Worked with a user today on an nback task. Like the GNAT, it's helpful to be aware that "-1" can be used as a valid response option. Like indicating "RT:57,-1" with a min-max value of 1000ms will take "no response" as the response after 1000ms and proceed as if a valid key were just hit.

See

From the section on min-max settings in the users guide, or nline here:

http://www.empirisoft.com/directrt/h..._rt_limits.htm

An alternative to using the ! symbol is to define -1 as a valid response code on your trial. That way, only trials on which -1 is given as an option will continue automatically after the maximum time has been reached. Like other codes, if -1 is listed first, then it will be considered the correct response. This option can also be combined with the ! method if you want to define no
response as correct but have automatic continuation regardless of the response. You can think of -1 as an actual "no response" button which is pressed at the
maximum response time.
Hope it helps,
Blair