Related Experiment Video
Updated: Oct 12, 2026
Whisker-signaled Eyeblink Classical Conditioning in Head-fixed Mice
Published on: March 30, 2016
Medial septal lesions retard classical conditioning of the nicitating membrane response in rabbits
Abstract:
Lesions of the medial septum were produced in 7 of 14 rabbits prior to classical conditioning of the nictitating membrane response. Lesions significantly altered the hippocampal electroencephalogram, attenuated conditioned hippocampal unit responses, and slowed the behavioral rate of acquisition. The contrast of the behavioral results with those of studies of massive septal or hippocampal ablation suggests a functional subdivision of the septo-hippocampal system in learning.
Insights
Medial septum lesions in rabbits impaired hippocampal activity and slowed learning during classical conditioning. This suggests specific roles within the septo-hippocampal system for memory formation.
Area of Science:
- Neuroscience
- Behavioral Neuroscience
- Learning and Memory
Background:
- The septo-hippocampal system is crucial for cognitive functions, including learning and memory.
- Understanding the specific roles of different septal nuclei is essential for elucidating memory mechanisms.
Purpose of the Study:
- To investigate the role of the medial septum in classical conditioning of the nictitating membrane response.
- To examine the effects of medial septal lesions on hippocampal electroencephalogram (EEG) and unit activity during learning.
Main Methods:
- Medial septal lesions were created in rabbits (n=7).
- Rabbits underwent classical conditioning of the nictitating membrane response.
- Hippocampal EEG and unit activity were recorded before and during conditioning.
Main Results:
- Medial septal lesions significantly altered hippocampal EEG patterns.
- Conditioned hippocampal unit responses were attenuated in lesioned rabbits.
- The rate of behavioral acquisition during classical conditioning was significantly slowed.
Conclusions:
- The medial septum plays a critical role in the acquisition of learned responses.
- Findings suggest a functional subdivision within the septo-hippocampal system, with the medial septum specifically involved in certain aspects of learning.
- These results differentiate the effects of localized medial septal lesions from those of broader septal or hippocampal ablations.
