A fascinating new link between breathing and the size of our pupils, the black circles in the center of our eyes, has been discovered. This new finding shows that pupils are smallest when we start to breathe in (inhalation) and largest when we breathe out (exhalation).

For a long time, it was believed that pupils were largest when we breathe in and smallest when we breathe out. However, a recent set of experiments conducted by researchers has shown a different pattern, known as the "Respiratory-Pupillary Phase Effect" or RPPE.

In the experiments, participants were asked to breathe normally while resting and doing visual tasks. Their breathing and the size of their pupils were measured. It was found that regardless of whether participants were breathing through their nose or mouth, their pupils always became smallest when they began to inhale and largest when they exhaled. On average, pupil size increased by about 7% from the start of inhalation to peak exhalation.

This discovery is important because it challenges the old idea and shows that pupil size changes in sync with the breathing cycle. Understanding this link could provide more insight into how the brain and body work together, particularly in how we respond to different tasks and environments.

p>The findings open up new possibilities for studying how breathing affects brain function and behavior. Future research could explore the mechanisms behind this effect and its influence on visual perception and cognitive functions.