Hand–Arm-Vibration Syndrome (HAVS): Is There a Central Nervous Component? an fMRI Study

2002 ◽  
Vol 27 (6) ◽  
pp. 514-519 ◽  
Author(s):  
G. LUNDBORG ◽  
B. ROSÉN ◽  
L. KNUTSSON ◽  
S. HOLTÅS ◽  
F. STÅHLBERG ◽  
...  
Keyword(s):  
Tactile Stimulation ◽  
Motor Dysfunction ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Vibration Syndrome ◽  
Ipsilateral Hemisphere ◽  
Neuromuscular Dysfunction ◽  
Fmri Study ◽  
The Brain

Hand-held vibrating tools may result in neuromuscular dysfunction and vasospastic problems of the hand. Sensory and motor dysfunction can be explained by injury to peripheral structures, but could also be due to changes in cortical somatotopic mapping of the hand in the brain. The purpose of the present study was to use functional magnetic resonance imaging (fMRI) to assess the somatotopic cortical representation of the hands of workers subjected to occupational vibration. The study included six men with severe vibration exposures who were suffering from hand–arm-vibration syndrome (HAVS) and six controls. The analysis focused on the pattern and degree of activation of contra- and ipsilateral hemispheres of the brain with tactile stimulation and motor activation of the hand. These stimulations resulted in well-defined activation of the contralateral, and to a lesser extent the ipsilateral hemisphere. Statistical analysis of this limited patient material did not indicate any significant somatotopic cortical changes following long-term exposure to vibrating hand-held tools, although there was a tendency to a shift of activation towards the more cranial parts of the cortex in the patient group.

scholarly journals Increased neural reactivity to emotional pictures in men with high hair testosterone concentrations

2019 ◽  
Vol 14 (9) ◽  
pp. 1009-1016
Author(s):  
Sanja Klein ◽  
Onno Kruse ◽  
Isabell Tapia León ◽  
Tobias Stalder ◽  
Rudolf Stark ◽  
...  
Keyword(s):  
Emotional Reactivity ◽  
Neural Activation ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Testosterone Levels ◽  
Passive Viewing ◽  
Emotional Pictures ◽  
Neural Reactivity ◽  
The Brain

Abstract Testosterone has been linked to alterations in the activity of emotion neurocircuitry including amygdala, orbitofrontal cortex (OFC) and insula and diminished functional amygdala/prefrontal coupling. Such associations have only ever been studied using acute measures of testosterone, thus little is known about respective relationships with long-term testosterone secretion. Here, we examine associations between hair testosterone concentration (HTC), an index of long-term cumulative testosterone levels and neural reactivity during an emotional passive viewing task using functional magnetic resonance imaging (fMRI). Forty-six men viewed negative, positive and neutral pictures in the MRI. HTCs were assessed from 2 cm hair segments. The emotional paradigm elicited neural activation in the amygdala, insula and OFC. HTCs were associated with increased reactivity to negative pictures in the insula and increased reactivity to positive pictures in the OFC. We show an association of long-term testosterone levels with increased emotional reactivity in the brain. These results suggest a heightened emotional vigilance in individuals with high trait testosterone levels.

Negation and the Brain

2020 ◽  
pp. 693-712
Author(s):  
Yosef Grodzinsky ◽  
Virginia Jaichenco ◽  
Isabelle Deschamps ◽  
María Elina Sánchez ◽  
Martín Fuchs ◽  
...  
Keyword(s):  
Methodological Problem ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Behavioral Experiments ◽  
Behavioral Studies ◽  
Processing Cost ◽  
Fmri Study ◽  
Downward Entailing ◽  
Measuring Reaction Time ◽  
The Brain

This chapter reports an investigation into possible brain bases for negation. It begins with a review of negation experiments that used behavioral studies (measuring Reaction Time—RT), and functional Magnetic Resonance Imaging (fMRI) experiments that sought to identify local activations that correlate with the presence of negation. The chapter dwells on a major methodological problem that permeates the experimental study of negation processing, and proposes a solution: instead of overt negation, we study expressions that contain a covert negation—expressions that are Downward Entailing (DE) as evinced by their ability to reverse inferences and license NPIs in their scope. DE operators are thus taken to contain a hidden, or covert, negation, and contrast with the Upward Entailing counterparts (few vs. many; less vs. more). The chapter reviews behavioral experiments in healthy adults that indicate that DE has a processing cost, and an fMRI study that finds a single brain location for this computation. These results serve as a basis for an experiment on individuals with Broca’s aphasia. Tests with DE and UE quantifiers with these patients resulted in a mixed picture, which is discussed and its implications are derived.

