Neuropsychological evidence for a spatial bias in visual short-term memory after left posterior ventral damage

Abstract

For the first time, we report a spatial bias in visual short-term memory (VSTM) after left medial and inferior occipito-temporal damage. Our patient D.M. showed a spatial bias in report from VSTM, being more accurate at reporting stimuli presented in her left than her right visual field (Experiment 1). This spatial bias could not be attributed to a visual field deficit (Experiment 2) and was based on the relative rather than the absolute locations of the stimuli (Experiment 3). It was reduced when the transfer of items to VSTM was facilitated—for example, by grouping stimuli (Experiment 4) or by reducing the number of items to be remembered (Experiment 5). The spatial bias was attenuated when items moved from right to centre or left to centre, and D.M. was cued to report the item that would have been on the right or left, had the movement continued (Experiment 6). We conclude that posterior ventral damage can impair both the consolidation of new information in VSTM and the explicit report of consolidated information from VSTM.