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Papers by Jack Ryan
The Journal of neuroscience : the official journal of the Society for Neuroscience, Jan 4, 2015
The use of landmarks is central to many navigational strategies. Here we use multivoxel pattern a... more The use of landmarks is central to many navigational strategies. Here we use multivoxel pattern analysis of fMRI data to understand how landmarks are coded in the human brain. Subjects were scanned while viewing the interiors and exteriors of campus buildings. Despite their visual dissimilarity, interiors and exteriors corresponding to the same building elicited similar activity patterns in the parahippocampal place area (PPA), retrosplenial complex (RSC), and occipital place area (OPA), three regions known to respond strongly to scenes and buildings. Generalization across stimuli depended on knowing the correspondences among them in the PPA but not in the other two regions, suggesting that the PPA is the key region involved in learning the different perceptual instantiations of a landmark. In contrast, generalization depended on the ability to freely retrieve information from memory in RSC, and it did not depend on familiarity or cognitive task in OPA. Together, these results sugge...
Journal of Vision, 2015
Highlights d TMS to the OPA impairs accuracy of navigation to locations in a virtual arena d This... more Highlights d TMS to the OPA impairs accuracy of navigation to locations in a virtual arena d This impairment is observed for locations defined by distance to a bounding wall d This impairment is not found for locations defined by landmarks or visual markings d Results causally implicate OPA in the perception of environmental boundaries
Nature Neuroscience, 2015
In the version of this article initially published, there were quotation marks around "encoded" i... more In the version of this article initially published, there were quotation marks around "encoded" in the first paragraph and around "encode" in the last paragraph of the main text; these have been deleted. The second sentence of the third paragraph read "habituated in a stimulus-selective manner in V1 as SRP developed"; "in V1" has been deleted. The Figure 7d legend began "Failure of SRP induction"; the correct text is "Selective failure of SRP expression. " The sixth paragraph of the Discussion began "Behavioral manifestation of the vidget required V1"; the correct text is "Behavioral expression of the vidget requires V1. " The eighth paragraph of the Discussion included "first, a 'response' pathway that directly mediates the vidget and does not undergo long-term modification, and second, a 'learning' pathway"; "first, " and "second, " have been deleted. The errors have been corrected in the HTML and PDF versions of the article.
Nature Neuroscience, 2014
The neural systems that code for location and facing direction during spatial navigation have bee... more The neural systems that code for location and facing direction during spatial navigation have been extensively investigated; however, the mechanisms by which these quantities are referenced to external features of the world are not well understood. To address this issue, we examined behavioral priming and fMRI activity patterns while human subjects re-instantiated spatial views from a recently learned virtual environment. Behavioral results indicated that imagined location and facing direction were represented during this task, and multi-voxel pattern analyses indicated the retrosplenial complex (RSC) was the anatomical locus of these spatial codes. Critically, in both cases, location and direction were defined based on fixed elements of the local environment and generalized across geometrically-similar local environments. These results suggest that RSC anchors internal spatial representations to local topographical features, thus allowing us to stay oriented while we navigate and to retrieve from memory the experience of being in a particular place. Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:
The Journal of neuroscience : the official journal of the Society for Neuroscience, Jan 4, 2015
The use of landmarks is central to many navigational strategies. Here we use multivoxel pattern a... more The use of landmarks is central to many navigational strategies. Here we use multivoxel pattern analysis of fMRI data to understand how landmarks are coded in the human brain. Subjects were scanned while viewing the interiors and exteriors of campus buildings. Despite their visual dissimilarity, interiors and exteriors corresponding to the same building elicited similar activity patterns in the parahippocampal place area (PPA), retrosplenial complex (RSC), and occipital place area (OPA), three regions known to respond strongly to scenes and buildings. Generalization across stimuli depended on knowing the correspondences among them in the PPA but not in the other two regions, suggesting that the PPA is the key region involved in learning the different perceptual instantiations of a landmark. In contrast, generalization depended on the ability to freely retrieve information from memory in RSC, and it did not depend on familiarity or cognitive task in OPA. Together, these results sugge...
Journal of Vision, 2015
Highlights d TMS to the OPA impairs accuracy of navigation to locations in a virtual arena d This... more Highlights d TMS to the OPA impairs accuracy of navigation to locations in a virtual arena d This impairment is observed for locations defined by distance to a bounding wall d This impairment is not found for locations defined by landmarks or visual markings d Results causally implicate OPA in the perception of environmental boundaries
Nature Neuroscience, 2015
In the version of this article initially published, there were quotation marks around "encoded" i... more In the version of this article initially published, there were quotation marks around "encoded" in the first paragraph and around "encode" in the last paragraph of the main text; these have been deleted. The second sentence of the third paragraph read "habituated in a stimulus-selective manner in V1 as SRP developed"; "in V1" has been deleted. The Figure 7d legend began "Failure of SRP induction"; the correct text is "Selective failure of SRP expression. " The sixth paragraph of the Discussion began "Behavioral manifestation of the vidget required V1"; the correct text is "Behavioral expression of the vidget requires V1. " The eighth paragraph of the Discussion included "first, a 'response' pathway that directly mediates the vidget and does not undergo long-term modification, and second, a 'learning' pathway"; "first, " and "second, " have been deleted. The errors have been corrected in the HTML and PDF versions of the article.
Nature Neuroscience, 2014
The neural systems that code for location and facing direction during spatial navigation have bee... more The neural systems that code for location and facing direction during spatial navigation have been extensively investigated; however, the mechanisms by which these quantities are referenced to external features of the world are not well understood. To address this issue, we examined behavioral priming and fMRI activity patterns while human subjects re-instantiated spatial views from a recently learned virtual environment. Behavioral results indicated that imagined location and facing direction were represented during this task, and multi-voxel pattern analyses indicated the retrosplenial complex (RSC) was the anatomical locus of these spatial codes. Critically, in both cases, location and direction were defined based on fixed elements of the local environment and generalized across geometrically-similar local environments. These results suggest that RSC anchors internal spatial representations to local topographical features, thus allowing us to stay oriented while we navigate and to retrieve from memory the experience of being in a particular place. Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use: