We conclude that sparse coding (achieved here by ICA, which is is linear
and instantaneous) is a simple and efficient computational approach for the
generation of place cells from grid cells. Other linear methods, such as PCA
or linear SFA, do not work. However, the complexity of place-field generation
is now only shifted to the computation of grid-cell behavior and still open for
discussion.
Acknowledegement s
This research was funded by the Volkswagen Foundation (MF, LW) and the
Wellcome Trust (RV: 10008261).
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