You're the first student to give their presentation in Spanish class. It's a fairly long speech, and the whole thing has to be in Spanish. Your mouth is dry and your heart thumps too fast, but you finish it. As everyone applauds, you look up and make eye contact with your crush. They're smiling and clapping, and you can feel your heart racing. As you take your seat, you decide you were really nervous about making a good impression on your crush rather than your teacher. You duck your head as the next speech begins, hoping no one notices you're blushing.
If someone had stopped you mid-speech and asked how you were feeling, you likely would've said you were scared, not lovesick. After all, it's the fear of presenting that first hastens your heartbeat. Yet once you decide through environmental cues that your crush caused your reactions, all other explanations fall away. Your emotions then are not only made up of physiological arousals - like your beating heart and dry throat - but the cognitive labels you give them - like pre-presentation jitters or lovey-dovey butterflies.
The Two-Factor Theory of emotion states that emotion is experienced in a combination consisting of exposure to stimuli, physiological arousal, cognitively labeling the emotion, and just overall experiencing the emotion. Stanley Schachter and Jerome E. Singer coined the theory and decided to test it in 1962 in what would later be known as the Schachter and Singer Experiment.
The Schacter and Singer Experiment was conducted at Columbia University with 184 male subjects. Participants were split into four different groups and told that they'd be injected with a vitamin before having their eyesight tested. In reality, three of the test groups were injected with epinephrine, or adrenaline. Depending on which group they were in, subjects were informed of the correct side effects they'd experience (like an increased heart rate), misinformed about what symptoms to expect (like itching and headaches), or not informed of potential side effects at all. Members of the fourth group, the control, were instead injected with a placebo and not informed of potential side effects.
Next, participants were placed in two separate rooms and told to wait with fellow participants. In reality, the other participants were confederates of the experiment. In one room, the confederate would act angry, while in the second room, the confederate would act euphoric and happy. The key to this experiment was seeing how participants would respond.
Schachter and Singer found that participants uninformed about the injection's true side effects felt either happier or angrier compared to informed participants. Since participants didn't know the injection would affect their physiological arousal, they interpreted such reactions based on their confederate's mood. If their confederate was angry, they themselves became angry, and similarly, if their confederate behaved euphorically, they themselves became happy.
The experiment showed that people rely on their environmental cues to explain how they're feeling. All experimental groups had the same physiological responses to their injections and relied on available data to explain them. Informed participants could match their reactions to the side effects they were told of and thus didn't experience any heightened emotions. Uninformed participants did not have that knowledge and therefore relied on their confederates' reactions. The divide of emotional response between informed and uninformed participants shows that cognitive labeling does play a significant role in our feelings.
Replications of the original experiment have produced inconsistent results. One study found that participants experienced negative emotions regardless of their confederate's apparent emotional state. Most studies didn't witness significant emotional changes, partly because of difficulty replicating this experiment. Also, a major criticism is that not everyone experiences emotions in sequential order. At times, there is so much sensory overload that it is not realistic for people to pause and label what they're experiencing—they simply feel it, perhaps cognitively identifying their emotions in the aftermath.
Everyone experiences emotions differently, and they're influenced by many factors, such as their prior knowledge, awareness, and surroundings. If you don't experience anger or euphoria the same way as the next person, that's completely normal. Maybe you have a higher inclination to process feelings in the moment, or perhaps you tend to be very aware of complicating factors that could be affecting your mood. If there's one thing the Schacter and Singer Experiment proved, it's that emotions aren't as simple as we make them out to be.