BACE1 and memory impairment: Moreover, in agreement with high BACE1 expression and presynaptic localization in neurons, deeper analyses of BACE1−/− mice have uncovered numerous subtle neuronal phenotypes, such as axon targeting errors [36-38], reduced myelination [39-41], memory impairments [20,30,32,42,43], reduced muscle spindles [44], neurochemical abnormalities [45], alterations in neurogenesis and astrogenesis [46], increased age-related neurodegeneration [47], reduced spine density [48], retinal pathology [49], endophenotypes of schizophrenia [48], and seizures [42,47,50] (Table 1).