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Bömmer T, Schmidt LM, Meier K, Kricheldorff J, Stecher H, Herrmann CS, Thiel CM, Janitzky K, Witt K. Impact of Stimulation Duration in taVNS-Exploring Multiple Physiological and Cognitive Outcomes. Brain Sci 2024; 14:875. [PMID: 39335371 PMCID: PMC11430400 DOI: 10.3390/brainsci14090875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2024] [Revised: 08/21/2024] [Accepted: 08/22/2024] [Indexed: 09/30/2024] Open
Abstract
Transcutaneous auricular vagus nerve stimulation (taVNS) is a non-invasive neuromodulation technique that modulates the noradrenergic activity of the locus coeruleus (LC). Yet, there is still uncertainty about the most effective stimulation and reliable outcome parameters. In a double blind, sham-controlled study including a sample of healthy young individuals (N = 29), we compared a shorter (3.4 s) and a longer (30 s) stimulation duration and investigated the effects of taVNS (real vs. sham) on saliva samples (alpha amylase and cortisol concentration), pupil (pupillary light reflex and pupil size at rest) and EEG data (alpha and theta activity at rest, ERPs for No-Go signals), and cognitive tasks (Go/No-Go and Stop Signal Tasks). Salivary alpha amylase concentration was significantly increased in the real as compared to sham stimulation for the 30 s stimulation condition. In the 3.4 s stimulation condition, we found prolonged reaction times and increased error rates in the Go/No-Go task and increased maximum acceleration in the pupillary light reflex. For the other outcomes, no significant differences were found. Our results show that prolonged stimulation increases salivary alpha-amylase, which was expected from the functional properties of the LC. The finding of longer response times to short taVNS stimulation was not expected and cannot be explained by an increase in LC activity. We also discuss the difficulties in assessing pupil size as an expression of taVNS-mediated LC functional changes.
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Affiliation(s)
- Till Bömmer
- Department of Neurology, Carl von Ossietzky University, 26121 Oldenburg, Germany
- University Clinic for Neurology at the Evangelical Hospital, 26121 Oldenburg, Germany
| | - Luisa M Schmidt
- Department of Neurology, Carl von Ossietzky University, 26121 Oldenburg, Germany
- University Clinic for Neurology at the Evangelical Hospital, 26121 Oldenburg, Germany
| | - Katharina Meier
- Department of Neurology, Carl von Ossietzky University, 26121 Oldenburg, Germany
| | - Julius Kricheldorff
- Department of Neurology, Carl von Ossietzky University, 26121 Oldenburg, Germany
| | - Heiko Stecher
- Experimental Psychology Lab, Department of Psychology, Carl von Ossietzky University, 26129 Oldenburg, Germany
| | - Christoph S Herrmann
- Experimental Psychology Lab, Department of Psychology, Carl von Ossietzky University, 26129 Oldenburg, Germany
- Research Center Neurosensory Science, Carl von Ossietzky University, 26129 Oldenburg, Germany
| | - Christiane M Thiel
- Biological Psychology Lab, Department of Psychology, Carl von Ossietzky University, 26129 Oldenburg, Germany
| | - Kathrin Janitzky
- Department of Neurology, Carl von Ossietzky University, 26121 Oldenburg, Germany
- University Clinic for Neurology at the Evangelical Hospital, 26121 Oldenburg, Germany
| | - Karsten Witt
- Department of Neurology, Carl von Ossietzky University, 26121 Oldenburg, Germany
- University Clinic for Neurology at the Evangelical Hospital, 26121 Oldenburg, Germany
- Research Center Neurosensory Science, Carl von Ossietzky University, 26129 Oldenburg, Germany
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Berger A, Beckers E, Joris V, Duchêne G, Danthine V, Delinte N, Cakiroglu I, Sherif S, Morrison EIG, Sánchez AT, Macq B, Dricot L, Vandewalle G, El Tahry R. Locus coeruleus features are linked to vagus nerve stimulation response in drug-resistant epilepsy. Front Neurosci 2024; 18:1296161. [PMID: 38469571 PMCID: PMC10926962 DOI: 10.3389/fnins.2024.1296161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Accepted: 01/15/2024] [Indexed: 03/13/2024] Open
Abstract
The locus coeruleus-norepinephrine system is thought to be involved in the clinical effects of vagus nerve stimulation. This system is known to prevent seizure development and induce long-term plastic changes, particularly with the release of norepinephrine in the hippocampus. However, the requisites to become responder to the therapy and the mechanisms of action are still under investigation. Using MRI, we assessed the structural and functional characteristics of the locus coeruleus and microstructural properties of locus coeruleus-hippocampus white matter tracts in patients with drug-resistant epilepsy responding or not to the therapy. Twenty-three drug-resistant epileptic patients with cervical vagus nerve stimulation were recruited for this pilot study, including 13 responders or partial responders and 10 non-responders. A dedicated structural MRI acquisition allowed in vivo localization of the locus coeruleus and computation of its contrast (an accepted marker of LC integrity). Locus coeruleus activity was estimated using functional MRI during an auditory oddball task. Finally, multi-shell diffusion MRI was used to estimate the structural properties of locus coeruleus-hippocampus tracts. These characteristics were compared between responders/partial responders and non-responders and their association with therapy duration was also explored. In patients with a better response to the therapy, trends toward a lower activity and a higher contrast were found in the left medial and right caudal portions of the locus coeruleus, respectively. An increased locus coeruleus contrast, bilaterally over its medial portions, correlated with duration of the treatment. Finally, a higher integrity of locus coeruleus-hippocampus connections was found in patients with a better response to the treatment. These new insights into the neurobiology of vagus nerve stimulation may provide novel markers of the response to the treatment and may reflect neuroplasticity effects occurring in the brain following the implantation.
