Brain and Cognition xxx (2014) xxx–xxx

Contents lists available at ScienceDirect

Brain and Cognition journal homepage: www.elsevier.com/locate/b&c

Risk, adaptation and the functional teenage brain Howard Sercombe School of Applied Social Sciences, University of Strathclyde, 6th Floor, Lord Hope Building, 141 St James Road, Glasgow G4 0LT, United Kingdom

a r t i c l e

i n f o

Article history: Available online xxxx Keywords: adolescence risk brain adaptive discourse youth evolution

a b s t r a c t Over the last decade, the propensity for young people to take risks has been a particular focus of neuroscientific inquiries into human development. Taking population-level data about teenagers’ involvement in drinking, smoking, dangerous driving and unprotected sex as indicative, a consensus has developed about the association between risk-taking and the temporal misalignment in the development of reward-seeking and executive regions of the brain. There are epistemological difficulties in this theory. Risk, the brain, and adolescence are different kinds of objects, and bringing them into the same frame for analysis is not unproblematic. In particular, risk is inextricably contextual and value-driven. The assessment of adolescent behaviour and decision-making as ‘sub-optimal’, and the implication that the developmental schedule of the teenage brain is dysfunctional, is also reassessed in terms of evolutionary development of the individual, the family and the human community. The paper proposes a view of adolescent development as adaptive, and a focus on young people’s capacities in the profile of the needs of the community as a whole. Ó 2014 Elsevier Inc. All rights reserved.

1. Introduction A Thursday afternoon, the first warm afternoon of the spring. After months of a Scottish winter’s grey confinement, it was time to take the motorcycle out for a long run. Just on sunset, with the Ducati’s drumbeat exhaust reverberating off the walls, I pulled into the car park of a restaurant built into the dungeons of a thirteenth-century castle deep in the Campsie Fells. The only other people in the restaurant left a few minutes after I arrived, leaving just me and the 18 year old waitress. We struck up a conversation, as you do, about motorcycles in the first instance. She did not like them. I asked if someone had frightened her, and she said yes – her dad. She had gone for a ride with him and he had gone fast and leaned over far and she got frightened and had not got on a motorcycle again. She lived in the village. They had moved there when she was fourteen. She was on a gap year, out of school, working out what to do next. She wanted to move out of the village, to study in Glasgow, but was full of trepidation about leaving home and living on her own. ‘You’re not a risk-taker, are you?’ I said. ‘No’ she laughed. ‘I’m not. I mean, who has their gap year at home?’ Accounts of the neuroscience of adolescent risk often begin with a narrative like this, or more precisely, a narrative exactly the opposite of this (Dobbs, 2011; Landau, 2011; Steinberg, 2004b). According to researchers in this field, adolescence is ‘characterised by suboptimal decisions’ (Casey, Jones, & Hare, 2008) and risk-taking among adolescents is conventionally presented as high E-mail address: [email protected]

level, frequent, and typical. Opening paragraphs in articles about teenagers, risk and the brain repeatedly foreground drinking, or driving recklessly, or taking illegal drugs, or unprotected sex. This is cited as the typical teenage experience, and forms the context within which neuroscientific studies of risk and reward take place. While wide variability in risk taking behaviour is sometimes acknowledged (Samanez-Larkin, Kuhnen, Yoo, & Knutson, 2010), the general assumption of a high risk taking profile for adolescents nevertheless prevails. However, clinical youth work experience finds that the timidity of my Highland waitress is not unusual among teenagers. Official statistics confirming that young people disproportionately drive drunk, take illegal drugs or engage in unprotected sex (Casey et al., 2008; Chein, Albert, O’Brien, Uckert, & Steinberg, 2011; Steinberg, 2008) obscure the equally valid statistical reality that most young people do none of these things (Romer, 2012). The adolescent of the musicals and the movies, the ‘noisy, crazy, dirty, lazy loafers’ of Bye Bye Birdy (Stewart & Adams, 1963), or the motorcycle daredevils of Rebel Without a Cause (Ray, 1955) might get the publicity and the attention, but the teenage world is full of boys and girls like her. There is an even larger number of young people who might like a bit of excitement, to challenge the otherwise suffocating domination that pervades their lives, but do not ever do anything that seriously threatens their lives or livelihoods. Even the most risk-prone adolescents are not taking risks most of the time. Most of the time, they are sitting in highly-controlled environments doing what they are told. As population statistics indicate, young people are mostly competent about risk – the survival rate for teenage boys in the UK is

0278-2626/$ - see front matter Ó 2014 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.bandc.2014.01.001

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001

2

H. Sercombe / Brain and Cognition xxx (2014) xxx–xxx

around 99.96% (UK National Statistics 2012), despite the apparent prevalence of life-threatening sub-optimal decision-making. A number of commentators have argued that there is a danger of over-deterministic, over-simplified and over-generalised accounts of the mechanics of risk taking behaviour, and an understandable, but unbalanced focus on the pathological: on dangerous, deleterious, deviant risk-taking in the young (Ellis et al., 2012; Johnson, Blum, & Giedd, 2009; Moshman, 2011). Morality is not absent from the picture either: the fact that most analyses focus on drinking, smoking, taking drugs and having sex (rather than riding horses, for example (Nutt, 2009)) indicates that it is not merely a question of the highest risks for death or injury. It may well be that young people have a greater propensity to take risks than older populations. There are a range of sociological and psychological reasons as to why the profile of risk taking among teenagers might be different to that of older people. Young people have fewer possessions, less of a stake in the status quo, they do not have positions of power and status to protect. Experience changes our approach to risk: in both directions. Indeed, we should expect differences in brain architecture between young people and older people on the grounds of neuroplasticity alone. Alongside the differential circuits resulting from different prior experiences, young people and older people also inhabit different ecological spaces, and would be expected to have different brains because of that. But it may also be, as current orthodoxies in neuroscience suggest, that in the biological trajectory of human development, the teenage brain deals differently with risk than others’ brains do. This paper has been written in the context of a conversation about adolescence, the brain and risk: and from the perspective of a sociologist and youth worker. While supportive of the potential for contemporary neuroscience to add to our understanding of ourselves, I argue for more care in approaches to these questions, a clearer and cleaner epistemological approach. I am especially wary of the insertion of categories of value and morality into the science, and argue that a more consistent approach to the biology might mitigate against pathologising views of young people. Notwithstanding the occasional rare (and tragic) fatality, we would expect the primary assumption from within a biological perspective to suggest that if there is biologically-driven risk-taking at the population level, it is functional both for the individual and their community (Dobbs, 2011). As a social theorist and as an advocate for young people, I have been concerned at the way that discourses of risk have the potential to feed into youth policy in ways that are restrictive and prejudicial (Ellis et al., 2012; Payne, 2012b). Young people need the neuroscience to be clean and clear, especially given its influence on parenting, education and public policy. Functional Magnetic Resonance Imaging (fMRI) is a powerful cultural instrument, and needs to be operationalised at the level of public discourse with great care (Racine, Bar-Ilan, & Illes, 2005).

