scholarly journals Parietal Lobe Reorganization and Widespread Functional Connectivity Integration in Upper-Limb Amputees: A rs-fMRI Study

2021 ◽  
Vol 15 ◽  
Author(s):  
Bingbo Bao ◽  
Haifeng Wei ◽  
Pengbo Luo ◽  
Hongyi Zhu ◽  
Wencheng Hu ◽  
...  
Keyword(s):  
Body Image ◽  
Functional Connectivity ◽  
Upper Limb ◽  
Parietal Lobe ◽  
Low Frequency ◽  
Limb Amputation ◽  
Whole Brain ◽  
Upper Limb Amputation ◽  
Frequency Fluctuations ◽  
The Right

The right parietal lobe plays an important role in body image, and disorders of body image emerge after lesions in the parietal lobe or with parietal lobe epilepsy. Body image disorder also often accompanies upper-limb amputation, in which the patient misperceives that their missing limb is still part of their body. Cortical reorganization is known to occur after upper-limb amputation, but it is not clear how widespread and to what degree functional connectivity (FC) is reorganized post-amputation, nor whether such changes might be related to misperceptions of body image. Twenty-four subjects who had a traumatically upper-limb amputees (ULAs) and 24 age-matched healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (rs-fMRI) scans. Regions of interest (ROIs) in the right superior parietal gyrus (SPG_R) and right inferior parietal lobule (IPL_R) were defined using BrainNet Viewer. We calculated the amplitude of low-frequency fluctuations (ALFF) in ROIs and correlated the ROI mean amplitude of low-frequency fluctuations (mALFF) and mean scores on the phantom limb sensation (PLS) scale and beck depression index (BDI). We also calculated ROIs and whole-brain FC. Compared to the HC group, we observed significantly increased activation (mALFF) in ROIs of the ULA group. Moreover, correlation analyses revealed a significant positive correlation between ROI mALFF and scores on the PLS. There was a significant negative correlation between the SPG_R mALFF and BDI scores. Seed-based, whole-brain FC analysis revealed that FC in the ULA group significantly decreased in many brain regions across the entire brain. The right parietal lobe appears to be involved in some aspect of body awareness and depression in amputation patients. Upper-limb amputation results not only in reorganization in the local brain area formerly representing the missing limb, but also results in more widespread reorganization through FC changes in whole brain.

scholarly journals Capturing Neuroplastic Changes after iTBS in Patients with Post-Stroke Aphasia: A Pilot fMRI Study

2021 ◽  
Vol 11 (11) ◽  
pp. 1451
Author(s):  
Shuo Xu ◽  
Qing Yang ◽  
Mengye Chen ◽  
Panmo Deng ◽  
Ren Zhuang ◽  
...  
Keyword(s):  
Functional Connectivity ◽  
Primary Motor Cortex ◽  
High Efficiency ◽  
Parietal Lobe ◽  
Low Frequency ◽  
Brain Regions ◽  
Post Stroke ◽  
Before And After ◽  
Mri Scans ◽  
The Right

Intermittent theta-burst stimulation (iTBS) is a high-efficiency transcranial magnetic stimulation (TMS) paradigm that has been applied to post-stroke aphasia (PSA). However, its efficacy mechanisms have not been clarified. This study aimed to explore the immediate effects of iTBS of the primary motor cortex (M1) of the affected hemisphere, on the functional activities and connectivity of the brains of PSA patients. A total of 16 patients with aphasia after stroke received iTBS with 800 pulses for 300 s. All patients underwent motor, language, and cognitive assessments and resting-state functional MRI scans immediately before and after the iTBS intervention. Regional, seed-based connectivity, and graph-based measures were used to test the immediate functional effects of the iTBS intervention, including the fractional amplitude of low-frequency fluctuation (fALFF), degree centrality (DC), and functional connectivity (FC) of the left M1 area throughout the whole brain. The results showed that after one session of iTBS intervention, the fALFF, DC, and FC values changed significantly in the patients’ brains. Specifically, the DC values were significantly higher in the right middle frontal gyrus and parts of the left parietal lobe (p < 0.05), while fALFF values were significantly lower in the right medial frontal lobe and parts of the left intracalcarine cortex (p < 0.05), and the strength of the functional connectivity between the left M1 area and the left superior frontal gyrus was reduced (p < 0.05). Our findings provided preliminary evidences that the iTBS on the ipsilesional M1 could induce neural activity and functional connectivity changes in the motor, language, and other brain regions in patients with PSA, which may promote neuroplasticity and functional recovery.

