Is Transient Global Amnesia a Network Disease?

2018 ◽  
Vol 80 (5-6) ◽  
pp. 345-354 ◽  
Author(s):  
Kang Min Park ◽  
Byung In Lee ◽  
Sung Eun Kim
Keyword(s):  
White Matter ◽  
Healthy Subjects ◽  
Transient Global Amnesia ◽  
Brain Network ◽  
Network Measures ◽  
Postcentral Gyrus ◽  
Frontal Operculum ◽  
Global Amnesia ◽  
The Right ◽  
The Brain

Background: We evaluated a brain network using graph theoretical analysis and microstructural abnormalities of the white matter in patients with transient global amnesia (TGA). Methods: Twenty patients with TGA and healthy control subjects were recruited, and they underwent diffusion tensor imaging (DTI) scans. Graph theory was applied to obtain network measures based on DTI data. We investigated the network measures and microstructural abnormalities of white matter using tract-based spatial statistics (TBSS) analysis in the patients with TGA. Results: Measures of global topology were not different between the patients with TGA and healthy subjects. However, there were significant differences of hubs organization; the strength of the right superior and inferior orbitofrontal, the right inferior frontal operculum, the left superior parietal, and left postcentral gyrus, the cluster coefficient of the right middle orbitofrontal and left inferior parietal gyrus, the betweenness centrality of the left angular gyrus, and the pagerank centrality of the right superior and inferior orbitofrontal, right inferior frontal operculum, left superior parietal, and left postcentral gyrus in the patients with TGA were significantly lower than those in healthy subjects. Regarding the analysis of the white matter microstructure with TBSS, there were no differences in the fractional anisotropy and mean diffusivity values between the 2 groups. Conclusions: We newly identify a reorganization of network hubs of the brain network in patients with TGA, especially in the regions of the default-mode network. These alterations of the brain network may play a role in the pathophysiologic mechanism underlying TGA and suggest that TGA is a network disease.

Impulsivity and neural correlates of response inhibition in schizophrenia

2010 ◽  
Vol 41 (2) ◽  
pp. 291-299 ◽  
Author(s):  
A. Kaladjian ◽  
R. Jeanningros ◽  
J.-M. Azorin ◽  
J.-L. Anton ◽  
P. Mazzola-Pomietto
Keyword(s):  
Response Inhibition ◽  
Healthy Subjects ◽  
Neural Correlates ◽  
Brain Network ◽  
Cerebral Activation ◽  
Neural Processes ◽  
Psychometric Measures ◽  
The Right ◽  
The Relationship ◽  
The Brain

BackgroundThe clinical picture of schizophrenia is frequently worsened by manifestations of impulsivity. However, the neural correlates of impulsivity in this disorder are poorly known. Although impulsivity has been related to disturbances of the neural processes underlying response inhibition, no studies have yet examined the relationship between these processes and psychometric measures of impulsivity in schizophrenia. This was the aim of the current investigation.MethodEvent-related functional magnetic resonance imaging in conjunction with a Go/NoGo task was employed to probe the neural activity associated with response inhibition in 26 patients with schizophrenia and 30 healthy comparison subjects. All participants also completed the Barratt Impulsiveness Scale – version 11 (BIS-11). Voxel-wise regression analyses were used to examine the relationship between the BIS-11 score and brain activation during response inhibition in each group.ResultsPatients with schizophrenia were more impulsive than healthy subjects, as indicated by higher BIS-11 scores. Patients, but not healthy subjects, were found to display a positive correlation between these scores and cerebral activation associated with response inhibition. This correlation involves a unique cluster localized within the right ventrolateral prefrontal cortex (VLPFC), a key node of the brain network subserving response inhibition.ConclusionsWe evidenced in patients with schizophrenia that greater BIS-11 scores are associated with greater activation within the right VLPFC during response inhibition. This finding suggests that the efficiency of this brain region to process inhibitory control is reduced in the more impulsive patients.

