Surviving a traumatic brain injury or stroke can change someone in a lot of ways. So can living with a progressive brain condition like Alzheimer’s disease, multiple sclerosis, or amyotrophic lateral sclerosis (ALS). When you care for someone who has one of these conditions, you might notice changes in their mental abilities as the disease progresses. You may also see noticeable changes in their personality.

People who have a brain injury or neurological disease can also develop sudden uncontrollable and exaggerated emotional outbursts. This condition is called pseudobulbar affect (PBA). If the person you care for suddenly begins to laugh or cry without reason or is unable to stop these emotional outbursts, they have PBA.

Here are seven signs of PBA to look for, and what to do if you think your loved one has this condition.

People with PBA respond to funny or sad situations by laughing or crying, just like anyone else does. But their response is more intense, or it lasts longer than the situation warrants. A humorous scene in a movie can provoke gales of laughter that continue long after everyone else has stopped laughing. Saying goodbye to a friend after lunch might lead to hysterical tears that keep flowing several minutes after the person has left.

In addition to exaggerated responses, someone with PBA may cry when they aren’t sad or laugh when there’s nothing funny going on. Their reaction may have no relationship to the emotion they’re feeling at the time.

With PBA, there may be no connection between the experience at hand and the emotional reaction to it. Someone with the condition may burst into tears at a carnival or laugh out loud at a funeral — two abnormal reactions in such situations.

PBA can pop up suddenly and unexpectedly in almost any type of situation. A person might be completely calm one second, and then suddenly tear up or burst into laughter for no obvious reason.

Most of us have experienced a fit of the giggles in which we couldn’t stop laughing, no matter how hard we tried. People with PBA feel this way whenever they laugh or cry. No matter what they do, they can’t make the emotional outpouring stop.

Emotions can switch from one extreme to the other in PBA. Laughter can quickly turn to tears, and vice versa. The wild swings are due to a problem with the part of the brain that normally regulates emotional responses to situations.

After the laughing or crying has subsided, the person’s emotions go back to normal. The duration of symptoms can help you distinguish PBA from depression. Crying that’s due to PBA lasts a few minutes at a time. With depression, symptoms can last for many weeks or months.

PBA isn’t dangerous, but it can be disruptive to your loved one’s life. Knowing that an emotional outburst is likely can make it embarrassing or uncomfortable for people with this condition to be in social situations.

For this reason, and because PBA can overlap with or mimic depression, it’s important to have your loved one seen by a doctor. The neurologist who treats their condition can diagnose and treat PBA. Or, you might take them to a psychiatrist or neuropsychologist for an evaluation.

A few medicines treat PBA. They include a drug called dextromethorphan hydrobromide and quinidine sulfate (Nuedexta) as well as antidepressants.

Nuedexta is the only drug approved by the Food and Drug Administration (FDA) to treat PBA. However, antidepressants may be prescribed off-label. Off-label drug use is when a drug is used to treat a condition other than the ones it’s received FDA approval to treat.

Nuedexta and antidepressants don’t cure the condition, but they can reduce the intensity and frequency of the emotional outbursts.