Answer: In the original misattribution of arousal studies, psychology researchers found that people confused the physical symptoms of anxiety or fear with romantic love.
When we are anxious or experiencing fear, our bodies inherently react with a series of physiological changes. These changes include an increase in heart rate, a dilation of pupils, more rapid breathing, increased blood flow to the muscles, and elevated blood pressure. Collective, these changes are called the sympathetic nervous system response. On a short term scale (seconds to minutes), these changes are adaptive and help the body prepare for facing dangerous threats in the environment.
The sympathetic response is believed to be an evolutionary holdover from the proto-human days. In facing a life or death situation, an early humanid would have to decide whether it was in their best interest to fight the predator, or to run away. Either of those responses requires an increase in delivery of oxygen to the muscles, which is downstream of the sympathetic response. Therefore, the person would become better adapted for survival if their body responded to dear full stimuli in this manner.
The sympathetic nervous system is driven by a neurotransmitter called norepinephrine. When the brain perceives a threat, norepinephrine release is signaled at the level of the sympathetic ganglia, which are two paired “chains” of neurons that run alongside the spinal cord. These neurons produce norepinephrine and release it directly into the bloodstream, where it can then be distributed across the entire body to reach several organs and affect their activity.
These same sympathetic responses are very similar to the physical manifestation and symptoms of when a person is in love (dilated pupils, elevated heart rate and respiration, increase in blood pressure, etc.) The idea of misattribution of arousal states that when a person experiences the sympathetic nervous system response, their brains are unsure if they are feeling those physiological changes due to romantic emotions or stress, anxiety, or fear.
Dutton and Aron, 1974: Bridge Study
The original study that demonstrated misattribution of arousal was performed by two psychologists in 1974, Donald Dutton and Arthur Aron. They published the results in the Journal of Personality and Social Psychology. The article is called SOME EVIDENCE FOR HEIGHTENED SEXUAL ATTRACTION UNDER CONDITIONS OF HIGH ANXIETY. In the experimental paradigm, their subjects crossed one of two bridges: a scary suspension bridge that was several feet off the ground, or a significantly more secure bridge closer to the ground. The suspension bridge elicited fearful responses, since the bridge was high off the ground, while the control bridge served as a control condition that did not elicit fear.
A female researcher was placed halfway across the bridge, and would stop the subjects as they crossed the bridge. At this point, the female experimenter would ask the subjects to complete a Thematic Apperception Test. In the Thematic Apperception Test, the subject would be shown an intentionally ambiguous image, such as a picture of a woman covering her face and laughing. The subject was asked to write a background story that explained the reason for the image. The subjects were told that the study was meant to assess the effects of beautiful scenery on a person’s creativity. The content of the story was then scored by the experimenter, searching for content that was either sexual or romantic in nature. In their scoring paradigm, stories were rated from 1 to 5, with a 1 containing no romantic content whatsoever. A 2 might contain the word girlfriend or fiance, a 3 might contain the word kiss, and a 4 would contain the word lover, for example. A 5 was given if there was any content related to sexual intercourse.
Additionally, the female experimenter would give her phone number to the subjects and ask them to call her if they wanted to learn more about the nature or purpose of the experiment.
To serve as a further control group, they repeated the experiments with a male experimenter asking the same questions of male subjects crossing the bridge. The interviewers were not told of the intent behind the experiment. This way, it decreases the likelihood that the interviewer would engage in unusually flirty behavior.
Results from Dutton and Aron’s bridge study
Dutton and Aron hypothesized that subjects would confuse the fear they experienced as they crossed the bridge with sexual arousal that they experienced on seeing the woman. If the subjects did display a misattribution of arousal, then it could be expected that the content of the story would contain more romantic or sexual imagery if they crossed the fear-inducing bridge compared to the safe control bridge. The subjects who crossed the fear-inducing suspension bridge wrote background stories such as “The woman was embarrassed because her boyfriend just proposed to her”. On the other hand, the control subjects wrote generic back stories with no romantic content at all, such as “she is laughing about something unimportant.”
The percentage of people who called the female experimenter later was also calculated. Around 20% of control bridge male subjects ended up calling the woman later, whereas half (9 out of 18) of the experimental bridge subjects called. In the male-interviewer control group, most who took the experimenter’s numbers did not call: only 2 out of 23 in the experimental group called, and only 1 out of the 22 in the control group called.
According to Dutton and Aron’s interpretation, this meant that the subjects misattributed their body's fear response to the physiological effects of experiencing romantic love.
Dutton and Aron’s Shock Anxiety study
The two researchers demonstrated that misattribution of arousal was present in the subjects who crossed the fear-inducing suspension bridge. They were also curious to see if anxiety over some future event would be sufficient to induce a similar misattribution of arousal. They theorized that fear and anxiety are very closely related. Both stimuli produce the same set of physiological responses that is seen in romantic love and attraction: elevated heart rate and respiration, rapid breathing, and dilation of pupils, for example.
For this experiment, they recruited subjects who were put into a room with a confederate who was acting as another test subject. For the experimental group, the confederate was of the opposite gender, while in the control group, they were of the same gender. From here, they were told that they soon receive an electric shock at one of two different intensities. They were told that the low intensity shock would be a mild tingle, and that some even find that stimulus pleasurable. The other electric shock was supposed to be painful. Which shock they received would be decided by a coin flip. The subjects would then would be told that they will receive the painful stimulus. In order to increase the anxiety level of the subjects, the experimenter spent some time describing the physical setup of the experiment. For example, the subjects were told explicitly how they were to be connected into the electrodes, and how the shock will be delivered.
After this, the subject was given a survey to report their feelings about the experiment. First, they were asked how anxious they were about receiving the shock on a scale from 1 to 5, with 3 being neutral. Then, they were asked to rate the attractiveness of the other “subject,” asking questions such as “How much would you like to ask her out on a date?” and “How much would you like to kiss her?”
Results from the shock anxiety study
Dutton and Aron found that there was an elevated level of attraction to the other person from the subjects who were anticipating a strong electrical shock and higher self-reported anxiety over the shock compared to those who were anticipating a low intensity shock. The experimenters concluded that anxiety related stimuli that trigger a physiological sympathetic nervous system response may be confused for the same physiological response that occurs during sexual attraction or lust.