Can natural ways to stimulate the vagus nerve improve seizure control?

Musicotherapy mobile applications: what level of evidence and potential role in psychiatric care? A systematic review

Context

In our times of smartphone ubiquity, mobile applications are an inescapable daily life tool, including in health care. Music therapy has already proven its worth, notably in mental health. Hence, we were interested in the mobile app format for this type of therapy, its level of evidence, how to use it in daily psychiatric care and the leads for future research and innovation.

Method

This study carries out a systematic review of scientific literature of this topic on two search engines, PubMed and PubPsych, using these key-words: [(web-application) OR (web-app) OR (smartphone) OR (apps) OR (app)) AND ((music) OR (music therapy) OR (melody)].

Outcome

Out of a total of 282 studies found by keyword, 31 are included in this review. Several outcomes emerge. These studies relate to existing applications like Music Care, Calm or Unwind, on application prototypes or a potential use of music streaming applications on health care. They involve many different populations and clinical situations, including in hospital environments, for patients with chronic illnesses, different age ranges or for the general population. These musical interventions show a significant effect mainly for anxious symptoms, but also for depression, sleep disorders, pain and other psychiatric or psycho-somatic syndromes. These applications have no significant adverse effects.

Conclusion

This review shows that music therapy apps have several potentials for improving mental health care. It could assist psychiatric usual care and could potentially lower medication intake. Nevertheless, the studies on the topic are limited and recent but they open prospects for future research.

Mechanisms for survival: vagal control of goal-directed behavior

Survival is a fundamental physiological drive, and neural circuits have evolved to prioritize actions that meet the energy demands of the body. This fine-tuning of goal-directed actions based on metabolic states ('allostasis') is deeply rooted in our brain, and hindbrain nuclei orchestrate the vital communication between the brain and body through the vagus nerve. Despite mounting evidence for vagal control of allostatic behavior in animals, its broader function in humans is still contested. Based on stimulation studies, we propose that the vagal afferent pathway supports transitions between survival modes by gating the integration of ascending bodily signals, thereby regulating reward-seeking. By reconceptualizing vagal signals as catalysts for goal-directed behavior, our perspective opens new avenues for theory-driven translational work in mental disorders.

Modifying functional brain networks in focal epilepsy by manual visceral-osteopathic stimulation of the vagus nerve at the abdomen

Non-invasive transcutaneous vagus nerve stimulation elicits similar therapeutic effects as invasive vagus nerve stimulation, offering a potential treatment alternative for a wide range of diseases, including epilepsy. Here, we present a novel, non-invasive stimulation of the vagus nerve, which is performed manually viscero-osteopathically on the abdomen (voVNS). We explore the impact of short-term voVNS on various local and global characteristics of EEG-derived, large-scale evolving functional brain networks from a group of 20 subjects with and without epilepsy. We observe differential voVNS-mediated alterations of these characteristics that can be interpreted as a reconfiguration and modification of networks and their stability and robustness properties. Clearly, future studies are necessary to assess the impact of such a non-pharmaceutical intervention on clinical decision-making in the treatment of epilepsy. However, our findings may add to the current discussion on the importance of the gut-brain axis in health and disease. Clinical Trial Registration: https://drks.de/search/en/trial/DRKS00029914, identifier DRKS00029914.

Vagus nerve stimulation for conservative therapy-refractive epilepsy and depression

