SOD1 and amyotrophic lateral sclerosis: This SOD1 mouse model of familial ALS shows significant alterations in dendritic structure, including the density of dendritic spines, of primary motor cortex upper MNs (Spalloni et al., 2011; Jara et al., 2012; Fogarty et al., 2015, 2016b; Saba et al., 2015), pyramidal neurons of medial pre-frontal cortex (MPFC) (Sgobio et al., 2008; Fogarty et al., 2016c), and lower MNs in the brainstem and spinal cord (van Zundert et al., 2008; Martin et al., 2013).