What Are The Behavioral Changes During Adolescence

Abstruse

Adolescence is a time of dramatic changes including rapid physical growth, the onset of sexual maturation, the activation of new drives and motivations, and a wide array of social and melancholia changes and challenges. This review focuses on behavioral changes in this interval and is organized past the merits that a key prepare of these adolescent changes are part of a more general re-orientation of social behavior. More specifically we hypothesize that pubertal maturation is associated with the activation of social and motivational tendencies, which in turn influence behavior and emotion in adolescence depending upon interactions with social context. We focus on evidence for two examples of these motivational changes: 1) increases in awareness seeking (motivational tendency to desire to feel high-intensity, heady experiences) and 2) stronger natural interest in—and pursuit of—contact with peers and potential romantic partners. We consider how these motivational changes contribute to the broader social re-orientation of boyhood, including exploration of social experiences, the evolution of skills and knowledge relevant to taking on adult social roles, individuation from family, and the institution of an individual identity, all of which represent cadre developmental tasks during this menses in the life span (Blakemore, 2008; Dahl & Spear, 2004; Steinberg & Morris, 2000). The paper besides emphasizes the importance of investigating and understanding the direct influences of puberty on behavior and disentangling these from the broader set up of changes during adolescent evolution.

The onset of adolescence is a time of dramatic biological, behavioral, and social changes. These include rapid physical growth, sexual maturation, and emotional changes that range from igniting romantic interests to increased self-consciousness and social anxieties. Boyhood is also a time of new social challenges such as increasing academic pressures, competition with peers, and difficulties learning to rest desires for immediate gratification with an understanding of the importance of long-term goals and consequences (Dahl & Spear, 2004). Amidst this myriad of adolescent changes in that location are too sharply increasing rates of bug with the command of behavior and emotion despite the fact that the regulatory capacities are improving across this interval of development. As discussed elsewhere in this issue, adolescence involves ongoing evolution of encephalon structure (Lenroot & Giedd, in printing; Paus, in press), sleep (Feinberg & Campbell, in press), and brain function (Somerville, Jones, & Casey, in printing), including gradual increases in capacities for cognitive command and executive part (Luna, Padmanabhan, & O'Hearn, in press).

In the electric current newspaper, we examine pubertal maturation in relation to several aspects of boyish behavior, with an emphasis on the increase in reproductive hormones that are instrumental to pubertal evolution. We review emerging evidence that pubertal maturation is closely associated with a set of affective (emotional and motivational) changes, which in turn influence some behavioral tendencies. We put along the hypothesis that many (if not about) of the behavioral changes associated with pubertal maturation are linked to activational effects on specific motivational tendencies—including increased awareness seeking, and stronger natural attraction to peer and romantic contexts—and that the subsequent influences on individual behavior are highly variable depending upon the social context as well as underlying individual differences in temperament/personality.

Understanding these puberty-specific changes in behavior represents an of import dimension of normal development in boyhood; it as well has broad clinical and social policy relevance. Interactions between these motivational tendencies and the social contexts that amplify these tendencies are relevant to understanding the wellness paradox of boyhood. That is, adolescence represents one of the healthiest periods of the life span with respect to concrete health, yet overall morbidity and mortality rates increase 200% (Centers for Disease Control and Prevention, 2009; Ozer, Macdonald, & Irwin, 2002; Resnick, et al., 1997). Rates of accidents, suicide, homicide, depression, alcohol and substance corruption, HIV, Hepatitis C, unwanted pregnancies, anorexia and bulimia ascent sharply in this developmental period (Force, 1996; Ozer, et al., 2002). On the one hand, these various types of boyish health bug appear heterogeneous; on the other hand, the majority of these health consequences reflect difficulties with control of emotion and behavior.

