# Motivation and emotion/Book/2014/Introversion and emotion

* Multimedia presentation (5 min)

## Overview

If you are the type of person who prefers reading a book in the solitude of places like a library, or other quiet places, as opposed to large social gatherings with lots of noise and chatter[grammar?]? If you do, chances are you have probably been referred to as an introvert by one or more people close to you. This is also likely the case if you are considered a deep and reflective thinker who is acutely aware of their own disposition. As an introvert you are likely to feel comfortable seeking out the ‘quiet-life’, or the ‘quieter-life’, than some of your more Extraverted peers. But does this preference for the quiet life indicate inherent differences or underlying problems with how an introverted person deals with life’s daily stresses? This chapter will aim to provide an insight and understanding of the theories and concepts underlying the trait of introversion and how to best apply the current knowledge available to improve one’s life.

### What is a personality trait?

Personality traits are stable patterns of behaviour that occur within specific contexts (Matthews, Deary & Whiteman, 2003). In other words, while a person’s behaviour may vary from occasion to occasion, we can generally observe and predict a consistent pattern of behaviour from them in certain situations based on their personality traits. This variation in behaviour may be explained by things such as temporary mood states or extreme stress (Matthews, Deary & Whiteman, 2003) but if we were to repeatedly expose a person to a specific situation it would be expected that their average behavioural response would be representative and reflective of their personality traits. For example, if a student who is described by their work-colleagues as being a friendly and approachable person was feeling intense stress and pressure about an upcoming exam they might behave in an irritable and aggressive manor at their workplace. However, once the exam has been finished the students behaviour at their workplace may return to being friendly and approachable reflecting the friendly disposition and personality traits described by their co-workers.
Personality traits are considered stable and inflexible over time and the causal relationship that they have on human behaviour has been well documented (Matthews, Deary & Whiteman, 2003). Personality traits are used to describe ourselves and others to the world, too[spelling?] explain our behaviour, thoughts and feelings and to influence and shape individual dispositions (Salgado, 2004). It is important to understand that Introversion was first conceptualized as a rigid and independent personality trait that could explain potentially undesirable or abnormal behaviours[factual?]. Once this distinction is made its current relationship to other personality traits, Extraversion most notably, and the behavioural effects of the trait can be further evaluated and understood.

### What is introversion?

Very few personality traits have received as much attention in psychological academia as Introversion and Extraversion (Guilford & Braly, 1930). The source responsible for the original conception of Introversion and Extraversion is unclear, however most agree that Carl Jung popularized the concept and the experimental study of the traits in the early 1900s (Guilford & Braly, 1930). Jung stated that Introverts and Extraverts are characterized by their tendencies to channel their ‘psychic’ or ‘libidic’ energy inwards (Introverts) or outwards (Extraverts) (Matthews, 2004) (Guilford & Braly, 1930). An Introvert is usually characterized as a person who displays a quiet and reserved disposition, is a deep, introspective thinker, enjoys his/her own company and does not enjoy large social or group activities (Heffernan & Ling, 2001). It is important to note that this description of Introvert may paint the picture of a lonely anti-social individual who is incapable of social interaction and intimate relationships. Introverts are, however, capable of such relationships and, when compared to Extraverts, the intimacy of the aforementioned relationships has been shown to be stronger and more meaningful (Burger, 2011).

### Introversion/Extraversion

It is almost impossible to talk about Introversion without mentioning the relationship it has with Extraversion. People who display the Extraversion personality trait are socially outgoing, gregarious and enthusiastic/talkative people (Conklin, 1923) or, in simpler terms, the opposite of an Introvert. Hans Eysenck (Matthews, 2004) was one of the first psychologists to postulate that both Introversion and Extraversion shouldn’t be thought of as rigid independent traits but rather as a continuum. At both ends of this Introversion-Extraversion continuum would be people whose personality is extremely Introverted or Extraverted. Eysenck theorized however (Matthews, 2004) that [missing something?] the entire population were to have the personality measured for Introversion/Extraversion that we would expect to find a normal distribution bell-curve along this continuum. In other words, while everyone’s personality is to some varying degree Introverted or Extraverted it is more likely that an individual has an equal amount of Introverted and Extraverted traits than it is to be completely Introverted or Extraverted. Furthermore it was once considered that any rare case of a person being identified as extremely Introverted or Extraverted should be considered pathological (Guilford & Braly, 1930). It is important to note that while Introversion and Extraversion are distinct and separate dimensions of personality that they will always be inextricably linked to one another along this continuum. The majority of research conducted on Introversion also aims to analyse and elucidate phenomena related to Extraversion and because of this link the effects of Introversion will always be compared and contrasted against that of Extraversion.

