Radial arm maze. Effects of donepezil pre-treatment and 192-IgG-saporin (Sap) lesions on radial arm maze total errors (a), spatial spans (b) and perseverations (c). Donepezil pre-treatment reduced the number of errors and increased spatial span in cholinergically depleted rats. Sal-Sham vs. Sal-Sap: #p < 0.05; ##p < 0.01; ###p < 0.001; Don-Sap vs. Sal-Sap: *p = 0.05, **p = 0.01. Don-Sap, donepezil-treated Sap-lesioned rats; Don-Sham, donepezil-treated sham-lesioned rats; Sal-Sap, saline-treated Sap-lesioned rats; Sal-Sham, saline-treated sham-lesioned rats.