2. Neuroscientific research on adolescents, risk and the brain The empirical basis for our understanding of the neuroscience of risk in adolescence rests substantially on fMRI studies involving the subject being scanned while engaged in a simulation of risktaking behaviour, typically playing a computer game that offers varying rewards according to the risk taken within the game. In reported studies (Chein, Albert, O’Brien, Uckert, & Steinberg 2011; Galvan, Hare, Voss, Glover, & Casey, 2006; Segalowitz et al., 2012; Somerville, Hare, & Casey, 2011; Steinberg, 2007, 2010), this work shows a different pattern of activation in various regions of the brains of young people compared to either children or young adults. Specifically, for teenagers engaged in risk-taking

simulations, activation of the reward centres of the brain (the ventral striatum, especially the nucleus accumbens, Nacc) is focused and strong, and activation of the centres responsible for executive function (the pre-frontal cortex, PFC) more diffuse. These data receive corroboration from other work, like Beatriz Luna’s saccade/ anti-saccade testing (Luna, Garver, Urban, Lazar, & Sweeney, 2004; Luna, Padmanabhan, & O’Hearn, 2010; Luna et al., 2001), which also shows that a different pattern of response to stimulus can be seen in fMRI scans of the brain. These data are aligned with behavioural and epidemiological studies of teenagers and risk taking to constitute a narrative regarding risk, the adolescent, and the brain: namely, that, as the adolescent brain develops over the teenage years into its adult configuration, a temporal disconnect occurs between the development of the reward centres of the brain and those responsible for executive function, including rational consideration and judgment (the pre-frontal cortex – see Ernst, this issue). This disconnect results in an increased tendency for young people to take risks. This has been expressed metaphorically in the literature as ‘all gas and no brakes’ (Casey, Jones, & Somerville, 2011; Payne, 2012a) and has been translated into a number of other epistemological spheres, including parenting (Feinstein, 2010; Landau, 2011; National Institute of Mental Health., 2011; Steinberg, 2011), pedagogy (Howard-Jones, 2008; NSW Department of Education, 2006), and the law (Haider, 2005; Steinberg, 2009; Steinberg, Cauffman, Woolard, Graham, & Banich, 2009). There is some recognition that the actual practice of decisionmaking regarding risk for adolescents is unlikely to be simply a function of suboptimal pairing of the Nacc and the PFC. Monique Ernst’s triadic theory suggests that the activation of the amygdala in decision-making about risk is also likely to be significant (Ernst, Pine, & Hardin, 2006). Intuitively, risk-taking involves more than the anticipation of a reward: serious decisions about risk will involve some anxiety and are likely to involve at least avoidance systems. In time, we are likely to identify a broad network of connections within the brain implicated in decisions about risk, in which the Nacc/PFC nexus may be important, but may not be determinative in every risk-decision event (Insel, 2010; McIntosh, 2000; Pfeifer & Allen, 2012; Shermer, 2008; Uttal, 2002). For the moment, however, it constitutes the dominant narrative about the adolescent brain and risk-taking behaviour. 3. The adolescent brain: liability or asset? According to epistemologies that see adolescence as a biological feature of human development, the distinctive elements of adolescence are a product of evolutionary processes, specifically natural selection (Ellis et al., 2012; Hawley, 2011; Weisfeld & Berger, 1983). Presumably, from the point of view of evolutionary psychology, homo sapiens has survived because of adolescence (including the traits the neuroscience is trying to describe), not in spite of it. Biologist David Dobbs argues: Selection is hell on dysfunctional traits. If adolescence is essentially a collection of them—angst, idiocy, and haste; impulsiveness, selfishness, and reckless bumbling—then how did those traits survive selection? They couldn’t. . . [Dobbs (2011)] In an interview on NPR in September 2011, in conversation with B.J. Casey and David Dobbs, Jay Giedd argued that . . .the teen brain is not a broken or defective adult brain. It’s been exquisitely forged by the forces of our evolutionary history to be a very good teen brain. It’s different than children, it’s different than adult, but it’s not broken. [Giedd, in Conan (2012)]

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001

H. Sercombe / Brain and Cognition xxx (2014) xxx–xxx

The ways in which the adolescent brain works optimally in terms of the things that an adolescent brain needs to do is only beginning to emerge as a research interest (Conan, 2012). Volk and Atkinson (2013) make a similar point abut childhood. Neuroscience is indicating something about the teenage brain that is different compared to the adult brain. This kind of disposition may have expression in some teenagers in drinking, smoking, use of illegal drugs and unprotected sex. But it may also manifest in freestyle skiing or playing contact sports; in walking up to a group of people at a new school, club or party, trying a new hair or clothing style, or making up a new way to do music, or starting a business. Or, indeed, in taking up oppositional stances against despotic governments, or maintaining a principled ethical stance in a hostile environment. You could call this risk-taking. But to do so creates the epistemological problem that risk as a category is value-driven and so crosses moral and scientific epistemologies (see below). The disposition in question is broader than risk-taking: it may be expressed in risk-taking, but may also be expressed in a range of other novelty-seeking or ‘what-if’ activities. It is a quality of being open, prepared to try new things, being ‘on for it’. A given individual could be highly responsive with respect to this disposition but actually (for example by pursuing high-novelty but low-risk activities, or by carefully scaffolding their excitement-seeking behaviour) take very few risks. To be epistemologically consistent, the terminology also needs to be value- neutral. I am going to call that quality of action extension. 3.1. The function of risk /sensation/novelty seeking in the personal trajectory of the individual An influential stream of theory in adolescent development has characterised the teenage years in terms of the achievement of a range of ‘developmental tasks’ including leaving home to set up an independent household, leaving school and becoming economically self-sufficient, leaving the parental family unit and establishing a family unit of one’s own (Havighurst & Dreyer, 1975; Poole & Goodnow, 1990). All of these processes are deeply culturally specific, and some may not exist in different communities. Across societies, however, there is the drive for agency: to become an actor in one’s own life, rather than a passive spectator of it. White (1959) argues that agency (he calls it ‘competence’) is a fundamental need. The language of agency is becoming increasingly common in discussions of adolescence (Beyers, Goossens, Vansant, & Moors, 2003; Bucholtz, 2002; Sylwester, 2007; Walls & Little, 2005), perhaps displacing the not unrelated (but arguably overly individualistic) Eriksonian concept of identity formation. I have argued elsewhere (Sercombe, 2010) that agency is what the teenage years are about: that teenagers are agency-machines in the same way that younger children are learning-machines. If this is so, then extension is an essential quality in the process by which young people find their way in the world, in various and sometimes complex ways leave the protective but constraining structures of the parental circle and establish an autonomous, inter-dependent place in their communities (see below). This complexity includes intra-familial power dynamics. Young people develop agency while embedded in an institution in which they do not have the power, and where those who do have the power may not understand or support the need for agency or its particular manifestations. If a cardinal rule of politics is that the people who have the power rarely give it up willingly, agency will often need to be fought for. Resistance, subversion, deception, secrecy, limited communication, and disputation may be necessary processes for young people to ‘win space’ for the agency project (Cohen, 1980). Within this, apparently ‘sub-optimal’ acts may have important symbolic significance (Baumrind 1987; Ellis et al., 2012;