### Theories of introversion
#### Eysenck's heirarchical model

Eysenck’s research on personality lead him to conduct a thorough and robust factorial analysis in search of identifying personality traits and super-traits within his Hierarchical Model of Personality (Burger, 2011). Eysenck concluded that all personality traits can be categorized into three distinct dimensions (or as he referred to them super-traits); Introversion-Extraversion, Neuroticism and Psychotism (Eysenck & Eysenck, 1968). Eysenck was not only one of the first psychologists to put forward the idea of an Introversion-Extraversion continuum but he was also one of the first psychologists to adopt a biological/physiological approach to studying Introversion. Eysenck (1967) theorized that the primary physiological difference between Introverts and Extraverts is a difference in cortical arousal levels when in a resting state or low stimulation level environment. He further hypothesized that Extraverts reach their optimal cortical arousal levels by displaying a gregarious, friendly and talkative disposition and by seeking out highly stimulating social events (Eysenck, 1967). Introverts on the other hand obtain their optimal cortical arousal levels by seeking out solitary or non-stimulating situations and environments. A good example of this optimal cortical arousal preference may be seen in students. An Introvert is more likely to study alone in a quiet (non-stimulating) area of a library while an Extravert is more likely to seek out a noisy study area where social interaction is possible and probable (highly stimulating) (Burger, 2011).

#### Gray's reinforcement sensitivity theory

Gray built upon Hans Eysenck’s biological/physiological research on Introversion/Extraversion by incorporating elements of Operant Conditioning (Matthews & Gilliland, 1999). Gray hypothesized that three distinct brain systems; the Behavioural Activation System (BAS), the Behavioural Inhibition System (BIS) and the Fight/Flight System (FFS) and their respective biological sensitivity thresholds were what governed much of the behaviour and emotions of Introverts and Extraverts. Gray postulated that most Extraverts have a highly active BAS which motivates them to find and achieve pleasurable goals/activities (Burger, 2011). According to Matthews and Gilliland (1999) rewards, and anticipation of reward, are less satisfying for Introvert. Gray postulated that Introverts are more motivated to avoid punishment, or the possibility of punishment, and are more likely to have highly active BIS. This results in a Introverts being apprehensive, weary and fearful of new or potentially threatening situations (Aron & Aron, 1997).

#### Current biological/physiological theories

Current research has been unable to replicate these specific cortical arousal results however current research has been able to elucidate other biological/physiological differences in Introverts. Klinteberg, Schalling, Edman, Oreland and Asberg (1987) demonstrated differences in the neurotransmitter MAO (Monoamine Oxidase) platelet activity[explain?][Provide more detail]. Aron and Aron (1997) evidenced greater right hemisphere brain activity in Introverts[Provide more detail] and Haier, Reynolds, Prager, Cox and Buchsbaum (1991) reported differences in effect of caffeine on Introverts, suggesting it may increase their sensitivity to pain. There are numerous studies that highlight the biological, chemical and physiological differences of Introverts but Bullock and Gilliland (1993) probably surmised the currently known differences best by suggesting that Introverts are simply more a little bit more sensitive to stimulation than the average person.

