50% of chronic mental illness begins by age 14, and 75% by age 24 (National Alliance on Mental Illness). Adolescents experience frequent and intense instances of negative emotions, which are thought to underlie their increased susceptibility to affective disorders, drug abuse, suicide, and accidental deaths during this period (Andersen and Teicher, 2009; Casey et al., 2010). Adolescents are especially vulnerable to emotional volatility, making this a sensitive window for the incidence of affective and substance use disorders, because subcortical limbic regions, such as the amygdala, mature before cortical structures do, resulting in delayed top-down regulation (Casey et al., 2011; Schramm-Sapyta et al., 2009). Because these brain regions mediate emotional behaviour and undergo neuroplastic changes during adolescence, stressful experiences at this time can have long-lasting psychiatric consequences (Andersen and Teicher, 2009; Fuhrmann et al., 2015). The prefrontal cortex and one of its major targets, the amygdala, are crucial processors of aversive and motivational cues (Janak and Tye, 2015; Sierra-Mercado et al., 2011). It is therefore vital to understand the relationship between these circuits, emotional stress, and adolescence.
We aim to dissect the neural underpinnings of adolescent susceptibility to long-lasting emotional dysregulation and hypothesise that the amygdala and prefrontal cortex play key roles in this vulnerability.
