Anterograde memory for visuospatial arrays

A new test was developed to assess direction of errors and hemispatial differences in anterograde memory for visuospatial arrays of abstract figures. After a series of learning trials, delayed recall of figure placement was obtained in 12 healthy dextral adults. Horizontal and vertical errors were measured for each figure. Mean directional error and mean absolute error were calculated for each subject in left and right hemispace for horizontal and vertical dimensions. Although no hemispatial effect was found for mean absolute error, hemispatial differences were present for mean directional error in both horizontal and vertical dimensions. Overall, horizontal deviations were medial, and vertical deviations were downward. However, these effects reached statistical significance only in right hemispace. The directional errors are believed to be due to an attentional shift toward proximal peripersonal space, in combination with attentional shifts from differential left/right cerebral activation.