Increased levels of hippocampal Nogo-A showing strong positive correlation with cognitive decline in aged rats (VanGuilder et al., 2011, 2012) and cognitive impairments in a mouse model of Alzheimer’s disease can be ameliorated by genetic deletion of Nogo-A (Masliah et al., 2010). Here, RTN4 is linked to early-onset autosomal dominant Alzheimer disease.