The phenomenon of uncontrollable, inappropriate laughing or crying, often depicted in popular culture, is a recognized medical condition known as Pseudobulbar Affect (PBA). This disorder is neurological, meaning it originates from a physical change or injury within the nervous system, rather than being a primary psychiatric illness. PBA causes sudden, frequent, and intense emotional outbursts that are disproportionate to, or completely incongruent with, the person’s actual internal mood. The condition can be highly distressing for those affected, leading to social isolation and significant embarrassment.
Defining Pseudobulbar Affect
Pseudobulbar Affect is characterized by episodes of crying or laughing that are involuntary and difficult to control, sometimes lasting for several minutes. The emotional expression—the “affect”—does not match the individual’s “mood,” which is their underlying emotional state. For example, a person may feel mildly amused but burst into intense, prolonged laughter, or feel only slightly stressed but begin an uncontrollable crying spell.
These outbursts are often triggered by minimal stimuli that would not normally cause such an extreme reaction, or they can occur without any apparent trigger at all. The episodes are typically brief, lasting from a few seconds to a few minutes, but can happen multiple times each day.
The experience is frustrating because the person is often fully aware that their emotional display is inappropriate to the situation. They may be internally calm or even experiencing an opposite emotion while their face and body express intense, exaggerated sadness or mirth. This lack of control over emotional expression is why the condition has historically been referred to by terms like emotional incontinence or pathological laughing and crying.
Neurological Basis and Associated Conditions
The root cause of Pseudobulbar Affect is damage or disruption to the neurological pathways that regulate emotional expression. Researchers theorize that the condition results from a “short circuit” in the connections between the cerebellum and the cerebral cortex. This disruption affects the corticopontine and corticobulbar tracts, which are responsible for modulating the motor output of emotional displays like laughing and crying.
When these tracts are damaged, the inhibitory control from the higher brain centers over the brainstem is lost or compromised. The brainstem executes the physical movements of emotional expression, and without the natural “brake,” the motor response is easily triggered and executed in an exaggerated, uncontrolled manner.
PBA is a secondary condition, meaning it always occurs as a consequence of another underlying neurological disease or injury. Common causes include stroke, which can damage the necessary brain pathways, and traumatic brain injury (TBI).
Associated Neurodegenerative Diseases
Neurodegenerative diseases frequently associated with PBA include:
- Amyotrophic Lateral Sclerosis (ALS)
- Multiple Sclerosis (MS)
- Parkinson’s disease
- Alzheimer’s disease
Differentiating PBA from Mood Disorders
PBA is fundamentally a neuropsychiatric syndrome and must be distinguished from traditional psychiatric conditions like clinical depression or bipolar disorder. The core difference lies in the nature and duration of the emotional change: PBA involves brief, intense, and involuntary episodes of emotional expression that do not reflect the patient’s sustained internal mood. Episodes of PBA last only a few seconds to minutes, and the individual’s mood quickly returns to normal afterward.
In contrast, classical mood disorders are characterized by a pervasive and sustained change in internal emotional state that lasts for weeks or months. For instance, major depressive disorder involves a continuous feeling of sadness, hopelessness, and loss of interest. While a person with depression may cry, the crying is typically congruent with their persistent sad mood and is often controllable.
Misdiagnosis of PBA as depression is common because crying is a prominent symptom in both conditions. However, a person with PBA may laugh uncontrollably in response to sad news or cry when they are not feeling sad, which is mood-incongruent behavior. Mood disorders affect the subjective experience of emotion, while PBA affects the objective, visible display of emotion.
Treatment and Management Strategies
The goal of managing Pseudobulbar Affect is to reduce the frequency and severity of the emotional outbursts. Treatment often involves pharmacological intervention, primarily using medications that impact neurotransmitter systems in the central nervous system.
Certain antidepressants, specifically selective serotonin reuptake inhibitors (SSRIs) and tricyclic antidepressants (TCAs), are frequently used off-label to manage PBA symptoms. These are typically prescribed at lower doses than those used for treating clinical depression, suggesting they regulate emotional motor pathways.
The only medication specifically approved by the Food and Drug Administration (FDA) for treating PBA is a combination of dextromethorphan hydrobromide and quinidine sulfate. This combination has demonstrated effectiveness in clinical trials, significantly reducing the number of episodes.
Non-pharmacological coping strategies also play a supportive role, focused on helping the individual navigate social situations. Distraction techniques, such as changing body position or focusing attention elsewhere when an episode is sensed, can help shorten the duration of an outburst. Educating family members and coworkers about the condition is beneficial, as it helps reduce social embarrassment.