What is Progressive Supranuclear Palsy? The Rare Dementia that Rev. Jesse Jackson Had

After decades of activism, Reverend Jesse Jackson passed away on Feb. 17 from complications caused by a rare form of dementia called progressive supranuclear palsy (PSP).

Over his lifetime, Jackson campaigned with Martin Luther King Jr., received a Presidential Medal of Freedom, ran as a Democratic Presidential candidate and even negotiated global hostage releases

In 2017, Jackson publicly announced his Parkinson’s diagnosis. Jackson was initially misdiagnosed, like many people with PSP, and it took until April 2025 for him to learn it was PSP. While they share some movement-related symptoms with Parkinson’s, people with PSP have different types of protein aggregates in their brain and do not respond to Parkinson’s medications.

While it is less well-studied than other dementias, scientists are starting to make headway in understanding PSP.

What is PSP and how is it different from Parkinson’s?

PSP is a rare form of dementia affecting up to 30,000 Americans. While it shares some symptoms with Parkinson’s, it progresses faster, affects eye movements making it difficult to look up or down and control eyelids, and leads to cognitive changes earlier on. 

One of the other differentiating symptoms is unprovoked falls, caused by neurodegeneration in the brain. While problems with balance and falling also occur in Parkinson’s, they’re more common in the more advanced stages. PSP also causes slurring with speech, changes to mood and personality, as well as difficulty swallowing. 

The other major difference between the two diseases are the protein aggregates linked to progressive cell death. In Parkinson’s, the dopamine-producing brain cells in the substantia nigra region of the brain start to accumulate deposits of abnormal alpha-synuclein protein, leading to cell death and affecting a person’s ability to regulate their movement. Meanwhile in PSP, tau tangles that accumulate and spread throughout the brain are the major drivers of the disease. 

Diagnosis and treatment of PSP

Right now, diagnosis of PSP is made on the basis of clinical symptoms. While there are 30 specialty Centers of Care for PSP in the U.S., the waitlist is far too long to see every person who doctors suspect might have the disease. 

Biomarkers could allow doctors to make the process more efficient, and cut down on misdiagnosis, and gain insight into disease progression. Currently, some 60 percent of patients report being misdiagnosed. 

The tau that forms in PSP is different structurally than the tau that’s linked with Alzheimer’s. As a result, blood and cerebrospinal fluid-based biomarkers like pTau-217 and pTau-181 that could help confirm tangles in Alzheimer’s, don’t work for PSP.

Instead, researchers are testing a skin biopsy that could detect the abnormal form of tau specific to PSP, across Europe and North America. If it works, it could provide a new tool for doctors to use within the next few years, and could open the door for screening participants into clinical trials. 

For now, treatment focuses on medications that manage symptoms and physical therapy to improve independence, and mobility while reducing falls.