Support for distinct subcomponents of spatial working memory: A double dissociation between spatial–simultaneous and spatial–sequential performance in unilateral neglect

Abstract

Over the last decade, many studies have demonstrated that visuospatial working memory (VSWM) can be divided into separate subsystems dedicated to the retention of visual patterns and their serial order. Impaired VSWM has been suggested to exacerbate left visual neglect in right-brain-damaged individuals. The aim of this study was to investigate the segregation between spatial–sequential and spatial–simultaneous working memory in individuals with neglect. We demonstrated that patterns of results on these VSWM tasks can be dissociated. Spatial–simultaneous and sequential aspects of VSWM can be selectively impaired in unilateral neglect. Our results support the hypothesis of multiple VSWM subsystems, which should be taken into account to better understand neglect-related deficits.

Keywords:

• unilateral neglect
• visuospatial working memory
• spatial cognition

Notes

1. Each of these five neglect participants is compared to a specific control group matched for age and educational level.

2. The number of omissions on the simultaneous task was strictly the same on the left (32%) and the right (32%) sides. In addition, P9 showed no sign of visual extinction in the finger confrontation test (Azouvi et al., 2002).