title: Medial septal microinfusion of scopolamine disrupts hippocampal activity and trace jaw movement conditioning.
abstract: This study investigated the effects of microinfusion of scopolamine into the medial septum (MS Scp) on hippocampal neurophysiology and learning of the rabbit's classically conditioned jaw movement response. The percentage of hippocampal theta slow waves (2-8 Hz) decreased after drug infusion in the MS Scp group but did not change in control groups that received infusion of saline into the MS or scopolamine into the cortex. Unit recordings from the MS Scp group showed significantly smaller conditioning-related hippocampal neural responses than seen in controls, and during conditioning, rabbits in the MS Scp group took significantly longer to reach learning criterion than either control group. Thus, the neural and behavioral impairments previously reported for systemic muscarinic blockade were reproduced by microinfusions restricted to the medial septal nucleus.
authors.affiliation: Department of Psychology, Miami University, Oxford, Ohio 45056, USA.
authors.forename: Y
authors.initials: Y
authors.lastname: Asaka
authors.forename: M A
authors.initials: MA
authors.lastname: Seager
authors.forename: A L
authors.initials: AL
authors.lastname: Griffin
authors.forename: S D
authors.initials: SD
authors.lastname: Berry
mesh_terms: D000818:Animals; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000187:drug effects; D003214:Conditioning, Classical / Q000187:drug effects*; D006624:Hippocampus / Q000187:drug effects*; D008409:Mastication / Q000187:drug effects*; D009434:Neural Pathways / Q000187:drug effects; D017966:Pyramidal Cells / Q000187:drug effects; D011817:Rabbits; D012601:Scopolamine / Q000494:pharmacology*; D012686:Septal Nuclei / Q000187:drug effects; D012688:Septum Pellucidum / Q000187:drug effects*; D009435:Synaptic Transmission / Q000187:drug effects*; D013826:Theta Rhythm
chemical_list: D012601:Scopolamine