Summary
Highlights
For many years, researchers debated the best definition of emotion. Modern understanding recognizes emotion as a process involving an interplay of various responses, initiated by an antecedent event that triggers an emotion.
Antecedent events are stimuli that provoke emotions. These events lead to an appraisal, where we interpret and make sense of the encountered situation. The appraisal then dictates the emotional response.
Emotional responses are categorized into physiological changes (body's internal reactions), behavioral expressive changes (observable actions like facial expressions), and subjective changes (internal feelings). Each type serves a distinct function in dealing with emotional situations.
Physiological changes are mainly controlled by the autonomic nervous system, comprising the sympathetic (fight-or-flight) and parasympathetic (rest-and-digest) divisions. Fight-or-flight responses, like a racing heart, activate during intense emotions, while rest-and-digest responses occur during relaxation. These responses are involuntary.
Behavioral expressive changes involve observable body movements, with facial expressions being the most prominent in humans. The Facial Action Coding System (FACS) categorizes these movements, revealing that certain muscle combinations are universally interpreted as specific emotions. Genuine (Duchenne) smiles, for instance, involve both mouth and eye muscles. We have more conscious control over these responses than physiological ones.
Subjective changes are personal internal responses, or 'feelings.' Each emotion produces a unique feeling. While both fear and anger can increase heart rate, their subjective experiences differ. These feelings are typically measured through self-reports, limiting their study to individuals with verbal ability.
Measuring emotional responses requires a diverse toolkit. Physiological changes are detected by measuring autonomic nervous system functions like heart rate (e.g., in polygraphs). Behavioral responses are observed, with facial expressions being the easiest to detect in humans, though they can be consciously controlled. Subjective feelings are measured via self-reports, making it challenging to assess emotions in non-verbal individuals.