Medical Terminology for Inappropriate Laughter
The medical term for inappropriate laughter is "pathological laughter" or "pseudobulbar affect" when it occurs as part of a broader syndrome of emotional dysregulation.
Definition and Characteristics
Pathological laughter is defined by several key features:
- Involuntary and inappropriate outbursts of laughter that are unrelated to the person's internal emotional state 1
- Laughter that is unrestrained, forced, or uncontrollable 1
- Absence of voluntary control over the laughter episodes 2
- Dissociation between the laughter and any appropriate stimulus 1, 2
Underlying Conditions
Pathological laughter can occur in association with various medical conditions:
- Pseudobulbar palsy: A neurological condition affecting the corticobulbar tracts, causing emotional disinhibition 1, 3
- Neurological disorders: Including stroke, multiple sclerosis, amyotrophic lateral sclerosis, traumatic brain injury, and dementia 3
- Gelastic epilepsy: A rare form of epilepsy where laughter is the main seizure manifestation 1
- Psychiatric conditions: Various psychiatric disorders may present with inappropriate laughter 1
- Gilles de la Tourette syndrome: Can manifest as a phonic tic accompanied by premonitory urges 4
- Post-traumatic stress disorder: In rare cases, can present as a monosymptomatic condition 2
- Vascular events: Such as severe vasospasm following subarachnoid hemorrhage 5
Neuroanatomical Basis
The neuroanatomy of pathological laughter involves several levels:
- Cortical level: Particularly the prefrontal cortex, which is involved in emotional regulation 1, 5
- Bulbar or effector level: Involving brainstem structures that control facial and respiratory patterns 1
- Integrative level: Likely near the hypothalamus, coordinating emotional responses 1
Differential Diagnosis
It's important to distinguish pathological laughter from:
- Emotional lability of organic brain syndromes 2
- Inappropriate jocularity associated with frontal lobe disturbance 2
- Intoxication effects from alcohol or drugs 2
- Manic syndromes with typical symptoms like grandiose self-esteem and flight of ideas 2
Clinical Assessment
When evaluating a patient with inappropriate laughter:
- Assess for neurological signs and symptoms, particularly those suggesting pseudobulbar palsy 3
- Look for associated symptoms like crying episodes, as pathological laughter often co-occurs with pathological crying 3
- Document the context, frequency, and triggers of laughing episodes 3
- Evaluate for comorbid conditions, especially in cases resembling tic disorders 4
Treatment Options
Treatment approaches for pathological laughter include:
- Selective Serotonin Reuptake Inhibitors (SSRIs): Sertraline has been shown to be effective in treating pathological laughter 5
- Dextromethorphan/quinidine combination: Shows promise as a potential therapy for pseudobulbar affect 3
- Antidepressants: Various antidepressants have shown varying levels of success 3
- Dopaminergic agents: May be beneficial in some cases 3
Clinical Importance
Recognition and treatment of pathological laughter is important because: