Even under similar circumstances, people often experience and express their emotions very differently. Emotion is made up of three distinct components: a subjective experience, a physiological response, and an expressive response.
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In this program, students learn about the origin of human emotion from the evolutionary perspective, the physiological mechanisms involved in emotions, and some of the latest research findings on the subject.
Charles Darwin, one of the earliest scientists to study emotion, argued that all organisms show emotion through similar behavioral expressions. He believed that emotions had an evolutionary quality that contributed to survival and reproduction by communicating information about an individual's internal state to one another. Darwin's conclusion that emotions were universal across cultures was later adopted and proven by researchers to have statistical significance.
Evidence suggests that six basic emotions exist in all human cultures: happiness, fear, sadness, anger, surprise, and disgust. Emotions, as Daniel Gilbert points out, can be located in a two-dimensional space: valence and arousal. The dimension of valence ranges from positive to negative, and the dimension of arousal ranges from active to passive. The fact that these emotional dimensions and expressions are universal suggests that they hold evolutionary value. The complexity with which we can express emotion is matched by the skill we have in decoding these expressions, making this an adaptive response.
The nervous system, specifically the sympathetic branch of the autonomic nervous system, is aroused during highly emotional states. In a fearful state, for example, the nervous system triggers the fight-or-flight response, cueing the body to release hormones, move blood to organs and muscles, and preserve energy from other system functions. The amygdala shows heightened activity when we are exposed to stimuli that evoke fear, which is connected to our limbic system, a system we share with other animals. Different brain areas are associated with different emotions.
Although emotions are very much rooted in our biology, our environment provides consequences for emotional behavior, which ultimately influences how we use and feel about our emotions.