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Affiliation(s)
- Alexandre Berger
- Department of Clinical Neuroscience, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
- Synergia Medical SA, Mont-Saint-Guibert, Belgium
- Sleep and Chronobiology Laboratory, GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium
| | - Elise Beckers
- Sleep and Chronobiology Laboratory, GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium
- Faculty of Health, Medicine and Life Sciences, School for Mental Health and Neuroscience, Alzheimer’s Centre Limburg, Maastricht University, Maastricht, Netherlands
| | - Vincent Joris
- Department of Clinical Neuroscience, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
- Department of Neurosurgery, Cliniques Universitaires Saint-Luc, Brussels, Belgium
| | - Gaëtan Duchêne
- GE Center MR Applications, General Electric Healthcare, Diegem, Belgium
| | - Venethia Danthine
- Department of Clinical Neuroscience, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
| | - Nicolas Delinte
- Department of Clinical Neuroscience, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
- Institute of Information and Communication Technologies, Electronics and Applied Mathematics, Catholic University of Louvain, Louvain-la-Neuve, Belgium
| | - Inci Cakiroglu
- Department of Clinical Neuroscience, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
| | - Siya Sherif
- Sleep and Chronobiology Laboratory, GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium
| | | | - Andres Torres Sánchez
- Department of Clinical Neuroscience, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
- Innoviris, Brussels Institute for Research and Innovation, Brussels, Belgium
| | - Benoit Macq
- Institute of Information and Communication Technologies, Electronics and Applied Mathematics, Catholic University of Louvain, Louvain-la-Neuve, Belgium
| | - Laurence Dricot
- Department of Clinical Neuroscience, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
| | - Gilles Vandewalle
- Sleep and Chronobiology Laboratory, GIGA-Cyclotron Research Center-in vivo Imaging, University of Liège, Liège, Belgium
| | - Riëm El Tahry
- Department of Clinical Neuroscience, Institute of Neuroscience, Catholic University of Louvain, Brussels, Belgium
- Department of Neurology, Center for Refractory Epilepsy, Cliniques Universitaires Saint-Luc, Brussels, Belgium
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McHaney JR, Schuerman WL, Leonard MK, Chandrasekaran B. Transcutaneous Auricular Vagus Nerve Stimulation Modulates Performance but Not Pupil Size During Nonnative Speech Category Learning. JOURNAL OF SPEECH, LANGUAGE, AND HEARING RESEARCH : JSLHR 2023; 66:3825-3843. [PMID: 37652065 DOI: 10.1044/2023_jslhr-22-00596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
Abstract
PURPOSE Subthreshold transcutaneous auricular vagus nerve stimulation (taVNS) synchronized with behavioral training can selectively enhance nonnative speech category learning in adults. Prior work has demonstrated that behavioral performance increases when taVNS is paired with easier-to-learn Mandarin tone categories in native English listeners, relative to when taVNS is paired with harder-to-learn Mandarin tone categories or without taVNS. Mechanistically, this temporally precise plasticity has been attributed to noradrenergic modulation. However, prior work did not specifically utilize methodologies that indexed noradrenergic modulation and, therefore, was unable to explicitly test this hypothesis. Our goal for this study was to use pupillometry to gain mechanistic insights into taVNS behavioral effects. METHOD Thirty-eight participants learned to categorize Mandarin tones while pupillometry was recorded. In a double-blinded design, participants were divided into two taVNS groups that, as in the prior study, differed according to whether taVNS was paired with easier-to-learn tones or harder-to-learn tones. Learning performance and pupillary responses were measured using linear mixed-effects models. RESULTS We found that taVNS did not have any tone-specific or group behavioral or pupillary effects. However, in an exploratory analysis, we observed that taVNS did lead to faster rates of learning on trials paired with stimulation, particularly for those who were stimulated at lower amplitudes. CONCLUSIONS Our results suggest that pupillary responses may not be a reliable marker of locus coeruleus-norepinephrine system activity in humans. However, future research should systematically examine the effects of stimulation amplitude on both behavior and pupillary responses. SUPPLEMENTAL MATERIAL https://doi.org/10.23641/asha.24036666.
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Dolphin H, Dyer AH, Dukelow T, Finucane C, Commins S, Kennelly SP. Safety and feasibility of transcutaneous vagus nerve stimulation in mild cognitive impairment: VINCI-AD study protocol. BMC Neurol 2023; 23:289. [PMID: 37532979 PMCID: PMC10394887 DOI: 10.1186/s12883-023-03320-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Accepted: 07/05/2023] [Indexed: 08/04/2023] Open
Abstract
BACKGROUND Over 55 million adults are living with dementia globally, which is projected to reach 157 million by 2050. Mild cognitive impairment (MCI), a syndrome of memory impairment with intact activities of daily living, may precede dementia by several years. Around 5-15% of individuals with MCI convert to dementia annually. Novel treatments which delay progression of MCI to dementia are urgently needed. Transcutaneous vagal nerve stimulation (tVNS) is a non-invasive neuromodulation technique that targets the vagus nerve. Importantly, tVNS has been shown to improve cognition in healthy volunteers, but has not been extensively examined as a potential therapeutic approach in MCI. VINCI-AD will examine the safety and feasibility of tVNS in older adults with MCI. DESIGN VINCI-AD is an investigator-led, single-site, single-blind, sham-controlled crossover pilot study which aims to assess the safety and feasibility of tVNS in 40 participants with amnestic MCI. All participants will attend for three consecutive study visits during which they will be randomised to receive no stimulation (baseline), active tVNS stimulation (stimulation at cymba conchae of left ear) or sham tVNS stimulation (at earlobe). Safety will be primarily assessed by ascertainment of adverse events. Further safety assessment will examine the impact of acute tVNS on subjective (orthostatic symptoms), peripheral (finometry-based blood pressure) and central (assessed via Near Infrared Spectroscopy [NIRS]) haemodynamic responses to active stand. Feasibility will be determined using a custom-designed occupational assessment of device usability. Exploratory secondary analysis in VINCI-AD will examine the potential impact of acute tVNS on associative memory, spatial memory and inhibitory control to inform sample size estimates for future trials of tVNS in older adults with MCI. DISCUSSION VINCI-AD will report on the safety (adverse events/haemodynamic responses to active stand) and feasibility of tVNS as a potential therapeutic option in MCI. Detailed reporting of study eligibility and completion rates will be reported. Exploratory analysis will examine the potential cognitive benefits of acute tVNS on cognitive function in MCI to report potential effect sizes that may inform future clinical trials in this cohort. TRIAL REGISTRATION https://clinicaltrials.gov/ct2/show/NCT05514756 . Trial Registration Number NCT05514756 (24th August 2022 for this protocol, version 1.0.).
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Affiliation(s)
- Helena Dolphin
- Department of Medical Gerontology, Trinity College, Dublin 2, Dublin, Ireland.
