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Adolescent Big Five personality and pubertal development: Pubertal hormone concentrations and self-reported pubertal status.

Van den Akker, Alithe L., ORCID 0000-0002-4981-5265. Department of Child Development and Education, Research Priority Area Yield, University of Amsterdam, Amsterdam, Netherlands, [email protected] Briley, Daniel A.. Department of Psychology, University of Illinois at Urbana–Champaign, Champaign, IL, US Grotzinger, Andrew D.. Department of Psychology, University of Texas at Austin, Austin, TX, US Tackett, Jennifer L.. Department of Psychology, Northwestern University, Evanston, IL, US Tucker-Drob, Elliot M.. Department of Psychology, University of Texas at Austin, Austin, TX, US Harden, K. Paige. Department of Psychology, University of Texas at Austin, Austin, TX, US

Van den Akker, Alithe L., Department of Child Development and Education, Research Priority Area Yield, University of Amsterdam, Nieuwe Achtergracht 127, Amsterdam, Netherlands, [email protected]

Developmental Psychology, Vol 57(1), Jan, 2021. pp. 60-72.

Dev Psychol

US : American Psychological Association

0012-1649 (Print) 1939-0599 (Electronic)

English

personality, puberty, testosterone, progesterone, DHEA

In early adolescence, levels of conscientiousness and agreeableness have been found to temporarily decrease, with levels of neuroticism increasing, indicating a dip in personality maturation. It is unknown whether these changes are related to the process of puberty, a major developmental milestone with numerous changes for children. Here, we first replicated the dip in personality maturity in early adolescence (N = 2640, age range 8– 18, 51% girls, 65% non-Hispanic white, 21% Hispanic/Latino, 10% African American, 9% other, roughly 33% of families received means-tested public assistance) and tested associations between the Big Five personality dimensions and pubertal development and timing across late childhood and adolescence (n = 1793). Pubertal development was measured using both hormonal assays (DHEA, testosterone, and progesterone) and self- reports of secondary sex characteristics. Of hormonal measures, only higher DHEA concentrations were associated with lower conscientiousness and openness. Nonparametric moderation analyses using LOSEM indicated Complex Age × Sex interactions involving all three hormones. Self-reported pubertal development was associated with lower extraversion, conscientiousness, agreeableness, and openness. More

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advanced pubertal timing was also related to lower levels of extraversion, conscientiousness, and agreeableness. All associations were small. As some evidence was found for small associations between pubertal development and lower levels of conscientiousness and agreeableness, a dip in personality maturation in these personality traits may be partly due to pubertal development in early adolescence. Overall, results did not indicate that pubertal development was the primary explanation of the maturity dip in adolescent personality. Many small influences likely accumulate to explain the dip in personality maturity in early adolescence. (PsycInfo Database Record (c) 2020 APA, all rights reserved)

Journal Article

*Adolescent Development; *Conscientiousness; *Personality Development; *Puberty; Hormones; Progesterone; Early Adolescence

Personality Traits & Processes (3120)

Human Male Female

US

Childhood (birth-12 yrs) School Age (6-12 yrs) Adolescence (13-17 yrs) Adulthood (18 yrs & older) Young Adulthood (18-29 yrs)

Big Five Inventory Pubertal Development Scale DOI: 10.1037/t06349-000

Sponsor: National Institutes of Health, US Grant Number: R01HD083613; R01HD092548 Other Details: Texas Twin Project Recipients: No recipient indicated

Sponsor: Jacobs Foundation Other Details: Research fellowships Recipients: Briley, Daniel A.; Tucker-Drob, Elliot M.; Harden, K. Paige

Empirical Study; Quantitative Study; Twin Study

Electronic

Journal; Peer Reviewed Journal

Accepted: Nov 1, 2020; Revised: Oct 12, 2020; First Submitted: Nov 26, 2019

20201231

American Psychological Association. 2021

http://dx.doi.org.ezp.waldenulibrary.org/10.1037/dev0001135

dev-57-1-60

2020-99409-002

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Database: APA PsycArticles

Adolescent Big Five Personality and Pubertal Development: Pubertal Hormone Concentrations and Self-Reported Pubertal Status