An of import framework for understanding some of these affective changes at puberty can be understood inside the broader social re-orientation of adolescence. As noted by recent reviews on the social neuroscience of adolescence (east.g. Blakemore, 2008; Nelson, Leibenluft, McClure, & Pine, 2005) adolescence is marked past changes in social cognition and by functional and structural development of brain networks implicated in social processing. We hypothesize that the pubertal rise in reproductive hormones activates motivational tendencies—including appetitive motivations in the realm of social goals and rewards—that assistance to facilitate this social re-orientation. These are evident in adolescents' increasing motivations to attract friends and romantic partners, to reach social status, and more more often than not, in their natural tendencies to pay more than attending to, care about, and react to peer, romantic, and sexual contexts.

The activation of these motivational tendencies tin have positive effects on behavior – specifically, natural inclinations leading to learning and exploration of social environments in means that contribute to acquiring relevant knowledge and skills. Yet, stronger attraction to peer and romantic pursuits--specially in combination with increased sensation seeking--can contribute to a wide range of risky adolescent behaviors associated with negative health consequences, especially in some social contexts.

Earlier returning to these clinical and social policy implications in more detail, nosotros will first review the evidence for puberty-specific changes in behavior. To begin, nosotros volition briefly describe the hormonal and physical changes of puberty and outline the limitations and challenges to enquiry on puberty and behavior, and then describe emerging areas of progress in disentangling puberty-specific neurobehavioral changes. Next, we focus on two areas of investigation where there is potent evidence for puberty-specific behavioral changes--sensation-seeking and motivation for social status--and then consider these in relation to our model emphasizing motivational tendencies.

Pubertal Development

Adolescence tin be defined as that bad-mannered menstruum betwixt the onset of sexual maturation and the attainment of adult roles and responsibilities (Dahl & Spear, 2004). The transition into adolescence is marked by pubertal development, which includes activation of the hypothalamic-pituitary-gonadal (HPG) axis and the hypothalamic-pituitary-adrenal (HPA) axis (run across Buck Louis, et al., 2008 for a detailed overview of pubertal development). Puberty is triggered by increases in the frequency and amplitude of nocturnal pulses of gonadotropin-releasing hormone (GnRH) in the hypothalamus. There is little research on the age at which GnRH pulses begin in humans, only studies of nonhuman primates suggest that there are private differences in the function of the GnRH system and in the response to factors that influence GnRH function (Centeno et al., 2007). Given this, and given sexual practice differences in puberty onset in humans, information technology is difficult to guess the historic period at which increased GnRH pulsing begins in humans. A critical frequency of GnRH pulses activates pituitary release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) pulses, which in turn, activate the gonads. In girls, this leads to ovarian secretion of estradiol, progesterone, and ovarian androgens, and eventually to the evolution of ovulatory menstrual cycles. In boys, LH pulses lead to testicular secretion of androgens. In add-on to gonadal development, puberty likewise involves of import changes such as increases in adrenal androgens, rapid growth in body size, changes in distribution of body fat, and development of secondary sex characteristics.

Importantly, puberty represents a re-activation of specific neuroendocrine systems. That is, the reproductive hormones that increment sharply at puberty stand for a second re-activation of neuroendocrine axes that were also active in infancy [see figure one for an illustration of this pattern for males]. This 2-phase blueprint of the effects of reproductive hormones in evolution has been described in relation to the organizational-activational hypothesis (Phoenix, Goy, & Young, 1967; see Romeo, 2003 for a more contempo review). This model focuses on the observation that the same hormones that initially organize sex differences in the torso and the encephalon during fetal and early on postnatal life are besides the hormones that exert activational effects on behavior during puberty.

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Illustration of an organizational-activational model for boys, showing early activation of GnRH pulsing, a menstruation of quiescence, then re-activation of the GnRH pulsing at the onset of puberty.

