The purpose of this research is to better understand how dementia affects activity in different parts of the brain.

This study will examine Positron Emission Tomography (PET) imaging with Florbetaben F18. Florbetaben F18 is a radioactive tracer that binds to particles in your brain. This process displays activity in the brain. Florbetaben F18 is a PET amyloid imaging agent approved by the United States Food and Drug Administration (FDA) to estimate the amount of beta-amyloid plaque in adult patients who are being evaluated for Alzheimer's disease and other causes of cognitive decline. The purpose of this research is to better understand how dementia affects activity in different parts of the brain. Currently, the scientific community is limited by how well it can see inside the brain. The use of a PET scan better helps us understand what the brain looks like in a diseased state. Participation in the study will help to understand what brain activity looks like, especially around language regions.

Inclusion Criteria:

• Participants must have a diagnosis of PPA or a related dementia syndrome

Exclusion Criteria:

• Pregnant
• Breastfeeding
• Receiving radiation clinically

Participants will be recruited from other research projects at Northwestern's Mesulam Center. Some of these projects recruit participants from the local Chicagoland area and others recruit participants from across the United States. As Primary Progressive Aphasia is an uncommon syndrome, participant recruitment is not focused on a specific demographic area.