Evaluating expressions in trigger_watch variables

ereming's Avatar


01 Apr, 2016 02:19 PM

Hi Chris,

Not sure if this is known behavior, but it looks like putting an expression in the "trigger_watch" fields breaks the circular fixation point stimulus - it outputs false into the trigger_flag variable no matter the value of the expression. It's not holding me up - as a workaround I created a dummy variable which gets updated whenever the independent variable in the expression gets updated.

I haven't tested the rectangular fixation point stimulus.


  1. Support Staff 1 Posted by Christopher Sta... on 01 Apr, 2016 02:30 PM

    Christopher Stawarz's Avatar

    Hi Evan,

    Yes, that is known behavior, and it applies to both fixation point types. Changes to the independent variable(s) don't cause the expression to be re-evaluated. Had you not already thought of that workaround, I would have suggested something similar.


  2. Christopher Stawarz closed this discussion on 04 Apr, 2016 03:09 PM.

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