A principal component analysis (PCA) of the neurodegenerative diseases based on the frequency of different types of spatial pattern: Alzheimer’s disease (AD), Pick’s disease (PiD), corticobasal degeneration (C), progressive supranuclear palsy (PSP), dementia with Lewy bodies (D), multiple system atrophy (MSA), neuronal intermediate filament inclusion disease (NIFID), frontotemporal lobar degeneration with TDP-43 proteinopathy (FTLD-TDP)