Freud’s understanding of anxiety as the core of psychological distress is partially responsible for the focus on negative emotions of affect researchers. Fear/anxiety, sadness/depression, and anger/hostility were traditionally at the forefront of affect research whereas positive emotional states were largely ignored. The focus on negative moods was reinforced by researchers (Cameron and Seyle) who established the negative physical consequences of chronic negative emotional states. Due to these hazardous consequences, research on negative affect remained the only type of affect research. Meehl, the researcher responsible for the first major breakthrough in positive affect research, first legitimized the study of positive emotions. Meehl established the concept of the “hedonic capacity” which he referred to as “joy juice”. Meehl argued that physicians and clinicians must seriously consider the psychological, individual differences of people who are born with more of this “joy juice” than others. Meehl also assumed that levels of hedonic capacity were largely independent from negative emotions in individuals. Finally, in support of Meehl's concepts, subsequent researchers developed the independent concepts of negative and positive affect. These dimensions, measurable as short term and long term states, can exist in intra and interpersonal contexts and are consistently apparent in different situations (different cultures, languages, time frames etc.). These two dimensions represent evolutionarily adaptive subjective states. Negative affectivity represents the extent to which humans are inclined to “turn away” from dangerous stimuli. Consequently, this system is referred to as the “withdrawal system”. For example, the disposition to experience intense fear/anxiety is useful for avoiding predators in the wild. The disposition to experience intense feelings of disgust is useful for avoiding poisonous foods. Positive affectivity, on the other hand, is representative of “turning toward” potentially rewarding stimuli. This system is known as the “approach system”. Our ancestors were directed toward situations that would yield pleasure. For example, it was necessary for our ancestors to engage in certain behaviours such as eating, mating, and cooperating with others. Therefore, it was adaptive for organisms to enjoy such necessary behaviours for the survival of the species.
Self-reported affectivity (the two broad dimensions of positive and negative affect) can be teased apart into smaller, distinct categories of affectivity. In this structure, “upper” levels of affect are indicative of whether the mood state can be considered pleasant or unpleasant, whereas the “lower” levels of affectivity describe the specific content of mood states (specifically what makes the mood state positive or negative).
Due to the history of extensive research surrounding specific types of negative affect, there is a high level of consensus that exists surrounding its measurement. On the other hand, there is very little research and consensus on the various dimensions (and measurement) of positive affectivity. Typically, the two “levels” of positive affectivity are general affectivity and affectivity related to a specific construct. The general form is indicative of the person’s trait characteristics whereas there are several scales that are relevant to specific constructs (such as Activity and Positive Emotions Scale). The several scales that exist describe different lower levels of positive affectivity. Although some tests label “lower levels” differently, there is a high correlation amongst similar levels on different tests. However, the correlation is not so high that these levels can be interchanged.
Positive affectivity scales are also highly correlated to general traits of personality. Extroversion is particularly related to positive affectivity. In fact, extraversion scores predict increases in positive mood following a pleasant mood induction but are unrelated to negative mood changes following an unpleasant mood induction. People with higher positive affectivity, such as extroverts, are more sensitive to and derive more pleasure from rewarding stimuli. Also, extraversion is strongly correlated with such positive affectivity constructs as joviality, moderately correlated with self-assurance, and modestly related to attentiveness (which is strongly correlated to conscientiousness). In general, extraverts report higher levels of cheerfulness, enthusiasm, and energy than introverts. Positive affectivity has, therefore, been linked to individual differences in social and interpersonal activity.
A person standing on a trait must be relatively stable across time in order to maintain a relatively consistent rank over various assessments. Also, scores on the trait should manifest some consistency across all situations and contexts. Positive affectivity has been found to be highly stable in older adults. In fact, there has been no systematic variation of positive affectivity scores with age. However, one exception has been found according to Helson and Klohnen (1998): positive affectivity scores dramatically increased from age 27-43 but stayed stable between ages 43-52.
Because the study of positive affectivity is so new, data and consistency across situations is sparse. However, the little amount of research available does indicate that individuals who experience enthusiasm and cheer while among others were more likely to experience enthusiasm and cheer when alone.
