The paper, by Ronald Bledow, Kathrin Rosing and Michael Frese, does not contest the idea that positive emotions crucially support creativity: what they propose is that positivity rising over time while negativity descends over time may offer better conditions than high positivity coupled with an absence of negative affect. They provide two reasons for this.
Firstly, the narrow, alert focus on issues can be useful by focusing on things that are in need of a solution and spurring motivation to act on these; previous research does suggest that negative emotion can lead to more persistence in problem solving. Once this focus has been set, allowing the negative emotions to slide away and positive emotions to explore the possibility space is a good recipe for getting to innovative solutions. The first study investigated this by asking 102 participants in creative roles to document their affect at the start and end of each day for a week, independently rating positive (excited, alert, inspired) and negative (distressed, hostile, guilty) emotional terms. Positive affect at the end of the day predicted how much creativity the participant reported in that day, but that relationship was significantly stronger when start-of-day negative affect was higher.
In a second, experimental study, Bledow's team focused solely on another advantage of starting in a negative mood, that it is specifically a decrease in negative mood that opens up associative networks of memory, allowing wider associations. The 80 participants in this study completed a brainstorming task after writing an autobiographical essay about a positive event. Before either, all participants wrote an initial autobiographical essay, and those who were tasked with articulating an unpleasant instead of a neutral experience ultimately performed better the brainstorming task, producing more varied and unique ideas. This happened even though the negative state had no function in focusing their attention on anything related to the creative task, which suggests the better performance was due to entering a more suitable cognitive mode.
Further research is needed on these dynamic relationships between different types of affect, in particular to examine more closely how fluctuations on a shorter timescale may impact work goals. But this paper suggests that treating positive affect as the wellspring of creativity may perversely be itself an example of overly narrow focus. Individuals who routinely dismiss negative thoughts to stay in their happy place may wish to dwell a little longer, as a station on the way to their creative destinations.
Baas, M., De Dreu, C. K. W., & Nijstad, B. A. 2008. A meta-analysis of 25 years of mood-creativity research: Hedonic tone, activation, or regulatory focus? Psychological Bulletin, 134: 779 – 806.