Numerous studies confirm that the vagus nerve stimulation (VNS) is an efficient, indirect neuromodulatory therapy with electrically induced current for epilepsy that cannot be treated by epilepsy surgery and is therapy-refractory and for drug therapy-refractory depression. VNS is an established, evidence-based and in the long-term cost-effective therapy in an interdisciplinary overall concept.Long-term data on the safety and tolerance of the method are available despite the heterogeneity of the patient populations. Stimulation-related side effects like hoarseness, paresthesia, cough or dyspnea depend on the stimulation strength and often decrease with continuing therapy duration in the following years. Stimulation-related side effects of VNS can be well influenced by modifying the stimulation parameters. Overall, the invasive vagus nerve stimulation may be considered as a safe and well-tolerated therapy option.For invasive and transcutaneous vagus nerve stimulation, antiepileptic and antidepressant as well as positive cognitive effects could be proven. In contrast to drugs, VNS has no negative effect on cognition. In many cases, an improvement of the quality of life is possible.iVNS therapy has a low probability of complete seizure-freedom in cases of focal and genetically generalized epilepsy. It must be considered as palliative therapy, which means that it does not lead to healing and requires the continuation of specific medication. The functional principle is a general reduction of the neuronal excitability. This effect is achieved by a slow increase of the effectiveness sometimes over several years. Responders are those patients who experience a 50% reduction of the seizure incidence. Some studies even reveal seizure-freedom in 20% of the cases. Currently, it is not possible to differentiate between potential responders and non-responders before therapy/implantation.The current technical developments of the iVNS generators of the new generation like closed-loop system (cardiac-based seizure detection, CBSD) reduce also the risk for SUDEP (sudden unexpected death in epilepsy patients), a very rare, lethal complication of epilepsies, beside the seizure severity.iVNS may deteriorate an existing sleep apnea syndrome and therefore requires possible therapy interruption during nighttime (day-night programming or magnet use) beside the close cooperation with sleep physicians.The evaluation of the numerous iVNS trials of the past two decades showed multiple positive effects on other immunological, cardiological, and gastroenterological diseases so that additional therapy indications may be expected depending on future study results. Currently, the vagus nerve stimulation is in the focus of research in the disciplines of psychology, immunology, cardiology as well as pain and plasticity research with the desired potential of future medical application.Beside invasive vagus nerve stimulation with implantation of an IPG and an electrode, also devices for transdermal and thus non-invasive vagus nerve stimulation have been developed during the last years. According to the data that are currently available, they are less effective with regard to the reduction of the seizure severity and duration in cases of therapy-refractory epilepsy and slightly less effective regarding the improvement of depression symptoms. In this context, studies are missing that confirm high evidence of effectiveness. The same is true for the other indications that have been mentioned like tinnitus, cephalgia, gastrointestinal complaints etc. Another disadvantage of transcutaneous vagus nerve stimulation is that the stimulators have to be applied actively by the patients and are not permanently active, in contrast to implanted iVNS therapy systems. So they are only intermittently active; furthermore, the therapy adherence is uncertain.

Toward Diverse or Standardized: A Systematic Review Identifying Transcutaneous Stimulation of Auricular Branch of the Vagus Nerve in Nomenclature

OBJECTIVES

After 20 years of development, there is confusion in the nomenclature of transcutaneous stimulation of the auricular branch of the vagus nerve (ABVN). We performed a systematic review of transcutaneous stimulation of ABVN in nomenclature.

MATERIALS AND METHODS

A systematic search of the literature was carried out, using the bibliographic search engine PubMed. The search covered articles published up until June 11, 2020. We recorded the full nomenclature and abbreviated nomenclature same or similar to transcutaneous stimulation of ABVN in the selected eligible studies, as well as the time and author information of this nomenclature.

RESULTS

From 261 studies, 67 full nomenclatures and 27 abbreviated nomenclatures were finally screened out, transcutaneous vagus nerve stimulation and tVNS are the most common nomenclature, accounting for 38.38% and 42.06%, respectively. In a total of 97 combinations of full nomenclatures and abbreviations, the most commonly used nomenclature for the combination of transcutaneous vagus nerve stimulation and tVNS, accounting for 30.28%. Interestingly, the combination of full nomenclatures and abbreviations is not always a one-to-one relationship, there are ten abbreviated nomenclatures corresponding to transcutaneous vagus nerve stimulation, and five full nomenclatures corresponding to tVNS. In addition, based on the analysis of the usage habits of nomenclature in 21 teams, it is found that only three teams have fixed habits, while other different teams or the same team do not always use the same nomenclature in their paper.

CONCLUSIONS

The phenomenon of confusion in the nomenclature of transcutaneous stimulation of ABVN is obvious and shows a trend of diversity. The nomenclature of transcutaneous stimulation of ABVN needs to become more standardized in the future.