- Institute of Memory and Cognition, Tallaght University Hospital, Dublin 24, Tallaght, Ireland.
- Age-Related Healthcare Department, Tallaght University Hospital, Tallaght, Ireland.
| | - Adam H Dyer
- Department of Medical Gerontology, Trinity College, Dublin 2, Dublin, Ireland
- Institute of Memory and Cognition, Tallaght University Hospital, Dublin 24, Tallaght, Ireland
| | - Tim Dukelow
- Department of Geriatric Medicine, Cork University Hospital, Cork, Ireland
| | - Ciaran Finucane
- Department of Medical Gerontology, Trinity College, Dublin 2, Dublin, Ireland
- Department of Medical Physics, St James's Hospital, Dublin, Ireland
| | - Sean Commins
- Department of Psychology, Maynooth University, Maynooth, Ireland
| | - Sean P Kennelly
- Department of Medical Gerontology, Trinity College, Dublin 2, Dublin, Ireland
- Institute of Memory and Cognition, Tallaght University Hospital, Dublin 24, Tallaght, Ireland
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Rufener KS, Wienke C, Salanje A, Haghikia A, Zaehle T. Effects of transcutaneous auricular vagus nerve stimulation paired with tones on electrophysiological markers of auditory perception. Brain Stimul 2023; 16:982-989. [PMID: 37336282 DOI: 10.1016/j.brs.2023.06.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Revised: 06/12/2023] [Accepted: 06/12/2023] [Indexed: 06/21/2023] Open
Abstract
BACKGROUND Transcutaneous auricular vagus nerve stimulation (taVNS) has been introduced as a non-invasive alternative to invasive vagus nerve stimulation (iVNS). While iVNS paired with tones has been highlighted as a potential effective therapy for the treatment of auditory disorders such as tinnitus, there is still scarce data available confirming the efficacy of non-invasive taVNS. Here, we assessed the effect of taVNS paired with acoustic stimuli on sensory-related electrophysiological responses. METHODS A total of 22 healthy participants were investigated with a taVNS tone-pairing paradigm using a within-subjects design. In a single session pure tones paired with either active taVNS or sham taVNS were repeatedly presented. Novel tones without electrical stimulation served as control condition. Auditory event related potentials and auditory cortex oscillations were compared before and after the tone pairing procedure between stimulation conditions. RESULTS From pre to post pairing, we observed a decrease in the N1 amplitude and in theta power to tones paired with sham taVNS while these electrophysiological measures remained stable for tones paired with active taVNS a pattern mirroring auditory sensory processing of novel, unpaired control tones. CONCLUSION Our results demonstrate the efficacy of a short-term application of non-invasive taVNS to modulate auditory processing in healthy individuals and, thereby, have potential implications for interventions in auditory processing deficits.
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Affiliation(s)
- Katharina S Rufener
- Department of Child and Adolescent Psychiatry and Psychotherapy, Otto-von-Guericke-University Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS), Otto-von-Guericke-University Magdeburg, Germany.
| | - Christian Wienke
- Department of Neurology, Otto-von-Guericke-University Magdeburg, Germany
| | - Alena Salanje
- Department of Neurology, Otto-von-Guericke-University Magdeburg, Germany
| | - Aiden Haghikia
- Department of Neurology, Otto-von-Guericke-University Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS), Otto-von-Guericke-University Magdeburg, Germany; German Center for Neurodegenerative Diseases (DZNE) Magdeburg, Germany
| | - Tino Zaehle
- Department of Neurology, Otto-von-Guericke-University Magdeburg, Germany; Center for Behavioral Brain Sciences (CBBS), Otto-von-Guericke-University Magdeburg, Germany
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Espinoza-Palavicino T, Mena-Chamorro P, Albayay J, Doussoulin A, Gálvez-García G. The use of transcutaneous Vagal Nerve Stimulation as an effective countermeasure for Simulator Adaptation Syndrome. APPLIED ERGONOMICS 2023; 107:103921. [PMID: 36341733 DOI: 10.1016/j.apergo.2022.103921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/05/2022] [Revised: 10/18/2022] [Accepted: 10/18/2022] [Indexed: 06/16/2023]
Abstract
This research focused on investigating the effectiveness of Transcutaneous Vagal Nerve Stimulation (tVNS) as compared to Galvanic Cutaneous Stimulation (GCS) at mitigating Simulator Adaptation Syndrome (SAS). Fifty drivers (mean age = 23.04 ± 17.71 years old, twenty-two men) participated in a driving simulation experiment. The total scores of the Simulator Sickness Questionnaire, head movements (body balance index), and driving performance variables were measured under five stimulation conditions: i) baseline (no stimulation delivered), ii) sham GCS, iii) sham tVNS, iv) active GCS, and v) active tNVS. The results showed that tVNS alleviated SAS and improved driving performance variables more effectively than GCS. We conclude that GCS and tVNS have similar neurological mechanisms to reduce SAS, providing possible explanations for the greater effectiveness of tVNS. We encourage the use of tVNS to decrease SAS.
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Affiliation(s)
- Tomás Espinoza-Palavicino
- -Departamento de Psicología, Universidad de La Frontera, Avenida Francisco Salazar 01145, 4780000, Temuco, Chile
| | - Patricio Mena-Chamorro
- -Departamento de Psicología, Universidad de La Frontera, Avenida Francisco Salazar 01145, 4780000, Temuco, Chile
| | - Javier Albayay
- -Center for Mind/Brain Sciences, University of Trento, Corso Bettini 31, 38068, Rovereto (TN), Italy
| | - Arlette Doussoulin
- -Departmento de Rehabilitación. Facultad de Medicina. Universidad de La Frontera, Avenida Francisco Salazar 01145, 4780000, Temuco, Chile
| | - Germán Gálvez-García
- -Departamento de Psicología, Universidad de La Frontera, Avenida Francisco Salazar 01145, 4780000, Temuco, Chile; - Departamento de Psicología Básica, Psicobiología y Metodología de las Ciencias del Comportamiento. Facultad de Psicología. Universidad de Salamanca. Campus Ciudad Jardín, 37005, Salamanca, Spain.
