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Abstract

A large number of studies have been conducted on the structure of Intellect, which is one of the facets of Openness/Intellect. However, far less is known about the development of Intellect and the impact of external influences such as critical life events. In the present study, we investigated socialization and selection effects of Intellect in relation to the subjective perception of life events and self-efficacy. In a large German longitudinal sample of adolescents and emerging adults (N = 1477), we used mixed linear models to assess mean-level changes and moderating effects across three measurement occasions. We found significant change in Intellect but no evidence of the influence of experiencing a critical life event. Self-efficacy predicted mean levels and change over time in Intellect yet did not interact with perceptions of life events. Further research ideas are discussed.

Keywords

personality development intellect critical life events self-efficacy

Introduction

Cognitive abilities and their behavioral implementations have always been a major topic as well as a compelling one for researchers. The personality trait Intellect reflects one of the foremost constructs that can be used to explore the interplay of dispositional gifts, situational properties, and the prediction of cognitive performances. According to the Big Five personality structure, Intellect can be classified as a subdimension (or facet) of the personality factor of Openness/Intellect (DeYoung, 2014; Goldberg, 1992; Costa & McCrae, 1992). The compound label Openness/Intellect identifies an empirically derived dimension that displays individual differences and describes processes that reflect cognitive and perceptual exploration (see DeYoung, 2014, for a review). Conceptually, Intellect is a distinct construct that encompasses attributes such as smart, clever, curious, and enjoys problem-solving and learning, and it can be considered the personality counterpart of cognitive abilities (Costa & McCrae, 1992; DeYoung, 2014; Goldberg, 1992; Mussel & Spengler, 2015). Whereas cognitive abilities refer to ability, which is the “can do” aspect of performance, Intellect refers to the personality trait and motivational component, namely, the “will do” or “typically do” aspect (see Mussel, 2013, for a review). For example, forasmuch as intelligence is a term that is used for an individual’s ability to acquire and then apply skills and knowledge, Intellect is the faculty of objectively understanding and reasoning about abstract matters.

Several constructs that have been proposed from different theoretical backgrounds have been identified as distinct indicators of Intellect. These include the facets of Openness to Ideas (Costa & McCrae, 1992), typical intellectual engagement (Goff & Ackerman, 1992), need for cognition (Cacioppo et al., 1996), and epistemic curiosity (Litman & Mussel, 2013). However, these constructs often overlap considerably and can all be assumed to indicate Intellect (Mussel, 2010). Others have assumed a broader conceptualization of Intellect, thereby including a “can do”-component in addition to cognitive motivation. For example, the Big Five Aspect Scale (BFAS, DeYoung et al., 2007) includes ability traits such as self-reported intelligence to measure Intellect. Hence, the debate about a shared definition and the integration of research findings is still ongoing (e.g., Mussel, 2013; Fleischhauer et al., 2010; von Stumm et al., 2011).

In a narrower sense, we focus on the previously mentioned “will do” aspect, which is related to the cognitive motivation of behaviors such as problem-solving, thinking, information seeking, learning, and creativity (Mussel, 2013). Referring to these indicators, studies have shown that Intellect predicts professional success, organizational outcomes, academic investment, and performance (Mussel et al., 2011; von Stumm et al., 2011). Thus, people high in Intellect are likely to obtain more job knowledge, seek new information, appreciate complex information, show better coping styles when it comes to changes in the organization itself, and exhibit more creativity in team-building challenges (Arnone et al., 1994; Mussel et al., 2011). However, compared with the large number of studies on the structure and outcomes of Intellect, far less is known about the development of Intellect across the life course and its moderating factors (Strobel, 2021).

Intellect and life events

Research has supported the idea that personality is modifiable and can be changed due to environmental as well as internal influences (Geukes et al., 2018; Goldberg, 1992; Roberts & Mroczek, 2008). Regarding the development of trait Intellect, critical life events can play an important role because they have been shown to influence personality development via an interaction between person and environment (Bleidorn et al., 2018). Critical life events are referred to as “transitions that mark the beginning or the end of a specific status” (Luhmann et al., 2012, p. 594). Several studies have demonstrated not only that certain life events can sustainably affect personality traits (socialization effect), but also, on the basis of existing personality characteristics, that specific events are more likely and qualitatively different experienced than others (selection effect; Bleidorn et al., 2018; Jackson et al., 2012). Concerning assessments of critical life events, previous research has shown how important it is to differentiate between assessments of the mere occurrence versus the subjective perception of life events (de Vries et al., 2021; Luhmann et al., 2020).

The interaction between person and environment is also potentially relevant for the personality trait of Intellect. Particularly in adolescence and emerging adulthood, which are characterized by numerous changes and rapid developmental progress, critical life events can have a far-reaching impact (e.g., Bleidorn et al., 2018; Denissen et al., 2018; Pusch et al., 2018). Some of the most common events that occur during emerging adulthood are moving away from home, graduating from high school, and/or starting further academic education (Arnett, 2000, 2007). Because these events are associated with mastering unknown challenges and dealing with cognitively demanding problem-solving strategies, it can be assumed that Intellect will increase during this time. This was previously found to be true for Openness/Intellect: When students were put into novel situations such as studying abroad for an extended period of time and had to adapt to an entirely new culture, their Openness/Intellect levels increased (Zimmermann & Neyer, 2013). Strobel et al. (2017; 2018) found that the number of experienced positive critical life experiences in the past predicted levels in need for cognition and openness to ideas. As Intellect contains an evaluative component regarding epistemic behavior, it can be speculated that subjective perceptions of the life event with regards to valence are a crucial factor to consider regarding trait trajectories. Particularly, perceiving a critical life event that encompasses a cognitive challenge as more positively, might reflect that the challenge was mastered successfully or that it resulted in personal growth or learning. This, in turn, might lead to altered appraisals of challenging situations that require thinking and learning which may ultimately be reflected in increasing levels of Intellect.

With regard to selection effects, different levels of Intellect could also influence how people process critical life events. That is, major life events might be perceived more positively when adolescents and emerging adults encompass high levels of Intellect because they can rely on their intellectual skills and react to abstract matters and new situations more quickly—thus mastering external stressors more easily. Accordingly, DeYoung et al. (2007) found that Intellect was negatively related to Neuroticism and served as a protective factor against the experience of negative emotions. Bye and Pushkar (2009) found that need for cognition predicted positive experiences associated with retirement, which was mediated by frequency of cognitive activity. Therefore, individuals with low levels of Intellect may evaluate critical life events more negatively because of insecurities and possible ambiguity experienced during the event and positive life events more positive due to active thinking and problem-solving behavior. Likewise, adversely experienced life events could lead to a further decrease in Intellect. Accordingly, a decline of Openness/Intellect was previously found after experiencing critical life events such as job loss, separation, or divorce (Lockenhoff et al., 2009; Specht et al., 2011).

