Final answer:
Emotion always involves a complex reaction to stimuli, including cognitive appraisal and physiological responses, as supported by various theories such as James-Lange, Cannon-Bard, and Schachter-Singer.
Step-by-step explanation:
Emotion always involves a complex reaction to stimuli, which is a subjective experience that triggers cognitive appraisal, expression, and physiological responses. This process can be internal, such as when a thought provokes an emotional response without an external trigger. The James-Lange theory proposes that we first experience physiological arousal and then identify the emotion, while the Cannon-Bard theory suggests that the arousal and emotional experience occur simultaneously. The Schachter-Singer two-factor theory indicates that physiological arousal and cognitive appraisal work together to produce an emotional experience. This concept is further advanced by Damasio's explanation of homeostasis and the feedback loop involving neurotransmitters, and by LeDoux's research showing that some emotional responses can bypass cognitive assessment.