With their PASTOR model, Kalisch et al. propose a unified translational model of resilience that can be applied to different disorders. They offer some compelling evidence for this translational model and also some valuable specific suggestions for planned research. Despite their conceptual attractiveness, however, translational models in psychopathology face some difficulties.

Using animal models, or experimental methodologies in general, to study some key higher-order processes (e.g., meaning) or secondary emotions (e.g., shame) can be problematic. An interesting parallel occurred with the learned helplessness model of depression, initially based on animal research. The initial model (Seligman Reference Seligman1975) suggested that unavoidable and unescapable aversive events were sufficient causes of depression. Yet, to extend the model to human depression (which includes specific symptoms such as guilt), the model had to be reformulated by including the attributional style (i.e., the way individuals typically attribute the cause of the event) as the mediating factor between facing an uncontrollable aversive event and the onset of depression (Abramson et al. Reference Abramson, Seligman and Teasdale1978). For example, the search for meaning (Park Reference Park2010) and the reconstruction of shattered core beliefs (Janoff-Bulman Reference Janoff-Bulman1992) are key processes in human appraisal associated with resilience. It is difficult to foresee how these constructs can be adequately manipulated under experimental conditions. Furthermore, these complex processes also bring into sharp relief the fact that (re)appraisal often is associated with lengthy and complicated trajectories that develop over time (Bonanno et al. Reference Bonanno, Westphal and Mancini2011). Also, (re)appraisal is not necessarily focused on the immediate evaluation of a situation, as it is typically studied when using experimental paradigms.

A second challenge for the PASTOR model is related to its definition of resilience. According to Kalisch et al., resilience is an outcome observed when “someone does not develop lasting mental health problems” after having been exposed to adversity. In other words, Kalisch et al.'s approach is anchored on a negative mental health framework (i.e., a view of mental health based on the presence/absence of symptoms). Accordingly, the way they propose to define and measure global resilience (e.g., by psychopathological instruments such as the General Health Questionnaire capitalizes on a restricted view of resilience focused on symptoms.

Yet despite the focus of the PASTOR model on symptoms, recent models of positive mental health emphasize that mental health must be defined not only in terms of symptoms, but also in terms of the presence of capacities, strengths, and well-being (Keyes Reference Keyes2005; Maddux et al. Reference Maddux, Gosselin, Winstead, Maddux and Winstead2012). Any robust model of resilience should seriously integrate the perception of benefits (Helgeson et al. Reference Helgeson, Reynolds and Tomich2006) or even posttraumatic growth (Fredrickson et al., Reference Fredrickson, Tugade, Waugh and Larkin2003; Calhoun & Tedeschi Reference Calhoun and Tedeschi2013) being a frequent experience among those exposed to adversity. Therefore, researchers should attend to the idea that positive dimensions of mental health (e.g., autonomy, self-acceptance, or sense of control; Ryff & Singer Reference Ryff and Singer1998) could be intrinsic aspects of a more comprehensive definition of resilience (Waugh & Koster Reference Waugh and Koster2014).

In terms of the quantification of PASTOR (sect. 3.1), restricting resilience to low presence of symptoms may reduce the variability of the observed data and the predictive power of the model. In other words, it is likely that simply not showing mental health symptoms is not a robust indicator of true resilience (e.g., a reduced vulnerability to develop future psychological crises in facing significant stressors).

Kalisch et al. convincingly state that research on resilience should focus more on mechanisms than on describing factors associated to it, on which there is already an abundant literature. It is easy to agree with the authors in their call for doing research beyond questionnaires and self-reports, thereby overcoming a limitation of research trends in psychology in the last decade (Baumeister et al. Reference Baumeister, Vohs and Funder2007). In terms of mechanisms, Kalisch et al. propose a model that takes into consideration both automatic and controlled processes in the appraisal of aversive situations (sect. 1.3). Although they pay more attention to conscious mechanisms of appraisal (sect. 4.2.5), there are relevant data, from experimental psychopathology, showing that automatic cognitive processes also may play an important role in the appraisal process. For example, using eye-tracking methodologies, Sanchez and Vázquez (Reference Sanchez and Vázquez2014) found that normal, healthy participants pay more attention to happy than sad faces. On the contrary, clinically depressed participants have difficulties disengaging from sad faces (Sanchez et al. Reference Sanchez, Joormann, Marker, LeMoult and Vázquez2013), as well as engaging with happy faces (Duque & Vázquez Reference Duque and Vázquez2015).

Hence, automatic attentional processes do participate in initial stages of appraisal, and what is even more important, they have a significant impact on mood regulation. For example, after the induction of a depressed mood in the laboratory, the more time participants gaze at happy faces, the stronger their recovery from that negative mood (Sanchez et al. Reference Sanchez, Vázquez, Gomez and Joormann2014). Therefore, appraisal/reappraisal mechanisms should be understood within the broader scope of voluntary and automatic emotion-cognition processes.

Finally, also in relation to the cognitive processes involved in positive appraisals leading to resilience, one of the claims of the PASTOR model (sect. 4.2.5) is that positive appraisals are very common in minor or moderate aversive events, but very unlikely in strongly aversive situations. The evidence in the trauma literature does not provide a direct support for this hypothesis, however. It has been shown that a variety of positive emotions can be experienced in the immediate aftermath of stressful events such as a devastating earthquake (Vázquez et al. Reference Vázquez, Cervellón, Pérez-Sales, Vidales and Gaborit2005), a massive terrorist attack (Vázquez & Hervas Reference Vázquez and Hervás2010), or in the first 72 hours after a myocardial infarction (Castilla & Vázquez Reference Castilla and Vázquez2011). These findings reveal that even in highly aversive situations, positive appraisal processes may be more common than expected, and also that they may emerge during the events (Vázquez et al. Reference Vázquez, Pérez-Sales, Hervás, Joseph and Linley2008).

In conclusion, the PASTOR model makes a valuable effort to create a framework to establish consistent bridges between animal and human research. Yet, human responses to adversity can be very complex, often including higher-order psychological constructs (e.g., reconstruction of shattered beliefs) as well as outcomes that go beyond resilience (e.g., psychological growth). A sound model of resilience should consider these intrinsic ingredients of human response to life adversities.