By: Alithe L. Van den Akker Department of Child Development and Education, Research Priority Area Yield, University of Amsterdam; Daniel A. Briley Department of Psychology, University of Illinois at Urbana–Champaign Andrew D. Grotzinger Department of Psychology, University of Texas at Austin Jennifer L. Tackett Department of Psychology, Northwestern University Elliot M. Tucker-Drob Department of Psychology, University of Texas at Austin; Population Research Center, University of Texas at Austin K. Paige Harden Department of Psychology, University of Texas at Austin; Population Research Center, University of Texas at Austin Acknowledgement: OSF link: https://osf.io/jgfqp/?view_only=d21e101898c64ab6b7478df003b40cf8.

The Texas Twin Project is supported by National Institutes of Health (NIH) Grants R01HD083613 and R01HD092548. Daniel A. Briley, Elliot M. Tucker-Drob, and K. Paige Harden are additionally supported by Jacobs Foundation research fellowships.

Note: Sara Jaffee served as the action editor for this article.—EFD

Big Five personality characteristics develop in the direction of increasing maturity across adulthood, with mean levels of agreeableness and conscientiousness increasing and neuroticism decreasing in the population (Roberts et al., 2006). However, during early adolescence these same personality traits appear to temporarily change in the opposite direction, becoming less mature before increasing in maturity again (Göllner et al., 2017; Luan et al., 2017; Soto et al., 2011; Van den Akker et al., 2014). These temporary declines in personality maturation have in turn been associated with adolescents’ behavioral and emotional problems (Van den Akker et al., 2010). At present, it is unknown what causes this temporary disruption of personality maturation, but pubertal development is a strong candidate factor (Soto & Tackett, 2015). Here, we test whether we can replicate the temporary dip in personality maturation using a large (N = 2640), cross-sectional (age range primarily 8–18 years) sample. Next, we test whether markers of pubertal development, hormone concentrations and self-reports of secondary sex characteristics are associated with personality. As most pubertal development takes place between 10 and 15, it may explain a dip in personality maturation in this age range.

Pubertal Development and Personality Maturation: Hormonal Concentrations

Individual differences in characteristic ways of thinking, feeling, and behaving that are relatively stable across time and situations, or personality traits, can be captured by five overarching personality dimensions: Extraversion, Agreeableness, Conscientiousness, Neuroticism, and Openness to Experience (Goldberg, 1990). The same “Big Five” dimensions describe personality traits in childhood and adolescence as in adulthood, allowing for the investigation of the development of these traits across the life span (Shiner & Caspi, 2003). Investigations of mean-level personality development across early and middle adulthood have converged on the finding that, for the population as a whole, levels of conscientiousness and agreeableness increase, whereas

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levels of neuroticism decrease (Roberts et al., 2005). To explain this phenomenon, it was hypothesized that taking on adult social roles (i.e. starting a paid job and entering a stable romantic relationship), something that most young adults do during this period, could explain why the population as a whole tended to increase in those characteristics that are necessary to be successful in these roles (Roberts et al., 2005). Mean-level development thus tends to be aimed at increasing maturity during early adulthood. As levels of extraversion and openness do not show a consistent pattern of maturation in adulthood, with openness remaining fairly stable and some aspects of extraversion increasing and others decreasing, they are not central to the maturity principle (Roberts et al., 2005).

