What is pseudobulbar affect (PBA)?
Pseudobulbar affect (PBA) is a neurological condition that causes outbursts of uncontrolled or inappropriate laughing or crying. It is also known by other names including emotional lability, pathological laughing and crying, involuntary emotional expression disorder, compulsive laughing or weeping, or emotional incontinence. PBA is sometimes incorrectly diagnosed as a mood disorder – especially depression or bipolar disorder.
Although episodes of laughing or crying may seem appropriate for the triggering event (a thought, seeing or hearing something funny or sad), they tend to be more difficult to restrain (are ‘closer to the surface’) and can be more intense and last longer than would ordinarily be expected. However, they can also be relatively minor and subtle, such as getting choked up or a brief giggle.
PBA can have a substantial impact on the lives of those experiencing the condition, and on their family members and caregivers. It can cause embarrassment and anxiety, leading to withdrawal and social isolation. It creates an additional burden for patients who already have a serious underlying neurologic condition.
How common is pseudobulbar affect (PBA)?
It is estimated that between 2 and 7 million people in the United States have PBA depending on the severity of symptoms, with the lower number representing individuals with more severe symptoms.
What are the symptoms of pseudobulbar affect (PBA)?
- Uncontrolled or sudden outbursts of laughing or crying usually in response to a triggering event with an emotion either appropriate or inappropriate to the event.
- Laughing or crying that is out of proportion to the trigger and mood or inner feelings of the person. The person may also start laughing or crying for no apparent reason.
- Emotional outbursts that are more intense, frequent, or exaggerated than previously experienced by the individual.
- Outbursts of anger or frustration may also occur.
What causes pseudobulbar affect (PBA)?
It is not completely known why pseudobulbar affect (PBA) occurs, but it is essentially always associated with neurological disorders or diseases that cause brain damage or injury. Disorders, diseases, or injuries that are associated with PBA include:
- Alzheimer’s disease and other forms of dementia
- Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig’s disease
- Brain tumors
- Cerebellar lesions (including spinocerebellar atrophy)
- Multiple sclerosis (MS)
- Neurosyphilis (an infection in the brain or spinal cord caused by spirochetes that causes syphilis)
- Parkinson’s disease
- Progressive supranuclear palsy (a brain disorder that causes problems with walking, balance, speech, thinking, vision, mood and behavior)
- Traumatic brain injury
- Wilson disease (a disorder in which copper builds up in the brain, liver and other organs)
PBA occurs when there is a lack or loss of voluntary control over emotional responses. Various brain regions along a cerebro-ponto-cerebellar pathway are likely responsible for a loss of inhibitory or regulatory control on expression of emotions. Part of this pathway includes the cerebellum, which plays a key role in modulating or monitoring emotional responses and ensures they are appropriate to the social situation. Disruption of the neural (nerve) pathways from certain areas of the brain to the cerebellum may lead to a loss or lack of control over emotional expression.
Neurotransmitters, such as serotonin, norepinephrine, dopamine, and glutamate, are also thought to play a role in PBA.