Questions about RandomDotMotion adaptor

Hi
I have questions about how does the property "Interleaf" wroks in the RandomDotMotion adaptor?
Another question is that previously I training monkey with 100% coherence. When I tried to use lower coherence, the low coherence condition looks like always moving left whether the direction I set is 0 or 180. After reading the m file I find that while coherently moving dots update their location by the given speed and direction. But the Random moving dots are not moving but just Randomly change their locations when updating. How can I make the low coherence conditions looks not that strange.
Thank you so much for your help.

The Interleaf property determines how many frames later the dots presented in one frame reappear on the screen and it should be set to 3. My implementation of the random dot motion stimuli is based on the papers of Michael Shadlen's group (a.k.a. the Movshon/Newsome version). You can find the detailed descriptions about it in any of his papers, including this one. For the different algorithms of random dot motion stimuli, see this paper.

At a lower coherence level, more dots are moved to random locations, as you know from my code already. This creates an ambiguous percept and makes it difficult for you to tell which direction the dots are really moving to. It is the purpose of using the random dot motion stimuli, so I do not understand what you want to do.