Taken together, research has emphasized that Openness/Intellect can and does change throughout the lifespan due to external and internal influences, and there is evidence to suggest the same on the facet level for Intellect. Nevertheless, the latter has undergone far less investigation, and even less research has been conducted to assess the underlying processes that determine the development of Intellect.

The moderating role of self-efficacy

With respect to the interdependencies of environmental influences and the development of Intellect, the current study was further aimed at investigating individual differences in the processing of critical life events in relation to Intellect. A construct that is strongly related to the appraisal of life events are core beliefs, which are described as mental representations that individuals hold about themselves, others, and the world in general (Dweck, 2017; Mussel, 2023). Self-efficacy constitutes such a core beliefs and describes a person’s expectation that they will be able to successfully perform desired actions on the basis of their own competencies and sustain or regulate cognitive, motivational, and affective processes (Bandura, 1997).

Self-efficacy beliefs have been shown to correlate with subjective well-being, health, academic performance, and psychosocial outcomes across different samples and cultures (e.g., Bandura, 1997; Caprara & Zimbardo, 2004; Benight & Bandura, 2004; Luszczynska et al., 2009). People who believe they can count on their abilities to exercise control over events tend to deal more effectively with potential stressors, adapt more easily to ambiguous situations, and manage the demands of everyday life with less distress (Bandura, 1997; Luszczynska et al., 2009; Maciejewski et al., 2000). Moreover, self-efficacy is not a static construct but is rather a characteristic that can be changed through behavior, by the external environment, or by internal personal factors, such as cognitive, affective, and biological events (Bandura, 1997).

Regarding critical life events, self-efficacy has been found to play an important role in terms of processing and coping. For example, self-efficacy mediated people’s cognitive responses to stressful life events such as earthquakes (Laks et al., 2013) or general traumatic experiences (Cieslak et al., 2008) and acted as a buffer against possible long-term consequences such as numbing, flashbacks, and fatigue (Benight & Bandura, 2004; Luszczynska et al., 2009) while promoting coping strategies like seeking social support and renegotiating the self (Laks et al., 2013). In other words, even though critical life events can interfere with the current stabilization of the self-system, individuals can play a proactive role in the adjustment process, and there is evidence that people high on self-efficacy tend to subjectively perceive difficulties and obstacles with less apprehension (Benight & Bandura, 2004; Cieslak et al., 2008).

With this in mind, we argue that self-efficacy should function as a moderator of the relationship between the development of Intellect and the perception of life events. Self-efficacy and Intellect have been found to be moderately related (Peterson & Whiteman, 2007). Additionally, as mentioned before, high levels of self-efficacy have the potential to buffer the perception of a particular life event as highly negative, for example, feeling that one has control over a situation instead of experiencing insecurity. Thus, adolescents and emerging adults high in self-efficacy might be able to deal with self-defining critical life events with less struggle and adjust to new circumstances more easily. We posit that this feeling of capability will then also influence the development of Intellect. Thus, people’s levels of Intellect might increase (decline) after they experience a positively (negatively) perceived life event due to high (low) levels of self-efficacy.

The present study

The present study aimed to investigate the development of trait Intellect in adolescence and emerging adulthood over three measurement occasions with regard to the influence of the perception of critical life events and underlying beliefs such as self-efficacy. Whereas previous studies on personality development have mainly been based on the broad concept of the Big Five, the present study expands knowledge on normative changes in personality on a facet level, also considering environmental influences. Hereby, our focus on the facet level enables a more granular investigation of specific hypotheses about triggers and external influences on the development of Intellect over time.

First, we investigated mean differences in Intellect and assumed that the personality trait Intellect would increase during adolescence and emerging adulthood due to engagement in developmental tasks which require attributes such as thinking, learning, problem-solving, and understanding abstract matters (Roberts et al., 2006).

Second, regarding socialization effects, we propose that life events influence the development of Intellect such that subjectively positively experienced critical life events should lead to an increase in Intellect. In this study, we focused on adolescents and emerging adults, who are in a stage in which they experience learning every day. When successfully applying cognitively demanding problem-solving strategies and, thus, perceive situations like graduating high school or moving away from home positively. Adolescents and emerging adults might seek out further developmental tasks to master – resulting in a further increase in Intellect. In turn, we propose that people with different levels of Intellect vary in their perceptions of critical life events. For instance, individuals with high levels of Intellect are more likely to employ effective problem-solving strategies, which can enhance their ability to maintain control in challenging situations. As a result, they might evaluate significant life events more positively. Conversely, individuals with low Intellect scores may have a more negative experience. For instance, when people struggle to grasp abstract concepts, they may feel insecure and uncertain during such events.

Third, we extended our theoretical approach by investigating if certain associations are different for different people and examine whether self-efficacy moderates the relationship between Intellect and the perception of life events. In particular, we analyzed whether perceived confidence in one’s own effectiveness of action functions as the key variable between the mastering of critical life events and the development of Intellect. Altogether, we investigated the development of Intellect in relation to the subjective perception of life events and the influence of self-efficacy.

Method

In the following, we report how we determined our sample size, all data exclusions, all manipulations, and all measures in the study (Simmons et al., 2021).

Sample and procedure

The current study used data from the German Personality Panel (Mussel, 2021) which is a longitudinal panel that we created by collecting data from a large German sample in cooperation with a German company that provides a nonprofit online career counseling test (berufsprofiling.de). On this test, participants are asked questions about their personality traits and vocational interests. Afterwards, they receive comprehensive feedback and advice about job opportunities and academic pathways after graduation.

The counseling test took place in the years 2016 and 2017, and we refer to this as T1 of the German Personality Panel. All participants who took this test agreed to be contacted again in the future. In September 2018 (measurement occasion T2) and in October 2019 (measurement occasion T3), we contacted these individuals and asked whether they would like to voluntarily participate in a longitudinal research study. Starting from T2, we included the variables of interest (perception of life events and self-efficacy) which are used in the present study. Participants took an online test lasting approximately 35 min and received financial compensation (EUR 5,--), and personal feedback on their results.

