Fostering better creativity in design education: Exploring the “sweet spot” effect in mood board constraints

Modern design education requires innovative approaches to inspire and enhance creativity. Prior research suggests that cognitive stimulation levels significantly influence creative performance, with an optimal level known as the “sweet spot” effect. However, studies specifically addressing inexperienced designers remain limited. While mood boards are commonly used as visual stimuli in design processes, few studies, particularly in educational contexts, have explored the optimal level of stimulation. This gap may stem from challenges such as novice users’ limited expertise and the absence of refined instructional strategies. This controlled experiment aimed to explore whether an optimal level of stimulation exists in mood board design activities. Participants were classified into low-, moderate-, and high-constraint groups based on the degree of image involvement. The study employed the sweet spot framework, treating creativity level as the dependent variable and constraint level as the independent variable. Creativity in design sketches was evaluated across four dimensions: novelty, variety, quality, and quantity. Mood board effectiveness was subjectively assessed using three criteria: innovation, consistency, and visual attractiveness. The results indicated that the moderate-constraint group proved most effective in stimulating creativity across these four metrics. They also required less creation time than the high-constraint group. Moreover, moderately constrained mood boards demonstrated the largest number of significant positive correlations with sketch creativity. Furthermore, the study identified the characteristics of mood boards with low and high constraint levels. Based on these findings, this study proposes practical instructional strategies to foster creative education using mood boards.