This example illustrates two methods for clearing a stimulus display after a specified amount of time and allowing additional time for response.
The first block of trials illustrates the use of the "Jump" Response Action in combination with the Label object and extended input. In this block of trials, the stimulus is displayed for 1000 msec. If the subject responds during the stimulus, the stimulus display is terminated and the experiment proceeds directly to the feedback. This is accomplished using the "Jump" option in the Response Action field and specifying a Label. If the response does not come in during the display of the stimulus, the display is cleared, and an additional 1000 msec is allowed for response (extended input is set to 2000 in the Time Limit field). This additional time period is terminated upon the subject's response. The trial times-out if no response is entered within 2000 msec.
The second block of trials illustrates the use of the IsPending method. The Stimulus object is set to display for 1000 msec, then the WaitMore2 object is used to clear the stimulus. The duration for the WaitMore2 object is set to 0, and an InLine object is used to check for input and allow additional time if input has not been received. A Do..Until loop is used to wait until input has been received, or until the 2000 msec max time allowed for response has expired. The result is that the stimulus is always displayed for 1000 msec, and that if additional time is allotted only if the subject does not respond during the display of the stimulus. The additional time is terminated upon response. The trial times-out if no response is entered within 2000 msec.
A previous version of this sample had the Data Logging property of the stimulus objects set to "none". This has been corrected to "Standard".