“Because the train was not fully inside the station it took a while to discharge customers off the train,” he said.

A couple of hours after the transit agency announced that the situation had been resolved, L train service was disrupted once again, this time by signal problems.

Because official explanations about how small problems, like a faulty door, can lead to big headaches often fail to satisfy riders, each subway meltdown elicits a corresponding flood of tweets, Snaps, Facebook and Instagram posts meant to share commuters’ misery with the world.

Whether it makes people feel better to post their frustrations on social media is an open question and something of a charged topic of scholarly investigation.

There is a reason the expression misery loves company is a cliché.

When it comes to direct person-to-person contact, emotional contagion can lead people to experience the same emotions without being aware they are doing so.

Social media — where contact is less direct — is different and psychiatrists and social scientists are still trying to understand its impact.

A study in an academic journal “The Proceedings of the National Academy of Sciences,” which was published three years ago and remains controversial, found that when positive content was reduced in users’ Facebook news feeds, a larger percentage of words in their status updates were negative and a smaller percentage were positive. When negativity was reduced, the opposite occurred.