By mrg4 - 1/4/2016
for an experiment we want to use a different form of response than usual. We want the participant to press a key in order to start a video sequence and that he keeps pressing the key throughout the clip. Whenever a critial situation occurs he should lift his finger. This procedure is quite similar to a "dead man's switch".
I found no solution to this approch, so I hope you can help us.
By Dave - 1/4/2016
If you are using Inquisit 3 (which I assume, because you posted in the Inquisit 3 forum), this is not possible: Inquisit 3 does not have the capability to register key releases.
Inquisit 4, on the other hand, does have that capability. To define a key release as response, you prepend a minus-sign to the respective key's scan code.
/ validresponse = (-57)
would consider the release of the space bar a valid response.