3

France, 2000; Hall & Jefferson, 1976; Lightfoot, 1997). The symbolic function of risk-taking behaviour in the teenage years is often not recognised, or subsumed under the ubiquitous category of ‘peer pressure’. Symbolic acts of extension send a message to peers and/or to dominant adults in their lives that the individual is now, or is in process of becoming, their own person (Ellis et al., 2012; Lyng, 1990). Too much compliance for a teenager is also risky. 3.2. The function of extension in genetic diversity While the literature on evolutionary elements within adolescent development are not well developed (Hawley, 2011), several researchers have begun to explore this dimension. Spear (2000) and Dobbs (Dobbs, 2011) talk about the evolutionary pressure to leave the family of origin, to ‘go out’ thereby broadening the range of possible mates and preventing inbreeding (DeLisi & Beaver, 2011). Dobbs argues that leaving home is one of the most difficult things an individual ever has to do. The capacity to push outside of the familiar, to take risks, is essential in this process. According to Steinberg (2008), extension may also be significant in mate selection, especially for young men. ‘It makes biological sense for males to engage in those behaviours that attract females and for females to choose males most likely to bear offspring with high prospects of surviving and reproducing themselves’ (Steinberg, 2008, p. 87). 3.3. The function of extension in adaptation to social change It has long been argued that human communities are conservative, while environments (technological, political, ecological, climatic) can change quickly and dramatically (Marx, 1858/2005). Ruth Benedict discussed the impact of environmental change on intergenerational relations, arguing that strong peer group orientation and concomitant cultural gaps between generations arose specifically in periods of rapid change (Benedict, 1935). In such circumstances, the young found that their elders did not have the answers to key survival questions in the new environments, so were forced to develop solutions of their own which may not be compatible or congruent with the approaches of their elders. A corollary of this is to consider the role of the capacity for extension in processes of social change. Emerging into adulthood in the contemporary environment, young people need to adapt and develop social forms which make sense in a globalised, computerised, climate-changing, postmodern, ‘liquid’ world (Bauman, 2000). The solutions found by their parents may not be relevant, sufficient or competent to adapt to a changed environment. The retention of the capacity for new neuronal connection in the teenage years, inhibited later by processes of myelination (Kuhn, 2006; Sercombe & Paus, 2009; Spear, 2000), may also serve a key function in facilitating adaptive responses to changed circumstances at the generational level. This argument connects to the role of young people in social change. The current form of Western society is significantly a product of social reforms insisted on by young people of the ‘baby boomer’ generation of the 1960s and 1970s, developed in reaction to the generation in power immediately after World War II and the circumstances of the long boom, the consumer revolution and the contraceptive pill. Current social change in Middle East, the socalled ‘Arab Spring’ is predominantly driven by young people. There are sociological reasons for this – as I noted above, young people generally have fewer responsibilities for dependents, and have fewer economic and political assets, so less to lose – but the architecture of the young brain may also be significant in interaction with these factors. The capacity for extension, the willingness to innovate, to experiment, to ‘just do it’ may add to this structural flexibility in

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001

4

H. Sercombe / Brain and Cognition xxx (2014) xxx–xxx

order to optimise the potential for innovation, adaptation and change. As the rising generation ‘matures’ and moves into positions of economic and political power, these emergent cultural solutions become hardwired into the cultural fabric of the society. According to Wadsworth (2011), all living systems are characterised by the dialectic of stability and change, of homeostasis and adaptation. As living systems, along with the stability and efficiency of older brains, communities may depend for their survival on the flexibility and capacity for extension of the teenage brain. 3.4. The function of extension in the physical survival of communities The process of evolution has shaped homo sapiens as a social species (Flinn, Quinlan, Coe, & Ward, 2007). No single individual, or kind of individual, has evolved to be optimal. Diversity facilitates division of labour and function, which enables the social group to have a much wider range of fitness than would be possible at an individual level (Kappeler & van Schaik, 2002; McGlynn, 2012; Traniello & Rosengaus, 1997). The process of human development is not just a question of a social unit providing a host environment while an individual member’s capacities are assembled into an optimal form that makes them useful somewhere in the third or fourth decade of life. Human beings, as members of a social species, have evolved in communities, engaging the various capacities of men and women, old people, people of middle age, young adults, adolescents, and children (understanding that this process occurs also within a cultural and political matrix). Individual developmental trajectories are important in this process, but so is the contribution of varying capacities across the lifespan. Understanding the adolescent brain means understanding it in the context of the range of capacities that it offers to human survival at the individual level and at the level of human communities. Rather than a product of an unfinished, immature brain, extension is not only arguably an essential adaptive quality for the individual, but may also be beneficial for the community, for society more broadly, and for the species. The focus on the ‘drinking, smoking, sex and fast cars’ canon of risk-taking behaviour has tended to obscure the frequent obligation of young people to take more serious (and more altruistic) risks. Volunteering for military service in times of war, often against the wishes of parents, tends not to be canvassed in discussions of the nucleus accumbens, the PFC and ‘sub-optimal decision-making’. For much of human history, the survival of communities has depended on the willingness and capacity of young men in particular to put themselves in harm’s way (Crook, 1998; Sercombe & Crory, 2010; Wilson & Daly, 1993). Communities that for whatever reason did not have enough people in their teens and twenties would have been vulnerable to extinction. It is entirely conceivable that the capacity for extension in young people constitutes a key evolutionary mechanism for the physical survival of human communities. 3.5. The functional teenage brain: evidence from paleobiology An inquiry into the age-structure of human societies in prehistoric periods also puts into question the proposition that young people are biologically predisposed to sub-optimal decision making, and indeed the general discourse of ‘immature brains’, and that responsibility for decision-making needs to be entrusted to those whose prefrontal cortices are more developed (Moshman, 2011). A range of archaeological findings from around the world indicate that in the prehistoric period, there would simply have been too few people in this more mature age group to do the work. For example, analysis of Early Bronze Age remains of the population of the Franzhausen valley in Austria indicate 20–30 years as the most common age of death. Cemeteries indicate very few