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7
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D'Agostini M, Burger AM, Franssen M, Perkovic A, Claes S, von Leupoldt A, Murphy PR, Van Diest I. Short bursts of transcutaneous auricular vagus nerve stimulation enhance evoked pupil dilation as a function of stimulation parameters. Cortex 2023; 159:233-253. [PMID: 36640622 DOI: 10.1016/j.cortex.2022.11.012] [Citation(s) in RCA: 16] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/28/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022]
Abstract
Transcutaneous auricular vagus nerve stimulation (taVNS) is a neurostimulatory technique hypothesised to enhance central noradrenaline. Currently, there is scarce evidence in support of a noradrenergic mechanism of taVNS and limited knowledge on its stimulation parameters (i.e., intensity and pulse width). Therefore, the present study aimed to test whether taVNS enhances pupil dilation, a noradrenergic biomarker, as a function of stimulation parameters. Forty-nine participants received sham (i.e., left ear earlobe) and taVNS (i.e., left ear cymba concha) stimulation in two separate sessions, in a counterbalanced order. We administered short bursts (5s) of seven stimulation settings varying as a function of pulse width and intensity and measured pupil size in parallel. Each stimulation setting was administered sixteen times in separate blocks. We expected short bursts of stimulation to elicit phasic noradrenergic activity as indexed by event-related pupil dilation and event-related temporal derivative. We hypothesised higher stimulation settings, quantified as the total charge per pulse (pulse width x intensity), to drive greater event-related pupil dilation and temporal derivative in the taVNS compared to sham condition. Specifically, we expected stimulation settings in the taVNS condition to be associated with a linear increase in event-related pupil dilation and temporal derivative. We found stimulation settings to linearly increase both pupil measures. In line with our hypothesis, the observed dose-dependent effect was stronger in the taVNS condition. We also found taVNS to elicit more intense and unpleasant sensations than sham stimulation. These results support the hypothesis of a noradrenergic mechanism of taVNS. However, future studies should disentangle whether stimulation elicited sensations mediate the effect of taVNS on evoked pupil dilation.
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Affiliation(s)
| | | | | | - Ana Perkovic
- Research Group Health Psychology, KU Leuven, Leuven, Belgium
| | - Stephan Claes
- The Mind Body Research Group, Department of Neuroscience, KU Leuven, Leuven, Belgium.
| | | | - Peter R Murphy
- Department of Psychology, Maynooth University, Co. Kildare, Ireland; Trinity College Institute of Neuroscience and School of Psychology, Trinity College Dublin, Ireland.
| | - Ilse Van Diest
- Research Group Health Psychology, KU Leuven, Leuven, Belgium.
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Maharjan A, Khwaounjoo P, Peng M, Cakmak YO. Non-contact neuromodulation of the human autonomic nervous system function via different odors: Sex, menstrual cycle, and odor dose- and duration-specific effects. Front Neurosci 2022; 16:950282. [PMID: 36312014 PMCID: PMC9596915 DOI: 10.3389/fnins.2022.950282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Accepted: 08/17/2022] [Indexed: 11/24/2022] Open
Abstract
In recent decades, it has been uncovered that the autonomic nervous system (ANS) can be influenced using non-contact neuromodulation via odor stimulation. Increasing parasympathetic-vagal activation of the ANS is integral to improving the sympathovagal balance between the sympathetic- and parasympathetic nervous systems, which is often imbalanced in several chronic inflammatory disorders, such as rheumatoid arthritis and inflammatory bowel diseases. Although research into olfactory stimulation has been observed on the ANS, it is still lacking in the exploration of odor concentration and odor-specific effects. This is particularly the case as research has not utilized specified tools, such as the olfactometer to provide precise odor delivery. Furthermore, no research has compared the results in separate sex cohorts to investigate the role of sex or the menstrual stage on the subsequent interactions. In this study, we investigated the olfactory stimulation effects of four natural odors (mushroom, lavender, jasmine, and rose) in three concentrations (low, moderate, and high) on the ANS. To observe activity from the ANS, we used an electrocardiogram (ECG) based heart rate variability (HRV) and eye-tracker technology (pupil diameter). We found for the first time in literature that there were acute dose- and duration-specific odor effects of odors on the ANS. We also found sex and menstrual cycle effects in this interaction. Furthermore, there were stark distinctions in sympathovagal activity dependent ANS activation (HRV) in comparison to the oculomotor nerve-parasympathetic/cervical sympathetic nerves dependent ANS responses (pupil diameter). Sympathovagal activity dependent HRV showed odor, sex, and menstrual-stage interactions in both divisions of the ANS while the pupil responses only indicated increased sympathetic activation. These results shed light on the use of odor-specific stimulation to modulate the ANS activity in the context of sex and the menstrual stage. Future studies should be performed using a chronic odor delivery design to investigate the long-term effects of odors on the ANS. Clinical trial registration Australian New Zealand Clinical Trials Registry, identifier [ACTRN12622000415707].
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Affiliation(s)
- Ashim Maharjan
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
| | - Prashanna Khwaounjoo
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
- Medical Technologies Centre of Research Excellence, Auckland, New Zealand
- Auckland Bioengineering Institute, University of Auckland, Auckland, New Zealand
| | - Mei Peng
- Sensory Neuroscience Laboratory, Department of Food Science, University of Otago, Dunedin, New Zealand
| | - Yusuf Ozgur Cakmak
- Department of Anatomy, School of Biomedical Sciences, University of Otago, Dunedin, New Zealand
- Medical Technologies Centre of Research Excellence, Auckland, New Zealand
- Brain Health Research Centre, Dunedin, New Zealand
- Centre for Bioengineering and Nanotechnology, Point of Care Technologies, University of Otago, Dunedin, New Zealand
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Dolphin H, Dukelow T, Finucane C, Commins S, McElwaine P, Kennelly SP. “The Wandering Nerve Linking Heart and Mind” – The Complementary Role of Transcutaneous Vagus Nerve Stimulation in Modulating Neuro-Cardiovascular and Cognitive Performance. Front Neurosci 2022; 16:897303. [PMID: 35784842 PMCID: PMC9245542 DOI: 10.3389/fnins.2022.897303] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2022] [Accepted: 05/30/2022] [Indexed: 11/13/2022] Open
Abstract
The vagus nerve is the longest nerve in the human body, providing afferent information about visceral sensation, integrity and somatic sensations to the CNS via brainstem nuclei to subcortical and cortical structures. Its efferent arm influences GI motility and secretion, cardiac ionotropy, chonotropy and heart rate variability, blood pressure responses, bronchoconstriction and modulates gag and cough responses via palatine and pharyngeal innervation. Vagus nerve stimulation has been utilized as a successful treatment for intractable epilepsy and treatment-resistant depression, and new non-invasive transcutaneous (t-VNS) devices offer equivalent therapeutic potential as invasive devices without the surgical risks. t-VNS offers exciting potential as a therapeutic intervention in cognitive decline and aging populations, classically affected by reduced cerebral perfusion by modulating both limbic and frontal cortical structures, regulating cerebral perfusion and improving parasympathetic modulation of the cardiovascular system. In this narrative review we summarize the research to date investigating the cognitive effects of VNS therapy, and its effects on neurocardiovascular stability.
