Emotion classification


Emotion classification is the means by which one may distinguish or contrast one emotion from another. It is a contested issue in emotion research and in affective science.

Emotions as discrete categories

In discrete emotion theory, all humans are thought to have an innate set of basic emotions that are cross-culturally recognizable. These basic emotions are described as "discrete" because they are believed to be distinguishable by an individual's facial expression and biological processes. Theorists have conducted studies to determine which emotions are basic. A popular example is Paul Ekman and his colleagues' cross-cultural study of 1992, in which they concluded that the six basic emotions are anger, disgust, fear, happiness, sadness, and surprise. Ekman explains that there are particular characteristics attached to each of these emotions, allowing them to be expressed in varying degrees in a non-verbal manner. Each emotion acts as a discrete category rather than an individual emotional state.

Simplicity debate

Humans' subjective experience is that emotions are clearly recognizable in ourselves and others. This apparent ease of recognition has led to the identification of a number of emotions that are said to be basic, and universal among all people. However, a debate among experts has questioned this understanding of what emotions are. There has been recent discussion of the progression on the different views of emotion over the years.
On "basic emotion" accounts, activation of an emotion, such as anger, sadness, or fear, is "triggered" by the brain's appraisal of a stimulus or event with respect to the perceiver's goals or survival. In particular, the function, expression, and meaning of different emotions are hypothesized to be biologically distinct from one another. A theme common to many basic emotions theories is that there should be functional signatures that distinguish different emotions: we should be able to tell what emotion a person is feeling by looking at his or her brain activity and/or physiology. Furthermore, knowledge of what the person is seeing or the larger context of the eliciting event should not be necessary to deduce what the person is feeling from observing the biological signatures.
On "constructionist" accounts, the emotion a person feels in response to a stimulus or event is "constructed" from more elemental biological and psychological ingredients. Two hypothesized ingredients are "core affect" and conceptual knowledge. A theme common to many constructionist theories is that different emotions do not have specific locations in the nervous system or distinct physiological signatures, and that context is central to the emotion a person feels because of the accessibility of different concepts afforded by different contexts.

Dimensional models of emotion

For both theoretical and practical reasons, researchers define emotions according to one or more dimensions. In his 1649 philosophical treatise, The Passions of the Soul, Descartes defines and investigates the six primary passions. In 1897, Wilhelm Max Wundt, the father of modern psychology, proposed that emotions can be described by three dimensions: "pleasurable versus unpleasurable", "arousing or subduing", and "strain or relaxation". In 1954, Harold Schlosberg named three dimensions of emotion: "pleasantness–unpleasantness", "attention–rejection" and "level of activation".
Dimensional models of emotion attempt to conceptualize human emotions by defining where they lie in two or three dimensions. Most dimensional models incorporate valence and arousal or intensity dimensions. Dimensional models of emotion suggest that a common and interconnected neurophysiological system is responsible for all affective states. These models contrast theories of basic emotion, which propose that different emotions arise from separate neural systems. Several dimensional models of emotion have been developed, though there are just a few that remain as the dominant models currently accepted by most. The two-dimensional models that are most prominent are the circumplex model, the vector model, and the Positive Activation – Negative Activation model.

Circumplex model

The circumplex model of emotion was developed by James Russell. This model suggests that emotions are distributed in a two-dimensional circular space, containing arousal and valence dimensions. Arousal represents the vertical axis and valence represents the horizontal axis, while the center of the circle represents a neutral valence and a medium level of arousal. In this model, emotional states can be represented at any level of valence and arousal, or at a neutral level of one or both of these factors. Circumplex models have been used most commonly to test stimuli of emotion words, emotional facial expressions, and affective states.
Russell and Lisa Feldman Barrett describe their modified circumplex model as representative of core affect, or the most elementary feelings that are not necessarily directed toward anything. Different prototypical emotional episodes, or clear emotions that are evoked or directed by specific objects, can be plotted on the circumplex, according to their levels of arousal and pleasure.