people in the Mature Adult category, and almost no old people (Appleby, 2011). Ackroyd, Lucy, Pollard, and Roberts (1999) indicate that while current methods probably underestimate the age of prehistoric populations to a degree, studies of skeletal remains indicate that the most common age of death would have been in the mid-20s, with very few individuals living beyond 50. Their review of previously published studies included 700 year old skeletal material from Pecos Pueblos, New Mexico, which showed an average age at death of 25 years. A thousand-year old cemetery at Libben, Ohio, indicated a population with an average life expectancy of 20 years, with only 10–15% of the population living beyond 40, and almost none beyond 55. A study of 342 individuals from a cemetery in Orkney, in the Shetland Isles off Scotland, similarly pointed to an average life span of 25 years, with very few living beyond 50. It seems clear from this evidence that 40 is the old 80, and that the weight of responsibility for human survival in these communities rested with people in their teens and twenties. No doubt the brains of teenagers a thousand years ago would have been different from today’s. Our understanding of neuroplasticity would suggest that the forces of environment, including climate, diet, disease, the matrix of threat and security, social forms (including kin) and social expectations, the cultural organisation of sexuality and a myriad of other elements of social and physical ecology would have shaped the brain in particular ways. Epigenetics would suggest genes associated with brain development may also have had a different pattern of expression (Hawley, 2011; Paus, 2013). But at the very least this evidence indicates that a society substantially in the hands of young people would not necessarily be headed for disaster, and reinforces the principle that human societies have survived because of the capacities of the adolescent brain, not in spite of them. It indicates that confidence in the competence of young people might not be misplaced, at least at the biological level. 4. Epistemological questions: the brain, adolescence and risk Alongside these biological questions, the research raises some significant epistemological questions. The neuroscience which is the subject of this paper involves knowledge about risk, the adolescent, and the brain. These three things are very different kinds of objects. Bringing them into the same analytical frame (i.e. experimental science) is not necessarily epistemologically straightforward, and involves a range of caveats which are not always articulated in the literature. At the risk of stating the obvious, some brief elaboration of the epistemological assumptions is worthwhile. 4.1. The brain The brain is an empirical object, constituted (in this context) within epistemologies of medical and biological science. It is in principle observable through the senses, though in practice, direct observation is not possible in live subjects because exposing the brain places the subject at risk of death. In any case, as a chemical-electrical system rather than a physical–mechanical one (like the heart) its processes are not available for direct observation even if it could be safely exposed. Observation occurs indirectly, through the measurement of proxies for activity such as (in the case of fMRI) the magnetic pulses which indicate differential concentration of oxygen-depleted blood in various regions of the brain (the blood-oxygen-level-dependent effect, BOLD), reconstituted as images through computer imaging software (Shermer, 2008). Because all parts of the brain use oxygen all of the time, a judgment call needs to be made as to what level of oxygen uptake constitutes a significant level of brain activity, and the equipment calibrated to exclude signals below that level.

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001

H. Sercombe / Brain and Cognition xxx (2014) xxx–xxx

A range of assumptions have been identified in the literature (Poldrack, 2010), notably: 1. Behaviour can be described in terms of discrete component operations such as reward-seeking, or impulse inhibition. 2. The brain is functionally localised: different discrete sites or modules within the brain correspond to different component operations. 3. The amplitude of activity, measured by oxygen uptake, is a measure of efficacy. Structures drawing low levels of oxygen are understood not to be significant in the activity. 4. The ‘focus’ of activity, in terms of its containment within a specific area, and its intensity, is a measure of efficacy or ‘maturity’. These assumptions are also currently in question (Shermer, 2008), and uncertainty regarding their validity does constitute a caveat in the assessment of knowledge about the brain which depends on fMRI. Structural MRI works on a different set of assumptions, and is not so affected. This way of observing the brain does not give access to thoughts or thinking. Currently, thoughts are not the kind of object that can be operationalised within this epistemology. Brain activity can be measured while a person is thinking (as determined by other means such as a self-report) but a BOLD signal is not a thought or set of thoughts, a decision, an assessment or a plan. It is a fundamentally different kind of object. 4.2. The adolescent The adolescent is a discursive object constituted originally within disciplines of psychology (Choudhury, 2010). Attributed in its modern form generally to Hall (1905), the concept of adolescence was a deliberate attempt to constitute a particular kind of human being as a scientific object, an object which could be studied within the epistemologies of the scientific method, as understood within the frame of developmental or life-span psychology (Choudhury, 2010; Schlegel, 2009; Sercombe, 1996; Wyn & White, 1997). It stands in distinction to other epistemological frames for knowing young people, indicated by different lexical forms (teenager, kid, student, youth, young person, youngster, young American, juvenile) (Sercombe, 1996). The idea of adolescence fits within a teleological conception of the trajectory of human life as an immutable series of distinctive stages, each qualitatively different from those before and after, although there is no agreement on the number of these stages nor their distinctive qualities (Sercombe, 1996). Adolescence is understood as one of these stages, qualitatively distinct from childhood and adulthood. Generally (though not exclusively), the constitutive features of adolescence are understood to be biologically driven. While it is not reasonable to dispute the existence of the brain, it is perfectly reasonable to dispute the existence of adolescence as an object: that is, as a universal, biologically constituted stage of life, qualitatively different from childhood before and adulthood after (Allen, 1968; Bessant, Sercombe, & Watts, 1998; Epstein 2007; France, 2000; Griffin, 1993; Moshman 2011; White & Wyn, 1997). There do appear to be a number of societies which do not have a recognisable adolescent category, notably where there is no hiatus between puberty and the allocation of adult roles and responsibilities (Epstein 2007; Peterson, 1976; Sieg, 1971; Springhall, 1986), though agreement on that is not universal (Keill, 1964; Schlegel, 2009). It is not unreasonable to reject the idea of discrete ‘stages’, arguing that the progression of different capacities in the human through the life span is emergent and incremental, a result of social learning (Bandura, 1964; Epstein, 2007) or a qualitatively different response to qualitatively different social environments,

5

like going to school (Sullivan, 1953). For some commentators, adolescent is a social category like ‘black’ that exists to justify repression and exploitation of one group of people by another (Hall, Jefferson, & Clarke, 1976; Males 1996; Marsland 1978; Van Moorst, 1983). There is more agreement that the meaning, content and structure (including length) of adolescence is a product of particular social arrangements (Allen, 1968; Bessant, 1993; Choudhury, 2010; Griffin, 1993; Hall et al., 1976; Schlegel, 2009; Sercombe, 1996; Wyn & White, 1997), but ‘adolescence’ is nevertheless an ontologically contested object in a way that the brain is not. The adolescent as an object of scientific investigation is constituted specifically in relation to the adult, and specifically in the problematic nature of its relation to the adult. From G Stanley Hall onwards, adolescence has been understood to be about trouble: for Hall, difficulty (through notions of Sturm und Drang) is built into the nature of adolescence (Choudhury, 2010; Payne, 2012a; Sercombe, 1996; Wyn & White, 1997). Any epistemology brings into focus certain relationships between objects, and prunes away others. Within this frame for understanding the nature of youth and the young, continuities and consistencies between younger and older people are pruned away (Epstein, 2007; Hall et al., 1976; Males, 1996; Van Moorst, 1983). In the concern within scientific epistemologies to establish universal, context-free knowledge, heterogeneity among young people is discarded also: adolescents are constituted as a constitutively homogenous group (in this case, with respect to their brain-based predisposition to risk-taking behaviour), even while exceptions are acknowledged. In the concern with the problematic nature of adolescence, the conventionality, competence, agreeability, sociability, productivity and wisdom of young people also tend to disappear. 4.3. Risk The discourse of risk has become increasingly influential over the last two decades; indeed, Ulrich Beck argues that the production and management of risk is the distinctive feature and dominant social driver in late capitalism (Beck, 1992). Risk is not an empirical object. It is concerned with the probability, through specified events, of loss of some quality of value against some gain or benefit. This may also be expressed as the probability of some harm. As such, it is incontrovertibly valuebased: risk is based on an assessment of the value of goods which might be lost against goods which might be gained (Fischhoff, Watson, & Hope, 1984; Holton, 2004). While the probability of loss (or gain) can be calculated independently of the values of the assessor (Christopoulos, Tobler, Bossaerts, Dolan, & Schultz, 2009), the value of the good cannot. Needless to say, different parties’ assessment of value can vary widely. Risk is relative to opportunity cost. For example, a teenage pregnancy involves a range of opportunity costs as parenthood is substituted for other mutually exclusive potential trajectories. That might include a university degree, a satisfying career, a longer period of exploratory development. In different cultures or communities, however, these goods may not be valued, or may not be available: a university degree may never have been possible for the young parent anyway. The opportunity cost for a teenage pregnancy in that context might be low, and the vast majority of young women in a given community might get pregnant while still in their teens. The alternative to early parenthood might be long-term unemployment, individual isolation, or extended existential uncertainty as to the purpose of life. A teenage pregnancy cannot be dealt with universally as a high risk event (Dalla & Gamble, 1997; McRobbie, 2000). There are then no objective risks, except as risks of something: a risk of death or disease, a risk of loss of earning potential, a risk of