Sample

A total of N = 1526 individuals between 14 and 26 years of age (M = 17.39, SD = 2.37, 64.82% female) agreed to participate at T2 and filled out the online questionnaire. At T3, N = 1089 (69.62% female) participated in the study, out of whom N = 804 had also participated at T2. We did not include participants who were older than 21 years at the T1 (N = 75) of the German Personality Panel because we were interested in adolescents and emerging adults who were about to, for example, graduate from school and thus find themselves in a critical life period over the following measurement occasions. Accordingly, at the third measurement occasion (T3), 4% had not yet finished high school, 21% held a secondary school certificate, and a majority of 75% held a university entrance diploma. Out of these participants, 45% had already entered a university, whereas 32% were in a working position or had entered a traineeship.

Measures

Intellect

We used two indicators for Intellect. First, the Work-Related Curiosity Scale (WORCS; Mussel et al., 2012) which was applied at T1, T2 and T3, respectively. WORCS has been found to be highly correlated with Intellect in previous studies (e.g., r = .87; Mussel, 2013) and thus serves as a valid indicator (Mussel, 2010, 2013; Mussel et al., 2012). The WORCS is a 10-item measure, and responses are given on a 7-point Likert scale ranging from 1 (does not apply at all) to 4 (partly applies) to 7 (fully applies). Some of the items use a frame-of-reference approach with work-related item content. An example item is “I carry on seeking information until I am able to understand complex issues”. At T1, T2, and T3 the scale had a reliability coefficient ω between .86 and .90 ( $α$ = .84 – .88).

Second, we used the Intellect Scale (Mussel, 2013), which was applied at T2 and T3, respectively. The Intellect Scale is based on a definition of Intellect as a dispositional individual difference variable involving behavior, intentions, affect, attitudes, and mental processes related to intellectual performance, such as problem-solving, thinking, information search, learning, or creativity (Mussel, 2013). It comprises of 24 items, each of which relates to a process (seek, conquer) and content (think, learn, create) dimension. Responses are given on a 7-point Likert scale ranging from 1 (does not apply at all) to 4 (partly applies) to 7 (fully applies). Example items are “I enjoy solving complex problems” and “I take a lot of time so as to gain in-depth understanding of a new process.”. At T2 and T3 the scale had a reliability coefficient ω of .94 and .95 ( $α$ = .93 and .94).

The WORCS and the Intellect Scale correlated .89 and .91 at T2 and T3, respectively. Scores for the two indicators were aggregated at T2 and T3, respectively. Therefore, scores for the Intellect scale were scored according to the mean and standard deviation of the WORCS at T2.

Life events

The perception of critical life events was assessed at two measurement occasions, T2 and T3. On both measurement occasions, participants stated (1) which kind of event was experienced and (2) how they subjectively perceived the critical life event. However, the choice of life events slightly differed across measurement occasions.

At T2, we asked about two decisive major life events that are characteristic of the critical period between the late teens and young adulthood: graduating from school and moving away from home (Arnett, 2002; Lüdtke et al., 2011). Both events represent personal developmental milestones for the transition into adulthood and are typically associated with great educational/occupational challenges that imply searching for information, thinking, learning, and creativity, all of which are attributes that are strongly associated with Intellect. Moreover, e.g., in case adolescents and emerging adults did not (yet) experience either of the events, we provided an open text field in which participants could individually state a decisive critical life event that had occurred in the last year. For both cases, we assessed subjective perception through ratings that were given on a 7-point scale ranging from 1 (very negatively) to 7 (very positively). As we were solely interested in critical life events related to epistemic challenges, analyses were restricted to responses regarding graduating from school and moving away from home. If both occurred, ratings were averaged.

At T3, we slightly changed our operationalization due to improved knowledge about the assessment of life events (e.g., see Luhmann et al., 2020). Again, participants stated whether they had experienced a critical life event during the last year (between T2 and T3), but this time individuals could categorize the event using one of nine categories (e.g., romantic relationships; finance; health) and subsequently rate the valence of the major life event on two items (“The event was positive” and “The event was negative”). As for T2, we restricted our analyses to responses related to the two events regarding graduating and moving. If both occurred, ratings were averaged. A 7-point scale ranging from 1 (does not apply at all) to 7 (fully applies) was provided. Responses regarding negative valence were recoded and subsequently aggregated with ratings for positive valence.

Self-efficacy

To assess self-efficacy, we used the General Self-Efficacy Scale (GSE), a 10-item measure by Schwarzer & Jerusalem (1995). Responses are given on a 7-point scale ranging from 1 (does not apply at all) to 7 (fully applies). An example item is “I am confident that I could deal efficiently with unexpected events”. The test was administered at T2. The GSE was found to be highly reliable ( $α$ = .83, $ω$ = .85).

Statistical analyses

All statistical analyses were carried out in R 1.2.1335 (R Core Team, 2018) using the packages psych Revelle (2017) and lme4 (Bates et al., 2015). We analyzed the data using linear mixed effects models. These models are generally equivalent to latent change score models (Newsom, 2017), yet are more flexible for analyzing data with individually varying time points.

Raw data inspection

To improve data quality, we asked for self-reported diligence at the end of the survey at T2 and T3 (“Did you work conscientiously on the test?”). Participants were informed that their answer had no impact on their financial compensation. A total of 40 (3%) participants at T2 and 27 (2.5%) at T3 answered “No”. These participants were excluded. Moreover, we checked for missing values and outliers. Further, we excluded participants who had not participated on at least two measurement points. In total, a sample of 1564 individuals remained for the statistical analyses.

Hypotheses testing

Data were prepared in the long format. Intellect, assessed as the aggregated score from the WORCS and the Intellect Scale, served as the dependent variable and was scaled prior to the analysis. Fixed effects were estimated for age at T1; time difference between measurement occasions; self-efficacy; and valence of the critical life event. Age at T1 was included as a control variable to account for age differences at the start of the study and was centered prior to the analysis. Time difference between measurement occasions serves as fixed effect to investigate changes in Intellect across time. As T1 occurred within a time range of two years, it was included as continuous predictor and centered prior to the analysis. Self-efficacy was included as a level 2 fixed effect and scaled prior to the analysis. For the valence of the critical life event, scores obtained from T2 and T3 were included in separate analyses as continuous level 2 fixed effect following scaling. Finally, random intercept and slope were included for time differences between measurement occasions. Missing values were excluded case-wise.

Transparency and open science

The sample size was not determined in advance. Rather, the sample includes all participants available in the German Personality Panel. Participants responded to additional measures compared to that mentioned above. A description of all measures assessed at each measurement occasion is available at Mussel (2021). The study was preregistered after collection of the data, yet before conducting the analyses (de Vries, 2020a). The data and scripts are available via OSF (de Vries, 2020b). Compared to the preregistration, the data were analyzed with mixed linear models rather than latent change score models which allowed us, as suggested by an anonymous reviewer, to account for individually varying time points between measurement occasions T1 and T2.

