jumping for any key except...

[Michal]

hi,
in my experiment, i want to allow any key press in order to proceed to the next trial, BUT only one key is the correct key. for all other keys, before proceeding to the next trial, i want to show an "error" feedback. so, i need basically to tell the system something like:

RT:38, any<999

which means that 38 is the correct key and for all other keys show an "error" message and then proceed to the next trial. the problem is that the "any" code includes the 38 code, so the system will jump to 999 for the 38 key as well as for all the others.

I played with this problem a little and found out that if i write

RT: any<999, 38

then it doesn't jump for the 38 code.
can you explain why is that? is this the correct way to do what i need?

thanks!

[jarvis24]

I believe the code is written such that codes later in the list take precedence over those earlier in the list. This is simply because the codes are read-in sequentially and so repeated codes will overwrite earlier ones. Take "rt:38,any>999". Since 38 is included in any, you get a skip when 38 is pressed. In contrast, listing 38 after any (i.e., "rt:any>999,38") allows you to give it special treatment. Unfortunately, that messes with your ability to define it as the correct response. You would have to determine it during your data analysis.

[Michal]

i just wanted to make sure that this solution will work consistently, because it is undocumented (at least from the search i made in the help files)

[jarvis24]

It ought to be documented. I'll cc this to the DirectRT suggestions area.