scholarly journals Functional topography of the human entorhinal cortex

eLife ◽  
2015 ◽  
Vol 4 ◽  
Author(s):  
Tobias Navarro Schröder ◽  
Koen V Haak ◽  
Nestor I Zaragoza Jimenez ◽  
Christian F Beckmann ◽  
Christian F Doeller
Keyword(s):  
Entorhinal Cortex ◽  
Spatial Information ◽  
Spatial Navigation ◽  
Data Driven ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Human Homologue ◽  
Related Disease ◽  
Functional Topography

Despite extensive research on the role of the rodent medial and lateral entorhinal cortex (MEC/LEC) in spatial navigation, memory and related disease, their human homologues remain elusive. Here, we combine high-field functional magnetic resonance imaging at 7 T with novel data-driven and model-based analyses to identify corresponding subregions in humans based on the well-known global connectivity fingerprints in rodents and sensitivity to spatial and non-spatial information. We provide evidence for a functional division primarily along the anteroposterior axis. Localising the human homologue of the rodent MEC and LEC has important implications for translating studies on the hippocampo-entorhinal memory system from rodents to humans.

scholarly journals Integrating additional knowledge into the estimation of graphical models

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Yunqi Bu ◽  
Johannes Lederer
Keyword(s):  
Graphical Models ◽  
Tuning Parameter ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Graphical Modeling ◽  
Standard Methods ◽  
Neighborhood Selection ◽  
Selection For ◽  
The Brain

Abstract Graphical models such as brain connectomes derived from functional magnetic resonance imaging (fMRI) data are considered a prime gateway to understanding network-type processes. We show, however, that standard methods for graphical modeling can fail to provide accurate graph recovery even with optimal tuning and large sample sizes. We attempt to solve this problem by leveraging information that is often readily available in practice but neglected, such as the spatial positions of the measurements. This information is incorporated into the tuning parameter of neighborhood selection, for example, in the form of pairwise distances. Our approach is computationally convenient and efficient, carries a clear Bayesian interpretation, and improves standard methods in terms of statistical stability. Applied to data about Alzheimer’s disease, our approach allows us to highlight the central role of lobes in the connectivity structure of the brain and to identify an increased connectivity within the cerebellum for Alzheimer’s patients compared to other subjects.

scholarly journals Adaptive brain activity changes during tongue movement with palatal coverage from fMRI data

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yuka Inamochi ◽  
Kenji Fueki ◽  
Nobuo Usui ◽  
Masato Taira ◽  
Noriyuki Wakabayashi
Keyword(s):  
Spatial Information ◽  
Brain Activity ◽  
Motor Impairment ◽  
Angular Gyrus ◽  
Tongue Movement ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Oral Environment ◽  
Motor Dexterity ◽  
The Brain

AbstractSuccessful adaptation to wearing dentures with palatal coverage may be associated with cortical activity changes related to tongue motor control. The purpose was to investigate the brain activity changes during tongue movement in response to a new oral environment. Twenty-eight fully dentate subjects (mean age: 28.6-years-old) who had no experience with removable dentures wore experimental palatal plates for 7 days. We measured tongue motor dexterity, difficulty with tongue movement, and brain activity using functional magnetic resonance imaging during tongue movement at pre-insertion (Day 0), as well as immediately (Day 1), 3 days (Day 3), and 7 days (Day 7) post-insertion. Difficulty with tongue movement was significantly higher on Day 1 than on Days 0, 3, and 7. In the subtraction analysis of brain activity across each day, activations in the angular gyrus and right precuneus on Day 1 were significantly higher than on Day 7. Tongue motor impairment induced activation of the angular gyrus, which was associated with monitoring of the tongue’s spatial information, as well as the activation of the precuneus, which was associated with constructing the tongue motor imagery. As the tongue regained the smoothness in its motor functions, the activation of the angular gyrus and precuneus decreased.

Management Accountants’ Empathy and Their Violation of Fiduciary Duties: a Replication and Extension Study Using fMRI

2021 ◽  
Author(s):  
Sergeja Slapničar ◽  
Mina Ličen ◽  
Frank G. H. Hartmann ◽  
Anka Slana Ozimič ◽  
Grega Repovš
Keyword(s):  
Brain Activity ◽  
Cognitive Empathy ◽  
Affective Empathy ◽  
Business Unit ◽  
Personal Interest ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Management Accountants ◽  
Personal Interests

Research shows that management accountants’ role to support business unit managers’ decision-making may cause them to succumb to managers’ pressures to misreport. Using electroencephalographic (EEG) evidence, Eskenazi, Hartmann and Rietdijk (2016) demonstrate the role of automatic emotional mimicry, which drives misreporting when managers’ personal interest is at stake, but not when BU interest is at stake. In this study, we aim to replicate this finding using functional magnetic resonance imaging (fMRI), which enables us to separate affective from cognitive empathy. Thirty accounting professionals completed an emotion observation task during which empathy-related brain activity was recorded. We then explored accountants’ inclination to misreport using empathy-invoking accounting scenarios. We find that the inclination to misreport correlates with activation of cognitive empathy regions, but only for scenarios in which accountants misreport to serve business unit’s interests, rather than managers’ personal interests. We find no evidence for a role of affective empathy.

scholarly journals Lateral entorhinal cortex lesions impair both egocentric and allocentric object–place associations

