Why the Teenage Brain Pushes Young People to Ignore Virus Restrictions

Monica Sager didn’t see her boyfriend for four months after she moved back into her childhood home in Pottstown, Pa., in March. She also didn’t go to any friends’ houses or social events.

Now, her parameters have started to shift. Her boyfriend visited from New York over the Fourth of July weekend, and in August she will move into an apartment with roommates in Worcester, Mass., when she returns for her senior year at Clark University.

Ms. Sager, 21, knows that social distancing is key to keeping Covid-19 from spreading....