Repetitive transcranial magnetic stimulation over left angular gyrus modulates the predictability gain in degraded speech comprehension

Abstract Background: Stimulating superficial brain regions highly associated with the hippocampus by repetitive transcranial magnetic stimulation (rTMS) may improve memory of Alzheimer disease (AD) spectrum patients. Methods: We recruited 26 mild cognitive impairment (MCI) and AD patients. All the patients were stimulated to the left angular gyrus, which was confirmed a strong link to the hippocampus through neuroimaging studies, by the neuro-navigated rTMS for four weeks. Automated fiber quantification (AFQ) using diffusion tensor imaging (DTI) metrics and graph theory analysis on functional network were employed to detect the neuroplasticity of brain networks. Results: After neuro-navigated rTMS intervention, the episodic memory and language function of patients were significantly improved. Increased white matter integrity of right anterior thalamic radiation among MCI patients, while decreased functional network properties of thalamus subregions were observed. It is worth noting that the improvement of cognition was associated with the neuroplasticity of thalamic systemConclusions: We speculated that the rTMS intervention targeting left angular gyrus may be served as a strategy to improve cognitive impairment in AD spectrum patients, supporting by the neuroplasticity of thalamic system, especially in the early disease process at the stage of MCI.

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A pilot trial of repetitive transcranial magnetic stimulation of the dorsomedial prefrontal cortex in anorexia nervosa: resting fMRI correlates of response

Journal of Eating Disorders ◽

10.1186/s40337-021-00411-x ◽

2021 ◽

Vol 9 (1) ◽

Author(s):

D. Blake Woodside ◽

Katharine Dunlop ◽

Charlene Sathi ◽

Eileen Lam ◽

Brigitte McDonald ◽

...

Keyword(s):

Anorexia Nervosa ◽

Prefrontal Cortex ◽

Transcranial Magnetic Stimulation ◽

Magnetic Stimulation ◽

Repetitive Transcranial Magnetic Stimulation ◽

Trial Registration ◽

Angular Gyrus ◽

Open Label ◽

Compulsive Disorder ◽

Dorsomedial Prefrontal Cortex

Abstract Background Patients with anorexia nervosa (AN) face severe and chronic illness with high mortality rates, despite our best currently available conventional treatments. Repetitive transcranial magnetic stimulation (rTMS) has shown increasing efficacy in treatment-refractory cases across a variety of psychiatric disorders comorbid with AN, including major depression, Obsessive Compulsive Disorder (OCD), and Post traumatic Stress Disorder (PTSD). However, to date few studies have examined the effects of a course of rTMS on AN pathology itself. Methods Nineteen patients with AN underwent a 20–30 session open-label course of dorsomedial prefrontal rTMS for comorbid Major Depressive Disorder (MDD) ± PTSD. Resting-state functional MRI was acquired at baseline in 16/19 patients. Results Following treatment, significant improvements were seen in core AN pathology on the EDE global scale, and to a lesser extent on the shape and weight concerns subscales. Significant improvements in comorbid anxiety, and to a lesser extent depression, also ensued. The greatest improvements were seen in patients with lower baseline functional connectivity from the dorsomedial prefrontal cortex (DMPFC) target to regions in the right frontal pole and left angular gyrus. Conclusions Despite the limited size of this preliminary, open-label study, the results suggest that rTMS is safe in AN, and may be useful in addressing some core domains of AN pathology. Other targets may also be worth studying in this population, in future sham-controlled trials with larger sample sizes. Trial registration Trial registration ClinicalTrials.gov NCT04409704. Registered May 282,020. Retrospectively registered.

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Transcranial magnetic stimulation of the left angular gyrus during encoding does not impair associative memory performance

Cognitive Neuroscience ◽

10.1080/17588928.2018.1484723 ◽

2018 ◽

Vol 9 (3-4) ◽

pp. 127-138 ◽

Cited By ~ 2

Author(s):

Joshua D. Koen ◽

Preston P. Thakral ◽

Michael D. Rugg

Keyword(s):

Transcranial Magnetic Stimulation ◽

Associative Memory ◽

Magnetic Stimulation ◽

Memory Performance ◽

Angular Gyrus ◽

Left Angular Gyrus ◽

Stimulation Of

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Treatment of upper limb spasticity with inhibitory repetitive transcranial magnetic stimulation: A randomized placebo-controlled trial

