Virtual Environment for Topographical Orientation (VETO): Clinical rationale and technical characteristics

The lack of spatial orientation often serves as a warning light for a diffu sed cerebral impairment, such as the one at the origin of a confusional sta te or of a mental disorder. Topographical orientation disorders may be the expression of memory or attention deficits, unilateral spatial negligence, or elementary visuoperceptive disorders. In a minority of cases, spatial di sorientation presents as an isolated disorder and is the expression of a fo cal brain lesion. The paper describes the clinical rationale and the technical characteristic s of the Virtual Environment for Topographical Orientation (VETO). VETO is used both as a complementary tool for the assessment of topographical orien tation disorders and to increase the possibilities of management of these p atients from a rehabilitative point of view. VETO is based on the recent theoretical model of wayfinding in virtual envi ronments proposed by Chen and Stanney (1999). This model suggests that wayf inders generally start from the direct perception of the environment or fro m the recall of a cognitive map. In terms of direct perception of the envir onment, landmark knowledge is acquired by directly viewing indirect represe ntation such as photographs. In terms of cognitive mapping, procedure/route knowledge is acquired through direct experience or through simulated exper ience and stored in memory. Our hypothesis is that the study of spatial orientation through specific VE TO tasks, both in normal samples and in subjects affected by topographical disorientation, can bring greater comprehension and validation of the cogni tive models of spatial orientation present in literature.