When investigations of mean-level development of the Big Five personality dimensions were extended to earlier ages, several findings indicated trends in the opposite direction. Although similar trends to early adulthood were already visible in later adolescence, during early adolescence (between ages 10 and 15) several findings indicated that youths’ personality traits were actually becoming less mature than they were before, with evidence for decreases in agreeableness (Göllner et al., 2017; Luan et al., 2017; Soto et al., 2011; Van den Akker et al., 2014) and conscientiousness (Borghuis et al., 2017; Göllner et al., 2017; Soto et al., 2011; Van den Akker et al., 2014) and increases in neuroticism for girls specifically (Borghuis et al., 2017; Luan et al., 2017; Soto et al., 2011; Van den Akker et al., 2014). As lower levels of conscientiousness and agreeableness are important predictors of externalizing problems, and neuroticism is a predictor for internalizing problems (Tackett, 2006), these changes have important implications for adolescents’ psychological and behavioral adjustment. During this developmental period, incidence of problems such as delinquency (Moffitt, 1993) and depression (Bongers et al., 2003) increase, and the dip in personality maturation may explain these increases. Indeed, these changes have been found to be associated with increased adjustment problems in youth (Van den Akker et al., 2010). Therefore, it is important to understand what may be driving the disruption of personality maturation in early adolescence.

Although contemporary personality theories vary in the relative importance they place on intrinsic maturation versus social influences in explaining mean-level personality development (e.g., Costa & McCrae, 2006; Roberts et al., 2006), findings of small genetic influences on intraindividual personality changes for young adults (Hopwood et al., 2011) and adolescents (Kawamoto & Endo, 2019) indicate that biological processes do play a role. Important biological changes that coincide with the dip in personality maturation during the transition to adolescence are the hormonal changes associated with pubertal development. The onset of puberty in humans, typically occurring in childhood when children are between 6 and 8 years of age, is adrenarche. Adrenarche is characterized by a rise in the adrenal hormone dehydroepiandrosterone (DHEA), as a result of maturation of the hypothalamic-pituitary-adrenal (HPA) axis, causing pubic hair to grow and body odor to develop (Havelock et al., 2004). Approximately two years later, as children enter adolescence, gonadarche introduces the increase of gonadal hormones, including testosterone and progesterone (Hiort, 2002), which are responsible for the development of secondary sex characteristics (Dorn, 2006). The process of pubertal maturation is completed approximately four to five years later, around age 15 (Dahl et al., 2018).

Pubertal development could be related to a disruption in personality maturation because the rise in concentrations of pubertal hormones affects brain function and structure (Blakemore et al., 2010). These neurological changes produce changes in emotion, cognition, and behavior. These neurological changes produce changes in emotion, cognition, and behavior. DHEA associated neurological changes have been connected to emotional processing (Whittle et al., 2015). Similar findings have linked testosterone to increased risk-taking behavior (Braams et al., 2015) and progesterone to emotional processing and response inhibition (for a review, see Toffoletto et al., 2014). These changes are likely reflected in more stable changes in patterns of thinking, feeling, and behaving, rather than mere short-lived state changes. Therefore, we can expect these to be reflected in personality trait changes. The effects of rising concentrations of pubertal hormones can be expected to be

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especially likely to play a role in personality development in early adolescence as it has been proposed that youth likely adapt to the rises in hormonal concentrations after some time (Buchanan et al., 1992).

Although we know of no studies investigating pubertal hormones in relation to the broad Big Five personality dimensions, some evidence for the possibility of pubertal hormone concentrations impacting narrower traits than the Big Five are available. Testosterone has been associated with social dominance (Rowe et al., 2004; Tremblay et al., 1998), which is a facet of extraversion (John & Srivastava, 1999), as well as sensation seeking (Harden et al., 2018), which is related to both high extraversion and low conscientiousness (Mann et al., 2017), and irritability (Olweus et al., 1980), a facet of neuroticism (John & Srivastava, 1999).

