Invasive Brain Stimulation Techniques Research Articles

Non-invasive Brain Stimulation for Post-COVID-19 Conditions: A Systematic Review

BackgroundAlongside the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, the number of patients with persistent symptoms following acute infection with SARS-CoV-2 is of concern. It is estimated that at least 65 million people worldwide meet criteria for what the World Health Organization (WHO) defines as "post-COVID-19 condition" — a multisystem disease comprising a wide range of symptoms. Effective treatments are lacking. In the present review, we aim to summarize the current evidence for the effectiveness of non-invasive or minimally invasive brain stimulation techniques in reducing symptoms of post-COVID-19. MethodsAfter pre-registration with PROSPERO, the review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Guidelines (PRISMA). The four electronic databases PubMed/MEDLINE, PsycINFO, Web of Science and Scopus were systematically searched for all relevant studies through April 2nd, 2024. Two independent investigators selected empirical papers that reported on the application of non- or minimally invasive brain stimulation in patients with post-COVID-19 conditions. ResultsA total of 19 studies were identified, one using transcutaneous vagus nerve stimulation (tVNS), another using transorbital alternating current stimulation (toACS), 6 studies on transcranial magnetic stimulation (TMS) and 11 studies on transcranial direct current stimulation (tDCS) for the treatment of post-COVID-19 symptoms. ConclusionsExisting studies report first promising results, illustrating improvement in clinical outcome parameters. Yet, the mechanistic understanding of post-COVID-19 and how brain stimulation techniques may be benefitial are limited. Directions for future research in the field are discussed.

Advances in Stroke Neurorehabilitation.

Stroke is one of the leading causes of disability worldwide despite recent advances in hyperacute interventions to lessen the initial impact of stroke. Stroke recovery therapies are crucial in reducing the long-term disability burden after stroke. Stroke recovery treatment options have rapidly expanded within the last decade, and we are in the dawn of an exciting era of multimodal therapeutic approaches to improve post-stroke recovery. In this narrative review, we highlighted various promising advances in treatment and technologies targeting stroke rehabilitation, including activity-based therapies, non-invasive and minimally invasive brain stimulation techniques, robotics-assisted therapies, brain-computer interfaces, pharmacological treatments, and cognitive therapies. These new therapies are targeted to enhance neural plasticity as well as provide an adequate dose of rehabilitation and improve adherence and participation. Novel activity-based therapies and telerehabilitation are promising tools to improve accessibility and provide adequate dosing. Multidisciplinary treatment models are crucial for post-stroke neurorehabilitation, and further adjuvant treatments with brain stimulation techniques and pharmacological agents should be considered to maximize the recovery. Among many challenges in the field, the heterogeneity of patients included in the study and the mixed methodologies and results across small-scale studies are the cardinal ones. Biomarker-driven individualized approaches will move the field forward, and so will large-scale clinical trials with a well-targeted patient population.

Comparative study between transcranial direct current and repetitive transcranial electromagnetic stimulation in the rehabilitation of primary fibromyalgia

Abstract Background Fibromyalgia syndrome (FMS) is a complex disorder where a widespread musculoskeletal pain (without a clear lesion basis) is associated with a great variety of symptoms including affective disturbances, central fatigue, cognitive dysfunction and even a particular skin reactivity to several chemical substances. Despite intense research effort, especially in the last years, the pathophysiology of the disease remains to be explained. The treatment recommendations were classified as pharmacological therapies, non-pharmacological treatments, and complementary non-pharmacological therapies. Also, particular interest has been raised by techniques able to perform effective modulation of brain areas through magnetic or electric currents applied to the scalp like transcranial magnetic and electrical stimulation such as direct current (TMS and tDCS). Objective: To compare the efficacy of Repetitive transcranial magnetic stimulation (r-TMS) and transcranial direct current stimulation (t-DCS) as non- invasive brain stimulation techniques in the rehabilitation of patients with primary (1ry) fibromyalgia (FM). Patients and Methods The present study included 30 patients with 1ry FM, equally divided into 2 groups. Group I included 15 patients who received 8 sessions of rTMS and Group II included 15 patients who received 8 sessions of anodal tDCS. Differences in visual analogue scale (VAS) of pain, tender point scale, Fibromyalgia Impact Questionnaire (FIQ) and Hospital Anxiety and Depression Scale (HADS) were assessed before and after completion of assigned treatment sessions. Results Pain VAS, tender point scale, FIQ and HADS showed significant decrease between baseline and follow-up assessments for both groups. Moreover, a significant change in all assessment scales was observed post treatment when compared between both groups with more significant improvement in the group received rTMS. Conclusion Both rTMS and tDCS techniques showed marked improvement in symptoms of pain, functional status and quality of life in patients with 1ry fibromyalgia. Both techniques can be considered as promising alternatives therapeutic options in the treatment of FM in order to reduce side effects of long-term use of drugs.

