Fig 6. Landmark viewpoint-invariant versus viewpoint-dependent cells.

Top row: schematics of the monkey’s five different viewpoints for either the landmark immediately left or the landmark immediately right from the reward location. For every path, the landmark appears either on the animal’s left or right. A–C. Individual examples of cell activity (average and trial-by-trial raster histogram; cells numbered as in Fig 2) aligned on the landmark’s left or right entries in the animal’s field of view. The color codes correspond to the activity on the individual paths identified in the top row. Cells displayed in A and C discriminate between different viewpoints, while the cell displayed in B does not. D. Path selectivity index calculated for the different viewpoints of the landmark left or right of the reward (best landmark for each cell). In red are cells for which the index was significantly higher from chance (viewpoint dependent), and in blue are cells for which the index was significantly lower than chance (viewpoint invariant). The distribution of indices for the surrogate spike sets is shown in dashed green. Underlying data can be found at http://dx.doi.org/10.6080/K0R49NQV.