DISCLAIMER: This article discusses the subject of mental health, and also contains minor spoilers for the 2019 film, Joker. Reader discretion is advised
It came as a surprise to no-one when Joaquin Phoenix received the Academy Award for Best Actor at the 92nd Oscars Ceremony, coming off of the success of perhaps the most notable performance of his career – the infamous Batman villain in the 2019 origin film, Joker.
The film is said to deal with the theme of mental illness and its effects, with Variety writing that ‘Phoenix is astonishing as a mentally ill geek who becomes the killer-clown Joker’. His unique yet-faithful take on the legendary comic book character was seen as a highlight of the film, and many audiences cited the character’s tendency to break out in uncontrollable fits of laughter as a particularly memorable aspect. Several times during the film, he hands out a card to explain that his fits are the result of a chronic condition he suffers from. While this condition is left un-named in the film, it bears a resemblance to the real-life disorder of pseudobulbar affect (PBA), although this claim has been disputed by the actor, who prefers to leave Joker’s ‘affliction‘ more ambiguous in nature.
Pseudobulbar affect (pseudobulbar: from lesions in the brain / affect: external manifestation of one’s internal state), also known as emotional incontinence, is a little-known condition that was first diagnosed in the 19th century. ‘Affect’ is generated by several brain regions:
- Executive function in the Prefrontal Cortex
- Control of movement in the Motor Cortex
- Coordination of movement in the Cerebellum
- Expression of appropriate emotions (affect) via the Brainstem
But for many people who suffer from a wide variety of neurological conditions or injuries (including dementia or schizophrenia) that cause a ‘disconnection’ between these brain regions, affect is not so natural; instead, they present with uncontrollable and abnormal expressions of emotion that are at best confusing and, at worst, embarrassing to the point of severe social awkwardness. This includes episodes of ‘pathological laughter / crying’ that:
- are triggered by non-emotive cues (i.e. for no apparent reason)
- can form an exaggerated response to an emotional stimulus OR
- are completely inappropriate to the situation (e.g. laughing in response to sad news)
The symptoms of PBA can be severe, with persistent and unremitting episodes. Characteristics include:
- The onset can be sudden and unpredictable, described by some patients as coming on like a seizure
- The outbursts have a typical duration of a few seconds to several minutes
- The outbursts may happen several times a day
Treatment of this “laughing disorder” is difficult without an in-depth understanding of its causes. Current therapies include antidepressant drugs, although these have had only moderate success. Instead, the American Stroke Association offers a list of coping techniques, such as deep breathing or posture changes. However, these are purely symptomatic in nature and do nothing to target the origins of PBA.
There are thought to be around 1-2 million people with PBA in the United States, although this is widely speculated to be inaccurate due to misdiagnoses and clinical under-reporting of the disorder. In a 2013 study into the prevalence and possible causes of PBA, just over 5 thousand subjects were screened for significant symptoms of the disorder. All of the participants had an existing neurological disorder, including Alzheimer’s disease, Parkinson’s disease, multiple sclerosis, stroke or traumatic brain injury. People with the latter two conditions showed the highest rates of PBA diagnosis. Since the origins of PBA are unclear, the results of this study suggest that injury to the upper neural networks (controlling motor responses to emotion) in the brain may be involved in the development of the condition. Thus, treating the existing neurological disorders underlying PBA may provide a treatment strategy for those, like the unfortunate Arthur Fleck, suffering from the condition.