From Precision Metapharmacology to Patient Empowerment: Delivery of Self-Care Practices for Epilepsy, Pain, Depression and Cancer Using Digital Health Technologies

To improve long-term outcomes of therapies for chronic diseases, health promotion and lifestyle modifications are the most promising and sustainable strategies. In addition, advances in digital technologies provide new opportunities to address limitations of drug-based treatments, such as medication non-adherence, adverse effects, toxicity, drug resistance, drug shortages, affordability, and accessibility. Pharmaceutical drugs and biologics can be combined with digital health technologies, including mobile medical apps (digital therapeutics), which offer additional clinical benefits and cost-effectiveness. Promises of drug+digital combination therapies are recognized by pharmaceutical and digital health companies, opening opportunities for integrating pharmacotherapies with non-pharmacological interventions (metapharmacology). Herein we present unique features of digital health technologies which can deliver personalized self-care modalities such as breathing exercises, mindfulness meditation, yoga, physical activity, adequate sleep, listening to preferred music, forgiveness and gratitude. Clinical studies reveal how aforementioned complimentary practices may support treatments of epilepsy, chronic pain, depression, cancer, and other chronic diseases. This article also describes how digital therapies delivering “medicinal” self-care and other non-pharmacological interventions can also be personalized by accounting for: 1) genetic risks for comorbidities, 2) adverse childhood experiences, 3) increased risks for viral infections such as seasonal influenza, or COVID-19, and 4) just-in-time stressful and traumatic circumstances. Development and implementation of personalized pharmacological-behavioral combination therapies (precision metapharmacology) require aligning priorities of key stakeholders including patients, research communities, healthcare industry, regulatory and funding agencies. In conclusion, digital technologies enable integration of pharmacotherapies with self-care, lifestyle interventions and patient empowerment, while concurrently advancing patient-centered care, integrative medicine and digital health ecosystems.

Effects of Meditation on Mental Health and Cardiovascular Balance in Caregivers

Background: Caring for a loved one can be rewarding but is also associated with substantial caregiver burden, developing mental outcomes and affecting happiness. The aim of this study was to determine the effects of a four-week, 16-h presential meditation program on physiological and psychological parameters and vagal nerve activity in high-burden caregivers, as compared to a control group. Methods: A non-randomized repeated-measures controlled clinical trial was conducted. Results: According to the ANCOVA results, the global happiness score (F = 297.42, p < 0.001) and the scores for all subscales were significantly higher in the experimental group than in the control group at 5 weeks. Anxiety levels were also significantly reduced in the experimental group (F = 24.92, p < 0.001), systolic (F = 16.23, p < 0.001) and diastolic blood (F = 34.39, p < 0.001) pressures, and the resting heart rate (F = 17.90, p < 0.05). HRV results revealed significant between-group differences in the HRV Index (F = 8.40, p < 0.05), SDNN (F = 13.59, p < 0.05), and RMSSD (F = 10.72, p < 0.05) in the time domain, and HF (F = 4.82 p < 0.05)) in the frequency domain, which were all improved in the experimental group after the meditation program. Conclusions: Meditation can be a useful therapy to enhance the mental health and autonomic nervous system balance of informal caregivers, improving symptoms of physical and mental overload.

Conditioned Variation in Heart Rate During Static Breath-Holds in the Bottlenose Dolphin (Tursiops truncatus)

Previous reports suggested the existence of direct somatic motor control over heart rate (f H) responses during diving in some marine mammals, as the result of a cognitive and/or learning process rather than being a reflexive response. This would be beneficial for O2 storage management, but would also allow ventilation-perfusion matching for selective gas exchange, where O2 and CO2 can be exchanged with minimal exchange of N2. Such a mechanism explains how air breathing marine vertebrates avoid diving related gas bubble formation during repeated dives, and how stress could interrupt this mechanism and cause excessive N2 exchange. To investigate the conditioned response, we measured the f H-response before and during static breath-holds in three bottlenose dolphins (Tursiops truncatus) when shown a visual symbol to perform either a long (LONG) or short (SHORT) breath-hold, or during a spontaneous breath-hold without a symbol (NS). The average f H (if Hstart), and the rate of change in f H (dif H/dt) during the first 20 s of the breath-hold differed between breath-hold types. In addition, the minimum instantaneous f H (if Hmin), and the average instantaneous f H during the last 10 s (if Hend) also differed between breath-hold types. The dif H/dt was greater, and the if Hstart, if Hmin, and if Hend were lower during a LONG as compared with either a SHORT, or an NS breath-hold (P < 0.05). Even though the NS breath-hold dives were longer in duration as compared with SHORT breath-hold dives, the dif H/dt was greater and the if Hstart, if Hmin, and if Hend were lower during the latter (P < 0.05). In addition, when the dolphin determined the breath-hold duration (NS), the f H was more variable within and between individuals and trials, suggesting a conditioned capacity to adjust the f H-response. These results suggest that dolphins have the capacity to selectively alter the f H-response during diving and provide evidence for significant cardiovascular plasticity in dolphins.

