scholarly journals Excitatory Repetitive Transcranial Magnetic Stimulation Over Prefrontal Cortex in a Guinea Pig Model Ameliorates Tinnitus

2021 ◽  
Vol 15 ◽  
Author(s):  
Jack W. Zimdahl ◽  
Harrison Thomas ◽  
Samuel J. Bolland ◽  
Kerry Leggett ◽  
Kristin M. Barry ◽  
...  
Keyword(s):  
Prefrontal Cortex ◽  
Transcranial Magnetic Stimulation ◽  
Guinea Pig ◽  
Calcium Binding ◽  
Magnetic Stimulation ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Acoustic Trauma ◽  
Therapeutic Benefit ◽  
Auditory Thalamus ◽  
Guinea Pig Model

Tinnitus, a phantom auditory perception that can seriously affect quality of life, is generally triggered by cochlear trauma and associated with aberrant activity throughout the auditory pathways, often referred to as hyperactivity. Studies suggest that non-auditory structures, such as prefrontal cortex (PFC), may be involved in tinnitus generation, by affecting sensory gating in auditory thalamus, allowing hyperactivity to reach the cortex and lead to perception. Indeed, human studies have shown that repetitive transcranial magnetic stimulation (rTMS) of PFC can alleviate tinnitus. The current study investigated whether this therapeutic effect is achieved through inhibition of thalamic hyperactivity, comparing effects of two common clinical rTMS protocols with sham treatment, in a guinea pig tinnitus model. Animals underwent acoustic trauma and once tinnitus developed were treated with either intermittent theta burst stimulation (iTBS), 20 Hz rTMS, or sham rTMS (10 days, 10 min/day; weekdays only). Tinnitus was reassessed and extracellular recordings of spontaneous tonic and burst firing rates in auditory thalamus made. To verify effects in PFC, densities of neurons positive for calcium-binding proteins, calbindin and parvalbumin, were investigated using immunohistochemistry. Both rTMS protocols significantly reduced tinnitus compared to sham. However, spontaneous tonic firing decreased following 20 Hz stimulation and increased following iTBS in auditory thalamus. Burst rate was significantly different between 20 Hz and iTBS stimulation, and burst duration was increased only after 20 Hz treatment. Density of calbindin, but not parvalbumin positive neurons, was significantly increased in the most dorsal region of PFC indicating that rTMS directly affected PFC. Our results support the involvement of PFC in tinnitus modulation, and the therapeutic benefit of rTMS on PFC in treating tinnitus, but indicate this is not achieved solely by suppression of thalamic hyperactivity.

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

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.

Repetitive Transcranial Magnetic Stimulation Improves Depersonalization: A Case Report

CNS Spectrums ◽  
2004 ◽  
Vol 9 (5) ◽  
pp. 375-376 ◽  
Author(s):  
Alejandro M. Jiménez-Genchi
Keyword(s):  
Prefrontal Cortex ◽  
Case Report ◽  
Transcranial Magnetic Stimulation ◽  
Magnetic Stimulation ◽  
Dorsolateral Prefrontal Cortex ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Treatment Resistant ◽  
Depersonalization Disorder ◽  
Dorsolateral Prefrontal

AbstractDepersonalization disorder is a poorly understood and treatment-resistant condition. This report describes a patient with depersonalization disorder who underwent six sessions of repetitive transcranial magnetic stimulation on the left dorsolateral prefrontal cortex. Repetitive transcranial magnetic stimulation produced a 28% reduction on depersonalization scores.

Clinical effectiveness of repetitive transcranial magnetic stimulation treatment in children and adolescents with neurodevelopmental disorders: A systematic review

Autism ◽  
2019 ◽  
Vol 23 (7) ◽  
pp. 1614-1629 ◽  
Author(s):  
Fumi Masuda ◽  
Shinichiro Nakajima ◽  
Takahiro Miyazaki ◽  
Ryosuke Tarumi ◽  
Kamiyu Ogyu ◽  
...  
Keyword(s):  
Systematic Review ◽  
Prefrontal Cortex ◽  
Transcranial Magnetic Stimulation ◽  
Children And Adolescents ◽  
Neurodevelopmental Disorders ◽  
Magnetic Stimulation ◽  
Dorsolateral Prefrontal Cortex ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Low Frequency ◽  
Dorsolateral Prefrontal

Neurodevelopmental disorders, including autism spectrum disorder, are common in children and adolescents, but treatment strategies remain limited. Although repetitive transcranial magnetic stimulation has been studied for neurodevelopmental disorders, there is no clear consensus on its therapeutic effects. This systematic review examined literature on repetitive transcranial magnetic stimulation for children and adolescents with neurodevelopmental disorders published up to 2018 using the PubMed database. The search identified 264 articles and 14 articles met eligibility criteria. Twelve of these studies used conventional repetitive transcranial magnetic stimulation and two studies used theta burst stimulation. No severe adverse effects were reported in these studies. In patients with autism spectrum disorder, low-frequency repetitive transcranial magnetic stimulation and intermittent theta burst stimulation applied to the dorsolateral prefrontal cortex may have therapeutic effects on social functioning and repetitive behaviors. In patients with attention deficit/hyperactivity disorder, low-frequency repetitive transcranial magnetic stimulation applied to the left dorsolateral prefrontal cortex and high-frequency repetitive transcranial magnetic stimulation applied to the right dorsolateral prefrontal cortex may target inattention, hyperactivity, and impulsivity. In patients with tic disorders, low-frequency repetitive transcranial magnetic stimulation applied to the bilateral supplementary motor area improved tic symptom severity. This systematic review suggests that repetitive transcranial magnetic stimulation may be a promising intervention for children and adolescents with neurodevelopmental disorders. The results warrant further large randomized controlled trials of repetitive transcranial magnetic stimulation in children with neurodevelopmental disorders.

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