More than recently, show from animal research on hormonal influences on behavior indicates that sex-steroid hormones can likewise accept activational effects on brain development at puberty (Schulz, Molenda-Figueira, & Sisk, 2009). That is, puberty can be viewed as a period of re-activation of hormonal influences on behavior and the brain. Brain evolution is highly sensitive to hormone influence perinatally, but the activational furnishings of hormones do not just occur during perinatal evolution, as once idea. Examples of puberty-related organization of behavior are evident in both males and females, equally illustrated past the Syrian hamster model of pubertal hormone influence. In male hamsters, the organizing influence of pubertal hormones has been studied by castration after perinatal hormone influence simply before puberty. Every bit a issue, testosterone at puberty appears to influence increases in male hamsters' sexual beliefs and ambitious behavior (Schulz & Sisk, 2006), and their reduction in anxiety-related locomotor activity in a novel surroundings (Primus & Kellogg, 1989). In female person hamsters, which have been less extensively studied, ovarian hormones at puberty influence food-guarding and feeding behaviors (Field, Whishaw, Forgie, & Pellis, 2004; Swithers, McCurley, Hamilton, & Doerflinger, 2008). At a neural level, organizational effects of pubertal hormones include cellular-level changes in brain circuits, such equally testosterone influences on increases in white matter volume (Perrin, et al., 2008). Importantly, pubertal hormones influence behavior directly but likewise influence experience, which in turn influences behavior (Schulz, et al., 2009). Thus, there are several paths from hormones to behavior in boyhood.

In humans, variability in the onset and progression of puberty exists, and at that place is bear witness that environmental influences contribute to this variability. Specifically, endocrine-disrupting chemicals, diet, and body size seem to play a role in this variability, but more inquiry is needed to empathise the nature of these factors (Buck Louis, et al., 2008). There also appear to be some cultural differences in secular trends toward earlier onset of puberty in the United States, with more prove for decrease in the age of pubertal onset in Mexican-American and African-American youth than in European-American youth (Himes, 2006). Nevertheless, there is stronger show for a secular trend in girls than in boys, and in girls, this tendency appears to be present for chest evolution and menarche rather than for other signs of puberty (Euling, et al., 2008). It is not known exactly what triggers the onset of puberty, although genetic factors and feel announced to contribute. Emerging genetic evidence now suggests that the kisspeptin-GPR54 regulatory system plays a role in puberty onset through influence on GnRH release (Buck Louis, et al., 2008; Plant, 2006).

Measurement of puberty in humans is typically conducted through nomenclature of concrete development into stages originally defined by Tanner (Marshall & Tanner, 1968). This system includes 5 stages on two scales: one for breast development in girls and gonadal development in boys; and 1 for pubic hair development in boys and girls. Classification with this arrangement can be conducted either through concrete exam and rating past a trained medical or research professional or through self-report based on descriptions of visual depictions of the stages. There are important concerns about the reliability and validity of pubertal staging given the atheoretical basis for the arroyo and the somewhat arbitrary nature of the five-point scale itself. Other means of assessing puberty include menarche in girls, level of circulating reproductive hormones (due east.g., luteinizing hormone), bone age conclusion, and measurement of uterine and ovarian book (Buck Louis, et al., 2008). Each method has advantages and disadvantages (for a broad discussion of both conceptual and methodological problems regarding measures of puberty run across Dorn, Dahl, Woodward, & Biro, 2006; Shirtcliff, Dahl, & Pollak, 2009).

In humans, the strongest show for puberty-specific influences on beliefs to date is in the domain of romantic interest and sexual motivation (Richards, Crowe, Larson, & Swarr, 1998; Udry, 1987). There is also bear witness that some changes in emotional intensity are more closely linked to pubertal maturation rather than historic period, including measures of parent-adolescent disharmonize (Steinberg, 1988, 1989; Steinberg & Morris, 2000). In addition, there is strong evidence that at to the lowest degree some aspects of sensation-seeking increase at puberty (Steinberg, 2004). These changes, along with the general increase in salience and pursuit of social goals will be considered within the larger framework of social re-orientation that is key to adolescence.

