Yes, pupils dilate when talking to someone you like. The pupils dilate when we see something stimulating or when we are in low light area. The brain is responsible for the change in the size of the pupils when one is attracted to another person.
Other conditions that cause dilation of pupils are fear, anxiety, flight and fight response. The sympathetic nervous system is stimulated and signals are sent to the pupils to dilate them.
Yes, your eyes can dilate (or widen) when you are attracted to someone. This is believed to happen because your body’s central nervous system can cause a number of different effects on the body, including the eyes. Your pupils can also dilate in response to other strong emotions such as hate or fear. Researchers are studying the dilation process in the hopes of better understanding psychological disorders.
There are other reasons that can cause eye dilation, for example, legal and illegal drugs, and poisons can cause pupils to dilate. Again, because your eyes are connected to the central nervous system, an injury to the brain can also cause eye dilation.