2020 ◽  
Vol 4 ◽  
pp. 239821282093946
Author(s):  
Maneesh V. Kuruvilla ◽  
David I. G. Wilson ◽  
James A. Ainge
Keyword(s):  
Entorhinal Cortex ◽  
Reference Frames ◽  
Spatial Information ◽  
Unit Recording ◽  
Egocentric Reference Frame ◽  
Spatial Frames Of Reference ◽  
Significant Difference ◽  
Cue Processing ◽  
The Impact

During navigation, landmark processing is critical either for generating an allocentric-based cognitive map or in facilitating egocentric-based strategies. Increasing evidence from manipulation and single-unit recording studies has highlighted the role of the entorhinal cortex in processing landmarks. In particular, the lateral (LEC) and medial (MEC) sub-regions of the entorhinal cortex have been shown to attend to proximal and distal landmarks, respectively. Recent studies have identified a further dissociation in cue processing between the LEC and MEC based on spatial frames of reference. Neurons in the LEC preferentially encode egocentric cues while those in the MEC encode allocentric cues. In this study, we assessed the impact of disrupting the LEC on landmark-based spatial memory in both egocentric and allocentric reference frames. Animals that received excitotoxic lesions of the LEC were significantly impaired, relative to controls, on both egocentric and allocentric versions of an object–place association task. Notably, LEC lesioned animals performed at chance on the egocentric version but above chance on the allocentric version. There was no significant difference in performance between the two groups on an object recognition and spatial T-maze task. Taken together, these results indicate that the LEC plays a role in feature integration more broadly and in specifically processing spatial information within an egocentric reference frame.

Connectivity-Related Roles of Contralesional Brain Regions for Motor Performance Early after Stroke

2020 ◽  
Author(s):  
Lukas Hensel ◽  
Caroline Tscherpel ◽  
Jana Freytag ◽  
Stella Ritter ◽  
Anne K Rehme ◽  
...  
Keyword(s):  
Neural Activity ◽  
Motor Performance ◽  
Primary Motor Cortex ◽  
Effective Connectivity ◽  
Premotor Cortex ◽  
Brain Regions ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Anterior Intraparietal Sulcus

Abstract Hemiparesis after stroke is associated with increased neural activity not only in the lesioned but also in the contralesional hemisphere. While most studies have focused on the role of contralesional primary motor cortex (M1) activity for motor performance, data on other areas within the unaffected hemisphere are scarce, especially early after stroke. We here combined functional magnetic resonance imaging (fMRI) and transcranial magnetic stimulation (TMS) to elucidate the contribution of contralesional M1, dorsal premotor cortex (dPMC), and anterior intraparietal sulcus (aIPS) for the stroke-affected hand within the first 10 days after stroke. We used “online” TMS to interfere with neural activity at subject-specific fMRI coordinates while recording 3D movement kinematics. Interfering with aIPS activity improved tapping performance in patients, but not healthy controls, suggesting a maladaptive role of this region early poststroke. Analyzing effective connectivity parameters using a Lasso prediction model revealed that behavioral TMS effects were predicted by the coupling of the stimulated aIPS with dPMC and ipsilesional M1. In conclusion, we found a strong link between patterns of frontoparietal connectivity and TMS effects, indicating a detrimental influence of the contralesional aIPS on motor performance early after stroke.

scholarly journals Fear-induced increases in loss aversion are linked to increased neural negative-value coding

2020 ◽  
Vol 15 (6) ◽  
pp. 661-670
Author(s):  
Stefan Schulreich ◽  
Holger Gerhardt ◽  
Dar Meshi ◽  
Hauke R Heekeren
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Loss Aversion ◽  
Neural Mechanism ◽  
Brain Regions ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Fearful Faces ◽  
Value Coding

Abstract Human decisions are often influenced by emotions. An economically relevant example is the role of fear in generating loss aversion. Previous research implicates the amygdala as a key brain structure in the experience of fear and loss aversion. The neural mechanism behind emotional influences on loss aversion is, however, unclear. To address this, we measured brain activation with functional magnetic resonance imaging (fMRI) while participants made decisions about monetary gambles after viewing fearful or neutral faces. We observed that loss aversion following the presentation of neutral faces was mainly predicted by greater deactivations for prospective losses (relative to activations for prospective gains) in several brain regions, including the amygdala. By contrast, increases in loss aversion following the presentation of fearful faces were mainly predicted by greater activations for prospective losses. These findings suggest a fear-induced shift from positive to negative value coding that reflects a context-dependent involvement of distinct valuation processes.

scholarly journals A Distinct Role of the Temporal-Parietal Junction in Predicting Socially Guided Decisions

Science ◽  
2012 ◽  
Vol 337 (6090) ◽  
pp. 109-111 ◽  
Author(s):  
R. McKell Carter ◽  
Daniel L. Bowling ◽  
Crystal Reeck ◽  
Scott A. Huettel
Keyword(s):  
Pattern Analysis ◽  
Multivariate Pattern Analysis ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Incentive Compatible ◽  
Future Behavior ◽  
Human Participants ◽  
Multivariate Pattern ◽  
Distinct Role

To make adaptive decisions in a social context, humans must identify relevant agents in the environment, infer their underlying strategies and motivations, and predict their upcoming actions. We used functional magnetic resonance imaging, in conjunction with combinatorial multivariate pattern analysis, to predict human participants’ subsequent decisions in an incentive-compatible poker game. We found that signals from the temporal-parietal junction provided unique information about the nature of the upcoming decision, and that information was specific to decisions against agents who were both social and relevant for future behavior.

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