Challenges in Enquiry on Puberty and Beliefs

Information technology is essential to point out that we are currently limited in our understanding of puberty-specific changes in behavior at least in function because few studies have been designed in ways to specifically address the impact of pubertal maturation on behavioral development and the relevant developing neural systems. Some of import aspects of cerebral development change with age, not puberty (Velanova, Wheeler, & Luna, 2008), and describing the difference has important implications for understanding which developmental changes are linked to puberty and which are linked to other aspects of adolescent development (e.grand., social experiences).

Outset of all, it is important to note that a large number of the about influential studies of adolescent cognitive, emotional, and brain development accept contained no measures of puberty at all (eastward.g. Giedd, et al., 1999; Gogtay, et al., 2004; encounter Keating, 2004 for review). For example, studies have compared a group of participants with an age range in the teenage years with a grouping of adults or a group of younger children, but have not examined pubertal development in terms of either sexual maturation or circulating hormone levels to determine pubertal status of their adolescent participants. Because adolescence is defined past both pubertal maturation and social changes it is therefore difficult to uncrease the effects of social context on boyhood from the furnishings of puberty. Secondly, even among the studies that have obtained objective measures of puberty, these are often based on questionnaire or self-rating of maturation, and information technology is oft difficult to uncrease age furnishings from pubertal maturation in samples with a broad age range, because in most such samples, age and puberty are closely correlated with each other (and age is measured with greater precision than categories of pubertal phase) (Shirtcliff, et al., 2009).

However, in that location have been a few studies that take utilized cross-sequential or longitudinal designs with measures of reproductive hormones, such as the Cracking Smoky Mount Study (Costello, et al., 1996) from which several puberty-specific findings have emerged, including strong evidence for a direct link between puberty and risk for affective disorders (Angold, 2003; Angold, Costello, Erkanli, & Worthman, 1999; Angold, Erkanli, Silberg, Eaves, & Costello, 2002; Angold, Worthman, & Costello, 2003). Another case of a written report design that allows disentanglement of puberty-specific effects is illustrated past Martin et al. (2002). They selected 208 children in a narrow age range (11-xiv years of age) and examined the influence of pubertal maturation on sensation-seeking as well as nicotine, booze, and marijuana use and establish that cocky-reported puberty, just not historic period, was correlated with increased sensation-seeking.

Contempo progress in this area of enquiry is promising, with more than efforts to examine the role of puberty in adolescent behavior and experience more explicitly. Developmentalists are at present considering the role of pubertal maturation in the psychophysiology of melancholia reactivity (Quevedo, Benning, Gunnar, & Dahl, 2009; Silk, et al., 2009) and stress responding (due east.g. Stroud, et al., 2009).

Most recently, a study we are conducting at the University of Pittsburgh is examining pubertal development, genetic factors, reward-related and threat-related brain role, inhibitory command, activeness monitoring, and touch on regulation in 125 adolescents in the narrow age range of xi-thirteen years. By selecting a express age range and recruiting girls to be somewhat younger than boys, and then re-studying the sample in a longitudinal blueprint, nosotros volition be able to examine pubertal influences on brain function and behavior without the usual misreckoning by historic period effects. To date, nosotros have institute that pubertal maturation—contained of the furnishings of age—influences both brain construction and encephalon office relevant to social reorientation. Specifically, sexual maturation, measured by Tanner stage of physical evolution is associated with increased medial temporal lobe volume in boys, and circulating testosterone level measured past bloodspot sampling and hormone assay is associated with decreased total grayness affair book in girls (Bramen, Dahl, Forbes, & Sowell, under review). Sexual maturation and testosterone are associated with reduced striatal reactivity and increased medial prefrontal reactivity in response to winning in a monetary reward functional magnetic resonance imaging image (Forbes, Phillips, et al., under review). Sexual maturation is associated with decreased amygdala and ventrolateral prefrontal reactivity to cryptic social threats—that is, fearful and neutral facial expressions—only no change in reactivity to unambiguous social threats—that is, angry facial expressions (Forbes, Hariri, Phillips, Ryan, & Dahl, under review). Together, these findings indicate that puberty influences the development of brain systems that play a role in processing affective and social stimuli. As noted in animal studies of re-arrangement of the encephalon by pubertal hormones, hormones can exert influences on neural circuits at cellular levels (Schulz, et al., 2009).

