Condition Basics

What is pseudobulbar affect (PBA)?

Pseudobulbar affect (PBA) is a problem in the brain that causes you to laugh or cry for no reason. The sudden fits of tears or laughter usually have nothing to do with what you're feeling. And you can't control them. Living with PBA can be very stressful.

What causes it?

Brain damage from a stroke, brain tumour, or head trauma can lead to PBA. PBA can also happen along with such conditions as multiple sclerosis, Parkinson's disease, Alzheimer's disease, ALS, and dementia.

Normally, the "feel" and "express" parts of your brain work together. But with PBA, the expressive part of your brain can trigger behaviour on its own. Laughing or crying can happen at any time, no matter what you're feeling.

What are the symptoms?

When you have PBA, you may suddenly cry or laugh for no reason and may have trouble controlling how long or intensely you cry or laugh. You may also feel none of the usual relief after crying or laughing.

How is it diagnosed?

Your doctor can diagnose PBA based on your symptoms and behaviour, along with looking at your past health. PBA is sometimes mistaken for depression or bipolar disorder.

How is pseudobulbar affect (PBA) treated?

PBA is treated with medicines that affect certain brain chemicals, such as antidepressant medicines.