MediaLab 2008 Progressive Ratio Rewards?

[niclab]

Would it be possible to set up media lab to reward button pressing with a preselected video on a progressive ratio schedule?

[jsimons]

I think the easiest way to achieve what you describe would be to use scale-response trials for each button press, and then insert the video item at the appropriate intervals. So, for example, you could have five scale-response trials (where participants have the opportunity to press a button) followed by the reward video, then 10 scale response trials followed by the video, then 20 trials and so on.

In each scale-response trial, you can also include a second 'exit' button, which will skip participants past all the remain trials. This would allow you to assess break point (as the skipped trials will have missing data).

I've put together a small example illustrating what I mean. I used a small number of trials and just put in a screen saying 'REWARD' where the video would go, but it hopefully makes my meaning a bit clearer!