MAPT and frontotemporal dementia: For example, neuropathological studies of FTD suggest the preservation of cell density in the locus coeruleus, and noradrenaline levels are normal or even elevated in the frontal lobe (Vermeiren et al., 2016), despite the presence of pathological tau inclusions (Nagaoka et al., 1995; Yang and Schmitt, 2001; Brunnström et al., 2011; Irwin et al., 2016).