HSPB1 and mild neurocognitive disorder: The proportion of cases in each diagnostic category showing HSP27 immunoreactive neurons and/or glial cells was highly significantly different between FTLD (overall), AD, MND and control groups for frontal cortex (neurons: χ2 = 20.8, P =0.001; glial cells of grey matter: χ2 = 15.9, P =0.003; glial cells of white matter: χ2 = 28.8, P =0.000) and temporal cortex (glial cells of grey matter: χ2 = 15.8, P =0.001; glial cells of white matter: χ2 = 23.0, P =0.000) and marginally significant for temporal cortical neurons (χ2 = 6.8, P =0.080).