Transient global amnesia following transoesophageal echocardiography

2020 ◽  
Vol 13 (4) ◽  
pp. e234751
Author(s):  
Mark Philip Cassar ◽  
Katrin Balkhausen
Keyword(s):  
Septal Defect ◽  
Transient Global Amnesia ◽  
Anterograde Amnesia ◽  
Transoesophageal Echocardiography ◽  
Sudden Onset ◽  
Clinical Suspicion ◽  
Secundum Atrial Septal Defect ◽  
Global Amnesia ◽  
The Right ◽  
The Brain

Transient global amnesia (TGA) is characterised by the sudden onset of isolated anterograde amnesia, which resolves within 24 hours. Here, we discuss the case of a 63-year-old woman who underwent a transoesophageal echocardiogram (TOE) as part of her workup for pulmonary hypertension. She was well on the morning of the procedure, and following consent, underwent transoesophageal echocardiography without sedation. The procedure was uncomplicated with normal observations throughout, confirming a suspected secundum atrial septal defect. Immediately following oesophageal extubation, it was noted that the patient was disoriented. The physical neurological examination was unremarkable. Urgent MRI of the brain showed normal anatomy; a diagnosis of TGA was made. Within 10 hours of onset, the patient was back to her baseline. Isolated anterograde amnesia following transoesophageal echocardiography should raise the clinical suspicion of TGA. Prompt clinical examination and support from other specialties are paramount in making the right diagnosis.

scholarly journals Recovery from Transient Global Amnesia Following Restoration of Hippocampal and Fronto–Cingulate Perfusion

2010 ◽  
Vol 22 (3-4) ◽  
pp. 131-139 ◽  
Author(s):  
Paolo Caffarra ◽  
Letizia Concari ◽  
Simona Gardini ◽  
Sabrina Spaggiari ◽  
Francesca Dieci ◽  
...  
Keyword(s):  
Acute Phase ◽  
Neuropsychological Testing ◽  
Transient Global Amnesia ◽  
Normal Limits ◽  
Global Amnesia ◽  
One Year ◽  
The Right ◽  
Rcbf Spect ◽  
Subject Comparison

A patient who suffered a transient global amnesia (TGA) attack underwent regional cerebral blood flow (rCBF) SPECT imaging and neuropsychological testing in the acute phase, after one month and after one year. Neuropsychological testing in the acute phase showed a pattern of anterograde and retrograde amnesia, whereas memory was within age normal limits at follow up. SPECT data were analysed with a within subject comparison and also compared with those of a group of healthy controls. Within subject comparison between the one month follow up and the acute phase detected increases in rCBF in the hippocampus bilaterally; further rCBF increases in the right hippocampus were detected after one year. Compared to controls, significant hypoperfusion was found in the right precentral, cingulate and medial frontal gyri in the acute phase; after one month significant hypoperfusion was detected in the right precentral and cingulate gyri and the left postcentral gyrus; after one year no significant hypoperfusion appeared. The restoration of memory was paralleled by rCBF increases in the hippocampus and fronto-limbic-parietal cortex; after one year neither significant rCBF differences nor cognitive deficits were detectable. In conclusion, these data indicate that TGA had no long lasting cognitive and neural alterations in this patient.

scholarly journals BrainNetVis: An Open-Access Tool to Effectively Quantify and Visualize Brain Networks

2011 ◽  
Vol 2011 ◽  
pp. 1-12 ◽  
Author(s):  
Eleni G. Christodoulou ◽  
Vangelis Sakkalis ◽  
Vassilis Tsiaras ◽  
Ioannis G. Tollis
Keyword(s):  
Open Access ◽  
Brain Network ◽  
Global Network ◽  
Control Group ◽  
Network Modelling ◽  
Network Information ◽  
Network Measures ◽  
Graph Metrics ◽  
Network Metrics ◽  
The Brain

This paper presents BrainNetVis, a tool which serves brain network modelling and visualization, by providing both quantitative and qualitative network measures of brain interconnectivity. It emphasizes the needs that led to the creation of this tool by presenting similar works in the field and by describing how our tool contributes to the existing scenery. It also describes the methods used for the calculation of the graph metrics (global network metrics and vertex metrics), which carry the brain network information. To make the methods clear and understandable, we use an exemplar dataset throughout the paper, on which the calculations and the visualizations are performed. This dataset consists of an alcoholic and a control group of subjects.

scholarly journals Mindfulness Meditation Is Related to Long-Lasting Changes in Hippocampal Functional Topology during Resting State: A Magnetoencephalography Study

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Anna Lardone ◽  
Marianna Liparoti ◽  
Pierpaolo Sorrentino ◽  
Rosaria Rucco ◽  
Francesca Jacini ◽  
...  
Keyword(s):  
Resting State ◽  
Mindfulness Meditation ◽  
Brain Connectivity ◽  
Brain Networks ◽  
Brain Network ◽  
Long Term Effects ◽  
Age Related ◽  
Functional Topology ◽  
The Right ◽  
The Brain