Neurorehabilitation ◽

10.3233/nre-210088 ◽

2021 ◽

pp. 1-10

Author(s):

Anna Gottlieb ◽

Melanie Boltzmann ◽

Simone B. Schmidt ◽

Christoph Gutenbrunner ◽

Joachim K. Krauss ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Upper Limb ◽

Magnetic Stimulation ◽

Repetitive Transcranial Magnetic Stimulation ◽

Controlled Trial ◽

Angular Gyrus ◽

Double Blind ◽

Sensorimotor Network ◽

Positive Effects ◽

Limb Spasticity

BACKGROUND: Upper limb dysfunction is a frequent complication after stroke impairing outcome. Inhibitory repetitive transcranial magnetic stimulation (rTMS) applied over the contralesional hemisphere is supposed to enhance the positive effects of conventional rehabilitative treatment. OBJECTIVE: This double-blind randomized placebo-controlled trial investigated whether inhibitory rTMS as add-on to standard therapy improves upper limb spasticity. METHODS: Twenty-eight patients (aged 44 to 80 years) with unilateral stroke in the middle cerebral artery territory were analyzed. Participants were randomly assigned to inhibitory, low-frequency (LF-) rTMS (n = 14) or sham-rTMS (n = 14). The primary outcome measure was the spasticity grade, which was assessed with the Modified Ashworth Scale (MAS). In addition, the Fugl-Meyer-Assessment (FMA) for the upper extremity (UE) and a resting-state fMRI were performed to measure motor functions and the sensorimotor network, respectively. RESULTS: The MAS score was reduced in the LF-rTMS group only, whereas the FMA score improved in both groups over time. Regarding the fMRI data, both groups activated typical regions of the sensorimotor network. In the LF-rTMS group, however, connectivity to the left angular gyrus increased after treatment. CONCLUSION: Changes in functional connectivity in patients receiving inhibitory rTMS over the contralesional motor cortex suggest that processes of neuronal plasticity are stimulated.

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Interhemispheric interactions between the right angular gyrus and the left motor cortex: a transcranial magnetic stimulation study

Journal of Neurophysiology ◽

10.1152/jn.00642.2020 ◽

2021 ◽

Author(s):

Julianne Baarbé ◽

Michael Vesia ◽

Matt Brown ◽

Karlo J. Lizarraga ◽

Carolyn A Gunraj ◽

...

Keyword(s):

Transcranial Magnetic Stimulation ◽

Motor Cortex ◽

Magnetic Stimulation ◽

Posterior Parietal Cortex ◽

Short Interval ◽

Intracortical Inhibition ◽

Angular Gyrus ◽

Posterior Parietal ◽

The Right ◽

Left Angular Gyrus

The interconnection of the angular gyrus of right posterior parietal cortex (PPC) and the left motor cortex (LM1) is essential for goal-directed hand movements. Previous work with transcranial magnetic stimulation (TMS) showed that right PPC stimulation increases LM1 excitability but right PPC followed by left PPC-LM1 stimulation (LPPC-LM1) inhibits LM1 corticospinal output compared to LPPC-LM1 alone. It is not clear if right PPC-mediated inhibition of LPPC-LM1 is due to inhibition of left PPC or to combined effects of right and left PPC stimulation on LM1 excitability. We used paired-pulse TMS to study the extent to which combined right and left PPC stimulation, targeting the angular gyri, influences LM1 excitability. We tested 16 healthy subjects in five paired-pulsed TMS experiments using MRI-guided neuronavigation to target the angular gyri within PPC. We tested the effects of different right angular gyrus (RAG) and LM1 stimulation intensities on the influence of RAG on LM1 and on influence of left angular gyrus (LAG) on LM1 (LAG-LM1). We then tested the effects of RAG and LAG stimulation on LM1 short-interval intracortical facilitation(SICF), short-interval intracortical inhibition(SICI) and long-interval intracortical inhibition(LICI). The results revealed that RAG facilitated LM1, inhibited SICF and inhibited LAG-LM1. Combined RAG-LAG stimulation did not affect SICI but increased LICI. These experiments suggest that RAG-mediated inhibition of LAG-LM1 is related to inhibition of early I-wave activity and enhancement of GABAB receptor-mediated inhibition in LM1. The influence of RAG on LM1 likely involves ipsilateral connections from LAG to LM1 and heterotopic connections from RAG to LM1.

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