Purchase this article with an account.
Nader Noori, Laurent Itti; Selective Impact of Mental Abstract Tasks on Visuospatial Short-Term Memory. Journal of Vision 2012;12(9):293. doi: https://doi.org/10.1167/12.9.293.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Recent findings of neuroimaging and neuropsychological studies suggest that brain regions with visual-spatial characteristics are involved in a wide range of working memory tasks that require memory manipulation (Olson and Berryhill 2009). The spatial registry hypothesis (Noori and Itti 2011) provides an account for these findings by assuming a functional role for brain regions with visual-spatial encoding features in registering task-relevant working memory items in a spatially-organized short-term memory. These spatial registries may then be used as a reference to the items of the working memory for selective processing through shifting the spatial attention towards the registry locations. This hypothesis predicts that the impact of a secondary executive working memory task on the visuospatial short-term memory is selective to regions of the space that are being used for the corresponding registry process. We test this prediction by investigating the impact of the mental sorting of four characters on the visuospatial short-term memory of visual targets along horizontal and vertical directions. Our results show that when the working memory is engaged in the maintaining of four characters, the error rate in recalling horizontally spanned targets is significantly lower than vertically spanned targets (respectively 20.7%(M) +/- 2.4%(SEM) and 30.7%(M) +/- 3.7%(SEM) (ttest;n=15,p<0.0202)). However when subjects rearrange those characters in an ascending order, the error rate for horizontal targets significantly increases to 33.2%(M) +/- 2.8%(SEM) (ttest;n=15,p<0.00097) while the error rate for vertically spanned targets does not show a significant change (ttest;n=15,p>0.53). In a control experiment subjects are assigned a double counting task concurrent with retaining locations of two targets located on a circle. Doubling the signal rate for the mental task did not affect the error rates in recalling the location of the visual targets. This finding suggests that the observed impact might not be associate to deferring potential rehearsing process in the visuospatial short-term memory.
Meeting abstract presented at VSS 2012
This PDF is available to Subscribers Only