Pseudobulbar affect (PBA), also known as emotional lability, is a distinct neurologic disorder that causes sudden and unpredictable episodes of crying, laughing, or other emotional displays.

PBA impacts more than 1 million people in the United States diagnosed with neurologic disease or brain injury, such as multiple sclerosis (MS), amyotrophic lateral sclerosis (ALS), Parkinson's disease, dementias including Alzheimer's disease, stroke, and traumatic brain injury.