correct/incorrect feedback for no response
I'm learning opensesame and from the tutorial, I saw correct/incorrect feedback for no response can be set under the condition of
[correct] = undefined and [response] = None
[correct] = undefined and [response] != None
Could you please explain why I need both correct/incorrect feedback for the no response? I'm also confused about the above condition (not sure how I know what are existing variables e.g., [correct] and [response] in opensesame that I can use for coding)
Thanks in advance!