When our information representations have emotional content, it is useful to have studied what little is known about human emotions from an engineering point of view. I am not suggesting that designers should study the neurophysiology of the brain. While such studies can lead to useful knowledge about how people absorb and react to representations of information, how the brain functions internally is not directly relevant to our field. We can treat the brain as a black box and safely ignore all the twaddle about the parts of the brain and what they do. I think not.
Useful information takes an operational form.
Every major field of human endeavor is a mix of art and science. Theoretical physicists and professional mathematicians speak of the aesthetics of their work, and are driven by concerns about elegance and beauty. Designing the presentation of information, by the same token, partakes of the nature of both art and science. Edward Tufte's books reflect such a blend of knowledge. Describing electronic displays in terms of numbers of pixels no more makes our work technical than the fact that the frequencies of consecutive notes of the tempered chromatic scale have a ratio of the twelfth root of two makes musical composition a hard science.