Results

At T1, participants were between 14 and 21 years (M = 17; SD = 1.8). The time difference between T1 and T2 ranged between 0.7 and 2.7 years (M = 1.8; SD = 0.57), the time difference between T1 and T3 between 1.8 and 3.8 years (M = 2.8; SD = 0.58). At T2, 1030 out of 1349 (76 %) reported a critical life event relating to graduating or moving out. At T3, 512 out of 979 (53 %) did. For those who reported a critical life event at both measurement occasions (N = 316), the valence ratings for the two events were unrelated (r = −.01). All descriptive statistics and correlations can be found in Table 1.

Table 1.

Correlations and Descriptive Statistics Among Variables.

Variables	N	M	SD	Correlations
Variables	N	M	SD	1	2	3	4	5	6
1. Int-T1	1477	4.50	.94
2. Int-T2	1477	4.98	.80	.56***
3. Int-T3	1477	4.93	.84	.50***	.73***
4. SE-T2	1209	4.62	.82	.31***	.49***	.39***
5. CLE-T2	719	2.67	1.77	−.02	−.01	−.07	.07
6. CLE-T3	951	5.57	1.88	.02	−.02	.01	.02	.05	.03

Note. N, sample size; M, mean; SD, standard deviation; Int-T1/2/3, Intellect at measurement occasion T1, T2 and T3; SE-T2, self-efficacy at measurement occasion T2; CLE-T2/3, perception of the critical life events at T2 and T3.

*p < .05. **p < .01. ***p < .001.

Hypotheses were tested in two separate analyses for critical life events assessed at the measurement occasions T2 and T3, respectively. Results for T2 are depicted in Table 1. Age at T1 did not significantly predict levels in Intellect, even though there was a tendency for higher levels in Intellect for older compared to younger individuals. Time difference, i.e., the time elapsed since the first measurement occasion, significantly predicted levels in Intellect, indicating that levels in Intellect rise during adolescence and early adulthood, with an increase of 0.2 standard deviations per year.

For critical life events assessed at measurement occasion T2, we found no significant main effect on levels of Intellect, yet a significant interaction with time difference with a negative estimate of −.04. Contrary to our hypotheses, the increase in Intellect across time was stronger for individuals who experienced a critical life event related to graduating or moving as negative, compared to positive.

The fixed effect of self-efficacy on levels of Intellect was significant. Individuals scored one standard deviation above the mean on self-efficacy score, and, on average, 0.4 standard deviations above the mean on Intellect. Additionally, there was a significant interaction between self-efficacy and time difference on levels of Intellect. According to the positive estimate, individuals with high compared to low levels in self-efficacy showed a stronger increase in Intellect across time. No other effects reached significance.

Results for the valence of the critical life event assessed at T3 are depicted in Table 2. Main effects for age at T1, time difference, and self-efficacy were similar to the results reported above. The interaction between self-efficacy and time difference was no longer significant. Regarding the critical life event assessed at measurement occasion T3, the interaction with time difference was no longer significant. No other effects reached significance (Table 3).

Table 2.

Results for mixed model analyses with predicting development of intellect according to critical life events assessed at measurement occasion T2 and self-efficacy.

Fixed effect	Estimate	Std. error	df	t	p
(Intercept)	0.01	0.02	1020	0.42	0.67
age_T1	0.02	0.01	1023	1.79	0.07
time_diff	0.20	0.01	812	15.72	<0.001
self_eff	0.40	0.02	1016	17.40	<0.001
cle.x	0.00	0.02	1029	0.04	0.97
age_T1: time_diff	−0.01	0.01	796	−1.52	0.13
age_T1: self_eff	−0.01	0.01	1015	−0.85	0.40
time_diff: self_eff	0.04	0.01	794	3.19	0.00
age_T1: cle.x	0.00	0.01	1023	−0.20	0.84
time_diff: cle.x	−0.04	0.01	861	−2.93	0.00
self_eff: cle.x	0.02	0.02	1019	1.04	0.30
age_T1: time_diff:self_eff	0.00	0.01	712	−0.68	0.50
age_T1: time_diff:cle.x	0.01	0.01	787	0.75	0.46
age_T1: self_eff:cle.x	0.01	0.01	1012	1.03	0.30
time_diff: self_eff:cle.x	0.01	0.01	852	0.49	0.63
age_T1: time_diff:self_eff:cle.x	0.01	0.01	731	0.88	0.38

Note. age_T1: Age at measurement occasion T1; time_diff: elapsed time since the first measurement occasion at T1; self_eff: self-efficacy; cle.x: Valence of the critical life event obtained at measurement occasion T2.

Table 3.

Results for mixed model analyses with predicting development of intellect according to critical life events assessed at measurement occasion T3 and self-efficacy.

Fixed effect	Estimate	Std. error	df	t	p
(Intercept)	0.07	0.04	390.05	1.92	0.06
age_T1	0.02	0.02	388.13	0.72	0.47
time_diff	0.16	0.02	334.67	8.67	<0.001
self_eff	0.36	0.04	389.26	9.66	<0.001
cle.y	−0.01	0.04	392.06	−0.15	0.88
age_T1: time_diff	−0.01	0.01	322.69	−0.85	0.39
age_T1: self_eff	−0.01	0.02	387.90	−0.41	0.68
time_diff: self_eff	0.00	0.02	324.36	−0.18	0.85
age_T1: cle.y	0.00	0.02	393.48	0.14	0.89
time_diff: cle.y	0.00	0.02	325.96	−0.07	0.95
self_eff: cle.y	0.05	0.04	392.47	1.39	0.17
age_T1: time_diff:self_eff	0.00	0.01	299.85	0.32	0.75
age_T1: time_diff:cle.y	−0.01	0.01	352.56	−1.24	0.22
age_T1: self_eff:cle.y	0.01	0.02	393.72	0.45	0.66
time_diff: self_eff:cle.y	0.00	0.02	327.97	−0.24	0.81
age_T1: time_diff:self_eff:cle.y	0.00	0.01	340.02	−0.26	0.79

Note. age_T1: Age at measurement occasion T1; time_diff: elapsed time since the first measurement occasion at T1; self_eff: self-efficacy; cle.y: Valence of the critical life event obtained at measurement occasion T3.

Discussion

The present study aimed at investigating the development of trait Intellect in adolescence and emerging adulthood. Considering environmental influences, we examined the impact of critical life events on Intellect over a time period of three years. Moreover, we tested for a moderating effect of self-efficacy and, thus, asked whether the perceived confidence in one’s own effectiveness of action moderates an individual’s adaption and perception of life events and thus effects the development of trait Intellect.