Adolescent Beliefs Influenced past Puberty

Several perspectives point that puberty has an of import influence on boyish—and eventually developed—behavior. Models of hormones and behavior suggest that puberty has an organizational outcome on brain development and boyish behavior, creating a foundation for long-term patterns of behavior, including problem behaviors such as psychopathology (Sisk & Zehr, 2005). Inquiry on brain structure in adolescents with atypical patterns of reproductive hormones (e.g., congenital adrenal hyperplasia) or genetic disorders involving sex chromosomes provides additional evidence for the role of hormones in brain development (Giedd, et al., 2006).

Although changes in hormone levels represent an obvious and strongly influential component of puberty, associations between puberty and beliefs cannot exist assumed to reflect straight effects of hormones on behavior. Based on animal and basic studies, it is clear that the timing and patterning of hormone release (due east.g., pulses of hormones at a key frequency, or rates of rising of hormone level) can represent the biological signal (encounter Knobil, 2005 for a classic instance of research on hormonal pulse signals). There also is evidence that hormones can have different influences on behavior during puberty than in adulthood and depending on the behavioral context. An instance of this is support for the claiming model of testosterone-aggression associations (Archer, 2006), which predicts that while circulating testosterone levels increment to developed levels during puberty, testosterone does not produce a direct increment in aggression during boyhood. In adulthood, the testosterone-assailment association is different. In adults, testosterone increases with circumstances such as competition among males for mates, and aggression also increases. Evidence from human and not-human primate studies indicates that testosterone does not necessarily accept a direct relation to aggressive behavior. Rather, testosterone increases motivation to accomplish higher status, and the effect of testosterone level on behavior is dependent on social and developmental context (Wallen, 2001).

Sensation-Seeking

One key area of inquiry relevant to these issues in man adolescent development is the well documented alter in sensation-seeking that occurs during adolescence. Prior to reviewing the data in this area, it is important to emphasize that the term sensation-seeking has been used broadly to include a range of impulsive and reckless behaviors, nevertheless the central component of awareness-seeking can be understood as a motivational tendency: wanting/liking high-sensation high-arousal experiences. Thus, the increase in sensation-seeking that appears to occur at the onset of adolescence (and may exist linked directly to the rise in reproductive hormones) is an instance of the type of motivational tendency described in our model.

Sensation-seeking, or the pursuit of loftier-intensity, exciting experiences, occurs more than often in adolescents than in either children or adults. Notably, sensation-seeking tendencies are correlated more strongly with puberty than age (Spear, 2000; Steinberg, 1999). According to Arnett (1992, 1994; Arnett & Balle-Jensen, 1993), sensation-seeking is i of the developmental contributors to risk behaviors and is more likely to emerge during adolescence than any other fourth dimension period. In a study of 1,053 Danish youth (12-twenty years of age), sensation-seeking was plant to be related to nigh types of risk behaviors (e.yard. sex activity without contraception, marijuana apply, cigarette smoking) (Arnett & Balle-Jensen, 1993). Thus, the positive thrill associated with risk-taking sometimes has a greater influence on behavioral choices than the cognitive understanding of possible negative consequences associated with a item behavior. In similar ways, peer pressure level, concerns nearly social rejection, and the want to exist popular tin can sharply bear upon adolescents' behavior.

1 of the kickoff studies to demonstrate the specific link betwixt sensation-seeking and puberty was conducted past Martin et al. (2002) in a design that focused on adolescents inside a narrow age range of xi-fourteen years. In this report, sensation-seeking was correlated not with age merely with pubertal maturation. Boys and girls with more than advanced pubertal evolution had higher ratings of sensation seeking and greater drug use (Martin, et al., 2002).

