276 – Emotional State (Affect) Recognition via Physiological Measures & Processing
This application note is concerned with the implementation details of determining emotional state (“affect”) on the basis of three physiological measures—Electrodermal Activity (EDA, a.k.a GSR), Zygomaticus (EMG), and Corrugator (EMG)s—as suggested in prevailing theories of emotion:
- The James-Lange Theory of Emotion: Emotions occur as a result of physiological reactions to stimuli. Emotional state depends on how the subject interprets their own reaction to any specific event.
- The Cannon-Bard Theory of Emotion: Physiological reaction and emotional state occur simultaneously. Emotions occur when the thalamus activates the CNS in response to stimuli, which results in physiological reaction.
- Schachter-Singer Theory of Emotion: In response to stimuli, a physiological reaction occurs. To experience the reaction and categorize it as a specific emotion, the subject is required to identify the reason for their specific reaction.
Affective states arise from the behavior of two independent neurophysiological systems, the activation (arousal) and valence systems. Affective states are a function of these two systems. The circumplex model is two dimensional, with activation and valence defined as orthogonal (perpendicular) axes.
- The activation axis, plotted vertically, ranges from deactivation (zero arousal) to activation (high arousal).
- The valence axis, plotted horizontally, ranges from negative to positive.