Labile affect

Labile affect or Pseudobulbar affect refers to the pathological expression of laughter, crying, or smiling. It is also known as "Emotional Lability", "Pathological Laughter and Crying", "Emotional Incontinence", or, more recently, "Involuntary Emotional Expression Disorder (IEED)". Patients may find themselves laughing uncontrollably at something that is only moderately funny, being unable to stop themselves for several minutes. Episodes may also be mood-incongruent; a patient might laugh uncontrollably when angry or frustrated, for example.
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