Spatial Orientation and Spatial Memory Within a 'Locomotor Maze' for Humans

Spatial behavior was investigated using a locomotor maze for humans which incorporates basic features of widely used animal paradigms. Experiments are based on the 'cognitive map' theory originally put forward by O'Keefe & Nadel [22] and allowed the assessment of place learning, and spatial working and spatial reference memory errors. In our procedure, subjects and patients have to learn and remember five out of twenty locations within a 4 × 5 m area with completely controlled intra- and extramaze cue conditions. Usually, participants learned to reach the criterion. A probe trial from an opposite starting position with transposed intramaze cues followed. Results showed that it is possible to assess cuedependent orientation, to dissociate spatial working memory and spatial reference memory and to identify 'place-behavior' using specific parameters derived from inertial navigation theory [16]. This will be demonstrated in selected cases with circumscribed cerebral lesions and in unimpaired subjects.