Maigan Wipfli : Lived Experiences of Introverts
Odilon Redon - The reader, 1892
Maigan Wipfli
Personality Trait Theory: The Extraversion-Introversion Dimension
The notions of introversion and extraversion first gained popularity in the 1920s with the release of Jung's Psychological Types (1926). (...)
Extraversion and introversion are fundamental components of the theory, constructs at opposing ends of a spectrum representing orientation toward life. Each point along the spectrum indicates a different level of extraversion or introversion. Jung and others theorized that all of us fall at some point along this spectrum. Individuals on the extraverted side have more of an outward orientation. Such individuals "tend to focus their perception and judgement on people and objects". Their attitude reflects "an action-oriented . . . way of meeting life" characterized by sociability. For them, the external world brings greater energy. It is a source of renewal. For introverts, on the contrary, the primary source of strength is within. They "are oriented primarily toward the inner world" of concepts and ideas.
The introverted attitude is characterized by detachment and by enjoyment of solitude and privacy. Introverts are more likely to feel energized by withdrawing into solitude; thoughts and feelings are paramount in their lives. While each orientation has its own singular drawbacks and advantages, the theory does not make claims as to the value of one over the other.
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Characteristics of Extraversion and Introversion
Three fundamental characteristics associated with the traits of extraversion and introversion have surfaced in the research literature: sensory-processing sensitivity, reflectivity (versus responsiveness), and external reward sensitivity. These characteristics seems to undergird the traits, and mirror or shed light on the traits themselves as well as the collections of sub-traits of which these broader traits are comprised.
Sensory-Processing Sensitivity
A growing body of literature suggests a moderately strong, positive correlation between introversion and what Aron has referred to as "sensory-processing sensitivity"--i.e., level and ease of arousal in response to external stimuli. The idea is that sensory information, generally speaking, stimulates introverts more than it does extraverts. Moreover, introverts are likely to become over-aroused by stimuli that extraverts may deem quite normal, such as lively social interactions.
In a later work, Aron reported that the greater sensitivity displayed by introverts is evidenced "at all levels of the nervous system," citing research that ties extraversion-introversion levels to sensory processing sensitivity via measures of skin conductance, reaction times, and evoked potential, as well as to subcortical functioning and differences in cortical processing. One of the effects of the greater sensory-processing sensitivity commonly seen in introverts could be their quieter and more solitary ways: "For highly sensitive people, avoiding the intense stimulation of social interaction with strangers or in groups can be an effective strategy to minimize opportunities for uncomfortable stimulation".
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Opt and Loffredo (2000) drew a similar conclusion to that of Aron, emphasizing--perhaps contrary to popular opinion--that a tendency or need among introverts to avoid in-person communication was not at all problematic. The authors further proposed the need to examine "the kinds of communication skills and styles being taught in our education system," asking "Are we teaching the preferences of the extravert ?. Opposed to the "preferences of the extravert" would be the (nonetheless healthy and psychologically sound) preferences of the introvert for things like solitude or quiet over livelier social interaction. While the two opposing preferences may be tied to variation in sensory-processing sensitivity, research suggests that they also have to do with higher levels of reflectivity.
Reflectivity vs Responsiveness
The quality of greater reflectivity or introspection commonly observed in introverts is otherwise described as "the innate preference for a more thorough subjective processing of information regarding all objects". It is a preference to reflect before acting, a stringency in the criteria for responding. (...)
Later research on personality differences and brain functioning substantiates such findings. Johnson et al. measured cerebral blood flow using positron emission tomography scans from "healthy normal" subjects classified as extraverts or introverts. The subjects "were free to think about anything" while being scanned, "providing a picture of the activity of the undirected and uncensored mind"). (...) Results add support to the notion that introverts tend toward reflectivity, mulling the past and planning the future, while extraverts tend toward responsiveness, living and acting in the moment. These different propensities may surface not only in the activities extraverted and introverted college students find rewarding but also in the processes whereby they become involved on campus.
The quality of reflectivity also may interact with that of sensory-processing sensitivity for heightened effect in certain settings. That is, "numerous or novel objects" could "place high demands on the sensitive person," who is strongly affected by external stimuli. Yet "being so affected by objects creates a desire . . . to process all of this sensory information before trying to respond". So, being sensitive, the introvert in a busy, novel, or crowded setting may experience greater arousal from the (seemingly intense) sensory input. Due to her reflective inclination, she may then feel the added inclination to process, to inspect, or to make sense of this overwhelming amount of input prior to responding to it. It is no wonder the introvert typically finds comfort in calmer environs, and it remains to be seen if and how the personality traits of sensory-processing sensitivity and reflectivity are associated with her experience of college life.
