Embracing Uncertainty: Reducing Predictive Precision in Bayesian Inference Enhances Novelty in Creative Design

Creative design is an inquiry process that transforms unknowns into knowns while strategically accepting uncertainty to generate novelty. To understand this computationally, we applied the Inquiry Cycle Model (ICM), which extends the Free Energy Principle by positing that temporary increases in predictive uncertainty maximize long-term information gain. We investigated how modulating this uncertainty influences design ideation by conducting a double-blind, randomized controlled experiment using transcranial alternating current stimulation (tACS). By targeting right temporal alpha oscillations—a neural mechanism for inhibiting obvious semantic associations—we artificially lowered top-down predictive precision during divergent thinking. Results demonstrated that this intervention effectively enhanced self-reported originality in both problem-solving and problem-finding tasks. Crucially, the nature of this creative enhancement was fundamentally modulated by the baseline uncertainty of the task context. In more structured problem-solving scenarios, reducing predictive precision significantly increased objective, corpus-based Bayesian surprise (specifically, maximum information gain and optimal arousal). Conversely, in highly ambiguous problem-finding contexts where prior precision is inherently low, the intervention primarily amplified subjective, internal experiences of insight (aha strength) and confidence. These findings provide causal neurophysiological evidence linking right temporal alpha oscillations to predictive precision. Ultimately, they partially support the ICM and highlight the context-dependent role of predictive precision in fostering novelty during idea generation. This offers a mechanistic account of creative cognition based on the brain’s information-processing principles, laying the groundwork for evidence-based methodologies that deliberately regulate these cognitive states in design practice.