Perception of Impossible Scenes Reveals Differential Hippocampal and Parahippocampal Place Area Contributions to Spatial Coherency

Hippocampus ◽  
2016 ◽  
Vol 27 (1) ◽  
pp. 61-76 ◽  
Author(s):  
Danielle Douglas ◽  
Sathesan Thavabalasingam ◽  
Zahraa Chorghay ◽  
Edward B. O'Neil ◽  
Morgan D. Barense ◽  
...  
Keyword(s):  
Parahippocampal Place Area ◽  
Spatial Coherency

The Effect of Attention on Repetition Suppression and Multivoxel Pattern Similarity

2013 ◽  
Vol 25 (8) ◽  
pp. 1305-1314 ◽  
Author(s):  
Katherine S. Moore ◽  
Do-Joon Yi ◽  
Marvin Chun
Keyword(s):  
Task Demands ◽  
Initial Presentation ◽  
Fmri Signal ◽  
Repetition Suppression ◽  
Specific Memory ◽  
Pattern Similarity ◽  
Parahippocampal Place Area ◽  
And Task

Fundamental to our understanding of learning is the role of attention. We investigated how attention affects two fMRI measures of stimulus-specific memory: repetition suppression (RS) and pattern similarity (PS). RS refers to the decreased fMRI signal when a stimulus is repeated, and it is sensitive to manipulations of attention and task demands. In PS, region-wide voxel-level patterns of responses are evaluated for their similarity across repeated presentations of a stimulus. More similarity across presentations is related to better learning, but the role of attention on PS is not known. Here, we directly compared these measures during the visual repetition of scenes while manipulating attention. Consistent with previous findings, we observed RS in the scene-sensitive parahippocampal place area only when a scene was attended both at initial presentation and upon repetition in subsequent trials, indicating that attention is important for RS. Likewise, we observed greater PS in response to repeated pairs of scenes when both instances of the scene were attended than when either or both were ignored. However, RS and PS did not correlate on either a scene-by-scene or subject-by-subject basis, and PS measures revealed above-chance similarity even when stimuli were ignored. Thus, attention has different effects on RS and PS measures of perceptual repetition.

scholarly journals Neural differentiation is moderated by age in scene- but not face-selective cortical regions

2020 ◽  
Author(s):  
Sabina Srokova ◽  
Paul F. Hill ◽  
Joshua D. Koen ◽  
Danielle R. King ◽  
Michael D. Rugg
Keyword(s):  
Cognitive Aging ◽  
Neural Differentiation ◽  
Memory Performance ◽  
Retrosplenial Cortex ◽  
Stimulus Category ◽  
Age Related ◽  
Pattern Similarity ◽  
Cortical Regions ◽  
Neural Selectivity ◽  
Parahippocampal Place Area

AbstractThe aging brain is characterized by neural dedifferentiation – an apparent decrease in the functional selectivity of category-selective cortical regions. Age-related reductions in neural differentiation have been proposed to play a causal role in cognitive aging. Recent findings suggest, however, that age-related dedifferentiation is not equally evident for all stimulus categories and, additionally, that the relationship between neural differentiation and cognitive performance is not moderated by age. In light of these findings, in the present experiment younger and older human adults (males and females) underwent fMRI as they studied words paired with images of scenes or faces prior to a subsequent memory task. Neural selectivity was measured in two scene-selective (parahippocampal place area and retrosplenial cortex) and two face-selective (fusiform and occipital face areas) regions of interest using both a univariate differentiation index and multivoxel pattern similarity analysis. Both methods provided highly convergent results which revealed evidence of age-related reductions in neural dedifferentiation in scene-selective but not face-selective cortical regions. Additionally, neural differentiation in the parahippocampal place area demonstrated a positive, age-invariant relationship with subsequent source memory performance (recall of the image category paired with each recognized test word). These findings extend prior findings suggesting that age-related neural dedifferentiation is not a ubiquitous phenomenon, and that the specificity of neural responses to scenes is predictive subsequent memory performance independently of age.Significance StatementIncreasing age is associated with reduced neural specificity in cortical regions that are selectively responsive to a given perceptual stimulus category (age-related neural dedifferentiation), a phenomenon which has been proposed to contribute to cognitive aging. Recent findings reveal that age-related neural dedifferentiation is not present for all types of visual stimulus categories, and the factors which determine when the phenomenon arises remain unclear. Here, we demonstrate that scene- but not face-selective cortical regions exhibit age-related neural dedifferentiation during an attentionally-demanding task. Additionally, we report that higher neural selectivity in the scene-selective ‘parahippocampal place area’ is associated with better memory performance after controlling for variance associated with age group, adding to evidence that neural differentiation impacts cognition across the adult lifespan.

