A computer-implemented method, system, and computer program product where a processor(s) displays, at a first location in an interface of a computing device, image(s) comprising a fixation point. The processor(s) obtains, from an eye tracking device, a first indication that a user whose eye movement is being tracked has at least one eye focused on the fixation point. The processor(s) renders, at a second location in the interface, a visual stimulus to stimulate a predefined location in a retina of the at least one eye. The processor(s) obtains, from the eye tracking device, a second indication that a user does not have the at least one eye focused on the fixation point. The processor(s) identifies a third location, a focal point of the user. The processor(s) reorients the image(s) such that the fixation point is at the third location and the stimulus is moved relative to the fixation point.
