#18401
Emotion & Design: Attractive Things Work Better 
Advances in our understanding of emotion and affect have implications for the science of design. Affect changes the operating parameters of cognition: positive affect enhances creative, breadth-first thinking whereas negative affect focuses cognition, enhancing depth-first processing and minimizing distractions. Therefore, it is essential that products designed for use under stress follow good human-centered design, for stress makes people less able to cope with difficulties and less flexible in their approach to problem solving. Positive affect makes people more tolerant of minor difficulties and more flexible and creative in finding solutions. Products designed for more relaxed, pleasant occasions can enhance their usability through pleasant, aesthetic design. Aesthetics matter: attractive things work better.
Norman, Donald A. JND.org (2002). Design>Web Design>Usability>Emotions
#33719
Beyond Usability: Designing Web Sites for Persuasion, Emotion, and Trust
The next wave in Web site design is persuasive design, designing for persuasion, emotion, and trust. While usability is still a fundamental requirement for effective Web site design, it is no longer enough to design sites that are simply easy to navigate and understand so users can complete transactions. As business mandates for Web site design have grown more strategic, complex, and demanding of accountability, good usability has become the price of competitive entry. So, while usability is important, it is no longer the key differentiator it once was.
Schaffer, Eric M. UXmatters (2009). Articles>Web Design>Usability>Emotions