The Expanding Horizon of Neural Stimulation for Hyperkinetic Movement Disorders.

Novel methods of neural stimulation are transforming the management of hyperkinetic movement disorders. In this review the diversity of approach available is showcased. We first describe the most commonly used features that can be extracted from oscillatory activity of the central nervous system, and how these can be combined with an expanding range of non-invasive and invasive brain stimulation techniques. We then shift our focus to the periphery using tremor and Tourette's syndrome to illustrate the utility of peripheral biomarkers and interventions. Finally, we discuss current innovations which are changing the landscape of stimulation strategy by integrating technological advances and the use of machine learning to drive optimization.

Brain Stimulation to Modulate Food Intake and Eating Behavior.

Appetitive behaviors are mediated through homeostatic and reward signaling of brain circuits. There has been increasing interest in the use of neuromodulation techniques aimed at targeting brain regions such as the lateral prefrontal and subcortical regions associated with dysregulation of eating behaviors. Invasive brain stimulation techniques have demonstrated promising results in treating severe and enduring anorexia nervosa and morbid obesity. In addition, non-invasive techniques have been shown to successfully reduce food craving, hunger ratings, and calorie intake as well as binge/purge symptoms in eating disorders. Brain stimulation offers promising results for treating symptoms associated with eating disorders and modifying appetitive behaviors including craving and caloric consumption. Future research should focus on identifying optimal frequency and duration of stimulation and employ longitudinal studies to assess long-term effectiveness on clinical outcomes such as eating disorder symptomatology, weight loss, and sustained improvements in eating behaviors over time.

Neurostimulation

Neurostimulation modalities in psychiatric practice and research efforts use magnetic and electric fields to modulate neuronal functioning. Physicians have used these modalities since ancient history, but most modern brain stimulation treatments developed after the inception electroconvulsive therapy in 1937. Noninvasive brain stimulation generally refers to treatments that do not require surgery, such as electroconvulsive therapy, repetitive transcranial magnetic stimulation, and transcranial current stimulation. Conversely, deep brain stimulation and vagal nerve stimulation are the two most researched invasive brain stimulation modalities for psychiatric disorders. Treatment with repetitive transcranial magnetic stimulation has been shown to be effective for the treatment of resistant major depressive disorders but is less rapid acting and may be optimal for a different patient population as compared to electroconvulsive therapy. Research focused on transcranial direct current stimulation continues to expand, but its role in clinical psychiatric practice is currently not well defined. Despite mixed and, in some cases, disappointing results, invasive brain stimulation techniques such as deep brain stimulation and vagal nerve stimulation will likely continue to have an important role for certain treatment-resistant populations in psychiatric practice. This review examines the development, basic physiologic mechanisms, and evidence base of neurostimulation modalities in psychiatry. This review contains 4 figures, 6 tables and 38 references Key Words: deep brain stimulation, invasive, neurostimulation, noninvasive, transcranial direct current stimulation, transcranial electrical stimulation, transcranial magnetic stimulation, treatment-resistant depression, vagal nerve stimulation

Cerebellar neurophysiology in Gilles de la Tourette syndrome and its role as a target for therapeutic intervention.

Therapy resistance of approximately one-third of patients with Gilles de la Tourette syndrome (GTS) requires consideration of alternative therapeutic interventions. The article demonstrates the role of the cerebellum in neuropsychiatric disorders and GTS in particular, specifically its role in functions relating to motor and cognitive symptoms. Certain circuits in the cerebellum have been shown to undergo learning-induced changes during conditioning, with cells in the cortex of the cerebellum appearing to decrease their activity whilst those in deep nuclei seem to do the inverse. Evidence exists showing that abnormal excitability of the motor cortex via the cerebellum could be expected to participate in motor tics in GTS possibly due to aberrations in certain structures of involved circuits. The role of the cerebellum in learning and plasticity processes renders it a strategic and valuable structure to consider for brain stimulation when investigating potential treatment options for neuropsychiatric disorders such as GTS. This article puts forth the concept of using non-invasive and invasive brain stimulation techniques as a novel platform for non-pharmacological neuromodulation of GTS symptoms.