scholarly journals Amplitude of Low-Frequency Fluctuations and Resting-State Functional Connectivity in Trait Positive Empathy: A Resting-State fMRI Study

2021 ◽  
Vol 12 ◽  
Author(s):  
Tong Yue ◽  
Jia Zhao ◽  
Anguo Fu
Keyword(s):  
Functional Connectivity ◽  
Resting State ◽  
Positive Emotions ◽  
Negative Emotion ◽  
Low Frequency ◽  
Middle Temporal Gyrus ◽  
Resting State Functional Connectivity ◽  
Frequency Fluctuations ◽  
The Right ◽  
Left Middle

Positive empathy is the ability to share and understand the positive emotions of others. In recent years, although positive empathy has received more and more attention, trait positive empathy (TPE)-related spontaneous brain activity during the resting state has not been extensively explored. We used the amplitude of low-frequency fluctuations (ALFFs) and resting-state functional connectivity (RSFC) of the resting-state functional magnetic resonance imaging signal to explore TPE-associated brain regions. We found that higher TPE was associated with higher ALFFs in the right insula and lower ALFFs in the right subgenual cingulate (SGC), right dorsomedial prefrontal cortex (dmPFC), and right precuneus. RSFC analyses showed that higher functional connectivity between the right insula and left parahippocampal gyrus, left inferior parietal lobule and left middle temporal gyrus were related to higher TPE. Moreover, the connection between the right dmPFC and the left medial orbitofrontal cortex, left middle occipital gyrus and left posterior cingulate cortex were positively related to TPE. Meanwhile, the strength of functional connectivity between the right SGC and left supplementary motor area was positively associated with TPE. These findings may indicate that TPE is linked to emotional (especially the experience of more positive emotions and better negative emotion regulation) and self-referential processing.

A small contact burn injury requiring upper limb amputation

Burns ◽  
2000 ◽  
Vol 26 (7) ◽  
pp. 656-658 ◽  
Author(s):  
R.J.I Colville ◽  
R.B Berry
Keyword(s):  
Upper Limb ◽  
Burn Injury ◽  
Limb Amputation ◽  
Upper Limb Amputation

scholarly journals Elective amputation of the upper limb is an option in the treatment of traumatic injuries of the brachial plexus?

2017 ◽  
Vol 75 (9) ◽  
pp. 667-670 ◽  
Author(s):  
Mário Gilberto Siqueira ◽  
Roberto Sérgio Martins ◽  
Carlos Otto Heise ◽  
Luciano Foroni
Keyword(s):  
Peripheral Nerve ◽  
Brachial Plexus ◽  
Upper Limb ◽  
Limb Amputation ◽  
Brachial Plexus Palsy ◽  
Traumatic Injuries ◽  
Upper Limb Amputation ◽  
Pros And Cons ◽  
Post Traumatic ◽  
Active Patients

ABSTRACT The treatment of complete post-traumatic brachial plexus palsy resulting in a flail shoulder and upper extremity remains a challenge to peripheral nerve surgeons. The option of upper limb amputation is controversial and scarcely discussed in the literature. We believe that elective amputation still has a role in the treatment of select cases. The pros and cons of the procedure should be intensely discussed with the patient by a multidisciplinary team. Better outcomes are usually achieved in active patients who strongly advocate for the procedure.

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