A contempo study by Steinberg and colleagues (2008) has further elucidated changes in sensation seeking during adolescent development. In add-on, the study aimed at disentangling sensation-seeking (as an appetitive motivation for exciting experiences), and impulsivity, which is sometimes associated with awareness seeking, simply reflects quick deportment that occur without consideration of consequences. Using behavioral (e.g., Iowa Gambling Task, delay discounting) and cocky-study measures (Zuckerman, 1971) in a large sample of adolescents, the authors reported that sensation-seeking and impulsivity follow different developmental patterns. Awareness-seeking increases from historic period x, peaks betwixt 13-16 years, and then declines. Impulsivity, on the other hand, steadily declines from age ten to age xxx. The authors interpret their findings as pointing to explanations of the increased risk-taking that occurs during early adolescence, when both sensation-seeking and impulsivity are high.

Motivational Tendencies: Studies of Social Dominance and Sexual Behavior

While social behavior changes importantly with pubertal maturation, enquiry on social authority suggests that changes cannot but exist attributed to hormones whose levels modify at puberty. Social context—including limerick of the social group, rank within the group, and social feel—also changes meaningfully during adolescence and can collaborate with hormones to exert its ain influence on social behavior. To illustrate this, we describe some compelling studies of sexual behavior in non-human primates by Wallen and colleagues. These studies illustrate the relation of reproductive hormones to social dominance and sexual behavior.

Extended to humans, these not-human being primate studies underscore the critical importance of motivational tendencies for social authorisation rather than any uncomplicated consequence on behavior. Because there are similarities in pubertal evolution in humans and non-human primates—including the pattern of GnRH release across development and the hormones involved in the HPG axis—non-human primates, particularly rhesus monkeys, are considered a valuable animal model for puberty in humans (Plant, 2001, 2008). For example, humans and non-homo primates both showroom a clear menstruum of quiescence betwixt perinatal HPG action and pubertal HPG activity. Clearly, more research is needed that is designed to disentangle this complex set of changing behaviors of boyhood and to more rigorously test the hypothesis that motivation to accomplish social authorisation in humans increases with increasing levels of reproductive hormones during puberty. In addition, studies to examine the separate and overlapping contributions of hormones, social environs, and social customs to these behaviors in humans are likewise needed.

A valuable contribution of the not-human primate literature on testosterone and social beliefs to understanding the part of hormones in social behavior is its accent on the influence of both reproductive hormones and social context. These two factors can interact to influence behavior. For example, sexual behavior in female person rhesus monkeys is influenced both by social context (e.one thousand., pair vs. multi-animate being grouping) and past ovarian cycle phase, with some behaviors more frequent in particular social contexts at certain cycle phases (Wallen & Winston, 1984). Similarly, social rank in females influences historic period at showtime ovulation (Zehr, Van Meter, & Wallen, 2005), with higher-rank females more likely to ovulate at an early age. This finding underscores the influence of social context on pubertal evolution. Thus, when considering the role of puberty in social potency behavior in humans, it is critical to consider more than just hormone influences. A more than comprehensive arroyo to examining puberty and behavior, then, will besides accept into account social experiences, settings, and developmental history.