### Introversion and sensitivity

The biological differences and preference that Introverts demonstrate for low to non-stimulating environments has been empirically proven and replicated, but what functional effects do they have on the life on an Introvert? While it is likely to find things like large parties and other similar social gatherings uncomfortable and overwhelming for an Introvert that doesn’t necessarily imply that they have an anti-social personality or are paralysed by fear of such situations. Despite sensitivity’s proven independence from such factors as fearfulness, neuroticism, reactivity and inhibitedness highly sensitive people are often confused or inappropriately labelled with the aforementioned negative emotional states (Aron & Aron, 1997). Sensitivity has been shown to predispose and predict highly sensitive individual's exhibition of fearfulness, over-arousal and depressed mood if they are repeatedly exposed to negative experiences and stimuli (Aron & Aron, 1997). The trait of sensitivity itself though has no relevant research that suggests a causal link between it and such negative emotions (Aron & Aron, 1997). In other words, highly sensitive people (Introverts) are more likely to experience a negative emotional affect when presented with aversive experiences because they perceive and are more reactive to distressing stimuli. Sensitivity can increase the likelihood and intensity of such negative emotions but the aversive stimuli itself or maladaptive behaviours and cognitions are the root of the negative emotions.
It is important to clarify that the main effect of sensitivity in Introverts is over-arousal and that this over-arousal effect is two-tailed (Aron & Aron, 1997). For example a highly sensitive introvert is more likely to experience intensely positive emotions when repeatedly presented with desirable and pleasant experiences in the same way they would experience intense negative emotions when presented with undesirable and unpleasant experiences. To further demonstrate that Introversion was less responsible for negative emotional states than environmental factors, Aron and Aron (1997) and Gunnar (1994) found than when measuring a large cluster of highly sensitive people that poor parenting and negative early childhood experiences were a better predictor of negative emotionality than Introversion or sensitivity was.
Generally speaking, Introverts are more likely to experience positive emotions and pleasant experiences if they engage in low-stimulating events or environments and avoid events of environments that will trigger over-arousal. A practical example of this for an Introvert may be taking a date and/or friend to an art gallery as opposed to a music concert. This will enhance the Introvert's own experience and subsequently make socialising easier and more pleasant for both parties.

### Introversion, happiness and well-being

Happiness and well-being are subjective in their nature (Diener, Suh, Lucas & Smith, 1999). What makes one man or woman happy does not necessarily make another man or woman happy. Certain situations or experiences can be considered universal in how they affect a positive mood in people; receiving a gift for example, but in terms of academically measuring and examining the emotional state of happiness and well-being research must rely heavily on self-reports and other subjective measures. Introversion’s effect on an individual’s level of happiness and well-being, as is the case with the majority of research surrounding Introversion, is most often compared and concerned with its relationship to Extraversion (Burger, 2011). Current empirical research holds that Introversion and Extraversion should be thought of as a continuum as opposed to two singular independent traits. Just because research primarily reports differences between Introverts and Extraverts anyone who is highly introverted is also likely to exhibit significantly different behaviour and emotions when compared to non-introverted persons. Overall, Introverts report lower levels of general happiness than extraverts do (Lucas, Le & Dyrenforth, 2008)[Provide more detail].
There are two hypothesized reasons behind these findings; the first being the aforementioned sensitivity theory and the second being a sociability theory (Burger, 2011). As explained in Eysenck Hierarchical Model and Gray’s Reinforcement Sensitivity Theory Introverts are less motivated and find less pleasure in receiving rewards/positive reinforcement than the average person (Matthews & Gilliland, 1999) (Eysenck & Eysenck, 1968). As such Introverts are less likely to seek out situations in which a reward can or will be attained and do not always see the same possibility for reward in situations that other non-introverts may do (Burger, 2011). A laboratory study conducted by Larsen and Ketelaar (1989) found that Extraverts reported significantly higher levels of happiness than Introverts when informed about receiving a very good grade on a made-up test. Again it is important to note than Introverts do take satisfaction and happiness from achievement but they are likely to experience a lower intensity of such emotions and demonstrate less motivation to seek out situations in which a reward is likely. For example an Introvert is likely to jump on a roller-coaster because they do not perceive the adrenaline rush a roller-coaster provides as rewarding. Instead they are more likely to approach the roller-coast apprehensively and avoid the fear (punishment) that is inherent when riding roller-coasters.
The second reason Introverts are hypothesized to report lower levels of happiness is tied into the characteristics of the trait itself. Extraverts generally socialize more than Introverts and therefore have a larger social support network of friends (Srivastava, Angelo & Vallereux, 2009). Having a large social support network, or having lots of friends, has been shown to be closely correlated with positive self-reported well-being. Burger (2011) reports that friends increase feelings of competence, self-esteem and can serve as a buffer against stress. It is important to note that while Introverts are generally less socialable and are likely to have a smaller social circle that they are still very capable of developing meaningful and intensely intimate relationships that provide their own source of happiness and well-being for the individual.

