Understanding Mental Health

High Risk Behaviours


Adolescent brain development and substance use

Adolescence is characterized by significant growth and development and this, across a number of areas. Some behaviours such as those connected with increased independence and autonomy are characteristic of this period. Indeed, many of the behaviours associated with adolescence are related to cognitive maturation and can be explained by the fact that the adolescent brain is not yet fully developed. Research using brain imaging has helped us understand that the areas of the brain responsible for motivation and emotion develop earlier and consequently are more active during this period than those responsible for complex thought (e.g. judgment, planning and foresight) (Society for Neuroscience, 2007). Behavioural manifestations of this include difficulty with delayed gratification and impulse control, and risk-taking behaviours for which adolescents are notorious (Steinberg, 2007). The adolescent brain is also vulnerable because of the way it responds to various substances. Specifically, adolescents are less susceptible to the effects of alcohol, have shorter recovery times (less hangover) and are more sensitive to the effects of social disinhibition than adults, which reinforces substance use in social situations (Spear, 2002). What is more, the adolescent brain is more sensitive to potential damage brought about by the use of substances (Brown et al., 2000).  For these reasons as well as those detailed above, experimentation with substances often occurs during this period. Adolescents are therefore more at risk to develop an addiction simply as result of the period at which they began.


Characteristics of adolescent substance abuse

Adolescent substance abuse is unique in terms of its risks which include rapid progression from first use to abuse and dependence (Winters, 1999), the short period between the first and second diagnosis of substance dependence (Spear, 2002), and the frequency of co-occurring disorders (Kandel et al., 1997, in Muck et al., 2001). Fundamentally different from adults, adolescents also have higher rates of binge drinking, less awareness regarding the problems associated to their use (Battjes et al., 2003) and an increased susceptibility to peer influence (Steinberg, 2004). Also relevant is the correlation between age of first use and rates of dependence: teenagers who start at an earlier age are more at risk of escalating to more serious and problematic use (Grant & Dawson, 1997). In view of the fact that adolescent problems related to substance abuse are more easily identified (e.g. attendance or behaviour at school, relationship with parents), and because most adolescents have not used as long as adults and have not yet experienced the physiological symptoms caused by their use, adolescents are more frequently diagnosed with substance abuse than dependence (Winters et al., 2001). Despite the numerous risks related to the use of substances by this age group, most adolescents who experiment can do so without it ever progressing to substance abuse and/or negatively impacting their lives. Moreover, many adolescents who are at risk will never use substances at all or develop problematic use (Winters et al., 2001; NIDA, 2003). These young people have developed healthy ways of coping that allow them to manage the powerful emotions they face.


Risk and protective factors

For others, it can be difficult to reduce or stop using drugs and alcohol, regardless of the severity of their problems. It can be incredibly challenging for adolescents to change their behaviour when they have been using to self-regulate and do not yet have the capacity to cope with the intense emotions they experience. For this reason, it is especially important to examine the reinforcing qualities of substance use and influences (family, peers) in relation to risk and protective factors which can act alone and/or in combination to shape behaviour. Risk factors are elements that increase the risk of developing an addiction (e.g. parental substance use, high stress, aggressive behaviour, poor impulse control), while protective factors reduce the likelihood that the an addiction will occur (e.g. stable living environment, parental support and involvement, academic achievement, community influence). Risk and protective factors can vary and are not the same from one person to the next; more than simply a physiological reaction to an addictive substance, drug use is often the result of multiple determinants in the teenager’s life (Swadi, 1999). One way to prevent substance use is to increase adolescents` resilience by enhancing protective factors and by reducing risk factors. Intervening early to address risk factors is especially important given the potential long-term impact on the adolescent not only in reducing risk, but also by helping foster positive behaviours (Ialongo et al., 2001).

Some family-related protective factors include:

  • a strong bond between children and their families;

  • parental involvement in a child’s life;

  • supportive parenting that meets financial, emotional, cognitive, and social needs; and

  • clear limits and consistent enforcement of discipline.

(National Institute on Drug Abuse (NIDA) (2003). Preventing Drug Abuse Among Children and Adolescents: A Research-Based Guide for Parents, educators, and Community Leaders, Second Edition.)


Other school-related factors include:

  • success in academics and involvement in extracurricular activities;

  • strong bonds with prosocial institutions, such as school and religious institutions

(National Institute on Drug Abuse (NIDA) (2003). Preventing Drug Abuse Among Children and Adolescents: A Research-Based Guide for Parents, educators, and Community Leaders, Second Edition.)


For more information on substance abuse:

For practical tips and information on prevention and early intervention, click on the CEMH postcard dedicated to this topic:



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