Effect of Heartfulness cleaning and meditation on heart rate variability

Background

Meditation has been a key component of eastern spiritual practices. Heartfulness meditation is a unique heart based system with key practices like cleaning and meditation aided by yogic transmission.

Objective

To study the effects of Heartfulness cleaning and meditation (guided by Heartfulness trainer) on heart rate variability (HRV), blood pressure (BP) and heart rate (HR).

Methods

A total of 30 participants (21 males, 9 females; age range 19–70 years, M = 45.1 years and SD = 12.7 years) participated in the study. HRV, BP and HR were studied before, during and after the three stages of rest, cleaning and meditation.

Results

There was significant effect of cleaning and meditation on normalized unit of power in low-frequency band (LFnu) for the three conditions [F (2, 87) = 9.98, p < 0.01] with mean values for baseline being 70.82 ± 14.55, cleaning being 55.62 ± 15.06 and meditation being 55.17 ± 16.63. There was also a significant effect of cleaning and meditation on normalized unit of power in high-frequency band (HFnu) [F (2, 87) = 7.31, p < 0.01] with mean values for baseline being 30.86 ± 16.51, cleaning being 44.37 ± 15.06 and meditation being 44.83 ± 16.63. Significant effect of cleaning and meditation was also seen for LF/HF [F (2, 87) = 4.98, p < 0.01] with mean values for baseline being 3.45 ± 3.40, cleaning being 1.63 ± 1.30 and meditation being 1.82 ± 2.19.

Conclusion

Heartfulness cleaning and meditation had a positive effect on sympathovagal balance.

Reinstatement of contextual conditioned anxiety in virtual reality and the effects of transcutaneous vagus nerve stimulation in humans

Since exposure therapy for anxiety disorders incorporates extinction of contextual anxiety, relapses may be due to reinstatement processes. Animal research demonstrated more stable extinction memory and less anxiety relapse due to vagus nerve stimulation (VNS). We report a valid human three-day context conditioning, extinction and return of anxiety protocol, which we used to examine effects of transcutaneous VNS (tVNS). Seventy-five healthy participants received electric stimuli (unconditioned stimuli, US) during acquisition (Day1) when guided through one virtual office (anxiety context, CTX+) but never in another (safety context, CTX-). During extinction (Day2), participants received tVNS, sham, or no stimulation and revisited both contexts without US delivery. On Day3, participants received three USs for reinstatement followed by a test phase. Successful acquisition, i.e. startle potentiation, lower valence, higher arousal, anxiety and contingency ratings in CTX+ versus CTX-, the disappearance of these effects during extinction, and successful reinstatement indicate validity of this paradigm. Interestingly, we found generalized reinstatement in startle responses and differential reinstatement in valence ratings. Altogether, our protocol serves as valid conditioning paradigm. Reinstatement effects indicate different anxiety networks underlying physiological versus verbal responses. However, tVNS did neither affect extinction nor reinstatement, which asks for validation and improvement of the stimulation protocol.

An acidosis-sparing ketogenic (ASK) diet to improve efficacy and reduce adverse effects in the treatment of refractory epilepsy

Diets that increase production of ketone bodies to provide alternative fuel for the brain are evolving from the classic ketogenic diet for epilepsy devised nearly a century ago. The classic ketogenic diet and its more recent variants all appear to have similar efficacy with approximately 50% of users showing a greater than 50% seizure reduction. They all require significant medical and dietetic support, and there are tolerability issues. A review suggests that low-grade chronic metabolic acidosis associated with ketosis is likely to be an important contributor to the short term and long term adverse effects of ketogenic diets. Recent studies, particularly with the characterization of the acid sensing ion channels, suggest that chronic metabolic acidosis may increase the propensity for seizures. It is also known that low-grade chronic metabolic acidosis has a broad range of negative health effects and an increased risk of early mortality in the general population. The modified ketogenic dietary treatment we propose is formulated to limit acidosis by measures that include monitoring protein intake and maximizing consumption of alkaline mineral-rich, low carbohydrate green vegetables. We hypothesize that this acidosis-sparing ketogenic diet is expected to be associated with less adverse effects and improved efficacy. A case history of life-long intractable epilepsy shows this diet to be a successful long-term strategy but, clearly, clinical studies are needed.