In a large longitudinal sample, we found that mean levels of trait Intellect changed during adolescence and emerging adulthood. In line with results for the domain Openness/Intellect scores increased. Interestingly, age at measurement occasion T1, despite having considerable variance, was not significantly associated with Intellect, even though there was a tendency towards a positive relation. The pattern may be explained according to the concept of critical time periods. The first measurement occasion in our study contained data from an online career counseling test. Such a service is usually used to guide an upcoming career decision which was, according to the age of the participants, presumably their first vocational choice after finishing school. According to the German structured school system, pupils may finish secondary school after 9, 10, 12 or 13 years, which may explain the large variance in age at measurement occasion T1. However, the period during secondary school is characterized by stability, rather than change. This situation changes with the transition from school to vocational training, tertiary education, and working life – a situation that has been described as critical time period for personality development. During this relatively short time period of on average 2.8 years, Intellect increased significantly with 0.2 standard deviations per year. This might be because most prevalent cognitively demanding developmental tasks, such as detachment from the family and emotional independence, take place during this phase. Regarding Intellect, the need to be concerned about the future and to prepare for entering the job market constitutes an intellectual challenge that requires exploration and adaption. Previous findings show that most changes in Openness/Intellect over time occur when people are exposed to cognitively demanding tasks and exhibit creative thinking and exploratory behavior (Asselmann et al., 2021; Mussel et al., 2011; Mussel & Spengler, 2015; Schwaba et al., 2018). According to investment theory, it can be assumed that the investment in new social roles requires exploring and adapting as well as the manifestation of new behaviors and experiences which, over time, result in personality change (Roberts et al., 2005).

Regarding the perception of critical life events, the present results did not support our hypotheses. First, the valence of the critical life event assessed at both T2 and T3 was unrelated to average levels in Intellect. In the present study, participants could choose the event they rated on their own. For the analyses, we focused on life events that are presumably associated with characteristics of Intellect. As such, the events of graduating from school and moving out were chosen as they might be related to adaptability and flexibility and are thereby possibly more likely to affect Intellect levels. Thus, we did not influence or constrain their choice of event. Therefore, participants might also have selected events that are not relevant for the construct of Intellect. As these were discarded from the analyses, the power to find the expected effect reduced. Moreover, change in Intellect might not be affected by only a single critical event but might instead emerge through the sum of many environmental influences and cognitively demanding tasks that are representative for the expression of Intellect. Indeed, the number of experienced positive critical life experiences in the past was found to predict levels in the related investment traits need for cognition and openness to ideas (Strobel et al., 2017, 2018). Hence, assessing multiple major life events at once might be a fruitful way to study the development of Intellect.

Second, a significant effect of valence of the critical life event at T2 on changes in Intellect was in the opposite direction than expected. Participants experiencing a life event as more negative, compared to positive, showed a stronger increase in Intellect. Our hypothesis was based on the idea that positively experienced critical life events reflect a successfully mastered challenge that, in case of cognitively demanding tasks, required the application of thinking, learning, and problem-solving strategies. Thus, such situations might be evaluated more positively and sought out more likely in the future, which corresponds to the construct of Intellect. Apparently, results suggest otherwise. At this point, we might speculate that negative, rather than positive critical life events constitute a challenge that requires problem-solving and adapting. Mastering difficult situations due to persistence specifically coheres with the conquer-dimension of Intellect (Mussel, 2013), as also reflected in the construct of deprivation-type curiosity (Lievens et al., 2022; Litman, 2019). Additionally, an influence of negative events on long term positively evaluated outcomes has been investigated in the context of post-traumatic growth (e.g., Taku et al., 2021). While the latter refers to traumata and, as such, a more severe strain, the idea of crises as opportunities can be transferred to critical life events (Staudinger & Kessler, 2009). More research needs to be conducted to figure out how the valence of experienced life events affect personality development.

Regarding self-efficacy, our results suggest two interesting aspects. First, we found an effect of self-efficacy on changes in trait Intellect, and second, our results suggest that the initial level of self-efficacy is related to initial levels of Intellect. Both processes have one particular aspect in common: an individual’s assumption about the capability of the self. People high in Intellect like problem solving and learning new skills that help them master previously unknown challenges, whereas people high in self-efficacy are convinced of their ability to succeed at such challenges. Our results appear to indicate an inherent interrelationship from the start. Not only did we find that self-efficacy encourages the extension of characteristics that Intellect facilitates, but people high in Intellect are also more likely to show higher levels of self-efficacy. Especially in academic settings, a connection appears most prevalent. For example, previous research has suggested that Openness/Intellect and self-efficacy both serve as antecedents of study engagement, academic achievement, teaching success, and the maintenance of interest in the profession of teaching (Caprara et al., 2011; Colson et al., 2017). As an advantage of our study, we were able to demonstrate that a content overlap might be built more precisely on the notion of the facet level of Openness/Intellect. Presumably, individuals with high levels on Intellect and self-efficacy match themselves into environments that offer a good match, where they can pursue their interests and foster new skills. It is important to note that these effects emerged from exploratory analyses. In case that these effects are replicated in future confirmatory analyses, they may provide valuable insights into the underlying mechanisms of Intellect and encourage further research regarding self-efficacy. Additionally, it should be noted that the effect of self-efficacy on changes in Intellect failed to reach significance in the second analysis in which we investigated the critical life event at T3, rather than T2. As the variables for both Intellect and self-efficacy remained the same in these two analyses, this might be a matter of power. As a final limitation, self-efficacy was only assessed at T2. Thus, causal inferences cannot be drawn as third variables might have driven both, changes in Intellect and self-efficacy.

Self-efficacy did not function as a moderator of the perception of critical life events and change in Intellect during adolescence and emerging adulthood. We proposed an innovative approach that seemed promising in many ways. As stated earlier, encountering a critical life event can be a disturbing experience, which often requires the reorganization and reinterpretation of life in many contexts—indicators that trait Intellect facilitates. Therefore, further research should shed light on the conceptional mutual overlap of these constructs and expand the present findings by considering different life events, personality traits, and age groups. For example, research on mid-life personality development indicates how diverse individuals deal with prospective situations (e.g., transition into parenthood) in terms of believing in innate abilities and overcoming obstacles. For instance, especially Openness/Intellect and Extraversion have been shown to predict whether people will have children or not (van Scheppingen et al., 2016). Furthermore, concerning the perception of life events in mid-life, Sutin et al. (2010) found that people with high levels of Extraversion more often perceived a stressful life event as a “lesson learned,” whereas Neuroticism prospectively predicted that the event would be perceived as a “turning point.” Here, self-efficacy might not only determine the perception that one can successfully face a critical life event but might also contribute to selection effects and explain psychological growth in parenting. On the other hand, for individuals with low levels of self-efficacy a positive life event might be perceived as an unexpected, positive change, which might bolster confidence and impact personality development. Thus, effects working in opposite directions might explain the lack of a significant moderator effect in the present study.

