[solved] How to show an error message when the user pressed a key during an advanced delay item.

mimrock

I created a simple experiment that measures the reaction time of the user. The sequence shows a message to the user to wait for the signal. Than there is a random delay with an advanced delay item and the signal is shown. The user has to press a pre-defined key as fast as possible, without making any decisions.

Now, when the user waits for the signal, I need to show an error message, and restart the sequence if the user press the pre-defined key too early. Do you have any idea to achieve this?

Edwin

The advanced_delay simply halts your experiment, so there is no room for checking for keypresses while it is active. However, keypresses made during the delay will still be registered by the back-end. With a nifty trick, you can use this to your advantage.

Untick the box labelled Flush pending keypresses in your keyboard_response. Now, if the reponse time is 0, you know a keypress has been made before the onset of the keyboard_response. All values above 0 should be fine. Therefore, you can give the error feedback when [response_time] < 1.

Good luck!