It has been suggested that the practice of meditation is associated to neuroplasticity phenomena, reducing age-related brain degeneration and improving cognitive functions. Neuroimaging studies have shown that the brain connectivity changes in meditators. In the present work, we aim to describe the possible long-term effects of meditation on the brain networks. To this aim, we used magnetoencephalography to study functional resting-state brain networks in Vipassana meditators. We observed topological modifications in the brain network in meditators compared to controls. More specifically, in the theta band, the meditators showed statistically significant (p corrected = 0.009) higher degree (a centrality index that represents the number of connections incident upon a given node) in the right hippocampus as compared to controls. Taking into account the role of the hippocampus in memory processes, and in the pathophysiology of Alzheimer’s disease, meditation might have a potential role in a panel of preventive strategies.

scholarly journals A PET study in healthy subjects of brain exposure of 11C-labelled osimertinib – A drug intended for treatment of brain metastases in non-small cell lung cancer

2019 ◽  
Vol 40 (4) ◽  
pp. 799-807 ◽  
Author(s):  
Andrea Varrone ◽  
Katarina Varnäs ◽  
Aurelija Jucaite ◽  
Zsolt Cselényi ◽  
Peter Johnström ◽  
...  
Keyword(s):  
White Matter ◽  
Brain Metastases ◽  
Blood Brain Barrier ◽  
Healthy Subjects ◽  
Standardized Uptake Value ◽  
Brain Barrier ◽  
Pharmacokinetic Parameters ◽  
Blood Brain ◽  
Brain Exposure ◽  
The Brain

Osimertinib is a tyrosine kinase inhibitor (TKI) of the mutated epidermal growth factor receptor (EGFRm) with observed efficacy in patients with brain metastases. Brain exposure and drug distribution in tumor regions are important criteria for evaluation and confirmation of CNS efficacy. The aim of this PET study was therefore to determine brain distribution and exposure of 11C-labelled osimertinib administered intravenously in subjects with an intact blood–brain barrier. Eight male healthy subjects (age 52 ± 8 years) underwent one PET measurement with 11C-osimertinib. The pharmacokinetic parameters Cmax (brain) (standardized uptake value), Tmax (brain) and AUC0–90 min brain/blood ratio were calculated. The outcome measure for 11C-osimertinib brain exposure was the total distribution volume ( VT). 11C-osimertinib distributed rapidly to the brain, with higher uptake in grey than in white matter. Mean Cmax, Tmax and AUC0–90 min brain/blood ratio were 1.5 (range 1–1.8), 13 min (range 5–30 min), and 3.8 (range 3.3–4.1). Whole brain and white matter VT were 14 mL×cm−3 (range 11–18) and 7 mL×cm−3 (range 5–12). This study in healthy volunteers shows that 11C-osimertinib penetrates the intact blood–brain barrier. The approach used further illustrates the role of molecular imaging in facilitating the development of novel drugs for the treatment of malignancies affecting the brain.

Altered brain network centrality in patients with trigeminal neuralgia: a resting-state fMRI study

2019 ◽  
Vol 61 (1) ◽  
pp. 67-75 ◽  
Author(s):  
Pei-Wen Zhu ◽  
You Chen ◽  
Ying-Xin Gong ◽  
Nan Jiang ◽  
Wen-Feng Liu ◽  
...  
Keyword(s):  
Trigeminal Neuralgia ◽  
Brain Activity ◽  
Characteristic Curve ◽  
Brain Regions ◽  
Brain Network ◽  
Network Activity ◽  
Degree Centrality ◽  
Healthy Controls ◽  
Postcentral Gyrus ◽  
The Right

Background Neuroimaging studies revealed that trigeminal neuralgia was related to alternations in brain anatomical function and regional function. However, the functional characteristics of network organization in the whole brain is unknown. Purpose The aim of the present study was to analyze potential functional network brain-activity changes and their relationships with clinical features in patients with trigeminal neuralgia via the voxel-wise degree centrality method. Material and Methods This study involved a total of 28 trigeminal neuralgia patients (12 men, 16 women) and 28 healthy controls matched in sex, age, and education. Spontaneous brain activity was evaluated by degree centrality. Correlation analysis was used to examine the correlations between behavioral performance and average degree centrality values in several brain regions. Results Compared with healthy controls, trigeminal neuralgia patients had significantly higher degree centrality values in the right lingual gyrus, right postcentral gyrus, left paracentral lobule, and bilateral inferior cerebellum. Receiver operative characteristic curve analysis of each brain region confirmed excellent accuracy of the areas under the curve. There was a positive correlation between the mean degree centrality value of the right postcentral gyrus and VAS score (r = 0.885, P < 0.001). Conclusions Trigeminal neuralgia causes abnormal brain network activity in multiple brain regions, which may be related to underlying disease mechanisms.