Strengths, limitations, and future directions

One of the strengths of the current study is the large longitudinal sample we collected across three measurement occasions of adolescence and emerging adults from all over Germany. We used advanced statistical techniques, such as mixed linear models, to assess mean-level changes and moderating effects. However, there might be some self-selection effects in the sample because participants voluntarily chose to take part in a counseling test that was given to help students explore occupational opportunities after graduation. Thus, there might be preexisting differences because only adolescents and emerging adults who were concerned about their future might have taken the test in the first place. Moreover, change in Intellect should be differentiated between different cultural groups. Developmental transitions and environmental demands can be perceived very differently from individuals with distinct cultural backgrounds and more diverse samples are needed.

With regard to the assessment of critical life events, we considered the latest research in the field and followed a dimensional approach for examining the perception of critical life events (Luhmann et al., 2020). Nevertheless, the operationalization must be considered in the light of some limitations because we assessed life events at only two occasions (i.e., T2 and T3). Participants were able to indicate only whether they had experienced a critical life event during the last year. Therefore, we had no information about whether the event had occurred 2 weeks ago or 11 months ago, which may also have affected the person’s perception of the event.

Finally, caution should be taken when comparing our findings with other studies that have investigated the personality trait of Intellect. As stated earlier, the construct of Intellect is often defined and assessed in different ways. In the present study, our first measurement occasion only included an indicator of epistemic curiosity, which might not capture the full scope of the construct Intellect. While we included a second indicator on measurement occasions T2 and T3, the construct domain slightly changed.

Key insights

- Intellect increases in adolescence and emerging adulthood

- No evidence for influence of critical life events on Intellect

- Level and trajectories of Intellect are positively associated with self-efficacy

Relevance statement

It is an important path for personality research to explore the development of Intellect on a facet level and how critical life events are understood and integrated into life trajectories. The effect of core beliefs such as self-efficacy, appears to be a promising approach for gaining a deeper understanding of how Intellect evolves over time.

Supplemental Material

Supplemental Material - The development of intellect in adolescents and emerging adults: A longitudinal study of environmental influences and underlying processes

Supplemental Material for The development of intellect in adolescents and emerging adults: A longitudinal study of environmental influences and underlying processes by Jantje Hinrika de Vries and Patrick Mussel in Personality Science.

Footnotes

Author note

Not applicable.

Acknowledgements

Not applicable.

Author contributions

Jantje H. de Vries: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Resources, Software, Validation, Visualization, Writing - original draft, and Writing - review & editing.

Patrick Mussel: Conceptualization, Data curation, Formal analysis, Funding acquisition, Investigation, Methodology, Resources, Software, Supervision, Validation, Visualization, Writing - original draft, and Writing - review & editing.

Declaration of conflicting interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was funded by a research grant to Patrick Mussel by the Deutsche Forschungsgemeinschaft (Mu3045/6-1).

ORCID iD

Not applicable.

Data accessibility statement

Data sharing not applicable to this article as no datasets were generated or analyzed during the current study.

Supplemental material

Supplemental material for this article is available online. Depending on the article type, these usually include a Transparency Checklist, a Transparent Peer Review File, and optional materials from the authors.

Notes

References

Arnett

J. J.

(2000). Emerging adulthood: A theory of development from the late teens through the twenties. American Psychologist, 55(5), 469–480. https://doi.org/10.1037//0003-066X.55.5.469

Arnett

J. J.

(2007). Emerging adulthood: What is it, and what is it good for? Child Development Perspectives, 1(2), 68–73. https://doi.org/10.1111/j.1750-8606.2007.00016.x

Arnone

M. P.

Grabowski

B. L.

Rynd

C. P.

(1994). Curiosity as a personality variable influencing learning in a learner-controlled lesson with and without advisement. Educational Technology Research & Development, 42(1), 5–20. https://doi.org/10.1007/BF02298167

Asselmann

Klimstra

T. A.

Denissen

J. J. A.

(2021). Unraveling resilience: Personality predicts exposure and reaction to stressful life events. Personality Science, 2(1), 1–29. https://doi.org/10.5964/ps.6055

Bandura

(1997). Self-efficacy: The exercise of control. W. H. Freeman.

Bates

Mächler

Bolker

Walker

(2015). Fitting linear mixed-effects models using lme4. Journal of Statistical Software, 67(1), 1–48. https://doi.org/10.18637/jss.v067.i01

Benight

Bandura

(2004). Social cognitive theory of posttraumatic recovery: The role of perceived self-efficacy. Behaviour Research and Therapy, 42(10), 1129–1148. https://doi.org/10.1016/j.brat.2003.08.008

Bleidorn

Hopwood

C. J.

Lucas

R. E.

(2018). Life events and personality trait Change. Journal of Personality, 86(1), 83–96. https://doi.org/10.1111/jopy.12286

Bye

Pushkar

(2009). How need for cognition and perceived control are differentially linked to emotional outcomes in the transition to retirement. Motivation and Emotion, 33(3), 320–332. https://doi.org/10.1007/s11031-009-9135-3

10.

Cacioppo

J. T.

Petty

R. E.

Feinstein

J. A.

Jarvis

W. B. G.

(1996). Dispositional differences in cognitive motivation: The life and times of individuals varying in need for cognition. Psychological Bulletin, 119(2), 197–253. https://doi.org/10.1037/0033-2909.119.2.197

11.

Caprara

G. V.

Vecchione

Alessandri

Gerbino

Barbaranelli

(2011). The contribution of personality traits and self‐efficacy beliefs to academic achievement: A longitudinal study. British Journal of Educational Psychology, 81(Pt 1), 78–96. https://doi.org/10.1348/2044-8279.002004

12.

Caprara

G. V.

Zimbardo

P. G.

(2004). Personalizing politics: A congruency model of political preference. American Psychologist, 59(7), 581–594. https://doi.org/10.1037/0003-066X.59.7.581

13.

Cieslak

Benight

C. C.

Caden Lehman

(2008). Coping self-efficacy mediates the effects of negative cognitions on posttraumatic distress. Behaviour Research and Therapy, 46(7), 788–798. https://doi.org/10.1016/j.brat.2008.03.007

14.

Colson

Sparks

Berridge

Frimming

Willis

(2017). Pre-service teachers and self-efficacy: A study in contrast. Discourse and Communication for Sustainable Education, 8(2), 66–76. https://doi.org/10.1515/dcse-2017-0016

15.

