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Lesions to the right parietal regions of the brain cause difficulties in visual attention, spatial representation and orientation, imagery production and memory. Map reading, transformation of visual arrays, navigation around an unfamiliar space are just some of the many tasks which are beyond the spatially impaired brain. Suffers display the phenomena of neglecting the left half of their surrounding space and the inability to recognise even familiar objects viewed from unusual perspectives. As a result of extensive study in this field it has been firmly established that the right hemisphere and in particular the parietal lobe are concerned with spatial activity. Other areas of the human brain which are called upon during spatial tasks include the frontal lobes which are considered as crucial for remembering a spatial location.
Spatial short-term memory pinpointed in human brain:
circuits in the frontal cortex specialised for spatial working memory and eye movement
In a region in the middle of the frontal cortex (Brodmann's area 46 in the illustration), scientists hypothesised that they would find the human spatial working memory circuits (just in front of an area specialised for controlling eye movements (frontal eye field). They knew from brain imaging studies that this circuitry had evolved into a higher and more rearward location in the human frontal cortex. A region in the lower left frontal cortex (area 47 in the illustration) showed sustained activation during pauses in working memory tasks, thus clearly differentiating itself from the spatial working memory area. The discovery ends a search that had puzzled neuroscientists for most of the past decade.
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