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Affiliation(s)
- Helena Dolphin
- Department of Age-Related Healthcare, Tallaght University Hospital, Dublin, Ireland
- Department of Medical Gerontology, School of Medicine, Trinity College Dublin, Dublin, Ireland
- *Correspondence: Helena Dolphin,
| | - Tim Dukelow
- Department of Age-Related Healthcare, Tallaght University Hospital, Dublin, Ireland
| | - Ciaran Finucane
- Department of Medical Physics, St James’s Hospital, Dublin, Ireland
| | - Sean Commins
- Department of Psychology, Maynooth University, Maynooth, Ireland
| | - Paul McElwaine
- Department of Age-Related Healthcare, Tallaght University Hospital, Dublin, Ireland
- Department of Medical Gerontology, School of Medicine, Trinity College Dublin, Dublin, Ireland
| | - Sean P. Kennelly
- Department of Age-Related Healthcare, Tallaght University Hospital, Dublin, Ireland
- Department of Medical Gerontology, School of Medicine, Trinity College Dublin, Dublin, Ireland
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Klaming R, Simmons AN, Spadoni AD, Lerman I. Effects of Noninvasive Cervical Vagal Nerve Stimulation on Cognitive Performance But Not Brain Activation in Healthy Adults. Neuromodulation 2022; 25:424-432. [PMID: 35396072 PMCID: PMC8144242 DOI: 10.1111/ner.13313] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 10/19/2020] [Accepted: 10/20/2020] [Indexed: 01/13/2023]
Abstract
OBJECTIVES While preliminary evidence suggests that noninvasive vagal nerve stimulation (nVNS) may enhance cognition, to our knowledge, no study has directly assessed the effects of nVNS on brain function and cognitive performance in healthy individuals. The aim of this study was therefore to assess whether nVNS enhances complex visuospatial problem solving in a normative sample. Functional magnetic resonance imaging (fMRI) was used to examine underlying neural substrates. MATERIAL AND METHODS Participants received transcutaneous cervical nVNS (N = 15) or sham (N = 15) stimulation during a 3 T fMRI scan. Stimulation lasted for 2 min at 24 V for nVNS and at 4.5 V for sham. Subjects completed a matrix reasoning (MR) task in the scanner and a forced-choice recognition task outside the scanner. An analysis of variance (ANOVA) was used to assess group differences in cognitive performance. And linear mixed effects (LMEs) regression analysis was used to assess main and interaction effects of experimental groups, level of MR task difficulty, and recall accuracy on changes in blood oxygen level-dependent (BOLD) signal. RESULTS Subjects who received nVNS showed higher accuracy for both easy (p = 0.017) and hard (p = 0.013) items of the MR task, slower reaction times for hard items (p = 0.014), and fewer false negative errors during the forced-choice recognition task (p = 0.047). MR task difficulty related to increased activation in frontoparietal regions (p < 0.001). No difference between nVNS and sham stimulation was found on BOLD response during performance of the MR task. CONCLUSIONS We hypothesize that nVNS increased attention compared to sham, and that this effect led to enhanced executive functions, and consequently to better performance on visuospatial reasoning and recognition tasks. Results provide initial support that nVNS may be a low-risk, low-cost treatment for cognitive disorders.
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Affiliation(s)
- Ruth Klaming
- San Diego Department of Psychiatry, University of California, San Diego, CA, USA; VA San Diego Healthcare System, San Diego, CA, USA; San Diego State University, San Diego, CA, USA.
| | - Alan N Simmons
- San Diego Department of Psychiatry, University of California, San Diego, CA, USA; VA San Diego Healthcare System, San Diego, CA, USA
| | - Andrea D Spadoni
- San Diego Department of Psychiatry, University of California, San Diego, CA, USA; VA San Diego Healthcare System, San Diego, CA, USA
| | - Imanuel Lerman
- San Diego Department of Psychiatry, University of California, San Diego, CA, USA; VA San Diego Healthcare System, San Diego, CA, USA
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11
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Abstract
The human brain exhibits the remarkable ability to categorize speech sounds into distinct, meaningful percepts, even in challenging tasks like learning non-native speech categories in adulthood and hearing speech in noisy listening conditions. In these scenarios, there is substantial variability in perception and behavior, both across individual listeners and individual trials. While there has been extensive work characterizing stimulus-related and contextual factors that contribute to variability, recent advances in neuroscience are beginning to shed light on another potential source of variability that has not been explored in speech processing. Specifically, there are task-independent, moment-to-moment variations in neural activity in broadly-distributed cortical and subcortical networks that affect how a stimulus is perceived on a trial-by-trial basis. In this review, we discuss factors that affect speech sound learning and moment-to-moment variability in perception, particularly arousal states—neurotransmitter-dependent modulations of cortical activity. We propose that a more complete model of speech perception and learning should incorporate subcortically-mediated arousal states that alter behavior in ways that are distinct from, yet complementary to, top-down cognitive modulations. Finally, we discuss a novel neuromodulation technique, transcutaneous auricular vagus nerve stimulation (taVNS), which is particularly well-suited to investigating causal relationships between arousal mechanisms and performance in a variety of perceptual tasks. Together, these approaches provide novel testable hypotheses for explaining variability in classically challenging tasks, including non-native speech sound learning.
