SNCB and Alzheimer disease: Aggregates of α-synuclein form Lewy bodies, and in patients with dementia and LB, the α-synuclein that forms the LB was almost absent when the cortical neurons contained β-synuclein [6], whereas in patients’ brains showing either LB pathology alone or LB pathology plus Alzheimer’s dementia all cortical areas showed a greatly diminished expression of β-synuclein [7].