Blunted reward-related VS reactivity indirectly conferred risk for non-anhedonic depressive symptoms through stress-related anhedonia. This finding is congruent with prior epidemiologic work indicating that depression is frequently preceded by ELS (Monroe & Hadjiyannakis, 2002; Heim et al. 2008; Heim, 2009; Heim & Binder, 2012) and research linking major depressive disorder to blunted striatum reactivity to reward (Epstein, 2006; Steele et al. 2007; McCabe et al. 2009). Evidence suggesting that anhedonia precedes the development of depression (Dryman & Eaton, 1991) and that hedonic impairments can be induced by stress (Pizzagalli, 2014) provide further support for this model. Moreover, recent evidence demonstrating that self-reported positive, but not negative, emotion regulation prospectively predicts later depression symptoms in those exposed to high levels of stress (Bijttebier et al. 2012) highlights the key role of reward pathways in stress-related psychopathology.