Vector model

The vector model of emotion appeared in 1992. This two-dimensional model consists of vectors that point in two directions, representing a "boomerang" shape. The model assumes that there is always an underlying arousal dimension, and that valence determines the direction in which a particular emotion lies. For example, a positive valence would shift the emotion up the top vector and a negative valence would shift the emotion down the bottom vector. In this model, high arousal states are differentiated by their valence, whereas low arousal states are more neutral and are represented near the meeting point of the vectors. Vector models have been most widely used in the testing of word and picture stimuli.

Positive activation – negative activation (P.A.N.A.) model

The positive activation – negative activation or "consensual" model of emotion, originally created by Watson and Tellegen in 1985, suggests that positive affect and negative affect are two separate systems. Similar to the vector model, states of higher arousal tend to be defined by their valence, and states of lower arousal tend to be more neutral in terms of valence. In the P.A.N.A. model, the vertical axis represents low to high positive affect and the horizontal axis represents low to high negative affect. The dimensions of valence and arousal lay at a 45-degree rotation over these axes.

Plutchik's model

offers a three-dimensional model that is a hybrid of both basic-complex categories and dimensional theories. It arranges emotions in concentric circles where inner circles are more basic and outer circles more complex. Notably, outer circles are also formed by blending the inner circle emotions. Plutchik's model, as Russell's, emanates from a circumplex representation, where emotional words were plotted based on similarity. There are numerous emotions, which appear in several intensities and can be combined in various ways to form emotional "dyads".

PAD emotional state model

The PAD emotional state model is a psychological model developed by Albert Mehrabian and James A. Russell to describe and measure emotional states. PAD uses three numerical dimensions to represent all emotions. The PAD dimensions are Pleasure, Arousal and Dominance.
  • The Pleasure-Displeasure Scale measures how pleasant an emotion may be. For instance, both anger and fear are unpleasant emotions, and score high on the displeasure scale. However, joy is a pleasant emotion.
  • The Arousal-Nonarousal Scale measures how energized or soporific one feels. It is not the intensity of the emotion—for grief and depression can be low arousal intense feelings. While both anger and rage are unpleasant emotions, rage has a higher intensity or a higher arousal state. However boredom, which is also an unpleasant state, has a low arousal value.
  • The Dominance-Submissiveness Scale represents the controlling and dominant nature of the emotion. For instance, while both fear and anger are unpleasant emotions, anger is a dominant emotion, while fear is a submissive emotion.

    Criticisms

Cultural considerations

Ethnographic and cross-cultural studies of emotions have shown the variety of ways in which emotions differ with cultures. Because of these differences, many cross-cultural psychologists and anthropologists challenge the idea of universal classifications of emotions altogether. Cultural differences have been observed in the way in which emotions are valued, expressed, and regulated. The social norms for emotions, such as the frequency with or circumstances in which they are expressed, also vary drastically. For example, the demonstration of anger is encouraged by Kaluli people, but condemned by Utku Inuit.
The largest piece of evidence that disputes the universality of emotions is language. Differences within languages directly correlate to differences in emotion taxonomy. Languages differ in that they categorize emotions based on different components. Some may categorize by event types, whereas others categorize by action readiness. Furthermore, emotion taxonomies vary due to the differing implications emotions have in different languages. That being said, not all English words have equivalents in all other languages and vice versa, indicating that there are words for emotions present in some languages but not in others. Emotions such as the schadenfreude in German and saudade in Portuguese are commonly expressed in emotions in their respective languages, but lack an English equivalent.
Some languages do not differentiate between emotions that are considered to be the basic emotions in English. For instance, certain African languages have one word for both anger and sadness, and others for shame and fear. There is ethnographic evidence that even challenges the universality of the category "emotions" because certain cultures lack a specific word relating to the English word "emotions".