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Sensitivity to Reward, Positive Affect, and Sociability
A third characteristic associated with the E-I dimension is sensitivity to external reward, closely linked with incentive motivation. While greater reflectivity and sensory-processing sensitivity highlight the introvert's quieter tendencies, sensitivity to reward or incentive motivation may largely account for the sociability and positive affect commonly linked to extraversion.
Incentive motivation is defined in terms of "the anticipation, vigor, and extent to which rewarding stimuli in the environment activate appetitive emotional states". Incentive motivation is thus closely associated with the simpler, common-sense notion of external reward sensitivity -- the heightened perception, influence, or appreciation of rewarding stimuli or of the prospect of rewarding stimuli that are found in one's external environment.
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It appears that some of the distinguishing characteristics of extraversion are sensitivity to rewards (closely tied to incentive motivation), and indirectly, positive affect and sociability. From what the research suggests, reward sensitivity largely accounts for positive associations observed between extraversion and both positive affect and sociability. In the college setting, extraverted students may be more sensitive to the rewards that stem from social interaction or networking on campus.
This reward sensitivity could also lead extraverted students to seek more social interaction than their introverted counterparts and to thrive in highly social settings. Further, extraverts' greater display of positive emotionality is in line with findings from student involvement research suggesting that increased active and social involvement make for "happier," thriving students. Such findings may implicitly reinforce a converse (and perhaps invalid) association between quieter involvement activities and less happy students.
To briefly recap the section, research suggests that introverts exhibit greater reflectivity and higher sensitivity to external stimuli, while extroverts show heightened sensitivity to external rewards and, relatedly, greater positive affect and sociability. Introverts may be hard-wired to inspect and cautious to act. They can easily become over-aroused by external stimuli and are less affected by the prospect of external rewards. Extraverts have a propensity to take action. They are not as moved by sensory stimulation and may, as a result, prefer higher levels of external stimuli than their introverted counterparts. Extraverts' s ensitivity to rewards is a strong motivator for them to engage in social settings, and it elicits their positive affect.
Beyond giving superficial descriptions of personal preferences, the labels suggest corresponding fundamental characteristics associated with how people act, how their brains function and are structured, and how their bodies and minds respond to various stimuli.
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Society and Culture
McCrae and Terraciano (2005) measured "aggregate personality" in terms of the "assessed mean personality trait levels of culture members" (p. 408). Data from college students representing 51 cultures worldwide led the authors to conclude that extraversion was higher on average in nations whose value systems corresponded with Westernized cultures. These cultures emphasize individualism rather than collectivism, "self-expression rather than survival . . . and high subjective well-being". The findings coincide with prior research demonstrating that average levels of extraversion are higher among Europeans than among Asians or Africans.
Based on several factors -- including the link observed between self-expression and extraversion; the predominance of both in Western societies; and the rapid westernization of the modern world -- McCrae and Terraciano (2005) predicted that overall extraversion levels should increase in coming decades.
If extraversion levels are set to increase with the spread of contemporary Western values, this increase would follow a historical trend already observed within the U.S., one that perhaps reflects the initial emergence of those values. Twenge conducted a meta-analysis of 59 studies drawing data from the completed personality inventories of nearly 17,000 American college students. Data were collected in the years between 1966 and 1993. The correlation between year of data collection and extraversion scores was strong and positive, and not accounted for by demographic changes in the college-going population. This strong correlation suggested not an individual but a societal shift, i.e., a broad environmental effect on the prevalence of extraversion over time. The increase in extraversion accounted for between 14 and 19% of variance in the trait over the period reviewed.
Twenge hypothesize the shift to stem from things like increased family mobility and changes in child rearing that exposed children to greater social interaction; a shift in gender roles, with women acquiring greater assertiveness and public (i.e., social) presence; a move in the economy away from industry and toward service; and, significantly for the purposes of the current study, a change in schools, which "increasingly emphasized group work and social skills, recognizing that there are few jobs in the new economy that do not involve dealing with people".
Societal shifts serve as ample evidence to account for the increased prevalence of extraversion in recent decades: it's quite plausible that societal transformations have led - perhaps accidentally and not necessarily for the better - to the promotion of values that happen to be associated with extraversion. Twenge and others have argued that these extraverted values have become the norm in today's Western societies. We as a sociocultural group tend to favor the person of action, primed to respond, lively, affable, and enthusiastic in social settings.
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