Article

Increasing evidence suggests that working memory and perceptual processes are dynamically interrelated
due to modulating activity in overlapping brain networks. However, the direct influence of working
memoryon the spatio-temporal brain dynamics of behaviorally relevant intervening information remains
unclear. To investigate this issue, subjects performed a visual proximity grid perception task under three
different visual­spatial working memory (VSWM) load conditions. VSWM load was manipulated by asking
subjects to memorize the spatial locations of 6 or 3 disks. The grid was always presented between
the encoding and recognition of the disk pattern. As a baseline condition, grid stimuli were presented
without a VSWM context. VSWM load altered both perceptual performance and neural networks active
during intervening grid encoding. Participants performed faster and more accurately on a challenging
perceptual task under high VSWM load as compared to the low load and the baseline condition. Visual
evoked potential (VEP) analyses identified changes in the configuration of the underlying sources in one
particular period occurring 160­190mspost-stimulus onset. Source analyses further showed an occipitoparietal
down-regulation concurrent to the increased involvement of temporal and frontal resources in
the high VSWM context. Together, these data suggest that cognitive control mechanisms supporting
working memory may selectively enhance concurrent visual processing related to an independent goal.
More broadly, our findings are in line with theoretical models implicating the engagement of frontal
regions in synchronizing and optimizing mnemonic and perceptual resources towards multiple goals.

Langue : ANGLAIS