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001

6

H. Sercombe / Brain and Cognition xxx (2014) xxx–xxx

imprisonment, a risk to reputation. At the population level, these become average risks of something. The average risk of something is reasonably a factor in individual decision-making, but not if individual circumstances differ materially from the norm, and not if the ‘something’ is not particularly valued or not reasonably attainable in the specific case. The literature on adolescence and risk seems to presume that the value attached to such things (health, or liberty, for example) is universal, and so risk can be dealt with as if it were objective. There is evidence to indicate that this is not the case (Males, 2009). Health may not be valued if one does not expect to live very long, and history is full of examples of people relinquishing their liberty by voluntarily entering total institutions such as monasteries, or by choosing imprisonment rather than betraying a principle. In experimental work that compares the risk-taking behaviour of adolescents and adults, we cannot assume that a given event, experience or act will project the same risk profile. In Gardner and Steinberg’s classic study of the effect of peers on risk-taking in a driving game (Gardner & Steinberg, 2005), the experiment depends on the value attached to the opinion of one’s peers regarding performance in a computer game being uniform between the two groups (adolescents and adults). The experiment may reveal something about the relative value placed on the opinions of peers, rather than the effect of peers on risk taking. The value attached to the opinion of one’s peers is likely also to be contextual. It might be important in the assessment of skill at a computer game, but not in the choice of career (Dietrich and Kracke, 2009). Galvan et al.’s experiments about the relationship between the Nacc and the PFC (Galvan et al., 2006) used cash rewards. But $25 does not have the same value to a nine year old as it does to a thirty year old. Even for a single individual, the value of $25 fluctuates: it might be more valued next week than it is this week. This creates an epistemological problem. In principle, scientific epistemologies seek to establish knowledge that is value-free and context-free. Risk as an object of study cannot be either. The propensity to take risks might be, but the propensity to take risks is typically accessed from a research point of view through actual or simulated risk-taking behaviour which is value-based.

4.4. Epistemological equivalents All science, indeed all knowledge, is about the exploration of relationships between objects (Dewey, 1906). The difficulty with the research on risk-taking and the teenage brain, especially the research based on fMRI, is that it explores relationships between objects that are constituted in different epistemological fields. In order for this to work, the object in ‘epistemology A’ needs to be translated (and thus transformed) into an object that is recognisable in ‘epistemology B’. Often, however, ‘object A’ (risk, in this case) is treated as though it were an object in ‘epistemology B’ (in this case, science): it is imported, untranslated, into ‘epistemology B’, and stands in as an object in ‘epistemology B’. This is not necessarily problematic; indeed the advancement of knowledge requires such translation. The problem arises when there is no recognition that an object in A is not an object that can be operationalised in B, for example, when creation science looks for the hand of God in the process of evolution. The process of evolution is constituted within an epistemology (that of biological science) that does not and cannot recognise God as an object. There may be some process within evolution, as yet unarticulated, that tends towards genesis or order or symmetry, that might correspond in some way to what we might in theological discourse call God. We might work metaphorically with this, for example, when we call the Higgs boson the God-particle. But they are not the same thing: we do not pray to the Higgs boson or ask it to

forgive our sins. The object changes in its translation from one epistemology to another. The brain is already constituted as an object within scientific epistemologies through the discourse of biological science and medicine. More controversially, the adolescent is also established as an empirical object available for scientific inquiry through the discourse of developmental or lifespan psychology. Epistemological transformation of behaviour from the lived experience of actual young men and women to scientific (and thus context-free) behavioural categories is achieved through the process of statistical aggregation and abstraction achieved through quantitative research. While not uncontested (Fischhoff et al., 1984), this is a well established methodological strategy, and forms a fundamental approach to knowledge creation in the cognitive and behavioural sciences. Through this process, particular, one-off, merely individual elements of human behaviour are eliminated, and shared elements are synthesised through probability statistics into context-free objects so that scientific knowledge about the relationships between them can be established. This is not a criticism: it is the way that science works. Similar processes operate across the social sciences, from sociology to economics. The relationship with risk is more difficult. As I argued above, assessments of risk are inextricably value laden and context-specific. In principle, that creates problems for a science of risk. The probability of a loss can, in principle, be calculated dispassionately, if the parameters are clear. The value of a loss cannot be. The use of measures of value, such as loss of earning potential, life expectancy or GNP may help a little but this measures risk only for those parties for whom these things are valuable. When the question is the risk taking behaviour of individuals, it is the value of the potential loss for those individuals that must constitute the reckoning of risk. This is not individualistic: risk is a socially-constructed phenomenon, and values are necessarily interpersonal and typically shared across cultural groups. But there is no such thing as objective risk in the abstract. There have been attempts in the discourse to substitute objects which are not value-laden. Casey et al’s use of phrases such as ‘suboptimal decision making’ (Casey et al., 2008) is such an attempt. However, without a clear definition of what constitutes optimal decision-making, this appears to be sleight of hand: judgements of the ‘optimal’ appear still to be value-driven. In the study of how brains process risk decisions, a constant series of epistemological transformations are taking place. Valuebased assessments of risk are converted into choice menus for participants in a research study or an experiment. Actions around these menus, via the MRI scanner, are read off as activity in various parts of the brain. This is then read back into value-based assessments of risk. A mistake is made if the extent to which this work is interpretive and translational is not recognised, and if the epistemological transformations are not made explicit. If the researcher does not want the research to be interpretive and translational, risk as an object should be avoided. In practice, this level of epistemological explication is rarely evident in published work. In article after article on adolescence and risk, the research is introduced with a kind of canon of behaviours which stand in as an index of risk: smoking, drinking, unprotected sex, illegal drug use, fighting, or the reckless use of a motor vehicle (Albert & Steinberg, 2011; Gibbons, Helweg-Larsen, & Gerrard, 1995; Pharo, Sim, Graham, Gross, & Hayne, 2011; Ravert et al., 2009; Steinberg, 2004a, 2008). These events are held to be universally and unambiguously risky, enabling statistics to be gathered about the reported incidence of these events or decisions to engage or willingness to engage in these events. For the researcher, the outcome is a context-free register of adolescents’ propensity for risk-taking, which generally involves activities which are understood to be ‘anti-social’ (often a cipher for

