The color used to overwrite a stimulus when it is erased.
<button> <clock> <picture> <shape> <text> <video>
The following trial erases the color of a text stimulus to black or white based on whether or not the response to the previous trial was correct:
<trial feedback>
/ontrialbegin = [ if (trial.test.correct == true) text.target.erasecolor = black; else text.target.erasecolor = white; ]
/ stimulusframes = [1=feedback]
</trial>