Hi everyone. I'm trying to modify my 2AFC experiment to include interleaved adaptive staircasing. I'm a relative newcomer to both Matlab and vision research. I've read through all of the online psychtoolbox documentation and the posts in this forum regarding quest, but I'm still struggling to have even a basic working quest code. I have two major issues at this point.
(1) I'm unsure how to tell the quest function whether the subject gave a correct or incorrect response. In the sample code found in the QuestDemo function this seems to work correctly, yet I'm not catching exactly how this is determined.
(2) I'm also having some difficulties figuring out how to use the output from the QuestMean function to call the desired stimuli. I've created all of my stimuli outside of Matlab with Autodesk, so they are currently on a linear scale based on the rendering frame from Autodesk (i.e, I call them using the numbers 1-10). Currently I have this code to convert them from the log scale quest uses and keep them within the range I can use:
tTest=QuestMean(q1);
% 0.03 s
int = abs(10 ^ tTest);
int = min (int,1);
int = max (int,10);
In addition, if anyone could provide an example of a 2AFC experiment that uses quest that would help immensely. Thanks for any guidance you are able to provide.
Eric
(1) I'm unsure how to tell the quest function whether the subject gave a correct or incorrect response. In the sample code found in the QuestDemo function this seems to work correctly, yet I'm not catching exactly how this is determined.
(2) I'm also having some difficulties figuring out how to use the output from the QuestMean function to call the desired stimuli. I've created all of my stimuli outside of Matlab with Autodesk, so they are currently on a linear scale based on the rendering frame from Autodesk (i.e, I call them using the numbers 1-10). Currently I have this code to convert them from the log scale quest uses and keep them within the range I can use:
tTest=QuestMean(q1);
% 0.03 s
int = abs(10 ^ tTest);
int = min (int,1);
int = max (int,10);
In addition, if anyone could provide an example of a 2AFC experiment that uses quest that would help immensely. Thanks for any guidance you are able to provide.
Eric