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12
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D'Agostini M, Burger AM, Villca Ponce G, Claes S, von Leupoldt A, Van Diest I. No evidence for a modulating effect of continuous transcutaneous auricular vagus nerve stimulation on markers of noradrenergic activity. Psychophysiology 2022; 59:e13984. [PMID: 34990045 DOI: 10.1111/psyp.13984] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2021] [Revised: 11/12/2021] [Accepted: 11/15/2021] [Indexed: 01/22/2023]
Abstract
Although transcutaneous auricular vagus nerve stimulation (taVNS) is thought to increase central noradrenergic activity, findings supporting such mechanism are scarce and inconsistent. This study aimed to investigate whether taVNS modulates indirect markers of phasic and tonic noradrenergic activity. Sixty-six healthy participants performed a novelty auditory oddball task twice on separate days: once while receiving taVNS (left cymba concha), once during sham (left earlobe) stimulation. To maximize potential effects, the stimulation was delivered continuously (frequency: 25 Hz; width: 250 μs) at an intensity individually calibrated to the maximal level below pain threshold. The stimulation was administered 10 min before the oddball task and maintained throughout the session. Event-related pupil dilation (ERPD) to target stimuli and pre-stimulus baseline pupil size were assessed during the oddball task as markers of phasic and tonic noradrenergic activity, respectively. Prior to and at the end of stimulation, tonic pupil size at rest, cortisol, and salivary alpha-amylase were assessed as markers of tonic noradrenergic activity. Finally, we explored the effect of taVNS on cardiac vagal activity, respiratory rate, and salivary flow rate. Results showed a greater ERPD to both target and novelty compared to standard stimuli in the oddball task. In contrast to our hypotheses, taVNS did not impact any of the tested markers. Our findings strongly suggest that continuous stimulation of the cymba concha with the tested stimulation parameters is ineffective to increase noradrenergic activity via a vagal pathway.
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Affiliation(s)
| | | | | | - Stephan Claes
- The Mind Body Research Group, Department of Neuroscience, KU Leuven, Leuven, Belgium
| | | | - Ilse Van Diest
- Research Group Health Psychology, KU Leuven, Leuven, Belgium
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13
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Berger A, Vespa S, Dricot L, Dumoulin M, Iachim E, Doguet P, Vandewalle G, El Tahry R. How Is the Norepinephrine System Involved in the Antiepileptic Effects of Vagus Nerve Stimulation? Front Neurosci 2021; 15:790943. [PMID: 34924947 PMCID: PMC8675889 DOI: 10.3389/fnins.2021.790943] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2021] [Accepted: 11/11/2021] [Indexed: 01/09/2023] Open
Abstract
Vagus Nerve Stimulation (VNS) is an adjunctive treatment for patients suffering from inoperable drug-resistant epilepsy. Although a complete understanding of the mediators involved in the antiepileptic effects of VNS and their complex interactions is lacking, VNS is known to trigger the release of neurotransmitters that have seizure-suppressing effects. In particular, norepinephrine (NE) is a neurotransmitter that has been associated with the clinical effects of VNS by preventing seizure development and by inducing long-term plastic changes that could restore a normal function of the brain circuitry. However, the biological requisites to become responder to VNS are still unknown. In this review, we report evidence of the critical involvement of NE in the antiepileptic effects of VNS in rodents and humans. Moreover, we emphasize the hypothesis that the functional integrity of the noradrenergic system could be a determining factor to obtain clinical benefits from the therapy. Finally, encouraging avenues of research involving NE in VNS treatment are discussed. These could lead to the personalization of the stimulation parameters to maximize the antiepileptic effects and potentially improve the response rate to the therapy.
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Affiliation(s)
- Alexandre Berger
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium.,Synergia Medical SA, Mont-Saint-Guibert, Belgium.,GIGA-Cyclotron Research Center-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Simone Vespa
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Laurence Dricot
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Manon Dumoulin
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium
| | - Evelina Iachim
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium.,Department of Pediatric Neurology, Carol Davila University of Medicine and Pharmacy, Bucharest, Romania
| | | | - Gilles Vandewalle
- GIGA-Cyclotron Research Center-In Vivo Imaging, University of Liège, Liège, Belgium
| | - Riëm El Tahry
- Institute of Neuroscience, Université catholique de Louvain, Brussels, Belgium.,Center for Refractory Epilepsy, Department of Neurology, Cliniques Universitaires Saint-Luc, Brussels, Belgium
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14
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Ruhnau P, Zaehle T. Transcranial Auricular Vagus Nerve Stimulation (taVNS) and Ear-EEG: Potential for Closed-Loop Portable Non-invasive Brain Stimulation. Front Hum Neurosci 2021; 15:699473. [PMID: 34194308 PMCID: PMC8236702 DOI: 10.3389/fnhum.2021.699473] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 05/21/2021] [Indexed: 11/17/2022] Open
Abstract
No matter how hard we concentrate, our attention fluctuates – a fact that greatly affects our success in completing a current task. Here, we review work from two methods that, in a closed-loop manner, have the potential to ameliorate these fluctuations. Ear-EEG can measure electric brain activity from areas in or around the ear, using small and thus portable hardware. It has been shown to capture the state of attention with high temporal resolution. Transcutaneous auricular vagus nerve stimulation (taVNS) comes with the same advantages (small and light) and critically current research suggests that it is possible to influence ongoing brain activity that has been linked to attention. Following the review of current work on ear-EEG and taVNS we suggest that a combination of the two methods in a closed-loop system could serve as a potential application to modulate attention.
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Affiliation(s)
- Philipp Ruhnau
- Department of Neurology, Otto von Guericke University, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany
| | - Tino Zaehle
- Department of Neurology, Otto von Guericke University, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Otto von Guericke University, Magdeburg, Germany
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15
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Capone F, Motolese F, Di Zazzo A, Antonini M, Magliozzi A, Rossi M, Marano M, Pilato F, Musumeci G, Coassin M, Di Lazzaro V. The effects of transcutaneous auricular vagal nerve stimulation on pupil size. Clin Neurophysiol 2021; 132:1859-1865. [PMID: 34147923 DOI: 10.1016/j.clinph.2021.05.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2020] [Revised: 04/28/2021] [Accepted: 05/10/2021] [Indexed: 10/21/2022]
Abstract
OBJECTIVE Mechanisms of action and optimal stimulation parameters of transcutaneous auricular vagus nerve stimulation (taVNS) are currently unknown. Pupil size has gained attention as a promising biomarker of vagal activation in different studies on animal models. The aim of this study is to investigate the effects of taVNS on pupil diameter in healthy subjects. METHODS All subjects received taVNS at the left external acoustic meatus and control stimulation at the left earlobe during the same experimental session. Different intensities (0.5 mA; 1.0 mA; 2.0 mA; 3.0 mA) for both conditions were tested. Tonic pupil size was recorded in both eyes at baseline and during each stimulation using an infrared-automated pupillometer in three different illuminance conditions (scotopic, mesopic, photopic). RESULTS In scotopic illuminance condition, a significant interaction between intensity and condition (real vs control) was found for the left eye. Post-Hoc analysis showed that during real taVNS at 2 mA, pupil size was significantly larger in comparison to baseline and 2 mA control stimulation. CONCLUSIONS Our study demonstrates that taVNS induces pupil dilation under specific illuminance conditions and at specific stimulation intensity. SIGNIFICANCE The effects of taVNS are strictly dependent on technical aspects, such as stimulation parameters and experimental set-up.
