Effects of Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) on Verbal Working Memory, Word Fluency, and Verbal Episodic Memory in Healthy Young Adults

Sex differences in episodic memory have been reported. We investigate (1) the existence of sex differences in verbal and other episodic memory tasks in 54 countries, and (2) the association between the time- and country-specific social progress indicators (a) female to male ratio in education and labor force participation, (b) population education and employment, and (c) GDP per capita, and magnitude of sex differences in verbal episodic memory tasks. Data were retrieved from 612 studies, published 1973–2013. Results showed that females outperformed (Cohen’s d > 0) males in verbal (42 out of 45 countries) and other (28 out of 45 countries) episodic memory tasks. Although all three social progress indicators were, separately, positively associated with the female advantage in verbal episodic memory performance, only population education and employment remained significant when considering the social indicators together. Results suggest that women’s verbal episodic memory performance benefits more than men’s from education and employment.

Compromised Memory Function in Schizophrenia and Temporal Lobe Epilepsy

To investigate the combined effect of transcranial magnetic stimulation (TMS) and transcranial direct current stimulation on improving lower limb function in stroke patients. Randomized controlled trial. Subacute stroke patients. 169 post-stroke hemiplegia patients were randomly divided into 4 groups (control, transcranial direct current stimulation, transcutaneous auricular vagus nerve stimulation, and transcutaneous auricular vagus nerve stimulation combined with transcranial direct current stimulation) and evaluated using the Fugl-Meyer Assessment-Lower Extremity (FMA-LL), Timed Up-and-Go (TUG) test, Modified Barthel Index (MBI), Berg Balance Scale (BBS), gait parameters, and surface electromyography (sEMG). Significant improvements in FMA-LL, MBI, BBS, TUG, gait parameters, and sEMG were noted in the intervention groups compared with the control, with the transcutaneous auricular vagus nerve stimulation combined with transcranial direct current stimulation group showing the most pronounced improvements. Differences in some outcomes were also notable between the transcutaneous auricular vagus nerve stimulation and transcranial direct current stimulation groups. The combination of transcutaneous auricular vagus nerve stimulation and transcranial direct current stimulation effectively enhances gait, balance, and daily living activities in subacute stroke patients. These benefits are likely due to transcutaneous auricular vagus nerve stimulation activating the solitary and trigeminal nuclei and transcranial direct current stimulation stimulating the motor cortex. Wearable gait analysis systems and electromyography are valuable in clinical gait assessment for these patients.

This study investigated episodic and procedural memory performance in early and late pregnancy. Twenty-six women in the third trimester of pregnancy, 20 women in the first trimester of pregnancy, and 24 nonpregnant controls were administered a battery of verbal and visual episodic memory tasks and two procedural memory tasks. Results indicated that compared to controls, both pregnant groups had reduced scores on immediate and delayed verbal episodic memory tasks, but were unimpaired on visual and procedural memory tasks. Verbal memory differences could not be accounted for by mood state or attention; however, progesterone level accounted for a small amount of the variation. Although memory differences were minor, the perception of memory problems may have implications for everyday living for pregnant women.

The influence of estimated intelligence (group assessment of WAIS-R S) on sex differences in face recognition, as well as verbal and non-verbal episodic memory tasks was examined in 99 women and 88 men between 20 and 40 years of age. Results showed that men performed at a higher level than women on the WAIS-R S subtest Information, whereas the opposite was true for Digit symbol. Women performed at a higher level than men on the verbal episodic memory tasks and on face recognition, but there were no sex differences on the non-verbal episodic memory task. Estimated intelligence for both men and women was positively associated with most episodic memory measures, the exception being face recognition in women. In face recognition, there was no association to estimated intelligence, suggesting that face recognition performance in women is unrelated to several basic cognitive processes.

This systematic review aimed to evaluate the effect of transcutaneous auricular vagus nerve stimulation on heart rate variability and baroreflex sensitivity in healthy populations. PubMed, Scopus, the Cochrane Library, Embase, and Web of Science were systematically searched for controlled trials that examined the effects of transcutaneous auricular vagus nerve stimulation on heart rate variability parameters and baroreflex sensitivity in apparently healthy individuals. Two independent researchers screened the search results, extracted the data, and evaluated the quality of the included studies. From 2458 screened studies, 21 were included. Compared with baseline measures or the comparison group, significant changes in the standard deviation of NN intervals, the root mean square of successive RR intervals, the proportion of consecutive RR intervals that differ by more than 50ms, high-frequency power, low-frequency to high-frequency ratio, and low-frequency power were found in 86%, 75%, 69%, 47%, 36%, and 25% of the studies evaluating the effects of transcutaneous auricular vagus nerve stimulation on these indices, respectively. Baroreflex sensitivity was evaluated in six studies, of which a significant change was detected in only one. Some studies have shown that the worse the basic autonomic function, the better the response to transcutaneous auricular vagus nerve stimulation. The results were mixed, which may be mainly attributable to the heterogeneity of the study designs and stimulation delivery dosages. Thus, future studies with comparable designs are required to determine the optimal stimulation parameters and clarify the significance of autonomic indices as a reliable marker of neuromodulation responsiveness.

