The electrode was viewed by direct ophthalmoscopy and, in this set of experiments, positioned to record from the area centralis.
For example, the ocular dominance columns representing regions around the area centralis in area 17 are less densely labeled compared to more peripheral retinal representations.
Retinal landmarks (optic disk and area centralis) were projected onto a plotting screen with a reversible ophthalmoscope.
The cross marks the approximate position of the area centralis.
Note that at least three cells were exceptions to this trend with preferred directions towards the area centralis.
Each pixel corresponded to approximately 1 of a degree in the 4 area centralis.
The highest densities of cells were located in region of ventro-temporal retina, subtending a frontal visual axis, but there was no well-defined area centralis.
The highest densities of neurones in the ganglion cell layer were in temporal retina but no well-defined area centralis was observed.