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Affiliation(s)
- Fioravante Capone
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy; NeXT: Neurophysiology and Neuroengineering of Human-Technology Interaction Research Unit, Campus Bio-Medico University, Rome, Italy.
| | - Francesco Motolese
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy; NeXT: Neurophysiology and Neuroengineering of Human-Technology Interaction Research Unit, Campus Bio-Medico University, Rome, Italy
| | - Antonio Di Zazzo
- Ophthalmology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Marco Antonini
- Ophthalmology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Alessandro Magliozzi
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Mariagrazia Rossi
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Massimo Marano
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Fabio Pilato
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Gabriella Musumeci
- NeXT: Neurophysiology and Neuroengineering of Human-Technology Interaction Research Unit, Campus Bio-Medico University, Rome, Italy
| | - Marco Coassin
- Ophthalmology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Vincenzo Di Lazzaro
- Neurology, Neurophysiology and Neurobiology Unit, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
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16
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Transcutaneous vagus nerve stimulation in patients with attention-deficit/hyperactivity disorder: A viable option? PROGRESS IN BRAIN RESEARCH 2021; 264:171-190. [PMID: 34167655 DOI: 10.1016/bs.pbr.2021.03.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Individuals with attention-deficit/hyperactivity disorder (ADHD) suffer from a range of cognitive and behavioral problems that severely impair their educational and occupational attainment. ADHD symptoms have been linked to structural and functional changes within and between different brain regions, particularly the prefrontal cortex. At the system level, reduced availability of the neurotransmitters dopamine (DA) and norepinephrine (NE) but also γ-aminobutyric acid (GABA) have been repeatedly demonstrated. Recently, non-invasive brain stimulation (NIBS) techniques have been explored as treatment alternatives to alter dysfunctional activation patterns in specified brain areas or networks. In the current paper, we introduce transcutaneous vagus nerve stimulation (tVNS) as a systemic approach to directly affect NE and GABA neurotransmission. TVNS is a non-drug intervention with low risk and proven efficacy in improving cognitive particularly executive functions. It is easy to apply and therefore well-suited to provide home-based or mobile treatment options allowing a significant increase in treatment intensity and providing easier access to medical care for individuals who are unable to regularly visit a clinician. We describe in detail the underlying mechanisms of tVNS and current fields of application and discuss its potential as an adjuvant treatment for ADHD.
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17
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Farmer AD, Strzelczyk A, Finisguerra A, Gourine AV, Gharabaghi A, Hasan A, Burger AM, Jaramillo AM, Mertens A, Majid A, Verkuil B, Badran BW, Ventura-Bort C, Gaul C, Beste C, Warren CM, Quintana DS, Hämmerer D, Freri E, Frangos E, Tobaldini E, Kaniusas E, Rosenow F, Capone F, Panetsos F, Ackland GL, Kaithwas G, O'Leary GH, Genheimer H, Jacobs HIL, Van Diest I, Schoenen J, Redgrave J, Fang J, Deuchars J, Széles JC, Thayer JF, More K, Vonck K, Steenbergen L, Vianna LC, McTeague LM, Ludwig M, Veldhuizen MG, De Couck M, Casazza M, Keute M, Bikson M, Andreatta M, D'Agostini M, Weymar M, Betts M, Prigge M, Kaess M, Roden M, Thai M, Schuster NM, Montano N, Hansen N, Kroemer NB, Rong P, Fischer R, Howland RH, Sclocco R, Sellaro R, Garcia RG, Bauer S, Gancheva S, Stavrakis S, Kampusch S, Deuchars SA, Wehner S, Laborde S, Usichenko T, Polak T, Zaehle T, Borges U, Teckentrup V, Jandackova VK, Napadow V, Koenig J. International Consensus Based Review and Recommendations for Minimum Reporting Standards in Research on Transcutaneous Vagus Nerve Stimulation (Version 2020). Front Hum Neurosci 2021; 14:568051. [PMID: 33854421 PMCID: PMC8040977 DOI: 10.3389/fnhum.2020.568051] [Citation(s) in RCA: 141] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 09/01/2020] [Indexed: 12/18/2022] Open
Abstract
Given its non-invasive nature, there is increasing interest in the use of transcutaneous vagus nerve stimulation (tVNS) across basic, translational and clinical research. Contemporaneously, tVNS can be achieved by stimulating either the auricular branch or the cervical bundle of the vagus nerve, referred to as transcutaneous auricular vagus nerve stimulation(VNS) and transcutaneous cervical VNS, respectively. In order to advance the field in a systematic manner, studies using these technologies need to adequately report sufficient methodological detail to enable comparison of results between studies, replication of studies, as well as enhancing study participant safety. We systematically reviewed the existing tVNS literature to evaluate current reporting practices. Based on this review, and consensus among participating authors, we propose a set of minimal reporting items to guide future tVNS studies. The suggested items address specific technical aspects of the device and stimulation parameters. We also cover general recommendations including inclusion and exclusion criteria for participants, outcome parameters and the detailed reporting of side effects. Furthermore, we review strategies used to identify the optimal stimulation parameters for a given research setting and summarize ongoing developments in animal research with potential implications for the application of tVNS in humans. Finally, we discuss the potential of tVNS in future research as well as the associated challenges across several disciplines in research and clinical practice.
