Orientation

Stimulus

Setup 1 and setup 3 have different stimulus orientation. The following two stimuli can get used to test the stimulus orientation on a setup. File:Test orientation.zip

In 2022, the orientation of the stimulus as seen by the retina were as follows:

Setup 1:

- MB0_deg: goes from front (ventral / curtain) to back (dorsal)

- MB90_deg: goes from right to left

Setup 3:

- MB0_deg: goes from back (dorsal) to front (ventral / curtain)

- MB90_deg: goes from right to left

If you design a stimulus in QDSpy you can check its orienation by playing these stimuli and your stimulus. Per default the stimulus will look as follows in QDSPy on your own screen:

- MB0_deg: goes from right to left

- MB90_deg: goes from bottom to top

Here are visual explanations:

Setup 1:

Setup 3:

Igor

If you open a file in Igor (ScanM) and display it with e.g. Automated Cell Label, it will look something like this. The center coordinates (which is also the stimulus center) will be like this. Note the flip of x and y and the signs:

Here are how the axis are relative to the retina:

So if you subtract the position of the optic-disk to go from absolute values for XCoord_um and YCoord_um to relative values rel_XCoord_um and rel_YCoord_um:

1. rel_XCoord_um < 0 means dorsal
2. rel_XCoord_um > 0 means ventral
3. rel_YCoord_um < 0 means temporal (right retina) or nasal (left retina)
4. rel_YCoord_um > 0 means nasal (right retina) or temporal (left retina)