Development of Multifaceted Risk Taking and the Relations to Sex Steroid Hormones: A Longitudinal Study

Risk taking is a multidimensional construct. It is currently unclear which aspects of risk‐taking change most during adolescence and if/how sex hormones contribute to risk‐taking tendencies. This study applied a longitudinal design with three time‐points, separated by 2 years, in participants aged 8–29 years (670 observations). The Balloon Analogue Risk Task, a delay discounting task, and various self‐report questionnaires were administered, to measure aspects of risk taking. Longitudinal analyses demonstrated mostly nonlinear age‐related patterns in risk‐taking behavior and approach‐related personality characteristics (peaking in late adolescence). Increased testosterone and estradiol were found to increase risk‐taking behavior and impulsive personality, but decrease avoidance‐like personality. This study demonstrates that risk taking is most pronounced in mid‐to‐late adolescence and suggests that sex hormones accelerate this maturational process.Article / Letter to editorInstituut PsychologieInstituut Pedagogische Wetenschappe

Sex effects on development of brain structure and executive functions: Greater variance than mean effects

Although male brains have consistently reported to be 8-10% larger than female brains, it remains not well understood whether there are differences between sexes (average or variance) in developmental trajectories. Furthermore, if sex differences in average brain growth or variance are observed, it is unknown whether these sex differences have behavioral relevance. The present longitudinal study aimed to unravel sex effects in cortical brain structure, development, and variance, in relation to the development of educationally relevant cognitive domains and executive functions (EFs). This was assessed with three experimental tasks including working memory, reading comprehension, and fluency. In addition, real-life aspects of EF were assessed with self- and parent-reported Behavior Rating Inventory of Executive Function scores. The full data set included 271 participants (54% female) aged between 8 and 29 years of which three waves were collected at 2-year intervals, resulting in 680 T1-weighted MRI scans and behavioral measures. Analyses of average trajectories confirmed general age-related patterns of brain development but did not support the hypothesis of sex differences in brain development trajectories, except for left banks STS where boys had a steeper decline in surface area than girls. Also, our brain age prediction model (including 270 brain measures) did not indicate delayed maturation in boys compared with girls. Interestingly, support was found for greater variance in male brains than female brains in both structure and development, consistent with prior cross-sectional studies. Behaviorally, boys performed on average better on a working memory task with a spatial aspect and girls performed better on a reading comprehension task, but there was no relation between brain development and cognitive performance, neither for average brain measures, brain age, or variance measures. Taken together, we confirmed the hypothesis of greater males within-group variance in brain structures compared with females, but these were not related to EF. The sex differences observed in EF were not related to brain development, possibly suggesting that these are related to experiences and strategies rather than biological development.Pathways through Adolescenc

Contextualizing adolescent structural brain development: environmental determinants and mental health outcomes

Pathways through Adolescenc

Unraveling age, puberty and testosterone effects on subcortical brain development across adolescence

The onset of adolescence in humans is marked by hormonal changes that give rise to secondary sexual characteristics, noted as puberty. It has, however, proven challenging to unravel to what extent pubertal changes may have organizing effects on the brain beyond chronological age, as reported in animal studies. The present longitudinal study aimed to characterize the unique effects of age and puberty on subcortical brain volumes and included three waves of data collection at two-year intervals and 680 T1-weighted MRI scans of 271 participants (54% females) aged between 8 and 29 years old. Generalized additive mixed model procedures were used to assess the effects of age, self-report pubertal status and testosterone level on basal ganglia, thalamus, hippocampus, amygdala and cerebellum gray matter volumes. We observed age-related increases in putamen and pallidum volumes, and decreases in accumbens and thalamus volumes, all show larger volumes in boys than girls. Only the cerebellum showed an interaction effect of age by sex, such that males showed prolonged increases in cerebellar volume than females. Next, we showed that changes in self-report puberty status better described developmental change than chronological age for most structures in males, and for caudate, pallidum and hippocampal volumes in females. Furthermore, changes in testosterone level were related to development of pallidum, accumbens, hippocampus and amygdala volumes in males and caudate and hippocampal volumes in females. The modeling approach of the present study allowed us to characterize the complex interactions between chronological age and pubertal maturational changes, and the findings indicate puberty unique changes in brain structure that are sex specific.Pathways through Adolescenc

Inter-individual variability in structural brain development from late childhood to young adulthood