Pubertal Development and Personality Maturation: Self-Reported Pubertal Development Status

Although changes in physical characteristics associated with pubertal development are initiated by hormonal changes, measures of pubertal development status derived from physical characteristics are only moderately associated with measures of hormonal concentrations (Shirtcliff et al., 2009). Pubertal development status derived from physical characteristics may be associated with personality changes over and above hormonal concentrations because physical characteristics are more closely tied to social experiences that accompany pubertal development (Blakemore et al., 2010). For instance, physical changes associated with pubertal development may indicate to the social environment that children are becoming more mature. With increased perceptions of maturity, expectations regarding mature (i.e. well regulated, independently planned and executed) behavior may also increase. Consequently, although adolescents’ personalities may still be maturing, demands placed on them by their environment (e.g., parents, teachers) may increase even more strongly. The result of this discrepancy between adolescents’ actual maturation on the one hand and expectations of their social environment on the other may be that adolescents appear to be decreasing in maturity (Denissen et al., 2013). For instance, even though children might be becoming more conscientious, when they are suddenly expected to keep track of homework, clean their own rooms, and make sure they are on time for sports lessons, they may forget some tasks on their to-do list. Children may receive negative feedback from parents or teachers and may view themselves as becoming less conscientious. This maturation disparity, or the gap between expectations and underlying capabilities, may diminish as adolescents’ underlying psychological capabilities develop to match their changing physical appearance. Therefore, more advanced pubertal development status derived from physical characteristics may be related to lower personality maturity especially in early adolescence.

Although we know of no studies examining associations between the Big Five dimensions and pubertal development status, a few studies regarding other personality traits are available. Pubertal development status at age 12 has been associated with both positive and negative urgency, traits that describe a tendency to react rashly in response to positive versus negative emotion respectively (Gunn & Smith, 2010). Both these traits are associated with high neuroticism and low conscientiousness and agreeableness, or a less mature personality (Cyders & Smith, 2008). Constraint, which can be considered a combination of traits associated with conscientiousness and openness to experience, (Church, 1994) has been found to be associated with pubertal development differently for boys and girls (Schissel et al., 2011). For girls, pubertal development was negatively related with constraint during earlier stages of puberty but unrelated at later stages. For boys however, pubertal development was positively associated with constraint during early stages of puberty, with no association thereafter. Planning and perseverance, two other subcomponents of conscientiousness (John & Srivastava, 1999), have been found to be unrelated to pubertal status (Gunn & Smith, 2010), as has impulse control (Castellanos-Ryan et al., 2013). Two other studies found that pubertal status was unrelated to traits related to positive emotionality (a facet of extraversion) and negative emotionality (a facet of neuroticism; Canals et al., 2005; Schissel et al., 2011).

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Goals of the Current Study

Although pubertal development is a strong candidate factor in explaining decreases in personality maturity in early adolescence, no study has previously examined associations between pubertal development, as assessed either by hormonal concentrations or pubertal development status derived from physical characteristics, and Big Five personality dimensions. It is important to understand what is driving these personality changes to understand how to best support adolescents during this time.

In a preliminary step, we examined mean-level trends of self-reports of the Big Five personality dimensions in a large, cross-sectional sample with an age range from 8 to 18 years (N = 2640) to investigate whether they were in line with a temporary disruption in personality maturation in early adolescence. Next, we examined associations between the Big Five personality dimensions and pubertal development. First, we examined associations with pubertal hormone concentrations in hair samples (i.e. DHEA, testosterone, and progesterone, n = 1793). Hair sampling is a recently developed, noninvasive method of collecting longer-term free hormone output (Gao et al., 2016). If rising pubertal hormone concentrations play a role in explaining a dip in personality maturation in early adolescence, we would expect that hormone concentrations would be associated with lower personality maturity as evidenced by lower levels of agreeableness and conscientiousness and higher levels of neuroticism. These effects might be stronger for younger adolescents as pubertal development is a process that adolescents may adapt to over time. We also examined associations with Extraversion and Openness to Experience to gain a complete picture of associations with the Big Five. These analyses were exploratory. Next, we examined associations of the Big Five personality dimensions with pubertal development status as measured by youth self- report of physical characteristics. For pubertal development status as derived by physical characteristics, we expect similar associations with the personality dimensions as for the hormone concentrations. Finally, we examined whether either pubertal hormone concentrations or pubertal development status derived from physical characteristics were uniquely associated with the Big Five. Moderation by sex was examined for the associations.