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001

H. Sercombe / Brain and Cognition xxx (2014) xxx–xxx

immoral) and to a degree pathological or ‘sub-optimal’. Actual behaviour like this generally cannot be researched neuroscientifically because of the limitations of movement involved in being in a scanner (Johnson et al., 2009). Rather, this profile provides the background against which simulations of risk taking that can be performed in a scanner constitute the experiments on which knowledge of the brain and risk-taking can be formed. The result, however, is a value-driven perspective on young people which constructs them in deficit, in dysfunction, as ‘sub-optimal’. As a result, several commentators have attacked this field of work as ‘bad science’ (Bessant & Watts, 2012; Kelly, 2012; Moshman, 2011; Payne, 2012a,b) or made unflattering comparisons between fMRI based research and phrenology (Bessant, 2008; Diener, 2010; Dobbs, 2005; Poldrack, 2010; Uttal, 2001). 5. Conclusion This paper has not directly addressed the dominant neuroscientific theory about adolescence, risk and the brain, i.e., the temporal disconnect between the maturation of the nucleus accumbens and the prefrontal cortex. The significance of this relationship will no doubt be tested and clarified as the approaches of cognitive neuroscience are refined, and as the body of knowledge is developed. Rather, I have been concerned with the way that risk is operationalised in our understanding of young people and in the nature of being young, and especially the epistemological problems concerned with the importation of value-driven and moral categories into the science through the discourse of risk. This of course does have implications for the theory concerning the Nacc/PFC nexus. I have suggested that we might consider more closely the epistemological transformations that are occurring within scientific practice in this field. The case in question here is the convergence of the discourse of risk and the discourse of adolescence, which tends to construct young people in categories of deficit and dysfunction, in contradiction to biological assumptions about evolutionary process and the power of natural selection. The call for a new approach to adolescent neuroscience which explores the capacity of young people rather than constructing them in deficit seems to be gathering momentum (Conan, 2012; Dobbs, 2011; Johnson et al., 2009; Moshman, 2011; Payne, 2012b; Ellis, 2012). As Johnson, Blum and Giedd argue, . . . the focus on pathologic conditions, deficits, reduced capacity, and age based risks overshadows the enormous opportunity for brain science to illuminate the unique strengths and potentialities of the adolescent brain. So, too, can this information inform policies that help to reinforce and perpetuate opportunities for adolescents to thrive in this stage of development, not just survive. [Johnson et al. (2009, p. 8)] Whether this can be sustained when the discourse of adolescence has the assumption of turmoil built in remains to be seen. It is almost a mantra within the literature that this generation of neuroscience is still in its infancy (DiPietro, 2000; Hyman & Malenka, 2001; Johnson et al., 2009; Kircher & David, 2003). However, despite the preliminary status of our knowledge, the fascination with the human brain, the power of neuroscience’s possibilities and the vividness of the images generated through the fMRI process almost make overreaching inevitable, whether pulled by the public demand for interpretations of behaviour from brain images, or pushed by the temptations of publicity and the competition for research funding. Neuroscience continues to present profound possibilities for our understanding of ourselves and each other. There has already

7

been an impact on our understanding of adolescence. However, the intellectual challenges involved in conceptualising the relationship between an MRI scan and the complex realities of human agency are considerable. Gradually, the epistemological and methodological limitations of fMRI-based cognitive neuroscience in particular are becoming clearer and appropriate conceptual frameworks are being put in place (Johnson et al., 2009). This project is now a matter of urgency if the credentials of this fascinating area of work are to be maintained. References Ackroyd, R., Lucy, D., Pollard, A., & Roberts, C. (1999). Nasty, brutish, but not necessarily short: a reconsideration of the statistical methods used to calculate age at death from adult human and dental age indicators. American Antiquity, 64(1), 55–70. Albert, D., & Steinberg, L. (2011). Judgment and decision making in adolescence. Journal of Research on Adolescence, 21(1), 211–224. Allen, S. (1968). Some theoretical problems in the study of youth. Sociological Review, 16(3), 319–331. Appleby, J. (2011). Bodies, burials and ageing: accessing the temporality of old age in prehistoric societies. Oxford Journal of Archaeology, 30(3), 231–246. Bandura, A. (1964). The stormy decade: Fact or fiction? Psychology in the Schools, 1, 224–231. Bauman, Z. (2000). Liquid modernity. Cambridge: Polity Press. Baumrind, D. (1987). A developmental perspective on adolescent risk taking in contemporary America. New Directions for Child and Adolescent Development, 37, 93–125. Beck, U. (1992). Risk society: Towards a new modernity (M. Ritter, Trans.). London: SAGE. Benedict, R. (1935). Patterns of culture. London: Routledge and Kegan Paul. Bessant, J. (1993). Constituting categories of youth: Towards the 21st century. Melbourne: National Centre for Socio-legal Studies, La Trobe University. Bessant, J. (2008). Hard wired for risk: Neurological science, ‘the adolescent brain’ and developmental theory. Journal of Youth Studies, 11(3), 347–360. Bessant, J., Sercombe, H., & Watts, R. (1998). Youth studies: An Australian perspective. Melbourne: Addison Wesley Longman. Bessant, J., & Watts, R. (2012). The mismeasurement of youth: Why adolescent brain science is bad science. Contemporary Social Science, 7(2), 181–196. Beyers, W., Goossens, L., Vansant, I., & Moors, E. (2003). A structural model of autonomy in middle and late adolescence: Connectedness, separation, detachment, and agency. Journal of Youth and Adolescence, 32(5), 351–365. Bucholtz, M. (2002). Youth and cultural practice. Annual Review of Anthropology, 525–552. Casey, B. J., Jones, R. M., & Hare, T. A. (2008). The adolescent brain. Annals of the New York Academy of Sciences, 1124(1), 111–126. Casey, B., Jones, R. M., & Somerville, L. H. (2011). Braking and accelerating of the adolescent brain. Journal of Research on Adolescence, 21(1), 21–33. Chein, J., Albert, D., O’Brien, L., Uckert, K., & Steinberg, L. (2011). Peers increase adolescent risk taking by enhancing activity in the brain’s reward circuitry. Developmental Science, 14(2), F1–F10. Choudhury, S. (2010). Culturing the adolescent brain: What can neuroscience learn from anthropology? Social Cognitive and Affective Neuroscience, 5(2–3), 159–167. Christopoulos, G. I., Tobler, P. N., Bossaerts, P., Dolan, R. J., & Schultz, W. (2009). Neural correlates of value, risk, and risk aversion contributing to decision making under risk. The Journal of Neuroscience, 29(40), 12574–12583. Cohen, S. (1980). Folk devils and moral panics (2nd ed.). Oxford: Robinson. Conan, N. (2012). Understanding The Mysterious Teenage Brain Retrieved 05.12.12. Crook, P. (1998). Human pugnacity and war: Some anticipations of sociobiology, 1880–1919. Biology and Philosophy, 13(2), 263–288. Dalla, R. L., & Gamble, W. C. (1997). Exploring factors related to parenting competence among Navajo teenage mothers: Dual techniques of inquiry. Family Relations, 113–121. DeLisi, M., & Beaver, K. (2011). Criminological theory: A life-course approach. Sudbury, MA: Jones and Bartlett Publishers. Dietrich, J., & Kracke, B. (2009). Career-specific parental behaviors in adolescents’ development. Journal of Vocational Behavior, 75, 109–119. Dewey, J. (1906). The experimental theory of knowledge. Mind, 15(59), 293–307. Diener, E. (2010). Neuroimaging: Voodoo, new phrenology, or scientific breakthrough? Introduction to special section on fMRI. Perspectives on Psychological Science, 5(6), 714–715. DiPietro, J. A. (2000). Baby and the brain: Advances in child development. Annual Review of Public Health, 21(1), 455–471. Dobbs, D. (2005). Fact or phrenology? Scientific American Mind Retrieved 05.12.12. Dobbs, D. (2011). Beautiful brains. National Geographic Magazine, (October). Retrieved from .