This study examined verbal working memory and language ability in 15 school-age children with autism using 3 verbal working memory tasks and 1 story recall task. Three measures of verbal working memory--nonword repetition, memory for digits span, and sentence imitation--were given to children with autism and age-matched controls. Verbal working memory measures were chosen to reflect increasing levels of cognitive-linguistic complexity. Story retelling was measured using The Renfrew Bus Story (J. Cowley & C. Glasgow, 1994) and was scored for the percentage of propositions recalled and the average utterance length. A profile of verbal working memory deficits was seen in children with autism, with poorer performance on more complex verbal memory tasks. Performance on the 3 verbal memory tasks was independent of articulation ability. For the group with autism, receptive vocabulary was associated with sentence imitation and story recall but not with nonword repetition or digits span. Sentence imitation was related to story recall, but the relationship disappeared when the effect of vocabulary was removed. Vocabulary and language processing demands affect the performance of children with autism on tasks of verbal memory and story retelling. Results are viewed within a connectionist framework of verbal working memory.

BackgroundTranscutaneous electrical nerve stimulation (TENS) is a non-invasive modality that utilizes electrical currents to modulate pain in populations with acute and chronic pain. TENS has been demonstrated to produce hypoalgesic effects in postoperative pain, fibromyalgia, knee osteoarthritis, and healthy subjects. Transcutaneous auricular vagus nerve stimulation (TaVNS) is a non-invasive modality that modulates the vagus nerve by stimulating its auricular branches. The effects of the combination of TENS and TaVNS on producing an analgesic response have not been studied. Considering that TENS and TaVNS both stimulate similar analgesic pathways but through different means of activation, we can hypothesize that a combination of both methods can produce a more pronounced analgesic response. Therefore, the objective of this study is to assess the hypoalgesic effect of a combination of TENS and TaVNS in pain-free subjects.Methods/designThe study will be a simple crossover design conducted at the University of Hartford. Subjects will be recruited from the University of Hartford population via oral communication, digital flyers, and posters on campus. Thirty participants will undergo two sessions in a crossover manner with one week in between. During one session, the participants will receive TENS with active TaVNS and the other session will be a placebo procedure (TENS with placebo TaVNS). The order of these sessions will be randomized. Importantly, the pressure pain threshold (PPT) and heat pain threshold (HPT) assessors will be blinded to the treatment category. For active TaVNS, a frequency of 25 Hz will be applied with a pulse duration of 200 µs. For placebo TaVNS, the intensity will be increased to a sensory level and then decreased to 0 mA. High-frequency TENS of 100 Hz will be applied in both sessions, with a pulse duration of 200 µsec, asymmetrical biphasic square waveform, and intensity of maximal tolerance without pain. TENS and TaVNS will be turned on for 30 min after a baseline measurement of outcomes. TENS and TaVNS will then be turned off, but the electrodes will remain on until completion of post-treatment assessment. Pressure pain threshold, heat pain threshold, blood pressure, oxygen saturation, and heart rate will be tested 4 times: Once pre-intervention, once during intervention, once immediately after the intervention, and once 15 min post-intervention. Statistical analysis of the data obtained will consider a significance level of p < 0.05.DiscussionThis study will provide evidence concerning the combined effects of TENS and TaVNS on pain threshold in pain-free participants. Based on the outcomes, a greater understanding of how TENS and TaVNS, when used in conjunction, can modulate pain pathways.Trial registrationClinicalTrials.gov NCT06361381. Registered on 09 April 2024.