Costa

P. T.

McCrae

R. R.

(1992). Revised NEO personality inventory (NEO-PI-R) and NEO five-factor inventory (NEO-FFI) professional inventory. Psychological Assessment Resources.

16.

Denissen

J. J. A.

Luhmann

Chung

J. M.

Bleidorn

(2018). Transactions between life events and personality traits across the adult lifespan. Journal of Personality and Social Psychology, 116(4), 612–633. https://doi.org/10.1037/pspp0000196

17.

de Vries

J. H.

(2020a). The development of intellect - the impact of life events and self-efficacy. Pre-registration. https://osf.io/6z9c5

18.

de Vries

J. H.

(2020b). The development of intellect - the impact of life events and self-efficacy. Repository for data and scripts. https://osf.io/pw9r2/?view_only=4dea01730ecc4a95a9c71ee12b4198e9

19.

De Vries

J. H.

Spengler

Frintrup

Mussel

(2021). Personality development in emerging adulthood - how the perception of life events and mindset affect personality trait change. Frontiers in Psychology, 12, 671421. https://doi.org/10.3389/fpsyg.2021.671421

20.

DeYoung

C. G.

(2014). Openness/Intellect: A dimension of personality reflecting cognitive exploration. In Cooper

M. L.

Larsen

R. J.

(Eds.), APA handbook of personality and social psychology: Personality processes and individual differences (Vol. 4, pp. 369–399). American Psychological Association. https://doi.org/10.1037/14343-017

21.

DeYoung

C. G.

Quilty

L. C.

Peterson

J. B.

(2007). Between facets and domains: 10 aspects of the Big Five. Journal of Personality and Social Psychology, 93(5), 880–896. https://doi.org/10.1037/0022-3514.93.5.880

22.

Dweck

C. S.

(2017). From needs to goals and representations: Foundations for a unified theory of motivation, personality, and development. Psychological Review, 124(6), 689–719. https://doi.org/10.1037/rev0000082

23.

Fleischhauer

Enge

Brocke

Ullrich

Strobel

(2010). Same or different? Clarifying the relationship of need for cognition to personality and intelligence. Personality and Social Psychology Bulletin, 36(1), 82–96. https://doi.org/10.1177/0146167209351886

24.

Geukes

van Zalk

Back

M. D.

(2017). Understanding personality development. International Journal of Behavioural Development, 42(1), 43–51. https://doi.org/10.1177/0165025416677847

25.

Goff

Ackerman

P. L.

(1992). Personality-intelligence relations: Assessment of typical intellectual engagement. Journal of Educational Psychology, 84(4), 537–552. https://doi.org/10.1037/0022-0663.84.4.537

26.

Goldberg

L. R.

(1992). The development of markers for the big-five factor structure. Psychological Assessment, 4(1), 26–42. https://doi.org/10.1037/1040-3590.4.1.26

27.

Jackson

J. J.

Thoemmes

Jonkmann

Ludtke

Trautwein

(2012). Military training and personality trait development: Does the military make the man, or does the man make the military? Psychological Science, 23(3), 270–277. https://doi.org/10.1177/0956797611423545

28.

Laks

D’Amico

Marano

Geraci

M. A.

Legge

(2013). Perceived self-efficacy and coping styles related to stressful critical life events. PLoS One, 8(7), Article e67571. https://doi.org/10.1371/journal.pone.0067571

29.

Lievens

Harrison

S. H.

Mussel

Litman

J. A.

(2022). Killing the cat? A review of curiosity at work. The Academy of Management Annals, 16(1), 179–216. https://doi.org/10.5465/annals.2020.0203

30.

Litman

(2019). Curiosity: Nature, dimensionality, and determinants. In Renninger

K. A.

Hidi

S. E.

(Eds.), The Cambridge handbook on motivation and learning (pp. 418–422). Cambridge University Press.

31.

Litman

J. A.

Mussel

(2013). Validity of the interest- and deprivation-type epistemic curiosity model in Germany. Journal of Individual Differences, 34(2), 59–68. https://doi.org/10.1027/1614-0001/a000100

32.

Lockenhoff

C. E.

Terracciano

Patriciu

N. S.

Eaton

W. W.

Costa Jr

P. T.

(2009). Self-reported extremely adverse life events and longitudinal changes in five-factor model personality traits in an urban sample. Journal of Traumatic Stress, 22(1), 53–59. https://doi.org/10.1002/jts.20385

33.

Lüdtke

Roberts

B. W.

Trautwein

Nagy

(2011). A random walk down university avenue: life paths, life events, and personality trait change at the transition to university life. Journal of Personality and Social Psychology, 101(3), 620–637. https://doi.org/10.1037/a0023743

34.

Luhmann

Fassbender

Alcock

Haehner

(2020). A dimensional taxonomy of perceived characteristics of major life events. Journal of Personality and Social Psychology, 121(3), 633–668. https://doi.org/10.1037/pspp0000291

35.

Luhmann

Hofmann

Eid

Lucas

R. E.

(2012). Subjective well-being and adaptation to life events: A meta-analysis. Journal of Personality and Social Psychology, 102(3), 592–615. https://doi.org/10.1037/a0025948

36.

Luszczynska

Benight

C. C.

Cieslak

(2009). Self-efficacy and health-related outcomes of collective trauma: A systematic review. European Psychologist, 14(1), 51–62. https://doi.org/10.1027/1016-9040.14.1.51

37.

Maciejewski

P. K.

Prigerson

H. G.

Mazure

C. M.

(2000). Self-efficacy as a mediator between stressful life events and depressive symptoms: Differences based on history of prior depression. The British Journal of Psychiatry: The Journal of Mental Science, 176(4), 373–378. https://doi.org/10.1192/bjp.176.4.373

38.

Mussel

(2010). Epistemic curiosity and related constructs: Lacking evidence of discriminant validity. Personality and Individual Differences, 49(5), 506–510. https://doi.org/10.1016/j.paid.2010.05.014

39.

Mussel

(2013). Intellect: A theoretical framework for personality traits related to intellectual achievements. Journal of Personality and Social Psychology, 104(5), 885–906. https://doi.org/10.1037/a0031918

40.

Mussel

(2021). The German personality panel (GePP). Freie Universität Berlin. https://doi.org/10.17605/OSF.IO/7W9YJ

41.

Mussel

(2023, May 15). A systematic review and natural language processing-based integration of the structure of core beliefs across fields. The Structure of Self-Related Core Beliefs. https://doi.org/10.31234/osf.io/ky4vu

42.

