Distinct Components of Spatial Learning Revealed by Prior Training and NMDA Receptor Blockade

1. Distinct Components of Spatial Learning Revealed by Prior Training and NMDA Receptor Blockade D.M. Bannerman, M.A. Good, S.P. Butcher, M. Ramsay & R.G.M. Morris • GROUP A3 • Bonnie Chan | Anastasia Christopher | Herman Gill • Marisa Leung | Sarah McNeil | Carol Rego

2. Carol Rego Table of Contents • Overall Evaluations • Methodological Critiques • Unexplored Pathway of LTP • Age and Gender Anomalies • Pharmacological Side Effects • Alternate Interpretation of the Results • Further Exploration

3. Carol Rego Overall Evaluations • The purpose of the study was very non specific, which allowed for further exploration during the course of the study.

4. Carol Rego Overall Evaluations

5. Carol Rego Overall Evaluations NMDA receptors are not necessary for all hippocampus dependant spatial learning, but NMDA receptor dependant plasticity is dependent on the hippocampus for its expression.

6. Herman Gill Unexplored Pathway of LTP • Study focused on hippocampus • Actually three different pathways

7. Herman Gill Unexplored Pathway of LTP

8. Herman Gill Unexplored Pathway of LTP Perforant Mossy Fibre Schaffer Collateral

9. Herman Gill Unexplored Pathway of LTP LTP is NMDA-independent in mossy fibre pathway Perforant Mossy Fibre Schaffer Collateral

10. Herman Gill Unexplored Pathway of LTP • In CA1 and DG • NMDA responsible for LTM retrieval • In CA3 • NMDA responsible for spatial recognition LTM Retrieval Spatial Recognition

11. Bonnie Chan Age Anomalies • Difference in performance with regards to age • Declines continuously beginning at earliest age

12. Bonnie Chan Gender Anomalies

13. Bonnie Chan Pharmacological Side Effects • Common critique/concern • Effects of the drugs used to block NMDA receptors not well researched • Side effects may cause a decrease in performance • (i.e.) due to drowsiness, disorientation • Solution  Gene knockout?

14. Anastasia Christopher Alternate Interpretation • Stress Impairs Performance in Spatial Water Maze Learning Tasks (1999) • By Christian Holscher

15. Anastasia Christopher Alternate Interpretation • Stressful situations • Stress can impair performance on specific activities • How altered fear conditions and stress perception can account for the impaired spatial learning

16. Anastasia Christopher Alternate Interpretation • Findings: • Stress can cause amnesic symptoms in working memory • Non-handled rats were slower in a spatial learning task

17. Anastasia Christopher Alternate Interpretation

18. Anastasia Christopher Alternate Interpretation • Connection: • Alternative interpretations for this research paper • Experiment 2  no deficit; handling • Experiment 3  stress was not an issue • Experiment 4  extramaze cues

19. Sarah McNeil Further Studies

20. Sarah McNeil Further Studies – Conclusion There is lots of evidence to suggest that LTP might be similar to the neural mechanism that the brain uses in learning and memory but the conclusion can not be made that the mechanisms are the same.

21. Carol Rego Conclusion   

22. This concludes our presentation We will be happy to address any questions you may have