Background &amp; objective: Low back pain is a common problem, especially in the young and middle-aged working people, and is often very resistant to the conventional management. We evaluated the impact of transcutaneous auricular vagus nerve stimulation (tVNS), applied in conjunction with an exercise treatment program, on disability in chronic low back pain patients.&#x0D; Methodology: The study was conducted from June to October 2022. Twenty-two patients aged 42.18 ± 9.91 y, with Numerical Pain Rating Scale (NPRS) score 5.64 ± 1.09 and Roland Morris Disability Questionnaire (RMDQ) score 10 ± 4.670, were randomly assigned to two groups. The control group received only exercise therapy (EXC group, n = 11), and the intervention group received exercise and tVNS therapy (EXC + tVNS group, n = 11). The primary outcome was RMDQ, measured before and after the intervention.&#x0D; Result: The mean RMDQ was significantly improved in both groups. In the intervention group the improvement was from 9.45 ± 4.44 to 2.18 ± 2.71 (P = 0.000), in the control group it was from 10.55 ± 5.05 to 2.36 ± 2.06 (P = 0.001). Inter-group comparison showed no significant difference. The effect size of the control group (2.12) was similar with the intervention group (1.98).&#x0D; Conclusion: Addition of 2-weeks tVNS to exercise therapy did not show superior effect on disability improvement compared to exercise only in chronic low back pain. Exercise alone was sufficient to improve the mean RMDQ.&#x0D; Abbreviations: CLBP: Chronic low back pain; EXC: Exercise; tVNS: Transcutaneous auricular vagus nerve stimulation; NPRS: Numerical pain rating scale; RMDQ: Roland Morris disability questionnaire&#x0D; Key words: Chronic low back pain; Disability; Exercise; Transcutaneous Auricular Vagus Nerve Stimulation&#x0D; Citation: Uzlifatin Y, Arfianti L, Wardhani IL, Hidayati HB, Melaniani S. Effect of transcutaneous auricular vagus nerve stimulation in addition to exercise on disability in chronic low back pain patients: a randomized controlled study. Anaesth. pain intensive care 2022;27(1):73−81; DOI: 10.35975/apic.v27i1.2084&#x0D; Received: December 07, 2022; Reviewed: December 28, 2022; Accepted: January 11, 2022

The role of verbal and visuospatial working memory in rule-based and information-integration category learning was examined. Previously, Maddox, Ashby, Ing, and Pickering found that a sequentially presented verbal working memory task did not affect information-integration learning, but disrupted rule-based learning when the rule was on the spatial frequency of a Gabor stimulus. This pattern was replicated in Experiment 1, in which the same category structures were used, but in which the verbal working memory task was replaced with a visuospatial analog. Experiment 2A examined rule-based learning on an oblique orientation and also found both verbal and visuospatial working memory tasks disrupting learning. Experiment 2B examined rule-based learning on a cardinal orientation and found a minimal effect of the verbal working memory task, but a large effect of the visuospatial working memory task. The conceptual significance of cardinal orientations and the role of visuospatial and verbal working memory in category learning are discussed.

In this study, we examined the impact of concurrent verbal and visuospatial working memory demands on performance of a visuospatial successive target detection task. Three hundred and four participants performed a visuospatial vigilance task while simultaneously performing either a spatial or verbal working memory task that either required a memory load during the vigil or did not require a memory load during the vigil. Perceptual sensitivity A' to vigilance target stimuli was reduced by concurrent memory load, both verbal and visuospatial. The decline in perceptual sensitivity to vigilance targets, the vigilance decrement, was steeper for a visuospatial memory task than a verbal memory task, regardless of concurrent memory load. Memory performance after vigilance detection trials was much lower for visuospatial than verbal items, even though memory performance before vigilance detection trials was higher for visuospatial than verbal items. Together, this indicates increased interference when a visuospatial vigilance task is paired with a visuospatial memory task, than when paired with a verbal memory task. Overall, the visuospatial and verbal working memory loads both impacted vigilance target detection, suggesting utilization of common executive resources. There may, however, be domain specific interference, and this may be exacerbated for two visuospatial tasks.

Healthcare workers (HCWs) have been significantly impacted by the pandemic. Elderly health care workers carry out a variety of duties at work and have years of clinical expertise. Anxiety and insomnia are among the more commonly encountered problems in senior physicians and other geriatric medical professional populations. The study aims to determine the effect of vagal nerve stimulation on anxiety and sleep disturbances among geriatric medical professionals. 42 participants were enrolled in this study based on the inclusion and exclusion criteria. The participants were divided into two groups using the closed envelope approach, and they took part in therapy sessions lasting 30 minutes, three times per week for a period of four weeks. The Experimental group A received non-invasive transcutaneous auricular vagal nerve stimulation (taVNS) and Control group A received Jacobson's progressive muscle relaxation technique. With a p value of 0.001, taVNS stimulation significantly improved sleep quality and reduced anxiety after 4 weeks. The post-intervention assessment revealed a highly significant improvement in Group A, with a T value of 251 (p < 0.001). The findings suggest that taVNS may be an effective intervention for addressing anxiety and sleep issues in geriatric medical professionals. These results contribute to the exploration of non-invasive strategies to enhance the well-being of healthcare professionals working in demanding environments.

