Cholinergic deafferentation of the hippocampus causes non-temporally graded retrograde amnesia in an odor discrimination task.

•Infusion of 192-IgG-Saporin into the medial septum significantly reduced cholinergic input into the hippocampus.•Removal of cholinergic projections from the medial septum produced retrograde amnesia, but there was no evidence for a temporal gradient.•Infusion of 192-IgG-Saporin into the medial septum did not produce anterograde amnesia.•Using the string pulling task, mnemonic function can be evaluated, and may allow for the development of therapeutic assessment for neurodegenerative disorders.