Imaging study ties long COVID symptoms to dopamine neuron damage

Using PET scans, researchers found reduced markers of dopamine nerve terminals in the striatum of people with long COVID, suggesting damage to dopamine-releasing neurons. This may explain persistent fatigue, low motivation, slowed movement, and memory problems. The findings could guide new treatments targeting the dopamine system.

The study, published in eBioMedicine, used PET imaging to compare dopamine nerve terminal markers between long COVID patients and healthy controls. Reductions appeared across all major striatum regions, with symptom-specific patterns: ventral striatum losses tracked with diminished motivation, dorsal putamen losses with motor slowing, and caudate putamen losses with memory complaints. Roughly five percent of the global population—about two million Canadians—experience long COVID, yet no evidence-based treatments exist.

This work follows earlier findings from the same CAMH team showing elevated brain inflammation in regions dense with dopamine neurons. Since inflammation is known to injure these cells, the two studies together suggest a plausible injury pathway. The senior author, Dr. Jeffrey Meyer, notes this pattern mirrors other neurological conditions where dopamine loss produces similar symptoms.