UX Design Guided by Cognitive Load Theory
Nadine Marcus, Alexandra Vassar · 2025
Jacob Nielsen has provided a list of 10 general principles for Interaction Design that are widely employed by UX (user experience) designers. These heuristic design principles serve to support the design of more usable interfaces. Cognitive load theory, which focuses on scientifically based empirical approaches to designing instructions and interfaces that minimise the burden on our limited capacity to process new or unfamiliar information, underpins the effectiveness of these principles. Using these principles in design therefore helps to guide the design in such a way that users can focus on the goals of the task at hand, rather than being distracted by the extraneous load of interacting with a poorly designed interface. Cognitive load theory posits that we have a limited working memory responsible for processing new information and a vast store of familiar information stored within our long-term memories. Working memory, often referred to as our consciousness, is constrained both in terms of the amount of new information it can process at a time, as well as the time this information can remain in our consciousness. We can overcome some of these processing limitations by relying on our vast stores of prior knowledge stored in our long-term memories. By designing interfaces that aim to reduce constraints on our limited working memories and rather tap into resources stored in long-term memory, users will benefit from these design principles. This chapter aims to theoretically ground each of Nielsen’s heuristics within cognitive load theory principles, explaining why the practical guidelines are so effective in improving interface design. We will also provide an overview of relevant empirically validated cognitive load effects. Establishing this connection between the theory and the usability guidelines can help users of the heuristics better understand why they work and enable designers to more broadly and intuitively implement good design practices. It should be noted that while heuristic design principles and evaluation are a useful tool in the early stages of the interaction design lifecycle, they should not replace thorough usability testing later in the design lifecycle.