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001

8

H. Sercombe / Brain and Cognition xxx (2014) xxx–xxx

Ellis, B. J., Del Giudice, M., Dishion, T. J., Figueredo, A. J., Gray, P., Griskevicius, V., et al. (2012). The evolutionary basis of risky adolescent behavior: Implications for science, policy, and practice. Developmental Psychology, 48(3), 598–623. Epstein, R. (2007). The case against adolescence: Rediscovering the adult in every teen. Sanger California: Quill Driver Books. Ernst, M., Pine, D. S., & Hardin, M. (2006). Triadic model of the neurobiology of motivated behavior in adolescence. Psychological Medicine, 36(3), 299–312. Feinstein, S. (2010). Inside the teenage brain: Parenting a work in progress. Lanham, Maryland: Rowland & Littlefield Education. Fischhoff, B., Watson, S. R., & Hope, C. (1984). Defining risk. Policy Sciences, 17(2), 123–139. Flinn, M. V., Quinlan, R. J., Coe, K., & Ward, C. V. (2007). Evolution of the human family: Cooperative males, long social childhoods, smart mothers. In C. A. Salmon & T. K. Shackleford (Eds.), Family relationships: An evolutionary perspective (pp. 16–38). Oxford: Oxford University Press. France, A. (2000). Towards a sociological understanding of youth and their risktaking. Journal of Youth Studies, 3(3), 317–331. Galvan, A., Hare, T. A., Parra, C. E., Penn, J., Voss, H., Glover, G., et al. (2006). Earlier development of the accumbens relative to orbitofrontal cortex might underlie risk-taking behavior in adolescents. The Journal of Neuroscience, 26(25), 6885–6892. Galvan, A., Hare, T., Voss, H., Glover, G., & Casey, B. J. (2006). Risk-taking and the adolescent brain: Who is at risk? Developmental Science, 10(2), 8–14. Gardner, M., & Steinberg, L. (2005). Peer influence on risk taking, risk preference, and risky decision making in adolescence and adulthood: An experimental study. Developmental Psychology, 41(4), 625–635. Gibbons, F. X., Helweg-Larsen, M., & Gerrard, M. (1995). Prevalence estimates and adolescent risk behavior: Cross-cultural differences in social influence. Journal of Applied Psychology, 80(1), 107–121. Griffin, C. (1993). Representations of youth the study of youth and adolescence in Britain and America. Cambridge: Polity. Haider, A. (2005). Roper v. Simmons: The Role of the Science Brief. Ohio State Journal of Criminal Law, 3, 369–377. Hall, G. S. (1905). Adolescence: Its psychology and its relations to physiology, anthropology, sociology, sex, crime, religion and education. London: Sydney Appleton. Hall, S., & Jefferson, T. (Eds.). (1976). Resistance through rituals. London: Hutchinson. Hall, S., Jefferson, T., & Clarke, J. (1976). Youth: A stage of life? Youth and Policy (17). Havighurst, R. J., & Dreyer, P. H. (1975). Youth. Chicago: University Of Chicago Press. Hawley, P. H. (2011). The evolution of adolescence and the adolescence of evolution: The coming of age of humans and the theory about the forces that made them. Journal of Research on Adolescence, 21(1), 307–316. Holton, G. A. (2004). Defining risk. Financial Analysts Journal, 60(6), 19–25. Howard-Jones, P. (2008). Potential educational developments involving neuroscience that may arrive by 2025. December. Beyond Current Horizons Retrieved 30.11.12. Hyman, S. E., & Malenka, R. C. (2001). Addiction and the brain: the neurobiology of compulsion and its persistence. Nature Reviews Neuroscience, 2(10), 695– 703. Insel, T. R. (2010). Faulty circuits. Scientific American, 302(4), 44–51. Johnson, S. B., Blum, R. W., & Giedd, J. N. (2009). Adolescent maturity and the brain: The promise and pitfalls of neuroscience research in adolescent health policy. Journal of Adolescent Health, 45(3), 216–221. Kappeler, P. M., & van Schaik, C. P. (2002). Evolution of primate social systems. International Journal of Primatology, 23(4), 707–740. Keill, N. (1964). The universal experience of adolescence. New York: International Universities Press. Kelly, P. (2012). The brain in the jar: A critique of discourses of adolescent brain development. Journal of Youth Studies, 15(7), 944–959. Kircher, T., & David, A. (2003). The self in neuroscience and psychiatry. Cambridge: Cambridge University Press. Kuhn, D. (2006). Do cognitive changes accompany developments in the adolescent brain? Perspectives on Psychological Science, 1(1), 59–67. Landau, E. (2011). Why teens are wired for risk. October 19, Retrieved 30.11.12. Lightfoot, C. (1997). The culture of adolescent risk-taking. Guilford Press. Luna, B., Garver, K. E., Urban, T. A., Lazar, N. A., & Sweeney, J. A. (2004). Maturation of cognitive processes from late childhood to adulthood. Child Development, 75(5), 1357–1372. Luna, B., Padmanabhan, A., & O’Hearn, K. (2010). What has fMRI told us about the development of cognitive control through adolescence? Brain and Cognition, 72(1), 101. Luna, B., Thulborn, K. R., Munoz, D. P., Merriam, E. P., Garver, K. E., Minshew, N. J., et al. (2001). Maturation of widely distributed brain function subserves cognitive development. Neuroimage, 13(5), 786–793. Lyng, S. (1990). Edgework: A social psychological analysis of voluntary risk taking. American Journal of Sociology, 851–886. Males, M. (1996). The scapegoat generation: America’s war on adolescents. Philadelphia: Common Courage Press. Males, M. (2009). Does the adolescent brain make risk taking inevitable?: A skeptical appraisal. Journal of Adolescent Research, 24(3), 3–20. Marsland, D. (1978). Sociological explorations in the service of youth. Leicester: National Youth Bureau.

