The hippocampus and spatial memory
Overview
There are place cells in the HC (= encode Space/ where the mouse is). Place cells integrate a bunch of features like Smell, Background Noise, Visual image of a corner, Texture of the
Floor, Somato Sensory.
In an experiment with the Morris Water Maze (behavioral test, milky water (=> cannot see), goal is to find a platform so the mouse can rest) the control group can after some trials search for the platform and find it. Mice where the NMDA receptors in the HC are blocked however randomly search the water and do not learn.
How can we measure neuronal plasticity in the HC ?
We can in vitro (post partem) stimulate well-known pathways with electrodes and record the potential of different stimuli. The most studied synapses are CA3->CA1.
Paired pulse facilitation
If we stimulate twice shortly with a small delay, there will be an overlap and there will be higher depolarization. It is an example for short-term Plasticity.