This study investigated whether brain neural activity that accompanied the processing of previously learned map information was influenced by the modality in which the spatial parameters of the maps were originally learned. Participants learned a map by either viewing it directly or by reading an equivalent verbal description. Following learning, the participants' ability to use their spatial knowledge was tested in a spatial orientation task. Electrophysiological recordings identified significant effects of prior learning modality on event-related brain activity within 300 ms following the presentation of map orientation instructions. The results indicate that modality-specificity in spatial memory is present at a very early stage of processing.