Positive affectivity operates in a well-defined endogenous circadian cycle. It is most adaptive for people to experience positive emotions when the potential for reward is high and the risk of danger is low. Otherwise, it is adaptive to conserve precious energy. Therefore, the variability of positive affectivity is innate in the human biology, and any changes to the variability over the course of evolution have been to ensure that the variability remains within reasonable bounds. The individual differences observed in positive affectivity are, therefore, reflective of the quality and functioning of genetics, neurobiological functions, as well as demographic and environmental components.
Due to the lack of research on positive affectivity levels, most genetic research in relation to this topic is based on extraversion. Twin studies revealed that extraversion is strongly heritable (between .40 and .60). Therefore, a common rearing environment exerts little influence on this personality trait. Literature involving measures of positive affectivity is more rare but has yielded similar results.
Happy individuals show more resting activity in the left prefrontal cortex than in the right prefrontal area. On the other hand, individuals who are described as dysphoric (unable to experience pleasure) display relatively greater right anterior activity. All in all, it seems as though positive affectivity is strongly associated with the level of resting activity in the left prefrontal area. This area in the brain has been linked to the mesolimbic dopaminergic system. This system is often referred to as the “reward” or “pleasure” centre in the brain: it facilitates the subjective experience of positive mood.
Considering the high level of heritability, it is clear that objective demographic factors are relatively weak predictors of happiness and positive affectivity. Variables such as income, education, and socioeconomic status are weakly related to happiness and wellbeing. Therefore, an individual’s capacity for positive affectivity is not seriously limited by objective conditions such as age, wealth, or status. Furthermore, there seems to be no sex difference in happiness levels. However, two variables have consistently emerged as significant predictors of positive affectivity: social behavior and spirituality. Therefore, extraverts engaged in social activity are more likely to be high in positive affectivity. Furthermore, people who report a strong commitment to a religious affiliation, attend services regularly, and engage in traditional religious beliefs have higher levels of positive affectivity.
Low levels of positive affectivity are associated with things like social phobia, agoraphobia, eating disorders, substance abuse disorders, and mood disorders. In particular, low levels of positive affectivity are strongly linked to the melancholic subtype of major depression. Therefore, there is a possibility that a lack of positive affectivity may be an important vulnerability factor for mood disorders. The cyclic nature of positive affectivity may explain the cyclic course of many mood disorders. For example: bipolar disorder is characterized by well-defined episodes of mania and depression, major depression tends to occur in episodes that may spontaneously remit over time, melancholic depression manifests in different levels of severity over the course of a day, and seasonal affective disorder is typically most intense in the winter months. It is unlikely that these circadian and seasonal trends that parallel those observed with positive mood is coincidental. Also, mood disorders are highly related to disturbances in the sleep-wake cycle. Given that positive affectivity also varies as a function of the sleep-wake cycle, it is reasonable to conclude that positive affectivity, sleep, and mood disorders all reflect common underlying mechanisms.
Individuals who are high in positive affectivity report greater satisfaction with important aspects of their lives such as careers and relationships. Positive affectivity is a significant predictor of relationship and marital satisfaction, whereas negative affectivity scores obtained early in a relationship predict its subsequent course.
As previously described, positive affectivity is not highly constrained by objective life conditions such as age, wealth, or status. Therefore, virtually anyone is capable of experiencing high levels of positive affectivity. It has been demonstrated that most people describe themselves as experiencing at least moderate levels of positive emotionality; however, many of us would like to be happier than we are. Although change may not be easy, it is possible. Significant life events eventually leave people’s positive affectivity levels unchanged - people eventually adapt to these events and move back to a pre-existing “set point”. Positive affectivity levels are strongly influenced by hereditary factors that influence central nervous system functioning. However, this heritability does not mean that positive affectivity is static, rather, genotypes typically establish the maximum and minimum phenotypic values that are possible for a given individual. Therefore, change is possible. We can increase our positive mood and move closer to our potential maximum.
Enhancing positive affectivity depends on three general principles that emerge from research in this area: more related to action than thought, striving after goals rather than attaining them, best achieved with an underlying understanding of the mood system. By monitoring our moods and becoming more sensitive to them, we should be able to maximize feelings of efficacy and enjoyment.