scholarly journals Association Between Trait Empathy and Resting Brain Activity in Women With Primary Dysmenorrhea During the Pain and Pain-Free Phases

2020 ◽  
Vol 11 ◽  
Author(s):  
Wanghuan Dun ◽  
Tongtong Fan ◽  
Qiming Wang ◽  
Ke Wang ◽  
Jing Yang ◽  
...  
Keyword(s):  
Brain Activity ◽  
Inferior Frontal Gyrus ◽  
Brain Network ◽  
Primary Dysmenorrhea ◽  
Pain Experience ◽  
Current State ◽  
The Neural Network ◽  
The Right ◽  
The Brain

Empathy refers to the ability to understand someone else's emotions and fluctuates with the current state in healthy individuals. However, little is known about the neural network of empathy in clinical populations at different pain states. The current study aimed to examine the effects of long-term pain on empathy-related networks and whether empathy varied at different pain states by studying primary dysmenorrhea (PDM) patients. Multivariate partial least squares was employed in 46 PDM women and 46 healthy controls (HC) during periovulatory, luteal, and menstruation phases. We identified neural networks associated with different aspects of empathy in both groups. Part of the obtained empathy-related network in PDM exhibited a similar activity compared with HC, including the right anterior insula and other regions, whereas others have an opposite activity in PDM, including the inferior frontal gyrus and right inferior parietal lobule. These results indicated an abnormal regulation to empathy in PDM. Furthermore, there was no difference in empathy association patterns in PDM between the pain and pain-free states. This study suggested that long-term pain experience may lead to an abnormal function of the brain network for empathy processing that did not vary with the pain or pain-free state across the menstrual cycle.

scholarly journals Familial Retinal Arteriolar Tortuosity with Acute Hippocampal Infarction

2017 ◽  
Vol 8 (1) ◽  
pp. 185-189 ◽  
Author(s):  
Tae Hee Kim ◽  
Sonia Lee ◽  
Su Jin Lim
Keyword(s):  
Past History ◽  
Brain Magnetic Resonance Imaging ◽  
Transient Global Amnesia ◽  
Subcortical White Matter ◽  
Blurred Vision ◽  
Retinal Arterioles ◽  
History Of ◽  
Global Amnesia ◽  
The Brain ◽  
Retinal Arteriolar

Purpose: To report a case of familial retinal arteriolar tortuosity with acute hippocampal infarction. Method: Single-patient case report. Results: A 50-year-old woman presented with blurred vision and was found to have cataract, retinal hemorrhages, and tortuous retinal arterioles in both eyes. Similar findings of tortuous retinal arterioles were observed in her daughter and son. In her past history of 6 years prior to the visit, she had been diagnosed with transient global amnesia after brain magnetic resonance imaging, which showed hippocampal infarction and multiple chronic ischemic lesions in the periventricular and subcortical white matter. Conclusion: Familial retinal arteriolar tortuosity is known to affect the retinal vessels only. To our knowledge, this is the first report of ischemic injury to the brain in a patient with familial retinal arteriolar tortuosity.

scholarly journals Transient Global Amnesia and Brain Tumour: Chance Concurrence or Aetiological Association Case Report and Systematic Literature Review

2015 ◽  
Vol 7 (1) ◽  
pp. 18-25 ◽  
Author(s):  
Phil Milburn-McNulty ◽  
Andrew J. Larner
Keyword(s):  
Systematic Review ◽  
Case Report ◽  
Literature Review ◽  
Brain Tumour ◽  
Transient Global Amnesia ◽  
Low Grade ◽  
Review Of The Literature ◽  
Global Amnesia ◽  
The Right ◽  
Clinical Diagnostic Criteria

We report a patient presenting with episodes of transient amnesia, some with features suggestive of transient global amnesia (TGA), and some more reminiscent of transient epileptic amnesia. Investigation with neuroimaging revealed an intrinsic lesion in the right amygdala, with features suggestive of low-grade neoplasia. We undertook a systematic review of the literature on TGA and brain tumour. Fewer than 20 cases were identified, some of which did not conform to the clinical diagnostic criteria for TGA. Hence, the concurrence of brain tumour and TGA is very rare and of doubtful aetiological relevance. In some brain tumour-associated cases, epilepsy may be masquerading as TGA.

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