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Overlapping functional anatomy for working memory and visual search.

Anderson EJ, Mannan SK, Rees G, Sumner P, Kennard C - Exp Brain Res (2010)

Bottom Line: Using visually matched spatial and non-spatial working memory tasks, we confirmed previous behavioural findings that show significant dual-task interference effects occur when inefficient visual search is performed concurrently with either working memory task.Drawing on previous findings (Anderson et al. in Exp Brain Res 180:289-302, 2007), we propose that the most likely anatomical locus for these interference effects is the inferior and middle frontal cortex of the right hemisphere.These areas are associated with attentional selection from memory as well as manipulation of information in memory, and we propose that the visual search and working memory tasks used here compete for common processing resources underlying these mechanisms.

View Article: PubMed Central - PubMed

Affiliation: Department of Clinical Neuroscience, Imperial College London, Charing Cross Hospital, St. Dunstan's Road, London W6 8RP, UK. e.anderson@fil.ion.ucl.ac.uk

ABSTRACT
Recent behavioural findings using dual-task paradigms demonstrate the importance of both spatial and non-spatial working memory processes in inefficient visual search (Anderson et al. in Exp Psychol 55:301-312, 2008). Here, using functional magnetic resonance imaging (fMRI), we sought to determine whether brain areas recruited during visual search are also involved in working memory. Using visually matched spatial and non-spatial working memory tasks, we confirmed previous behavioural findings that show significant dual-task interference effects occur when inefficient visual search is performed concurrently with either working memory task. Furthermore, we find considerable overlap in the cortical network activated by inefficient search and both working memory tasks. Our findings suggest that the interference effects observed behaviourally may have arisen from competition for cortical processes subserved by these overlapping regions. Drawing on previous findings (Anderson et al. in Exp Brain Res 180:289-302, 2007), we propose that the most likely anatomical locus for these interference effects is the inferior and middle frontal cortex of the right hemisphere. These areas are associated with attentional selection from memory as well as manipulation of information in memory, and we propose that the visual search and working memory tasks used here compete for common processing resources underlying these mechanisms.

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Region of interest analyses in R MFG and R IFG. Sagittal, coronal and axial views of the right IFG ROI (a) and right MFG ROI (b). These regions were defined apriori using the results of our previous fMRI study on inefficient search (Anderson et al. 2007). The right IFG region was defined by a cluster of activity centered around the MNI coordinates [44/20/-6] (see “Methods”). The right MFG region was defined by a sphere with a 15 mm radius centered on the MNI coordinates [48/12/26]. The bar graphs represent parameter estimates for spatial (blue) and verbal (green) working memory, for single and dual-task conditions, within these two regions. Error bars indicate the SE of the mean for the group
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Fig6: Region of interest analyses in R MFG and R IFG. Sagittal, coronal and axial views of the right IFG ROI (a) and right MFG ROI (b). These regions were defined apriori using the results of our previous fMRI study on inefficient search (Anderson et al. 2007). The right IFG region was defined by a cluster of activity centered around the MNI coordinates [44/20/-6] (see “Methods”). The right MFG region was defined by a sphere with a 15 mm radius centered on the MNI coordinates [48/12/26]. The bar graphs represent parameter estimates for spatial (blue) and verbal (green) working memory, for single and dual-task conditions, within these two regions. Error bars indicate the SE of the mean for the group

Mentions: To investigate the neural correlates of dual-task performance, we compared activity during dual-task and single-task conditions within two specific regions of frontal cortex which we predicted to be the most likely site of the dual-task interference found between the inefficient search and working memory tasks used here (Fig. 6).Fig. 6


Overlapping functional anatomy for working memory and visual search.

Anderson EJ, Mannan SK, Rees G, Sumner P, Kennard C - Exp Brain Res (2010)

Region of interest analyses in R MFG and R IFG. Sagittal, coronal and axial views of the right IFG ROI (a) and right MFG ROI (b). These regions were defined apriori using the results of our previous fMRI study on inefficient search (Anderson et al. 2007). The right IFG region was defined by a cluster of activity centered around the MNI coordinates [44/20/-6] (see “Methods”). The right MFG region was defined by a sphere with a 15 mm radius centered on the MNI coordinates [48/12/26]. The bar graphs represent parameter estimates for spatial (blue) and verbal (green) working memory, for single and dual-task conditions, within these two regions. Error bars indicate the SE of the mean for the group
© Copyright Policy
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC2800858&req=5

Fig6: Region of interest analyses in R MFG and R IFG. Sagittal, coronal and axial views of the right IFG ROI (a) and right MFG ROI (b). These regions were defined apriori using the results of our previous fMRI study on inefficient search (Anderson et al. 2007). The right IFG region was defined by a cluster of activity centered around the MNI coordinates [44/20/-6] (see “Methods”). The right MFG region was defined by a sphere with a 15 mm radius centered on the MNI coordinates [48/12/26]. The bar graphs represent parameter estimates for spatial (blue) and verbal (green) working memory, for single and dual-task conditions, within these two regions. Error bars indicate the SE of the mean for the group
Mentions: To investigate the neural correlates of dual-task performance, we compared activity during dual-task and single-task conditions within two specific regions of frontal cortex which we predicted to be the most likely site of the dual-task interference found between the inefficient search and working memory tasks used here (Fig. 6).Fig. 6

Bottom Line: Using visually matched spatial and non-spatial working memory tasks, we confirmed previous behavioural findings that show significant dual-task interference effects occur when inefficient visual search is performed concurrently with either working memory task.Drawing on previous findings (Anderson et al. in Exp Brain Res 180:289-302, 2007), we propose that the most likely anatomical locus for these interference effects is the inferior and middle frontal cortex of the right hemisphere.These areas are associated with attentional selection from memory as well as manipulation of information in memory, and we propose that the visual search and working memory tasks used here compete for common processing resources underlying these mechanisms.

View Article: PubMed Central - PubMed

Affiliation: Department of Clinical Neuroscience, Imperial College London, Charing Cross Hospital, St. Dunstan's Road, London W6 8RP, UK. e.anderson@fil.ion.ucl.ac.uk

ABSTRACT
Recent behavioural findings using dual-task paradigms demonstrate the importance of both spatial and non-spatial working memory processes in inefficient visual search (Anderson et al. in Exp Psychol 55:301-312, 2008). Here, using functional magnetic resonance imaging (fMRI), we sought to determine whether brain areas recruited during visual search are also involved in working memory. Using visually matched spatial and non-spatial working memory tasks, we confirmed previous behavioural findings that show significant dual-task interference effects occur when inefficient visual search is performed concurrently with either working memory task. Furthermore, we find considerable overlap in the cortical network activated by inefficient search and both working memory tasks. Our findings suggest that the interference effects observed behaviourally may have arisen from competition for cortical processes subserved by these overlapping regions. Drawing on previous findings (Anderson et al. in Exp Brain Res 180:289-302, 2007), we propose that the most likely anatomical locus for these interference effects is the inferior and middle frontal cortex of the right hemisphere. These areas are associated with attentional selection from memory as well as manipulation of information in memory, and we propose that the visual search and working memory tasks used here compete for common processing resources underlying these mechanisms.

Show MeSH