with this late stage of the disease when left untreated. GPI differs from mere paresis, as mere paresis can result from multiple other causes and usually does not affect cognitive function. Degenerative changes caused by GPI are associated primarily with the frontal and temporal lobar cortex. The disease affects approximately 7% of individuals infected with syphilis, and is far more common in developing countries where fewer options for timely treatment are available. It is more common among men.

GPI