An emerging research trend has seen concepts from cognitive psychology applied to enhance the creative design process through a more detailed understanding of the underlying cognitive mechanisms. However, the physiological processes by which the human element achieves creative solutions have only recently received significant attention. Understanding the mechanisms that allow the brain to change in response to experience may have implications for creative thought processes. Long-term potentiation (LTP) is one such mechanism, and has already been implicated in learning and memory development. This paper presents a theoretical-physiological explanation of creativity, implicating LTP as a modulator of neural networks. The proposed model is applied to explain existing creativity phenomena, including fixation, incubation, and obstacles in design-by-analogy. The model is then used to describe existing, and propose new methods for overcoming obstacles to creativity in design. The results of a study, which tested one application of the theory — the effect of physical activity on fixation, are also discussed.