University researchers have conducted a study which has found that people actually have physical reactions to music that is both emotional and meaningful to them, shown in the dilation of their eyes, according to the Daily Mail.
The University of Vienna was involved in a study that found that a person’s personal attachment to music, matched with the “emotional content” of the music caused their eyes to dilate.
Researchers took about 80 piano excerpts from the romantic era and had them rated based on how emotional they were by 30 people.
Then they took 30 other participants, blind to the true purpose of the study, and allowed them to listen to the music while their pupils were measured by an eye tracker.
After they completed the listening, they filled out a survey about how much music means to them. Those that had a stronger relationship with music in their lives saw larger dilatation.
The pupil reflexively changes its size to adjust to ambient light, contracting in bright daylight and dilating at night. However, pupil size can also be affected by “thoughts, emotions, or mental effort,” according to the press release. “Sounds may also evoke pupil dilations, depending on their emotional content.”