The aim of this research is to contribute to the body of knowledge on mental models in the fields of design methodology, engineering psychology and human factors by studying the resistance of mental models to change. In this work the term cognitive resistance is introduced as the capacity to endure stimuli from the environment that contradict the mental model, and its episodic nature is investigated. Three main points have been addressed in the current research: the identification of the components of cognitive resistance, an investigation into their interaction, and the identification of environmental and intra-subject factors that influence cognitive resistance. These issues are investigated from a theoretical and from an experimental perspective.