Long-lasting topographical disorientation in new environments.

We describe the case of a young woman with long-lasting topographical disorientation following a haemorrhagic lesion of the right temporo-occipital region involving the hippocampus. She was unable to orient herself in novel environments and to perform learning spatial tasks both in real-world settings and laboratory conditions. Her ability to recall and navigate through known routes as well as to recognize familiar landmarks was preserved. Neuropsychological evaluation revealed a mild long-term memory deficit. A similar neuropsychological and experimental pattern was observed 8 years later (at the time of follow-up) when she showed a persistent topographical disorientation and a slight worsening of verbal and visuo-spatial long-term memory disorders. Her topographical disorientation was characterized by an impairment confined to the anterograde memory domain, a not frequent pattern reported in literature, in the absence of remote topographical memory disorders. The presence of a lesion localized in the right occipito-temporal region and hippocampus combined with the results observed in some experimental tasks could also contribute to the debate of the role of neural correlates involved in topographical spatial knowledge.