Background and objectives: Myalgic encephalomyelitis (ME) is a complex, multi-system neurological condition. Dysfunction of the autonomic nervous system is a primary feature in diagnostic criteria, and management may include attempts to stimulate the parasympathetic nervous system. Transcutaneous auricular vagus nerve stimulation is an intervention that has been researched in neurological disorders, e.g. epilepsy, depression. While little evidence exists for its use in ME, this survey aims to explore the experiences and attitudes of people with ME to this intervention. Methods A 31-question online survey was devised and released on ME websites, Twitter and Facebook pages. People with ME read the information sheet and followed an online link to the survey. The survey was open for four weeks and all answers were anonymous. Results 116 responses were received. 56% of respondents reported favourable effects. Benefits of transcutaneous auricular vagus nerve stimulation were identified in relation to post exertional malaise, pain, gut problems, urinary problems, mental health, and the ability to leave the house. 67.2% of respondents would recommend the intervention to other people with ME. However, 4.3% would not recommend it and 6% reported it made them worse. 8.6% received support in setting up the device from healthcare workers. Conclusion The survey highlights that many people with ME experience significant benefits from using transcutaneous auricular vagus nerve stimulation; however due to potential negative effects there is the need for formal intervention studies to clearly identify safe parameters.

Excessive fear, worry and behavioral disturbances define anxiety, with particular significance attributed to vagal nerve, a crucial transmitter of information to the brain regions governing anxiety. Highlighting the importance of vagal nerve, transcutaneous auricular vagal nerve stimulation (TaVNS) emerges as a tolerable and safe technique. The success of non-invasive vagal nerve stimulation in alleviating anxiety underscores the pivotal role of the vagal nerve. The purpose of this study was to assess the effectiveness of physiotherapy interventions in mitigating anxiety among retired teachers during the COVID-19 pandemic, emphasizing the relevance of targeting the vagal nerve for improved mental well-being. 60 retired teachers diagnosed with anxiety were chosen through random allocation. Participants were divided into two groups: Group A (Experimental group) received transcutaneous auricular vagal nerve stimulation (TaVNS), and Group B (Control group) underwent the Jacobson relaxation technique. Intervention period spanned 4 weeks, with four sessions per week, lasting 30 minutes. The outcome measures included Generalized Anxiety Disorder-7 (GAD-7) questionnaire and salivary cortisol levels. Following the 4-week intervention, both groups exhibited a significant reduction in Generalized Anxiety Disorder-7 (GAD-7) scores and salivary cortisol levels (P < 0.001). Notably, Group A demonstrated a significantly higher effectiveness rate compared to Group B. The study concludes that transcutaneous auricular vagal nerve stimulation (TaVNS) is effective in reducing anxiety among retired teachers. Transcutaneous auricular vagal nerve stimulation (TaVNS) proves to be a powerful and effective intervention in alleviating anxiety among retired teachers, emphasizing its potential significance in enhancing mental well-being.

We report two individuals who successfully recovered from COVID-19-induced ARDS after being treated with transcutaneous auricular vagus nerve stimulation (taVNS). In the first case, taVNS was started after eleven hospital days of continual deterioration despite mechanical ventilation along with supportive therapy of steroids, antibiotics, and immunoglobulins. On the twelfth day of hospitalization, taVNS was begun four times daily, resulting in sudden improvement in oxygenation. There was a concomitant reduction of c-reactive protein from 109.6 μg/mL to 10 μg/mL. After nine days of taVNS therapy, the patient's improved respiratory function improved enough that she was able to be extubated. No additional treatments had been added or changed during this time. After twenty-seven days of hospitalization, the patient was discharged to home without supplemental oxygen. The second case involves taVNS therapy in the home setting. After nineteen days of progressive deterioration, the patient's oxygen saturation declined to 90% on room air before taVNS treatment was instituted. After tens days of taVNS treatment three times daily, his oxygen saturation had climbed to 97%, and by day 25 of VNS therapy, the patient felt he was fully recovered. taVNS is capable of improving regulation of the inflammatory response in other clinical conditions such as autoimmune disorders in humans and septic shock in animal models. We suggest that transcutaneous auricular vagus nerve stimulation is potent enough to improve the clinical course of COVID-19 associated ARDS because of its potential to minimize the clinical deterioration associated with the immunological surge known as the cytokine storm. taVNS is a safe and potentially efficacious treatment for COVID-19 ARDS.