Mussel

Spengler

(2015). Investigating intellect from a trait activation perspective: Identification of situational moderators for the correlation with work-related criteria. Journal of Research in Personality, 55, 51–60. https://doi.org/10.1016/j.jrp.2015.01.002

43.

Mussel

Spengler

Litman

Schuler

(2012). Development and validation of the German work-related curiosity scale. European Journal of Psychological Assessment, 28(2), 109–117. https://doi.org/10.1027/1015-5759/a000098

44.

Mussel

Winter

Gelléri

Schuler

(2011). Explicating the openness to experience construct and its subdimensions and facets in a work setting. International Journal of Selection and Assessment, 19(2), 145–156. https://doi.org/10.1111/j.1468-2389.2011.00542.x

45.

Newsom

J. T.

(2017). Structural models for binary repeated measures: Linking modern longitudinal structural equation models to conventional categorical data analysis for matched pairs. Structural Equation Modeling: A Multidisciplinary Journal, 24(4), 626–635. https://doi.org/10.1080/10705511.2016.1276837

46.

Peterson

E. R.

Whiteman

M. C.

(2007). “I think I can, I think I can…”: The interrelationships among self-assessed intelligence, self-concept, self-efficacy and the personality trait intellect in university students in Scotland and New Zealand. Personality and Individual Differences, 43(4), 959–968. https://doi.org/10.1016/j.paid.2007.02.019

47.

Pusch

Mund

Hagemeyer

Finn

Wrzus

(2018). Personality development in emerging and young adulthood: A study of age differences. European Journal of Personality, 33(3), 245–263. https://doi.org/10.1002/per.2181

48.

R Core Team . (2018). R: A language and environment for statistical computing. R Foundation for Statistical Computing. https://www.R-project.org/

49.

Revelle

(2017). Psych: Procedures for psychological, psychometric, and personality research (version R package version 1.7.8). Northwestern University. Retrieved from. https://CRAN.R-project.org/package=psych

50.

Roberts

B. W.

Mroczek

(2008). Personality trait change in adulthood. Current Directions in Psychological Science, 17(1), 31–35. https://doi.org/10.1111/j.1467-8721.2008.00543.x

51.

Roberts

B. W.

Walton

K. E.

Viechtbauer

(2006). Patterns of mean-level change in personality traits across the life course: A meta-analysis of longitudinal studies. Psychological Bulletin, 132(1), 1–25. https://doi.org/10.1037/0033-2909.132.1.1

52.

Roberts

B. W.

Wood

Smith

J. L.

(2005). Evaluating Five Factor Theory and social investment perspectives on personality trait development. Journal of Research in Personality, 39(1), 166–184. https://doi.org/10.1016/j.jrp.2004.08.002

53.

Rosseel

(2012). lavaan: An R package for structural equation modeling. Journal of Statistical Software, 48(2), 1–36. https://doi.org/10.18637/jss.v048.i02

54.

Schwaba

Luhmann

Denissen

J. J. A.

Chung

J. M. H.

Bleidorn

(2018). Openness to experience and culture-openness transactions across the lifespan. Journal of Personality and Social Psychology, 115(1), 118–136. https://doi.org/10.1037/pspp0000150

55.

Schwarzer

Jerusalem

(1995). General Self-Efficacy Scale (GSE) [Database record]. APA PsycTests. https://doi.org/10.1037/t00393-000

56.

Simmons

J. P.

Nelson

L. D.

Simonsohn

(2012). A 21 word solution. University of Minnesota Twin Cities.

57.

Specht

Egloff

Schmukle

S. C.

(2011). Stability and change of personality across the life course: The impact of age and major life events on mean-level and rank-order stability of the big five. Journal of Personality and Social Psychology, 101(4), 862–882. https://doi.org/10.1037/a0024950

58.

Staudinger

U. M.

Kessler

E.-M.

(2009). Adjustment and growth: Two trajectories of positive personality development across adulthood. In Smith

M. C.

DeFrates-Densch

(Eds.), Handbook of research on adult learning and development (pp. 242–268). Routledge/Taylor & Francis Group.

59.

Strobel

Anacker

Strobel

(2017). Cognitive engagement mediates the relationship between positive life events and positive emotionality. Frontiers in Psychology, 8, 1861. https://doi.org/10.3389/fpsyg.2017.01861

60.

Strobel

Farkas

Hoyer

Melicherova

Köllner

Strobel

(2021). Cognitive motivation as a resource for affective adjustment and mental health. Frontiers in Psychology, 12, 581681. https://doi.org/10.3389/fpsyg.2021.581681

61.

Strobel

Enge

Fleischhauer

Reif

Lesch

K.-P.

Anacker

(2018). Intellectual investment, dopaminergic gene variation, and life events: A critical examination. Personality Neuroscience, 1, Article e3. https://doi.org/10.1017/pen.2018.2

62.

Sutin

A. R.

Costa

P. T.

Jr. Wethington

Eaton

(2010). Turning points and lessons learned: Stressful life events and personality trait development across middle adulthood. Psychology and Aging, 25(3), 524–533. https://doi.org/10.1037/a0018751

63.

Taku

Tedeschi

R. G.

Shakespeare-Finch

Krosch

David

Kehl

Grunwald

Romeo

Di Tella

Kamibeppu

Soejima

Hiraki

Volgin

Dhakal

Zięba

Ramos

Nunes

Leal

Gouveia

Calhoun L. G. (2021). Posttraumatic growth (PTG) and posttraumatic depreciation (PTD) across ten countries: Global validation of the PTG-PTD theoretical model. Personality and Individual Differences, 169, 110222. https://doi.org/10.1016/j.paid.2020.110222

64.

Van Scheppingen

M. A.

Jackson

J. J.

Specht

Hutteman

Denissen

J. J. A.

Bleidorn

(2016). Personality trait development during the transition to parenthood: A test of social investment theory. Social Psychological and Personality Science, 7(5), 452–462. https://doi.org/10.1177/1948550616630032

65.

Von Stumm

Chamorro-Premuzic

Ackerman

P. L.

(2011). Revisiting intelligence personality associations: Vindicating intellectual investment. In Chamorro-Premuzic

von Stumm

Furn- ham

(Eds.), Handbook of individual differences (pp. 217–241). Wiley-Blackwell.

66.

Von Stumm

Deary

I. J.

(2013). Intellect and cognitive performance in the lothian birth cohort 1936. Psychology and Aging, 28(3), 680–684. https://doi.org/10.1037/a0033924

67.

Zimmermann

Neyer

F. J.

(2013). Do we become a different person when hitting the road? Personality development of sojourners. Journal of Personality and Social Psychology, 105(3), 515–530. https://doi.org/10.1037/a0033019

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