Multiple sclerosis (MS) is a chronic neurological disease that affects the central nervous system. It often results in physical, cognitive, and emotional symptoms that can significantly impact a person’s quality of life. One common but not often discussed symptom of MS is pseudo-bulbar affect (PBA), which can cause uncontrollable laughing and crying.
What is Pseudo-Bulbar Affect (PBA)?
Pseudo-bulbar affect (PBA) is a condition characterized by sudden and uncontrollable episodes of crying and/or laughing. It is caused by damage or dysfunction in the areas of the brain that control emotional expression. In people with MS, this damage is often caused by lesions or scarring in these regions of the brain.
During a PBA episode, a person may laugh or cry very intensely for no clear reason or in response to stimuli that normally would not evoke such an emotional reaction. The laughing and crying spells typically last from a few seconds to several minutes. The person often feels as if they have no control over these emotional outbursts.
PBA occurs secondary to neurological conditions such as amyotrophic lateral sclerosis (ALS), Alzheimer’s disease, stroke, traumatic brain injury, and most commonly, MS. It is estimated that 10% of people with MS experience PBA at some point.
MS lesions affecting emotional control
In MS, lesions caused by the immune system attacking the myelin sheath around nerves can occur anywhere in the brain or spinal cord. When lesions form in areas involved in regulating emotional expression, they can cause pseudobulbar affect.
The main areas impacted in PBA are:
- The cerebellum – important for coordinating movement and some cognitive functions.
- The brainstem – relays signals between the brain and body and contains centers that control facial muscles and tearing.
- Frontal and temporal lobes – involved in personality, behavior, and emotion regulation.
When these regions become damaged, signals between the brain and facial muscles become disrupted. This impairs a person’s ability to control laughing/crying even if their feelings don’t match the emotional expression.
Symptoms of PBA in MS
The main symptoms of PBA are:
- Episodes of sudden uncontrollable laughing or crying – These emotional outbursts occur randomly and are disconnected from the person’s internal emotional state at the time.
- Inappropriateness of the laughing/crying – The episodes occur at unusual times or are excessive emotional reactions to minor stimuli.
- Lack of control – The person is unable to control or stop the laughing/crying once an episode starts.
Other symptoms may include:
- Mood swings
- Difficulty transitioning between emotional states
- Personality changes
- Depression
- Difficulty connecting with others
The pseudobulbar affect is distinct from regular crying caused by sadness, grief, pain, etc. With PBA, the laughing or crying spell is involuntary and occurs even if the person’s underlying mood state does not match.
Causes of PBA in MS
The exact causes of PBA in people with MS are not fully understood. The main factors believed to contribute to PBA include:
- Brain lesions – Plaques of scar tissue that disrupt communication between brain regions involved in regulating emotions.
- Neuronal dysfunction – Impaired signaling between nerves caused by MS. This affects control of facial expressions and tearing.
- Neurotransmitter imbalances – Changes in brain chemicals like serotonin due to MS damage.
- Medications – Some drugs used to treat MS symptoms may increase PBA episodes as a side effect.
In most cases, PBA occurs because of cumulative MS-related damage rather than acute lesions. It may take time for symptoms to appear as disruption in emotional signaling progresses.
Diagnosing PBA in MS
There are no specific tests that can definitively diagnose PBA. Doctors will evaluate the following factors:
- Medical history – Determine if episodes match PBA criteria.
- Neurological exam – Assess areas impacted by MS.
- Emotional assessment – Evaluate mood disorders or other causes.
- Imaging – MRI can reveal MS lesions in relevant brain regions.
PBA must be differentiated from normal crying triggered by emotions or depression. Doctors may use rating scales like the Center for Neurologic Study Lability Scale to quantify PBA severity.
How PBA impacts quality of life with MS
PBA can significantly affect a person’s quality of life with MS in many ways:
- Social isolation – Embarrassment about frequent laughing/crying episodes may cause withdrawal from social situations.
- Stigma – Others may not understand PBA is involuntary and assume the person is overly emotional.
- Relationship difficulties – Partners may feel overwhelmed by frequent intense displays of emotion.
- Career impact – PBA episodes may limit some work abilities, especially jobs requiring emotional regulation.
- Mood disorders – PBA is linked to higher rates of anxiety, depression, and emotional lability.
- Reduced motivation – Coping with disruptive PBA episodes causes fatigue and affects self-esteem.
PBA presents an additional challenge on top of usual MS symptoms. Seeking treatment can help reduce PBA frequency and severity.
PBA Treatment Options
While no treatments can eliminate PBA completely, the following options may help reduce episode frequency and improve control:
- Medications – Antidepressants like SSRIs or tricyclics are commonly prescribed “off-label” to treat PBA.
- Behavioral techniques – Breathing exercises, relaxation strategies, and counseling help manage outbursts.
- Triggers avoidance – Preventing known triggers like stress, fatigue, alcohol can reduce episodes.
- Support groups – Connecting with others experiencing PBA provides validation and coping strategies.
If no underlying cause for PBA like MS is identified, it may be classified as primary PBA. This type usually shows better response to treatments than PBA caused by neurological disease.
Conclusion
Pseudobulbar affect is a common symptom of MS that causes uncontrollable, inappropriate laughing and crying. It is often overlooked but can significantly impact quality of life. PBA results from lesions damaging emotional control regions in the brain. Diagnosis involves ruling out other causes of uncontrolled emotion. While not curable, PBA episodes can be managed through medications, behavioral approaches, trigger avoidance, and support groups. Seeking treatment is important to help minimize the frequency and impacts of PBA on daily living.