scholarly journals Mapping of Brain Functions and Spatial Luminance Distributions as Innovative Tools for Assessing Discomfort Glare in the Built Environment

2007 ◽  
Vol 4 (1) ◽  
Author(s):  
Peter Raynham ◽  
Werner Osterhaus ◽  
Michael Davies
Keyword(s):  
Built Environment ◽  
Proof Of Concept ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Brain Functions ◽  
Discomfort Glare ◽  
Innovative Tool ◽  
New Research ◽  
The Brain

A series of "proof-of-concept" projects are set out aimed at bringing together built environment researchers attempting to understand what constitutes ‘comfortable’ space and neuroscientists investigating the functional characteristics of the human brain. The long-term goal is to address the question of whether there are regions of the brain that are specifically engaged when people experience spaces they consider to be comfortable, pleasing or even beautiful. Glare is an area of research that has been recognised as a problem in both interior and exterior lighting. Recent advances in technology make it an ideal candidate for the proposed “proof-of-concept” study. The mapping of brain functions through functional magnetic resonance imaging, the mapping of luminance distributionsin a visual scene, and the study of distraction and its influence on discomfort glare can be combined to form the basis of an innovative tool box for new research.

scholarly journals Effect of Gayatri Mantra Meditation on Meditation Naive Subjects: an EEG and fMRI Pilot Study

2016 ◽  
Vol 3 (2) ◽  
Author(s):  
Susan Thomas ◽  
Shobini L. Rao
Keyword(s):  
Inferior Parietal Lobule ◽  
Focus Attention ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Fmri Study ◽  
Maximum Activation ◽  
Before And After ◽  
Eeg Changes ◽  
Mantra Meditation ◽  
The Brain

A mantra is a word or phrase repeated aloud or silently and used to focus attention. Meditation using mantras is widely practiced in India. However, research on the effects of mantra meditation on the brain is sparse. The aim was to study the effect of listening to Gayatri mantra on the brain using Elecroencephalograph (EEG) functional Magnetic Resonance Imaging (fMRI). Sample included 8 meditation naive subjects, who have not been practicing any form of meditation. There were 12 subjects for the EEG study and 8 subjects for the fMRI study. The results showed that the areas that had maximum activation were the bilateral superior temporal gyri, right temporal lobe, right insula, left inferior parietal lobule, lateral globuspallidus and culmen of the cerebellum. There were some EEG changes before and after listening to Gayatri mantra also, but reliable analysis could not be carried out due to the less number of samples. Results indicate that mantra meditation can result in changes in the brain.

scholarly journals Perceiving actions before they happen: psychological dimensions scaffold neural action prediction

2020 ◽  
Author(s):  
Mark A Thornton ◽  
Diana I Tamir
Keyword(s):  
Magnetic Resonance Imaging ◽  
Functional Neuroimaging ◽  
Social World ◽  
Action Space ◽  
Action Prediction ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
The Social ◽  
Psychological Dimensions ◽  
The Brain

Abstract The social world buzzes with action. People constantly walk, talk, eat, work, play, snooze and so on. To interact with others successfully, we need to both understand their current actions and predict their future actions. Here we used functional neuroimaging to test the hypothesis that people do both at the same time: when the brain perceives an action, it simultaneously encodes likely future actions. Specifically, we hypothesized that the brain represents perceived actions using a map that encodes which actions will occur next: the six-dimensional Abstraction, Creation, Tradition, Food(-relevance), Animacy and Spiritualism Taxonomy (ACT-FAST) action space. Within this space, the closer two actions are, the more likely they are to precede or follow each other. To test this hypothesis, participants watched a video featuring naturalistic sequences of actions while undergoing functional magnetic resonance imaging (fMRI) scanning. We first use a decoding model to demonstrate that the brain uses ACT-FAST to represent current actions. We then successfully predicted as-yet unseen actions, up to three actions into the future, based on their proximity to the current action’s coordinates in ACT-FAST space. This finding suggests that the brain represents actions using a six-dimensional action space that gives people an automatic glimpse of future actions.

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.

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