KEYRIS MANZANARES: Dr. Laura Wilson, an associate professor of psychology at the University of Mary Washington, says that people's reactions after a mass shooting are as unique as they are.

LAURA WILSON: We find that a lot of people are actually surprisingly resilient.

Some people experience very little fluctuation in their functioning.

KEYRIS MANZANARES: But people who are physically injured often have more long-term mental health issues.

LAURA WILSON: It's fairly typical for someone who has been directly impacted to have at a minimum, short-term issues.

That could be difficulty sleeping.

They might have some survivor guilt.

They might also have some anger and some frustration, depending on the nature of the shooting, but then that can also translate into long-term issues like depression and PTSD.

KEYRIS MANZANARES: When it comes to workplace mass shootings like we saw at the Chesapeake Walmart, Dr. Wilson says survivors tend to feel more survivor's guilt.

LAURA WILSON: A survivor might say, "I knew this person and I maybe could've done something.

I maybe could've predicted this was going to occur."

Sometimes, it might lead to more anger, because maybe, they feel like the place of employment could have stopped it.

KEYRIS MANZANARES: The community also feels an impact, because of the news they see about mass shootings on social media.

LAURA WILSON: We see that a lot of individuals are live streaming events.

They're tweeting as things are happening.

They're texting family members.

There's more video footage than ever before of people hiding or fighting back during mass shootings and it's giving people a front row seat to the horror.