Marx, K. (1858/2005). Grundrisse: Foundations of the critique of political economy: ePenguin. McGlynn, T. (2012). How does social behavior evolve? Nature Education Knowledge, 3(10), 69–71. McIntosh, A. R. (2000). Towards a network theory of cognition. Neural Networks, 13(8), 861–870. McRobbie, A. (2000). Teenage mothers: A new social state. In A. McRobbie (Ed.), Feminism and youth culture (2nd ed. Houndmills: Macmillan. Moshman, D. (2011). Adolescents are young adults, not immature brains. Applied Developmental Science, 15(4), 171–174. National Institute of Mental Health. (2011). The teen brain: Still under construction. Retrieved 30.11.12. NSW Department of Education and Training. (2006). Closed for construction – adolescent brain development in the middle years. Retrieved 30.11.12. Nutt, D. J. (2009). Equasy – a harmful addiction. Journal of Psychopharmacology, 23(3). Retrieved from . Paus, T. (2013). Population Neuroscience. Heidelberg: Springer. Payne, M. A. (2012a). ‘‘All Gas and No Brakes!’’: Helpful metaphor or harmful stereotype? Journal of Adolescent Research, 27(1), 3–17. Payne, M. A. (2012b). Are all teenagers emotionally illiterate? Charting a neuroscientific storying of normative deficit. Emotional and Behavioural Difficulties, 17(2), 143–155. Peterson, J. (1976). Mississippi Choctaw Youth. In E. Fuchs (Ed.), Youth in a changing world: Cross-cultural perspectives on adolescence. The Hague: Mouton. Pfeifer, J. H., & Allen, N. B. (2012). Arrested development? Reconsidering dualsystems models of brain function in adolescence and disorders. Trends in Cognitive Sciences. Pharo, H., Sim, C., Graham, M., Gross, J., & Hayne, H. (2011). Risky business: Executive function, personality, and reckless behavior during adolescence and emerging adulthood. Behavioral Neuroscience, 125(6), 970–978. Poldrack, R. A. (2010). Mapping mental function to brain structure: How can cognitive neuroimaging succeed? Perspectives on Psychological Science, 5(6), 753–761. Poole, M., & Goodnow, J. (1990). The changing world of children and youth in Australia. Journal of Youth and Child Care, 4(4), 1–8. Racine, E., Bar-Ilan, O., & Illes, J. (2005). FMRI in the public eye. Nature Reviews Neuroscience, 6(2), 159–164. Ravert, R. D., Schwartz, S. J., Zamboanga, B. L., Kim, S. Y., Weisskirch, R. S., & Bersamin, M. (2009). Sensation seeking and danger invulnerability: Paths to college student risk-taking. Personality and Individual Differences, 47(7), 763–768. Ray, N. (Writer), (1955). Rebel without a cause [Film]. USA: Warner Bros. Romer, D. (2012). Adolescent risk taking, impulsivity, and brain development: Implications for prevention. Developmental Psychobiology, 52(3), 263–276. Samanez-Larkin, G. R., Kuhnen, C. M., Yoo, D. J., & Knutson, B. (2010). Variability in nucleus accumbens activity mediates age-related suboptimal financial risk taking. The Journal of Neuroscience, 30(4), 1426–1434. Schlegel, A. (2009). A cross-cultural approach to adolescence. Ethos, 23(1), 15–32. Segalowitz, S. J., Santesso, D. L., Willoughby, T., Reker, D. L., Campbell, K., Chalmers, H., et al. (2012). Adolescent peer interaction and trait surgency weaken medial prefrontal cortex responses to failure. Social Cognitive and Affective Neuroscience, 7(1), 115–124. Sercombe, H. (1996). Naming youth: The construction of the youth category. Unpublished PhD thesis, Murdoch University, Perth. Sercombe, H. (2010). Youth work ethics. Sage Publications Limited. Sercombe, H., & Crory, P. (2010). The situation for young men in contemporary Scotland: A gathering of opinion. The Journal of Youth Work: Research and Positive Practices in Work with Young People (5), 27–36. Sercombe, H., & Paus, T. (2009). The ‘‘teen brain’’ research: implications for practitioners. Youth and Policy, 100 [Spring]. Shermer, M. (2008). Five ways brain scans mislead us. (November 5). Retrieved from . Sieg, A. (1971). Why adolescence occurs. Adolescence, 6, 337–348. Somerville, L. H., Hare, T., & Casey, B. J. (2011). Frontostriatal maturation predicts cognitive control failure to appetitive cues in adolescents. Journal of Cognitive Neuroscience, 23(9), 2123–2134. Spear, L. P. (2000). The adolescent brain and age-related behavioral manifestations. Neuroscience & Biobehavioral Reviews, 24(4), 417–463. Springhall, J. (1986). Coming of age: Adolescence in Britain, 1860–1960. Dublin Gill and Macmillan. Steinberg, L. (2004a). Risk taking in adolescence: What changes and why? Annals of the New York Academy of Sciences, 1021, 51–58. Steinberg, L. (2004b). Risk taking in adolescence: What changes, and why? Annals of the New York Academy of Sciences, 1021(1), 51–58. Steinberg, L. (2007). Risk taking in adolescence new perspectives from brain and behavioral science. Current Directions in Psychological Science, 16(2), 55–59. Steinberg, L. (2008). A social neuroscience perspective on adolescent risk-taking. Developmental Review, 28(1), 78–106. Steinberg, L. (2009). Should the science of adolescent brain development inform public policy? American Psychologist, 64(8), 739. Steinberg, L. (2010). A dual systems model of adolescent risk-taking. Developmental Psychobiology, 52(3), 216–224.

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001

H. Sercombe / Brain and Cognition xxx (2014) xxx–xxx Steinberg, L. (2011). You and your adolescent: The essential guide for ages 10–25. New York: Simon & Schuster. Steinberg, L., Cauffman, E., Woolard, J., Graham, S., & Banich, M. (2009). Are adolescents less mature than adults?: Minors’ access to abortion, the juvenile death penalty, and the alleged APA’’ flip-flop’’. American Psychologist, 64(7), 583. Stewart, M., & Adams, L. (1963). Bye Bye Birdie. Broadway musical production. Sullivan, H. S. (1953). The interpersonal theory of psychiatry. New York: Norton. Sylwester, R. (2007). The adolescent brain: Reaching for autonomy. Corwin Press. Traniello, J. F., & Rosengaus, R. B. (1997). Ecology, evolution and division of labour in social insects. Animal Behaviour, 53(1), 209–213. Uttal, W. R. (2001). The new phrenology: The limits of localizing cognitive processes in the brain. Cambridge, MA: Massachusetts Institute of Technology Press. Uttal, W. R. (2002). Précis of the new phrenology: The limits of localizing cognitive processes in the brain. Brain and Mind, 3(2), 221–228. Van Moorst, H. (1983). Working with youth: A political process beyond the back yard. Sydney: National Workers With Youth Forum.

9

Volk, A. A., & Atkinson, J. A. (2013). Infant and child death in the human environment of evolutionary adaptation. Evolution and Human Behavior, 34, 189–192. Wadsworth, Y. (2011). Building in research and evaluation: Human inquiry for living systems. Left Coast Press. Walls, T. A., & Little, T. D. (2005). Relations among personal agency, motivation, and school adjustment in early adolescence. Journal of Educational Psychology, 97(1), 23. Weisfeld, G. E., & Berger, J. M. (1983). Some features of human adolescence viewed in evolutionary perspective. Human Development, 26(3), 121–133. White, R. W. (1959). Motivation reconsidered: The concept of competence. Psychological Review, 66(5), 297–333. White, R., & Wyn, J. (1997). Rethinking youth. Sydney: Allen & Unwin. Wilson, M., & Daly, M. (1993). Lethal confrontational violence among young men. In N. Bell & R. Bell (Eds.), Adolescent risk-taking (pp. 84–106). Newberry Park: Sage. Wyn, J., & White, R. (1997). Rethinking youth. St Leonards: Allen and Unwin.

Please cite this article in press as: Sercombe, H. Risk, adaptation and the functional teenage brain. Brain and Cognition (2014), http://dx.doi.org/10.1016/ j.bandc.2014.01.001