For instance, there is an interaction between testosterone level and sexual feel in predicting female-mounting behavior in male person rhesus monkeys (Wallen, 2001). During puberty, there is an increase in the tendency for male monkeys to demonstrate mounting beliefs toward females. This change in social behavior occurs during a menstruum in which testosterone levels are increasing. Wallen and colleagues observed the mounting behavior of male rhesus monkeys living in large, multi-male person and multi-female social groups. These males were observed for approximately 100 hours at age 1.5 years, which is during the juvenile phase and before puberty, and then again for approximately 55 hours during the mating season at 3.five years, at which puberty is beginning. Claret samples were collected weekly and assayed for testosterone. Notably, they plant that testosterone levels were not direct related to development of mounting behaviors during puberty. Instead, sexual experience, divers as the ejaculatory reflex, was associated with behavior independent of testosterone level. Even low-testosterone male monkeys exhibited high proportions of female-mounting behaviors if they had had a successful sexual experience. Wallen and colleagues translate their data as indicating that testosterone levels are important in motivating the appetite for social behavior at a level sufficient for naïve males to overcome hesitation to approach mature females. However once an beast has had the rewarding feel of a successful sexual encounter, motivation from other sources (e.yard., reward-learning) is sufficient, and hormone levels are no longer associated with this behavior. Similarly, when androgen levels in adult male monkeys are reduced through a unmarried-dose pharmacologic manipulation, changes in sexual behavior depend upon social context. In these "testicular suppression" studies, male person rhesus monkeys were given a unmarried dose of antide, a gonadotropin-releasing hormone antagonist that reduces androgen levels to castration levels. Subsequently testicular suppression, male sexual behavior decreased more than rapidly when males were placed in multiple-male social groups, in which competition for mates is present, than when they were placed in single-male social groups, where there is no contest (Davis-daSilva & Wallen, 1989). Male sexual behavior also decreased more slowly in group contexts than in male-female pair contexts (Wallen, 1999; Wallen, Eisler, Tannenbaum, Nagell, & Mann, 1991). In add-on, in multiple-male social groups, social rank and sexual experience influence changes in sexual behavior later testicular suppression. Notably, sexual behavior decreased more quickly after testicular suppression in low-ranking male monkeys and inexperienced male monkeys than in loftier-ranking or sexually experienced monkeys (Wallen, 1999).Together, these findings point that both during puberty and during machismo, social context and social feel play an of import office in regulating the influence of hormones on behavior. While reproductive hormones are critical to social behaviors, the behaviors they influence are sensitive to social context.

Conclusions

In sum, the current review of pubertal influences on behavior indicates that many dramatic changes occur in behaviors related to increasing social ambition and social re-orientation at adolescence. Sensation-seeking and motivation for social authorisation are examples of behaviors subject to pubertal influence.

Although these examples provide a compelling view of the role of puberty in adolescent social development and subsequently adult beliefs, research on the influence of puberty on adolescent social development requires further elaboration. Findings must be replicated, and the multiple sources of influence on puberty itself and on the behaviors it influences remain to be sorted out. The combination of early organizing effects of hormones and early on social experiences can prepare the stage for pubertal evolution and associated behavior changes, and the feel of pubertal development itself—both in terms of hormone changes and concurrent social experiences—shapes adolescent development and presumably later behavior.

Given the intriguing findings to date on the contributions of biological factors to adolescent social behavior, it will be exciting for future work to extend this line of investigation to individual differences in the clan of puberty and social behavior. Just as it is crucial to describe normal, mean-level developmental patterns of boyish behavior, it is important to examine the diversity of trajectories through this developmental period. Boyhood is a determinative time for identity, status, and functioning, and information technology is also a time in which many long-term behavior patterns, including several forms of psychopathology (Paus, Keshavan, & Giedd, 2008), first sally. With more careful attention to the biological and social bases for behavior, more than developmental appreciation of social behavior, and more detailed examination of pubertal influences on behavior, nosotros will have an opportunity to deepen understanding of primal aspects of human being development in means that have great clinical and social policy relevance. Advancing our understanding of the neurobehavioral underpinnings of adolescent vulnerabilities related to affective changes at puberty has implications relevant to a wide range of behavioral and emotional wellness bug with onset in adolescence. A deeper, more mechanistic understanding of these maturational problems can provide leverage for developing more effective early on interventions, including both clinical and policy level efforts. These are most evident in relation to sensation-seeking, risk-taking, reckless behaviors, booze and other substance use issues (see Windle, et al., 2008), accidents and relevant driving policies (come across Dahl, 2008), aggression, health problems related to risky sexual behaviors, and the evolution of affective disorders (see Steinberg, et al., 2006).

Footnotes

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