Spatial Learning Depends on Both the Addition and Removal of New Hippocampal Neurons (original) (raw)
Figure 8
Spatial Learning Depends upon a Selective Stabilization Process Where the Production of New Neurons Is Followed by an Active and Selective Removal of Others
The early phase of learning in the water maze, characterized by a fast improvement in performance, increases the survival of newborn neurons that were produced 1 wk before exposure to the task. Once the task has begun to be mastered, during the late phase of learning, learning induces apoptosis of newborn neurons that are a few days younger than the ones for which survival has been increased. This wave of cell death is followed by an increase in cell proliferation. Learning-induced apoptosis plays a pivotal role in this intermingled chain of events since it is necessary for the survival of the older, newly born neurons, but also for the increase in cell proliferation occurring during the late phase of learning.