scholarly journals Behavioral and Neuroimaging Evidence for a Contribution of Color and Texture Information to Scene Classification in a Patient with Visual Form Agnosia

2004 ◽  
Vol 16 (6) ◽  
pp. 955-965 ◽  
Author(s):  
Jennifer K. E. Steeves ◽  
G. Keith Humphrey ◽  
Jody C. Culham ◽  
Ravi S. Menon ◽  
A. David Milner ◽  
...  
Keyword(s):  
Scene Perception ◽  
Object Perception ◽  
Visual Texture ◽  
Visual Form ◽  
Black And White ◽  
Form Vision ◽  
Common Notion ◽  
Vision Deficits ◽  
Behavioral Evidence ◽  
Parahippocampal Place Area

A common notion is that object perception is a necessary precursor to scene perception. Behavioral evidence suggests, however, that scene perception can operate independently of object perception. Further, neuroimaging has revealed a specialized human cortical area for viewing scenes that is anatomically distinct from areas activated by viewing objects. Here we show that an individual with visual form agnosia, D.F., who has a profound deficit in object recognition but spared color and visual texture perception, could still classify scenes and that she was fastest when the scenes were presented in the appropriate color. When scenes were presented as black-and-white images, she made a large number of errors in classification. Functional magnetic resonance imaging revealed selective activation in the parahippocampal place area (PPA) when D.F. viewed scenes. Unlike control observers, D.F. demonstrated higher activation in the PPA for scenes presented in the appropriate color than for black-and-white versions. The results demonstrate that an individual with profound form vision deficits can still use visual texture and color to classify scenes—and that this intact ability is reflected in differential activation of the PPA with colored versions of scenes.

scholarly journals Obtaining free USArray data by multi-dimensional seismic reconstruction

2019 ◽  
Vol 10 (1) ◽  
Author(s):  
Yangkang Chen ◽  
Min Bai ◽  
Yunfeng Chen
Keyword(s):  
Incomplete Data ◽  
Reduction Method ◽  
Three Dimensional ◽  
Noisy Data ◽  
Rank Reduction ◽  
Uniform Sampling ◽  
Structure And Dynamics ◽  
Seismic Wavefield ◽  
Suppress Noise ◽  
Spatial Coherency

Abstract USArray, a pioneering project for the dense acquisition of earthquake data, provides a semi-uniform sampling of the seismic wavefield beneath its footprint and greatly advances the understanding of the structure and dynamics of Earth. Despite continuing efforts in improving the acquisition design, network irregularity still causes spatial sampling alias and incomplete, noisy data, which imposes major challenges in array-based data analysis and seismic imaging. Here we employ an iterative rank-reduction method to simultaneously reconstruct the missing traces and suppress noise, i.e., obtaining free USArray recordings as well as enhancing the existing data. This method exploits the spatial coherency of three-dimensional data and recovers the missing elements via the principal components of the incomplete data. We examine its merits using simulated and real teleseismic earthquake recordings. The reconstructed P wavefield enhances the spatial coherency and accuracy of tomographic travel time measurements, which demonstrates great potential to benefit seismic investigations based on array techniques.

Mnemonic functions of the parahippocampal place area: An event related fMRI study

NeuroImage ◽  
2001 ◽  
Vol 13 (6) ◽  
pp. 663
Author(s):  
Russell Epstein ◽  
Nancy Kanwisher
Keyword(s):  
Fmri Study ◽  
Parahippocampal Place Area

Differential contributions of the parahippocampal place area and the anterior hippocampus to human memory for scenes

Hippocampus ◽  
2002 ◽  
Vol 12 (6) ◽  
pp. 718-723 ◽  
Author(s):  
Stefan Köhler ◽  
Joelle Crane ◽  
Brenda Milner
Keyword(s):  
Human Memory ◽  
Parahippocampal Place Area
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