In this study, we tested whether the visual complexity (VC) of webpages influences viewer's affective reactions. In a laboratory experiment, 48 students viewed 36 webpages varying in VC while subjective feelings, behavioral, and cardiovascular responses were recorded. Less complex webpages were associated with more positive affect, decreased eye movements (specifically in the first few seconds of viewing), a triphasic heart rate response, and increased finger pulse amplitude. Results suggest that affective responses to webpage viewing differ as a function of VC and that webpage displaying could be made adaptive to the user's emotions.

Emotions powerfully influence our physiology, behavior, and experience. A comprehensive assessment of affective states in health and disease would include responses from each of these domains in real life. Since no single physiologic parameter can index emotional states unambiguously, a broad assessment of physiologic responses is desirable. We present a recently developed system, the LifeShirt, which allows reliable ambulatory monitoring of a wide variety of cardiovascular, respiratory, metabolic, motor-behavioral, and experiential responses. The system consists of a garment with embedded inductive plethysmography and other sensors for physiologic data recording and a handheld computer for input of experiential data via touch screen. Parameters are extracted offline using sophisticated analysis and display software. The device is currently used in clinical studies and to monitor effects of physical and emotional stress in naturalistic settings. Further development of signal processing and pattern recognition algorithms will enhance computerized identification of type and extent of physical and emotional activation.