4.1. Stress-induced modulation of HPA activation on creativity
The current study investigated the role of the HPA axis in the process of acute stress affecting creative performance. Various studies have indicated that activation of the HPA axis under stress results in the release of the glucocorticoid hormone cortisol (Dedovic et al., 2009; Munck et al., 1984). This evidence is consistent with our findings that the salivary cortisol levels of participants increased after the MIST task. The results of the serial mediation analysis showed that the impairment of creativity under stress was mediated by the increase of cortisol concentration and degraded cognitive flexibility.
High cortisol levels have been shown to prevent the coordination between the salience network’s subregions and the central executive network (Hu et al., 2019; Zhang et al, 2019). The salience network is involved in filtering relevant interoceptive and emotional information (Dosenbach et al., 2007; Menon, 2011). The central executive network is engaged in the manipulation of working memory and decision-making (Fox et al., 2006; Knudsen, 2007; Menon & Uddin, 2010). Stress-induced cortisol would enhance the salience monitoring function of the salience network, but the central executive network cannot respond effectively to the control demands launched by the salience network (Hu et al., 2019; Zhang et al., 2022), which is associated with enhanced emotional responses and decreased executive functions (Laredo et al., 2015; Plessow et al., 2011). As is well established, cognitive flexibility – one of the executive functions – is a critical indicator of creativity (Boot et al., 2017). Creative outputs result from two distinct cognitive processes, flexibility and persistence (Nijstad et al., 2010), according to the Dual Pathway to Creativity Model. We predicted that the stress-related HPA axis would therefore adjust the balance between flexibility and persistence to optimize behavior in a changing environment. By this means, stress-induced cortisol elevation enhances perseverative errors, impairs cognitive flexibility and leads to worse creative performance, in line with our results.
Accordingly, cortisol and negative emotions may indirectly influence each other via brain functions. Further studies can employ a cognitive neuroscientific approach to investigate the relationships between different types of negative emotions and cortisol during various types of creative task performance to develop a comprehensive account of the underlying brain mechanisms that are at play.