is also credited as the inspiration for her husband’s comic book creation Wonder Woman, a character fashioned on their polyamorous life partner, Olive Byrne.

Solomon Asch

Solomon Eliot Asch (14 September 1907 to 20 February 1996) was a Polish-American Gestalt psychologist and pioneer in social psychology. He created seminal pieces of work in impression formation, prestige suggestion, conformity, and many other topics. His work follows a common theme of Gestalt psychology that the whole is not only greater than the sum of its parts, but the nature of the whole fundamentally alters the parts. Asch stated: “Most social acts have to be understood in their setting, and lose meaning if isolated. No error in thinking about social facts is more serious than the failure to see their place and function” (Asch, 1952, p.61). Asch is most well known for his conformity experiments, in which he demonstrated the influence of group pressure on opinions. A Review of General Psychology survey, published in 2002, ranked Asch as the 41st most cited psychologist of the 20th century.

On This Day … 12 February [2023]

People (Births)

  • 1861 – Lou Andreas-Salomé, Russian-German psychoanalyst and author (d. 1937)
  • 1918 – Norman Farberow, American psychologist and academic (d. 2015)

Lou Andreas-Salome

Lou Andreas-Salomé (born either Louise von Salomé or Luíza Gustavovna Salomé or Lioulia von Salomé, Russian: Луиза Густавовна Саломе; 12 February 1861 to 05 February 1937) was a Russian-born psychoanalyst and a well-travelled author, narrator, and essayist from a French Huguenot-German family. Her diverse intellectual interests led to friendships with a broad array of distinguished thinkers, including Friedrich Nietzsche, Sigmund Freud, Paul Rée, and Rainer Maria Rilke.

Norman Farberow

Norman Louis Farberow (12 February 1918 to 10 September 2015) was an American psychologist, and one of the founding fathers of modern suicidology. He was among the three founders in 1958 of the Los Angeles Suicide Prevention Centre, which became a base of research into the causes and prevention of suicide.

On This Day … 11 February [2023]

People (Births)

  • 1925 – Virginia E. Johnson, American psychologist and academic (d. 2013)

People (Deaths)

  • 1958 – Ernest Jones, Welsh neurologist and psychoanalyst (b. 1879)

Virginia E. Johnson

Virginia E. Johnson (born Mary Virginia Eshelman; 11 February 1925 to 24 July 2013) was an American sexologist and a member of the Masters and Johnson sexuality research team. Along with her partner, William H. Masters, she pioneered research into the nature of human sexual response and the diagnosis and treatment of sexual dysfunctions and disorders from 1957 until the 1990s.

Ernest Jones

Alfred Ernest Jones FRCP MRCS (01 January 1879 to 11 February 1958) was a Welsh neurologist and psychoanalyst. A lifelong friend and colleague of Sigmund Freud from their first meeting in 1908, he became his official biographer. Jones was the first English-speaking practitioner of psychoanalysis and became its leading exponent in the English-speaking world. As President of both the International Psychoanalytical Association and the British Psycho-Analytical Society in the 1920s and 1930s, Jones exercised a formative influence in the establishment of their organisations, institutions and publications.

On This Day … 07 February [2023]

People (Births)

People (Deaths)

  • 2015 – Marshall Rosenberg, American psychologist and author (b. 1934)

Alfred Adler

Alfred Adler (07 February 1870 to 28 May 1937) was an Austrian medical doctor, psychotherapist, and founder of the school of individual psychology. His emphasis on the importance of feelings of belonging, family constellation and birth order set him apart from Freud and other members of the Vienna Circle. He proposed that contributing to others (Social Interest or Gemeinschaftsgefuhl) was how the individual feels a sense of worth and belonging in the family and society. His earlier work focused on inferiority, the inferiority complex, an isolating element which plays a key role in personality development. Alfred Adler considered a human being as an individual whole, and therefore he called his psychology “Individual Psychology” (Orgler 1976).

Adler was the first to emphasize the importance of the social element in the re-adjustment process of the individual and to carry psychiatry into the community. A Review of General Psychology survey, published in 2002, ranked Adler as the 67th most eminent psychologist of the 20th century.

Marshall Rosenberg

Marshall Bertram Rosenberg (06 October 1934 to 07 February 2015) was an American psychologist, mediator, author and teacher. Starting in the early 1960s, he developed nonviolent communication, a process for supporting partnership and resolving conflict within people, in relationships, and in society. He worked worldwide as a peacemaker and in 1984, founded the Centre for Nonviolent Communication, an international non-profit organisation for which he served as Director of Educational Services.

