Visual complexity of websites: Effects on users’ experience, physiology, performance, and memory

Visual complexity is an apparent feature in website design yet its effects on cognitive and emotional processing are not well understood. The current study examined website complexity within the framework of aesthetic theory and psychophysiological research on cognition and emotion. We hypothesized that increasing the complexity of websites would have a detrimental cognitive and emotional impact on users. In a passive viewing task (PVT) 36 website screenshots differing in their degree of complexity (operationalized by JPEG file size; correlation with complexity ratings in a preliminary study r = .80 ) were presented to 48 participants in randomized order. Additionally, a standardized visual search task (VST) assessing reaction times, and a one-week-delayed recognition task on these websites were conducted and participants rated all websites for arousal and valence. Psychophysiological responses were assessed during the PVT and VST. Visual complexity was related to increased experienced arousal, more negative valence appraisal, decreased heart rate, and increased facial muscle tension (musculus corrugator). Visual complexity resulted in increased reaction times in the VST and decreased recognition rates. Reaction times in the VST were related to increases in heart rate and electrodermal activity. These findings demonstrate that visual complexity of websites has multiple effects on human cognition and emotion, including experienced pleasure and arousal, facial expression, autonomic nervous system activation, task performance, and memory. It should thus be considered an important factor in website design.