### Introversion in the workplace

Personality types and traits influence a wide array of behaviours and emotions on a daily basis. This influence obviously affects our behaviour in the workplace and furthermore can be used to identify areas or roles within the workplace in which our personality type and disposition can be most effectively and efficiently used (Chauhan & Chauhan, 2001). In the workplace Introverts are known for such desirable qualities as calmness, reservedness, comfort/effectiveness when working alone and for such undesirable qualities as trouble collaborating and co-operating with others and not being proactive/action motivated (Chauhan & Chauhan, 2001). Chauhan and Chaunhan suggest that Introverts are best suited for roles in which nurturing, creativity and discipline are highly valued and desired. Jobs such as scientists, philosophers, artists and mechanics are good examples of jobs in which these values can be utilized most effectively and efficiently. These types of jobs reflect Introverts inherent preference for solitary and reflective activities (Matthews, 2004). An understanding of an individual’s personality type can be used to better identify and place employees in roles or positions that can most effectively emphasize their strengths in workplace settings.

### Introversion and clinical disorders

Introverts are often misunderstood and mislabelled as being anxious or socially withdrawn however Introversion, especially when compared to Extraversion, is not as strongly linked to emotional pathology as most would think (Matthews, 2004). The personality traits of Extraversion and Neuroticism are the traits most strongly correlated with anxiety and other mood disorders but Introversion has been shown to increase vulnerability to stress and also to predict anhedonia (a common symptom of Depression) (Matthews, 2004). Introversion has long been associated with Depression and studies examining this relationship do not deny the correlation between but any concrete cause and effect has not been found between Introversion and Depression (Matthews, 2004). This may be due to the fact that Introversion and Depression share similar symptoms (social withdrawal and isolation for example) which raises the question does Introversion predispose an individual to Depression or visa versa. Lastly, Introversion has also been linked to Schizoid Personality Disorder, which increases an individual’s risk of developing Schizophrenia or experiencing a psychotic episode (Casima, Bockbrader, Lysaker, Rae, Brenner & O’Donnell, 2005), however this association is again hypothesized to be due to sharing similar symptoms (social withdrawal and inhibition) (Matthews, 2004). In summary, Introversion has been linked and correlated with a number of different clinical disorders however the little evidence about the cause and effect relationship between the personality trait and the symptoms of such disorders is available. Introversion may increase risk or predispose people to certain clinical disorders or maladaptive behaviours but there is little an individual can change in their own lifestyle and behaviour to change these facts.

### Conclusion

Introverts differ from the average person in many ways. From sensitivity thresholds to the way they socialize it is sometimes obvious and easy to tell whether or not a person is an Introvert. The primary differences outlined in this chapter aim to explain some of the biological and physiological (Eysenck and Gray's sensitivity theories) reasons behind Introverted behaviour and emotion whilst also discussing what effects and implications these differences have on an Introverts everyday life. Ultimately it is useless trying to change an Introvert's preferance for the the 'quiet-life' (or for low--stimulating events/environments) as it will only serve to over-arouse them and cause psychological discomfort. In the the workplace, educational settings and other everyday life situations Introvert's are going to be most happy when put in situations/settings that do not cause them over-arousal. This may sound over-simplistic but happiness and positive well-being do not belong solely to highly sociable Extraverts. Some people just enjoy their own company as much as others.