Output Form-Fields to Bean

hello there

I have an User Task with some form fields. When the user complete the task, corresponding values appears as process instance variables. It is possible to fill default value from some existing bean like this ${myObject.myfiled}.

Is it possible instead of creating variable to inject form output value in the already existing object, i.e. back into ${myObject.myfiled}? I did not find any solution so far. Any ideas?