Participants who are subjected to all of the experimental procedures except the experimental manipulation are called

They are called CONTROLS.

Control in an experiment can be defined as an entity that remains the same throughout the experiment. A control in an experiment must remain the same in order to get accurate result. This is done by comparing the results of the experiment with the control.

Controls are used in experiment where some not so obvious factors that might affect the experiment significantly might be present.

i need more info !

answer; you can turn right on a red signal (when posted);