According to his biographer, Marjorie C. Witty, “He has a fierce face – even when he smiles and laughs. The overall impression I received was of intellectual and emotional intensity. He possesses a charismatic presence.”

On This Day … 06 February [2023]

People (Births)

  • 1839 – Eduard Hitzig, German neurologist and psychiatrist (d. 1907)
  • 1852 – C. Lloyd Morgan, English zoologist and psychologist (d. 1936)

People (Deaths)

  • 2012 – David Rosenhan, American psychologist and academic (b. 1929)

Eduard Hitzig

Eduard Hitzig (6 February 1838 to 20 August 1907) was a German neurologist and neuropsychiatrist of Jewish ancestry born in Berlin.

He studied medicine at the Universities of Berlin and Würzburg under the instruction of famous men such as Emil Du Bois-Reymond (1818–1896), Rudolf Virchow (1821–1902), Moritz Heinrich Romberg (1795–1873), and Karl Friedrich Otto Westphal (1833–1890). He received his doctorate in 1862 and subsequently worked in Berlin and Würzburg. In 1875, he became director of the Burghölzli asylum, as well as professor of psychiatry at the University of Zurich. In 1885, Hitzig became a professor at the University of Halle where he remained until his retirement in 1903.

Hitzig is remembered for his work concerning the interaction between electric current and the brain. In 1870, Hitzig, assisted by anatomist Gustav Fritsch (1837–1927), applied electricity via a thin probe to the exposed cerebral cortex of a dog without anaesthesia. They performed these studies at the home of Fritsch because the University of Berlin would not allow such experimentation in their laboratories. What Hitzig and Fritsch had discovered is that electrical stimulation of different areas of the cerebrum caused involuntary muscular contractions of specific parts of the dog’s body. They identified the brain’s “motor strip”, a vertical strip of brain tissue on the cerebrum in the back of the frontal lobe, which controls different muscles in the body. In 1870, Hitzig published his findings in an essay called Ueber die elektrische Erregbarkeit des Grosshirns (On the Electrical Excitability of the Cerebrum). This experimentation was considered the first time anyone had done any localised study regarding the brain and electric current.

However this was not the first time Hitzig had experienced the interaction between the brain and electricity; earlier in his career as a physician working with the Prussian Army, he experimented on wounded soldiers whose skulls were fractured by bullets. Hitzig noticed that applying a small electric current to the brains of these soldiers caused involuntary muscular movement.

Hitzig and Fritsch’s work opened the door to further localised testing of the brain by many others including Scottish neurologist, David Ferrier.

C. Lloyd Morgan

Conwy Lloyd Morgan, FRS (06 February 1852 to 06 March 1936) was a British ethologist and psychologist. He is remembered for his theory of emergent evolution, and for the experimental approach to animal psychology now known as Morgan’s Canon, a principle that played a major role in behaviourism, insisting that higher mental faculties should only be considered as explanations if lower faculties could not explain a behaviour.

David Rosenhan

David L. Rosenhan (22 November 1929 to 06 February 2012) was an American psychologist. He is best known for the Rosenhan experiment, a study challenging the validity of psychiatry diagnoses.

On This Day … 04 February [2023]

People (Deaths)

  • 1987 – Carl Rogers, American psychologist and academic (b. 1902).

Carl Rogers

Carl Ransom Rogers (08 January 1902 to 04 February 1987) was an American psychologist and among the founders of the humanistic approach (and client-centred approach) in psychology. Rogers is widely considered one of the founding fathers of psychotherapy research and was honoured for his pioneering research with the Award for Distinguished Scientific Contributions by the American Psychological Association (APA) in 1956.

The person-centred approach, Rogers’s unique approach to understanding personality and human relationships, found wide application in various domains, such as psychotherapy and counselling (client-centred therapy), education (student-centred learning), organisations, and other group settings. For his professional work he received the Award for Distinguished Professional Contributions to Psychology from the APA in 1972. In a study by Steven J. Haggbloom and colleagues using six criteria such as citations and recognition, Rogers was found to be the sixth most eminent psychologist of the 20th century and second, among clinicians, only to Sigmund Freud. Based on a 1982 survey of 422 respondents of US and Canadian psychologists, he was considered the most influential psychotherapist in history (Freud ranked third).