Method

All analytic plans were preregistered on OSF (https://osf.io/t52k8/? view_only=75c8ef2395e6423ca36941f7788bb8fb).

Sample The sample included 2640 participants from 1,102 families (49% boys) from the Texas Twin Project (Harden et al., 2013). Adolescent mean age was 13.64 years (SD = 2.93, range = 6.94–21.29 years). Over 94% of the sample was between the ages of 8 and 18 years, and we therefore base our inferences on this age range to avoid problems of overextrapolation. Sixty percent of the adolescents identified as non-Hispanic white, 21% as Hispanic/Latino, 10% as African American, and 9% as another race/ethnicity. Approximately a third of sibling pairs were monozygotic twins, with the remaining pairs being dizygotic twins. For the purposes of the current study, we did not perform any family based analyses. Instead, we analyzed the data at the individual-level and corrected for the nonindependence of drawing observations from the same family. A subset of the sample only provided self-reports on personality (n = 847). These participants were recruited prior to the introduction of hair sampling into the research protocol and typically completed mailed or online surveys rather than participating in the laboratory setting. The sampling frame was students in K-12 public schools for these participants. The rest of the sample provided both self-reports of personality and pubertal development, and pubertal hormone samples (n = 1793, from 771 families, 43% boys). The sampling frame was students in 3rd-12th grade public schools for these participants due to the in-lab nature of the data collection. Of this subsample, the average age was 12.45 years (SD = 2.84, range = 7.8–19.47 years). Participants who only had personality data and not hormone data tended to be younger due to the differences in the sampling frame but did not differ meaningfully on personality

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(average absolute value of Cohen’s d = .05). This result is consistent with the missing data being due to the design of the study rather than systematically on the basis of key study variables. A total of 20 additional participants were omitted due to some sort of disorder that would affect hormone levels (e.g., hypothyroidism), and an additional 51 participants were omitted due to use of hormonal birth control. The Texas Twin Project started recruiting participants from public schools in Austin, TX, Houston, TX, and surrounding areas in 2012, with data collection in Austin ongoing.

The Texas Twin Project subprojects were approved by the Institutional Review Board of the University of Texas as projects 2009–12-0040 (“A Sibling and Twin Study of Healthy Development in Children and Adolescents”), 2011– 11-0066 (“A Twin Study of Healthy Development in Infants and Young Children”), 2011–11-0067 (“Genetic Influences on Adolescent Decision-Making and Alcohol Use”), 2013–02-0011 (“The Genes and Development Study”), 2014–11-0021 (“Cortisol, Socioeconomic Status, and Genetic Influence on Cognitive Development”), and 2016–01-0004 (“Genetic & Hormonal Influences on Adolescent Decision-Making”).

Measures Personality

Adolescents provided self-reports on the 44 items of the child version of the Big Five Inventory (BFI; John et al., 2008). Participants were asked to indicate on a 5-point Likert-type scale ranging from 1 (strongly disagree) to 5 (strongly agree) how much they agreed that the item described them. The BFI assesses extraversion with 8 items (example item: “is talkative”), neuroticism with 8 items (example item: “can be tense”), conscientiousness with 9 items (example item: “does a thorough job”), agreeableness with 9 items (example item: “starts quarrels with others”), and openness to experience with 10 items (example item: “has an active imagination”). Individual item responses were corrected for acquiescence by subtracting person-specific means, and extreme responding by dividing scores by person-specific standard deviations of responses to pairs of items with opposite implications for personality (e.g., “is talkative” vs. “tends to be quiet”), prior to computing mean scale scores (Soto et al., 2008). Acquiescence is reflected by participants’ tendency to agree with items with differing implications for personality, and extreme responding is reflected by participants’ tendency to use either pole of the scale. Cronbach’s alphas in the current sample were: Extraversion = .80, Agreeableness = .75, Conscientiousness = .78, Neuroticism = .72, and Openness = .70.

