Short Report: Measuring Age-Related Differences in Adolescent Resilience

Author: Tyler Phillips, Research Psychologist and Lead Content Specialist

Adolescence is a time of many rapid and often tumultuous changes. From those in the brain-body system (with hormonal development leading to stark emotional, mental, and physical shifts) to those in the relational world (such as growing conflicts with parents and new, more complex social situations, desires, and challenges among peers), being a teenager means having to adapt quickly, everywhere. This is why adolescence has been flagged as the window in which people are most vulnerable to stress – and the potential for stress to lead to mental illnesses. It is also why promoting resilience among adolescents is critical. 

From a neurobiological standpoint, teenagers’ vulnerability to the effects of stress makes a lot of sense. In the brain, resilience reflects an ability to remain in, or return to, a baseline relaxed physiological state when we encounter challenges, stressors, or obstacles. Usually, when we encounter these things, the amygdala – the seat of quick emotion, especially fear – gets us ready to fight or flee. Then, the prefrontal cortex – the higher-order problem-solver – reassesses the situation and reassures the amygdala that the challenge is not so dangerous, or that we can take care of it in wiser ways. As more rational and effective responses are chosen and executed, calmness returns. However, in adolescence, the amygdala is fully developed but the prefrontal cortex is not. This is why teenagers tend to be emotionally reactive, to make risky decisions, to act on impulses – and to be more vulnerable to the influence of stressors. 

However, adolescence is not a solid, blanket period. Because of the steepness of its trajectory, teenagers can be in very different stages (regarding their brain-body systems) and positions (regarding their psychosocial worlds) year by year. For example, some studies have seen 15-year-olds producing higher levels of cortisol (the stress hormone) than 13-years-olds after encountering the same stressor. Chemical reactions to stimuli therefore alter as teenagers grow. Other studies have found that executive (prefrontal) functions like working memory (the ability to update information as you work on it) and shifting (purposefully changing attention from one topic to another) undergo spurts between 14 and 15, and mature to adult levels just after 17. So, cognitive abilities among teenagers can also be quite different in the span of just one or two years. It may also be the case that their vulnerabilities to stressors, and their capacities and resources for adapting to and growing from them, also fluctuate as the calendar turns over. 

Put differently, it may be that for each year of adolescence, we can observe different profiles or levels of resilience. Fortunately, we can test this hypothesis. Neurozone® recently developed the Neurozone® Adolescent Resilience Index (NARI), a statistically sound, comprehensive, and widely applicable measure of adolescent psychological resilience. Using the NARI, we decided to measure the current resilience levels of students across 4 government schools in Cape Town, South Africa, and to compare their results by year of age. The sample consisted of a total of 545 students, and while it ranged from 12- to 18-years-olds, the ages that were available for comparison were 13, 14, 15, 16, and 17 years. The results are presented below:  

Note, firstly, that all NARI scores, including the average for the whole group, would fall in the ‘Moderate’ range of resilience as measured on the adult version of the Resilience Index. (Because it is a brand new measure, the NARI does not yet have statistically derived categories of adolescent resilience; comparisons of adolescent scores to the adult measure are therefore not precise, but still a useful benchmark.) The scores between the different adolescent ages are therefore not starkly, significantly different. However (and although the sample sizes between groups are not equal), there is a small, interesting trend that is slightly U-shaped. The 13-year-olds had the highest resilience at 66, followed by a drop in 14-year-olds to 61, then a small bump up to 62 for both the 15- and 16-year-olds, and finally a little rise to 65 for the 17-year-olds. 

Although we did not measure anything more than resilience, this trend does seem to resemble related findings from other studies. For example, as mentioned above, 15-years-olds have been found to produce more cortisol (the stress hormone) compared to 13-year-olds, and if that is also true in this sample, it might partly be why the 13-year-olds have the highest resilience here. Their neurochemistry may be relatively more robust against stressors. Other studies have found that, from ages 14 to 17, teenagers tend to experience less negative self-esteem, and tend to grow their capacities for distress tolerance (the ability to accept a situation as it is, even if it is uncomfortable). Having more confidence in oneself, as well as (perhaps even related to) more stoicism in the face of stress, is intimately related to higher resilience – including in adolescents. If this sample also demonstrates these qualities, that may partly explain why we see a rise in resilience from 14 to 17 as well. 

At the same time, the vast majority of resilience and adolescent development research is based in the global North and/or high-income countries. In low- to middle-income countries like South Africa, in which this sample is based, a plethora of factors complicate or adjust the picture. To illustrate, one South African study looked at age-related differences in factors that promote continued engagement at school, which is associated with higher adolescent resilience in under-resourced and highly stress-exposed areas. The researchers found that these teenagers’ perceptions of multiple resources, at multiple levels, combined to predict high school engagement (and resilience) among them. For example, experiencing a high degree of guardian warmth was important for both younger and older adolescents, but the younger adolescents also needed a well-resourced school, while the older adolescents needed competent teachers, in combination with this guardian support, to show a positive trajectory of engagement and resilience. Those (younger and older) adolescents who reported lacking these factors tended to have poorer engagement and resilience trajectories. 

It may be the case, then, that differences in adolescents’ perceived availability of guardian warmth, school resources, competent educators – and perhaps a host of other factors – are at play in our South African sample, influencing the slight U-shaped pattern we observed in resilience scores. The ultimate reasons for why we observed it, however, are not currently accessible. This points to the need to conduct more research into adolescent development in low- to middle-income environments, where under-represented populations face unique challenges. Identifying the factors that hinder and promote adolescent resilience at different ages is essential to curb the development of psychiatric difficulties before adulthood. Thankfully, the Neurozone® Adolescent Resilience Index is one tool that can be of significant service in that endeavor.