A fundamental task in neuroscience is to characterize the brain's developmental course. While replicable group-level models of structural brain development from childhood to adulthood have recently been identified, we have yet to quantify and understand individual differences in structural brain development. The present study examined inter-individual variability and sex differences in changes in brain structure, as assessed by anatomical MRI, across ages 8.0-26.0 years in 269 participants (149 females) with three time points of data (807 scans), drawn from three longitudinal datasets collected in the Netherlands, Norway, and USA. We further investigated the relationship between overall brain size and developmental changes, as well as how females and males differed in change variability across development. There was considerable inter-individual variability in the magnitude of changes observed for all examined brain measures. The majority of individuals demonstrated decreases in total gray matter volume, cortex volume, mean cortical thickness, and white matter surface area in mid-adolescence, with more variability present during the transition into adolescence and the transition into early adulthood. While most individuals demonstrated increases in white matter volume in early adolescence, this shifted to a majority demonstrating stability starting in mid-to-late adolescence. We observed sex differences in these patterns, and also an association between the size of an individual's brain structure and the overall rate of change for the structure. The present study provides new insight as to the amount of individual variance in changes in structural morphometrics from late childhood to early adulthood in order to obtain a more nuanced picture of brain development. The observed individual-and sex-differences in brain changes also highlight the importance of further studying individual variation in developmental patterns in healthy, at-risk, and clinical populations.Pathways through Adolescenc

Understanding the dynamics of the developing adolescent brain through team science

One of the major goals for research on adolescent development is to identify the optimal conditions for adolescents to grow up in a complex social world and to understand individual differences in these trajectories. Based on influential theoretical and empirical work in this field, achieving this goal requires a detailed understanding of the social context in which neural and behavioral development takes place, along with longitudinal measurements at multiple levels (e.g., genetic, hormonal, neural, behavioral). In this perspectives paper, we highlight the promising role of team science in achieving this goal. To illustrate our point, we describe meso (peer relations) and micro (social learning) approaches to understand social development in adolescence as crucial aspects of adolescent mental health. Finally, we provide an overview of how our team has extended our collaborations beyond scientific partners to multiple societal partners for the purpose of informing and including policy makers, education and health professionals, as well as adolescents themselves when conducting and communicating research.Social decision makingStress and PsychopathologyFSW - Self-regulation models for health behavior and psychopathology - oudPathways through Adolescenc

Challenging emotional memory

Emotional experiences tend to be very well remembered. The ability to recall the important events in life is crucial to adaptively respond to future situations. The strength of emotional memories may, however, also become harmful and maladaptive when it constraints daily functioning, such as in patients suffering from post-traumatic stress disorder. From an evolutionary perspective, stability of our memory system is essential to recognize important predictors (i.e., stimulus or context) of imminent threat and reward. However, since it is unlikely that a stimulus or context will keep its predictive value forever, memories need to be malleable as well. Recently it has been shown that upon recall, memories can enter a labile state where they are sensitive to change before being restabilized again. This process is referred to as reconsolidation. In the current thesis, we aimed to gain more insight into the malleable nature of emotional memory. In five empirical chapters we experimentally challenged emotional memory using different experimental paradigms and pharmacological and behavioral manipulations to alter the strength of emotional memory. We showed that 1) there are certain boundary conditions under which reconsolidation does not occur and emotional memory cannot be weakened 2) stress exposure after memory reactivation can strengthen memory and enhance the contextual embedding of emotional memory. These findings indicate that the process of reconsolidation plays a key role in keeping our memories up to date

The roles of shame and guilt in the development of aggression in adolescents with and without hearing loss

This longitudinal study examined how shame and guilt contribute to the development of reactive and proactive aggression in adolescents with and without hearing loss. Adolescents between 9 and 16 years old (adolescents with hearing loss (n = 80; Mage = 11.91) and without hearing loss (n = 227; Mage = 11.63)) completed self-reports on three occasions with an interval of 9 months. Mixed model analyses revealed that both reactive aggression and proactive aggression decreased with age, whereas shame and guilt peaked in early adolescence. Adolescents with hearing loss reported higher levels of proactive aggression, lower levels of shame and guilt, and showed protracted development for guilt compared to their hearing peers. In both groups, shame contributed to an increase in reactive aggression, whereas guilt contributed to a decrease in proactive aggression. These longitudinal associations highlight the unique role that shame and guilt play in the development of adolescent aggression.Pathways through Adolescenc