Toronto, ON (July 10, 2026) — A new brain imaging study led by researchers at the Centre for Addiction and Mental Health (CAMH), published in eBioMedicine, provides the strongest evidence to date that long COVID is associated with injury to dopamine-releasing neurons in the brain—a finding that may explain symptoms such as lack of motivation due to fatigue, slowed movement, and memory difficulties, and could open the door to new treatment strategies.

Long COVID is estimated to affect five per cent of the world population, including two million Canadians, and is characterized by a wide range of persistent and sometimes debilitating symptoms, including brain-related ones such as fatigue, brain fog, memory problems, or low mood, that continue for at least three months following the initial COVID-19 infection. Despite its prevalence, no evidence-based treatments currently exist, largely due to limited understanding of the underlying brain pathology.

In the new study, researchers used positron emission tomography (PET) brain imaging to measure a well-established marker of dopamine neuron integrity in people with long COVID and healthy individuals.