DEPTH-PERCEPTION IN LAPAROSCOPY THROUGH PERCEPTION-ACTION COUPLING

Laparoscopic surgery has considerable advantages for the patient over conventional surgery; for the surgeon, however, it has mostly disadvan tages. One of the main problems is that the coupling between action an d perception is hampered, i.e, the surgeon has no direct control over the laparoscope since it is held and directed by an assistant. In two experiments we explored how action-perception coupling can be restored . In the first experiment we explored the possibility of restoring act ion-perception coupling by providing the surgeon with direct control o ver his visual information. The applicability of two principles were e xplored: viewpoint movement parallax, where the surgeon controls the c hange in the point of observation (the laparoscope) directly with his head movement; and shadow movement parallax, where the surgeon control s the change in the point of illumination directly with his head movem ents. In a second experiment we investigated whether the performance o f a surgeon is influenced by motions of the laparoscope that are not g enerated by the surgeon himself, but by the assistant directing the la paroscope. We concluded that restoring the action-perception coupling (i.e. providing the surgeon with direct control over the laparoscope's motions) improves the surgeon's ability to perform explorative, as we ll as manipulative, tasks. We also concluded that, as disturbances of laparoscope movements hamper the surgeon during manipulation, the lapa roscope should be supported by a mechanical support.