Pubertal Hormones

DHEA, testosterone, and progesterone concentrations were derived from hair samples summing 3 mm in diameter from the posterior vertex of the scalp, representing an accumulation of hormones over 3 months. Participants were instructed not to use any hair products that were not rinsed out of the hair the day of the appointment. Hair samples were stored at room temperature before being shipped to Dr. Clemens Kirschbaum’s laboratory at Technical University Dresden, where they were analyzed using liquid chromatography-tandem mass spectrometry (Gao et al., 2013). The lower limit of detection was 0.1 pg/mg. There were 459 samples below this threshold for testosterone, 365 for progesterone, and 172 for DHEA. A winsorizing procedure was used to replace extreme values by the highest observed score within 3 standard deviations of the sample mean. This procedure replaced a total of 12, 9, and 15 observations for testosterone, progesterone, and DHEA, respectively. As all hormones were positively skewed, these variables were log-transformed to approximate normal distributions and then standardized. These procedures match previous publications using this data (Grotzinger et al., 2018) and our preregistration plan.

Self-Reported Pubertal Development

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Adolescents provided self-reports on the Pubertal Development Scale (PDS; Petersen et al., 1988). All adolescents rated five items on a 4-point scale ranging from 1 = not yet begun to change to 4 = finished changing with an option to respond I do not know, which was recoded as missing. Boys and girls all rated items about growth in height, growth of body hair, and changes in skin-appearance, with girls additionally indicating breast growth and menarche (1 = no and 4 = yes to maintain scaling with other items), whereas boys rated growth of facial hair and deepening of voice. The mean of these items was used as the final pubertal development score.

Analysis Plan First, to examine nonlinearities in mean-level age trends of the Big Five, indicating a disruption in personality maturation, we used nonparametric local structural equation models (LOSEM; Briley et al., 2015; Hildebrandt et al., 2016) to provide a nonparametric picture of age-trends in the key outcomes considered in this report (see participants section for details). The use of LOSEM is similar to the use of LOESS plots as an extension of regression analysis (Cleveland & Devlin, 1988). We fit locally weighted models with different focal ages from age 8 to 18 years in .1 increments. For example, when a model with age 8 years is the focal age, data near age 8 years is weighted most strongly, and data near age 18 years is weighted less strongly. Importantly, all models make full use of the entire dataset, and no arbitrary subsetting of the data is necessary. We chose 18 years as the upper bound of our analysis frame because very few observations with age greater than 18 were included in the dataset, and we did not want to extrapolate beyond our data coverage. All personality measures were standardized relative to the full sample mean and standard deviation to provide a more intuitive metric, and only for these models, the variables were not ipsatized to maintain the between-person metric of the scales.

To examine if more advanced pubertal development is associated with lower personality maturity, especially in early adolescence, we first examined associations between pubertal hormones and the Big Five personality dimensions, including hormone by sex interactions. To examine whether the associations were stronger in early adolescence than in later adolescence, we again estimated nonparametric LOSEM. In these models, effects of pubertal hormone concentrations, as well as interactions between pubertal hormone concentrations and sex, were tested for separate points across the age range in the sample (ages 8 to 18, with .1 year intervals). Given the marked discontinuities of pubertal development in this age range, we anticipated that nonlinear trends may be found. Next, we examined associations between self-reported pubertal development and Big Five personality dimensions. Sex and self-reported pubertal development by sex interactions were included in this model. To examine pubertal development by age interactions, we estimated regression models including linear and quadratic effects of age and pubertal development status by age interaction. It is important to note that including main effects of age necessarily changes the interpretation of the pubertal development status to mean pubertal development status relative to same-age peers, or “pubertal timing” (Marshall & Tanner, 1969). Therefore, for both the hormone concentrations and the pubertal development status, we also report results of models that do not include age. Finally, to examine whether pubertal hormones and pubertal development status derived from physical characteristics were uniquely associated with the personality dimensions, we included all variables in a single model.

All models were estimated in Mplus Version 7.31 (Muthén & Muthén, 1998–2015), with estimation type = complex to account for the nested structure of the data with individual twins nested within families. Missing data were h

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