Described herein are improved systems and methods for diagnosis and therapy of vision stability dysfunctions in a patient. One embodiment provides a device (1) for obtaining data from a patient (3). Device (1) includes a frame (5) configured for mounting to the patient (3), a target module (8) for providing a drive signal to define a selectively movable target object, an eye tracking module (12) mounted to the frame (5), the module (12) being responsive to the drive signal for obtaining first data indicative of one or more characteristics of the patients eyes and a head tracking module (16) mounted to the frame (5), the head tracking module (16) being responsive to the drive signal for obtaining second data indicative of one or more characteristics of the motion of the patients head.
