Building on prior theory on positive psychological change, including the Hedonic Adaptation Model
(Sheldon, Boehm, and Lyubomirsky, 2013), the Positive-Activity Model
(Layous and Lyubomirsky, 2013), and the emotion regulation theory
(Quoidbach, Mikolajczak, and Gross, 2015), the Synergistic Change Model (SCM) emphasises the interplay of many dynamic elements that facilitate successful and sustained positive change. The model is based in complex dynamics systems theory (Thelen, 2005); recognising that psychological change is a fundamentally complex process and involves interaction between many dynamic elements. It also centres upon on the' Domains of Positive Functioning' (DPF-5) framework
(Rusk and Waters, 2014), which emphasises five domains of psycho-social functioning, including: attention and awareness, comprehension and coping, emotions, goals and habits, and relationships and virtues. The influence of environmental and biological/physiological factors are also recognised (Rickard & Vella-Brodrick, 2014), although not characterised. The SCM suggests that whilst each of the psycho-social domains operate independently (Rusk & Waters, 2015), each element may also interact and influence functioning in all other domains; working to either reinforce or undermine change. Crucially, it is this dynamic interdependence between domains which is fundamental to lasting positive change in functioning.
According to the SCM, interventions may result in one of three processes of change: relapse, spill-over, and synergy. ‘Relapse’ may occur when changes in one domain are inadequate, unstable, and made to one of two domains in isolation. Isolated changes are less likely to change the overall dynamic stability of the psycho-social system and instead results in between-domain interactions which undermine and prohibit initiated change within a given domain. Thus, individuals revert to their original state of undesired functioning. In contrast, spill-over occurs when the effects of positive change in one domain "spill over" to enhance functioning in other domains. Spill over effects from enhancements in one domain on to another are often reported in qualitative investigations of patient experiences (Landsman-Dijkstra, van Wijck, & Groothoff, 2006) and may be evidenced as mediation effects within the literature (Toussaint & Friedman, 2009). Spill-over effects demonstrate that cognitive functions do not operate independently and offer insight as to how different interventions may result in similar changes being accomplished through multiple pathways of pursuit (Oman, Richards, Hedberg, & Thoresen, 2008). However, these residual effects are often temporary and offer no promise of sustainable change. To successfully induce stable and enduring change, mutually supportive and reinforcing changes must occur within several domains of psycho-social functioning. This insight comprises synergy and results in a new dynamically stable pattern of behaviour. These synergistic interactions have been typically referred to as upward positive spirals within the PP literature (Ryff & Singer, 1998; Crawford & Caltabiano, 2011; Gudan, 2010; Lyubomirsky & Layous, 2013; Wood, Maltby, Gillett, Linley, & Joseph, 2008) and identified as mechanisms through which PPI’s may enhance well-being (Cohn & Fredrickson, 2010). According to the SCM, the formation of these synergistic spirals is a powerful means by which the effect of a PPI can be made enduring; and that PPI’s will be more effective if they are designed to produce synergistic change.
Considering features central to sustained positive change, Rusk et al., (2017) highlight several strategies that can be adopted to facilitate interventions; including targeting pivotal domains, leveraging existing strength’s and values, and targeting mutually reinforcing elements. Briefly, pivotal elements are those domains that can initiate synergistic changes that ‘tip the system into a new stable mode of functioning’ (Rusk et al., 2017). For example, positive emotions are considered pivotal elements that create ‘upward spirals’ that broaden thought-action repertoires, build psychological and social resources and foster positive emotions futher (Fredrickson & Joiner, 2002; Fredrickson, 2004; Garland et al., 2010). Consequently, PPIs that cultivate positive emotions may trigger synergistic changes within a range of psycho-social domains that enhance and sustain benefits to well-being. Further to this, intervention strategies should be tailored to an individual’s traits, values or character strength’s profile; leveraging these to support the desired change through synergistic interactions. Lastly, the SCM (Rusk et al., 2017) suggests that change within a given domain of psycho-social functioning, particularly non-pivotal domains that lack synergistic potency, will be more successful if mutually reinforcing domains are targeted to foster synergistic change and stabilise functioning. Moreover, the SCM suggests that targeting elements of psycho-social functioning from the behaviour change literature (e.g. implementation intentions, self-efficacy) in addition to elements from the PP literature (e.g. gratitude, optimism, or mindfulness) may further induce enduring change. Thus, the SCM holds the potential to integrate the knowledge captured within existing behavioural change theories to bear in creating positive psychological change.
INTEGRATE THIS: Interventions aimed at increasing positive emotion facilitate the building of social connections. For instance, training in loving-kindness meditation \citep{Kok_2010,Kok2015,Kok2013} elicits positive emotion and this is dependent (moderated by) baseline vagal tone. Increases in positive emotion lead to subsequent increases in vagal tone, mediated by an increase in the perception of social connectedness. Higher vagal tone predicts greater social engagement at follow-up, and higher social engagement due to the intervention predicts further increases in vagal tone \citep*{Kok_2010}. These findings highlight a self-sustaining upward spiral between vagal function, emotion and social connections. Acute nasal administration of oxytocin may be another method to trigger cycles to improve health and wellbeing as it increases capacity for social engagement (Kemp et al., 2012). Conversely, decreased vagal activation results in increased sympathetic activity, associated with the fight-flight-or-freeze responses, which causes withdrawal behaviours (e.g. anxiety) not conducive with social environments (Porges, 2011)
Theories, as conceptualised here, ranged from quite specific (e.g., to a particular behavioural domain or type of intervention) to very general, including multiple levels of influence. The cut-offs at either end of this spectrum were agreed by consensus but were inevitably arbitrary. A general observation was that more general theories may have greater face validity but be less useable in guiding research than more specific theories; choice of theory will therefore be partly guided by the purpose it is to be put to. Another observation was that there appeared to be no generally accepted use of terms such as theory, model, framework and orientation, with different uses by different authors. Increasing the precision of, and consensus on, use of terminology would be helpful for the field.