Brain Stimulation: New Vistas for the Exploration and Treatment of Tinnitus

Tinnitus, the perception of sounds or noise in the absence of auditory stimuli, is a frequent and often severely disabling symptom of different disorders of the auditory system. Attempts to develop evidence-based therapies have been thwarted by a poor understanding of the underlying pathophysiology. However, recent work points toward a pivotal role of maladaptive cortical reorganization in the generation and perpetuation of tinnitus. Changes in the representation of sounds, abnormalities of oscillatory activity, and hyperactivity in higher order areas of auditory processing have been linked with the perception of tinnitus. Brain stimulation techniques have entered the field and have opened exciting new perspectives for the modulation of dysfunctional brain activity. In this review, a comprehensive overview on the use of brain-stimulation techniques in the exploration and experimental treatment of tinnitus is provided. Noninvasive and invasive brain stimulation techniques, for example, transcranial magnetic stimulation (TMS), direct current stimulation (tDCS), and direct electrical cortical stimulation gave rise to a new line of investigation in tinnitus research. First, it has been shown that focal interference with presumably pathological cortical function can reduce tinnitus at least transiently. Second, the reduction of tinnitus-associated enhancement of cortical activity by neuronavigated TMS has been demonstrated to ameliorate tinnitus. Third, preliminary data suggest that repeated application of TMS or continuous cortical stimulation may lead to a longer lasting suppression of tinnitus. These proof of principle studies point toward a new option for the investigation and neurophysiology based treatment of tinnitus. Based on these findings, larger scale randomized clinical trials are needed to explore the efficacy of different brain stimulation techniques and parameters as well as the optimal target sites and treatment schedules. Particularly, a careful evaluation of clinical relevance under consideration of an adequate sham control and attention to possible unwanted side effects of these new interventions are indispensable.

Deep brain stimulation for treatment-resistant depression: A psychiatric perspective

Traditionally, the therapeutic approach to treatment-resistant depression (TRD) has relied on pharmacotherapy in various sequences and combinations, in addition to evidence-based psychotherapy or electroconvulsive therapy. Despite refinements to the existing therapeutic modalities, there remains a significant subpopulation of severely ill patients with refractory mood disorders who fail to achieve a clinical response despite aggressive psychosocial and biological treatments. Interest in the use of deep brain stimulation (DBS) for treatment-resistant psychiatric illness has emerged in recent years for a number of reasons: 1) as part of a general re-evaluation of both noninvasive and invasive brain stimulation techniques, 2) because of the demonstrated clinical efficacy of DBS for movement disorders, and 3) as a logical consequence of studies defining the functional neurocircuitry of several psychiatric disorders. This review will examine the progress of DBS in the treatment of Parkinson's disease and the potential implications for its use in TRD, as well as the role of the psychiatrist in selection and ongoing management of patients who receive this procedure.

The new invasive brain stimulation techniques in psychiatry

Chae et al. Rev Bras Psiquiatr 2001;23(2):100-9.

A review of the new minimally invasive brain stimulation techniques in psychiatry

New knowledge about the specific brain regions involved in neuropsychiatric disorders is rapidly evolving due to recent advances in functional neuroimaging techniques. The ability to stimulate the brain in awake alert adults without neurosurgery is a real advance that neuroscientists have long dreamed for. Several novel and minimally invasive techniques to stimulate the brain have recently developed. Among these newer somatic interventions, transcranial magnetic stimulation (TMS), vagus nerve stimulation (VNS) and deep brain stimulation (DBS) show promise as therapeutic tools in the treatment of neuropsychiatric disorders. This article reviews the history, methodology, and the future of these minimally invasive brain stimulation (MIBS) techniques and their emerging research and therapeutic applications in psychiatry

A SENSORY CORTICAL REPRESENTATION OF THE VAGUS NERVE: WITH A NOTE ON THE EFFECTS OF LOW BLOOD PRESSURE ON THE CORTICAL ELECTROGRAM

A SENSORY CORTICAL REPRESENTATION OF THE VAGUS NERVE: WITH A NOTE ON THE EFFECTS OF LOW BLOOD PRESSURE ON THE CORTICAL ELECTROGRAM