Summary of: Distinct Components of Spatial Learning Revealed by Prior

Training and NMDA Receptor Blockade

Presentation By:Carmine CicconeSpencer Jenkyns

Jared KunarBrooke MacKinnon

Malcolm Pilgrim

Overview

Four experiments to come to an accurate conclusion

What is Spatial Learning? How does the Hippocampus play a

role in spatial learning? What is an LTP? What role do NMDA receptors play in

LTP?

Brooke MacKinnon

Experiment 1Methods Lister rats had to complete a Morris

Water Maze test Rats were affixed with minipumps

and divided into two groups: AP5 and aCSF

One trial per day and could not complete transfer tests

Brooke MacKinnon

Experiment 1Results AP5 prevents learning ~20µM of AP5 required to block

NMDA receptors

Brooke MacKinnon

Experiment 1Conclusion AP5 has an affect on learning the

task

Brooke MacKinnon

Experiment 2Method Rats were trained to complete a

Morris Water Maze task in a training room

Minipumps with either AP5 and aCSF were added to the test rats and control rats respectively

Rats were tested in a different room than they were trained

Malcolm Pilgrim

Experiment 2Results

Rats that received AP5 were still able to learn

Learning was slower than control group Both control and test rats always looked

into the same quadrants as they were trained

Malcolm Pilgrim

Experiment 2Conclusions Spatial pre-training ameliorated AP5

deficit The level of AP5 given was enough

for the prevention of LTP Was not solely a drug disruption

Malcolm Pilgrim

Experiment 3Method Three groups of rats were made:

Ibutenic acid lesioned group Sham surgery group Control group

Rats were trained in a separate room from where they were tested in

Malcolm Pilgrim

Experiment 3Results Lesioned induced deficit in escaped

latency and transferred test performance was apparent.

Malcolm Pilgrim

Experiment 3Conclusion Spatial learning is dependant of the

hippocampus in this task

Malcolm Pilgrim

Experiment 4Method Curtains were placed around the

Morris Water Maze to prevent the rats from using outside cues

Platform was placed in different locations within the water maze

Repetition of experiment 1

Carmine Ciccone

Experiment 4Results The AP5 Defecit returned

Carmine Ciccone

Experiment 4 Conclusion Non-spatial learning is not sufficient

to prevent the AP5 deficit.

Carmine Ciccone

Conclusions

Rats that were not pre-trained with AP5 showed no evidence of learning

Rats with non-spatial pre-training showed an intermediate amount of learning with AP5

Rats with spatial pre-training largely ameliorated the learning deficit

Carmine Ciccone

References

Title Slide Image: http://www.6seconds.org/images-static/neuron.jpg

All graphs taken from: Bannerman, D. M., Good, M. A., Butcher, S. P., Ramsay, M., & Morris, R. G. M. (1995). Distinct components of spatial learning revealed by prior training and NMDA receptor blockade. Nature, 378,182-186.