Cargando…

Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory

Previous work has demonstrated a distinction between maintenance of two types of spatial information in working memory (WM): spatial locations and spatial relations. While a body of work has investigated the neural mechanisms of sensory-based information like spatial locations, little is known about...

Descripción completa

Detalles Bibliográficos
Autores principales: Blacker, Kara J., Courtney, Susan M.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: Frontiers Media S.A. 2016
Materias:
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5121279/
https://www.ncbi.nlm.nih.gov/pubmed/27932963
http://dx.doi.org/10.3389/fnhum.2016.00594
_version_ 1782469378233597952
author Blacker, Kara J.
Courtney, Susan M.
author_facet Blacker, Kara J.
Courtney, Susan M.
author_sort Blacker, Kara J.
collection PubMed
description Previous work has demonstrated a distinction between maintenance of two types of spatial information in working memory (WM): spatial locations and spatial relations. While a body of work has investigated the neural mechanisms of sensory-based information like spatial locations, little is known about how spatial relations are maintained in WM. In two experiments, we used fMRI to investigate the involvement of early visual cortex in the maintenance of spatial relations in WM. In both experiments, we found less quadrant-specific BOLD activity in visual cortex when a single spatial relation, compared to a single spatial location, was held in WM. Also across both experiments, we found a consistent set of brain regions that were differentially activated during maintenance of locations vs. relations. Maintaining a location, compared to a relation, was associated with greater activity in typical spatial WM regions like posterior parietal cortex and prefrontal regions. Whereas maintaining a relation, compared to a location, was associated with greater activity in the parahippocampal gyrus and precuneus/retrosplenial cortex. Further, in Experiment 2 we manipulated WM load and included trials where participants had to maintain three spatial locations or relations. Under this high load condition, the regions sensitive to locations vs. relations were somewhat different than under low load. We also identified regions that were sensitive to load specifically for location or relation maintenance, as well as overlapping regions sensitive to load more generally. These results suggest that the neural substrates underlying WM maintenance of spatial locations and relations are distinct from one another and that the neural representations of these distinct types of spatial information change with load.
format Online
Article
Text
id pubmed-5121279
institution National Center for Biotechnology Information
language English
publishDate 2016
publisher Frontiers Media S.A.
record_format MEDLINE/PubMed
spelling pubmed-51212792016-12-08 Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory Blacker, Kara J. Courtney, Susan M. Front Hum Neurosci Neuroscience Previous work has demonstrated a distinction between maintenance of two types of spatial information in working memory (WM): spatial locations and spatial relations. While a body of work has investigated the neural mechanisms of sensory-based information like spatial locations, little is known about how spatial relations are maintained in WM. In two experiments, we used fMRI to investigate the involvement of early visual cortex in the maintenance of spatial relations in WM. In both experiments, we found less quadrant-specific BOLD activity in visual cortex when a single spatial relation, compared to a single spatial location, was held in WM. Also across both experiments, we found a consistent set of brain regions that were differentially activated during maintenance of locations vs. relations. Maintaining a location, compared to a relation, was associated with greater activity in typical spatial WM regions like posterior parietal cortex and prefrontal regions. Whereas maintaining a relation, compared to a location, was associated with greater activity in the parahippocampal gyrus and precuneus/retrosplenial cortex. Further, in Experiment 2 we manipulated WM load and included trials where participants had to maintain three spatial locations or relations. Under this high load condition, the regions sensitive to locations vs. relations were somewhat different than under low load. We also identified regions that were sensitive to load specifically for location or relation maintenance, as well as overlapping regions sensitive to load more generally. These results suggest that the neural substrates underlying WM maintenance of spatial locations and relations are distinct from one another and that the neural representations of these distinct types of spatial information change with load. Frontiers Media S.A. 2016-11-24 /pmc/articles/PMC5121279/ /pubmed/27932963 http://dx.doi.org/10.3389/fnhum.2016.00594 Text en Copyright © 2016 Blacker and Courtney. http://creativecommons.org/licenses/by/4.0/ This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
spellingShingle Neuroscience
Blacker, Kara J.
Courtney, Susan M.
Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory
title Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory
title_full Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory
title_fullStr Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory
title_full_unstemmed Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory
title_short Distinct Neural Substrates for Maintaining Locations and Spatial Relations in Working Memory
title_sort distinct neural substrates for maintaining locations and spatial relations in working memory
topic Neuroscience
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5121279/
https://www.ncbi.nlm.nih.gov/pubmed/27932963
http://dx.doi.org/10.3389/fnhum.2016.00594
work_keys_str_mv AT blackerkaraj distinctneuralsubstratesformaintaininglocationsandspatialrelationsinworkingmemory
AT courtneysusanm distinctneuralsubstratesformaintaininglocationsandspatialrelationsinworkingmemory