Meagan Longoria explains the concept of cognitive load and how it relates to building reports:
Our first design concept is cognitive load, which comes from cognitive psychology and instructional design. Cognitive Load Theory says that when we present our audience with information, we are asking them to use brain power to process it. That brain power (aka working memory) is limited, so we need to be intentional about the information we present to them.
In order to commit information to memory and be able to recall it later, that information must go through sensory memory and working memory and then be encoded into long-term memory.
This concept drives a lot of good advice in dashboard and report design, particularly that if it does not directly help a person learn the important information you are trying to convey, it’s not worth having on the report or dashboard.