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Affiliation(s)
- Adam D. Farmer
- Department of Gastroenterology, University Hospitals of North Midlands NHS Trust, Stoke on Trent, United Kingdom
| | - Adam Strzelczyk
- Department of Neurology, Epilepsy Center Frankfurt Rhine-Main, Goethe-University Frankfurt, Frankfurt am Main, Germany
| | | | - Alexander V. Gourine
- Department of Neuroscience, Physiology and Pharmacology, Centre for Cardiovascular and Metabolic Neuroscience, University College London, London, United Kingdom
| | - Alireza Gharabaghi
- Institute for Neuromodulation and Neurotechnology, University Hospital and University of Tuebingen, Tuebingen, Germany
| | - Alkomiet Hasan
- Department of Psychiatry, Psychotherapy and Psychosomatics, Medical Faculty, University of Augsburg, Augsburg, Germany
- Department of Psychiatry and Psychotherapy, University Hospital, LMU Munich, Munich, Germany
| | - Andreas M. Burger
- Laboratory for Biological Psychology, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium
| | | | - Ann Mertens
- Department of Neurology, Institute for Neuroscience, 4Brain, Ghent University Hospital, Gent, Belgium
| | - Arshad Majid
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, United Kingdom
| | - Bart Verkuil
- Clinical Psychology and the Leiden Institute of Brain and Cognition, Leiden University, Leiden, Netherlands
| | - Bashar W. Badran
- Department of Psychiatry, Medical University of South Carolina, Charleston, SC, United States
| | - Carlos Ventura-Bort
- Department of Biological Psychology and Affective Science, Faculty of Human Sciences, University of Potsdam, Potsdam, Germany
| | - Charly Gaul
- Migraine and Headache Clinic Koenigstein, Königstein im Taunus, Germany
| | - Christian Beste
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Dresden, Germany
| | | | - Daniel S. Quintana
- NORMENT, Division of Mental Health and Addiction, University of Oslo and Oslo University Hospital, Oslo, Norway
- Department of Psychology, University of Oslo, Oslo, Norway
- KG Jebsen Centre for Neurodevelopmental Disorders, University of Oslo, Oslo, Norway
| | - Dorothea Hämmerer
- Medical Faculty, Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke University, Magdeburg, Germany
- Institute of Cognitive Neuroscience, University College London, London, United Kingdom
- Center for Behavioral Brain Sciences Magdeburg (CBBS), Otto-von-Guericke University, Magdeburg, Germany
| | - Elena Freri
- Department of Pediatric Neuroscience, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy
| | - Eleni Frangos
- Pain and Integrative Neuroscience Branch, National Center for Complementary and Integrative Health, NIH, Bethesda, MD, United States
| | - Eleonora Tobaldini
- Department of Internal Medicine, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Eugenijus Kaniusas
- Institute of Electrodynamics, Microwave and Circuit Engineering, TU Wien, Vienna, Austria
- SzeleSTIM GmbH, Vienna, Austria
| | - Felix Rosenow
- Department of Neurology, Epilepsy Center Frankfurt Rhine-Main, Goethe-University Frankfurt, Frankfurt am Main, Germany
| | - Fioravante Capone
- Unit of Neurology, Neurophysiology, Neurobiology, Department of Medicine, Università Campus Bio-Medico di Roma, Rome, Italy
| | - Fivos Panetsos
- Faculty of Biology and Faculty of Optics, Complutense University of Madrid and Institute for Health Research, San Carlos Clinical Hospital (IdISSC), Madrid, Spain
| | - Gareth L. Ackland
- Translational Medicine and Therapeutics, Barts and The London School of Medicine and Dentistry, William Harvey Research Institute, Queen Mary University of London, London, United Kingdom
| | - Gaurav Kaithwas
- Department of Pharmaceutical Sciences, School of Biosciences and Biotechnology, Babasaheb Bhimrao Ambedkar University (A Central University), Lucknow, India
| | - Georgia H. O'Leary
- Department of Psychiatry, Medical University of South Carolina, Charleston, SC, United States
| | - Hannah Genheimer
- Department of Biological Psychology, Clinical Psychology and Psychotherapy, University of Würzburg, Würzburg, Germany
| | - Heidi I. L. Jacobs
- Division of Nuclear Medicine and Molecular Imaging, Department of Radiology, Massachusetts General Hospital and Harvard Medical School, Boston, MA, United States
- Faculty of Health, Medicine and Life Sciences, School for Mental Health and Neuroscience, Alzheimer Centre Limburg, Maastricht University, Maastricht, Netherlands
| | - Ilse Van Diest
- Research Group Health Psychology, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium
| | - Jean Schoenen
- Headache Research Unit, Department of Neurology-Citadelle Hospital, University of Liège, Liège, Belgium
| | - Jessica Redgrave
- Sheffield Institute for Translational Neuroscience (SITraN), University of Sheffield, Sheffield, United Kingdom
| | - Jiliang Fang
- Functional Imaging Lab, Department of Radiology, Guang An Men Hospital, China Academy of Chinese Medical Sciences, Beijing, China
| | - Jim Deuchars
- School of Biomedical Science, Faculty of Biological Science, University of Leeds, Leeds, United Kingdom
| | - Jozsef C. Széles
- Division for Vascular Surgery, Department of Surgery, Medical University of Vienna, Vienna, Austria
| | - Julian F. Thayer
- Department of Psychological Science, University of California, Irvine, Irvine, CA, United States
| | - Kaushik More
- Institute for Cognitive Neurology and Dementia Research, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany
- Neuromodulatory Networks, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Kristl Vonck
- Department of Neurology, Institute for Neuroscience, 4Brain, Ghent University Hospital, Gent, Belgium
| | - Laura Steenbergen
- Clinical and Cognitive Psychology and the Leiden Institute of Brain and Cognition, Leiden University, Leiden, Netherlands
| | - Lauro C. Vianna
- NeuroV̇ASQ̇ - Integrative Physiology Laboratory, Faculty of Physical Education, University of Brasilia, Brasilia, Brazil
| | - Lisa M. McTeague
- Department of Psychiatry, Medical University of South Carolina, Charleston, SC, United States
| | - Mareike Ludwig
- Department of Anatomy, Faculty of Medicine, Mersin University, Mersin, Turkey
| | - Maria G. Veldhuizen
- Mental Health and Wellbeing Research Group, Vrije Universiteit Brussel, Brussels, Belgium
| | - Marijke De Couck
- Faculty of Health Care, University College Odisee, Aalst, Belgium
- Division of Epileptology, Fondazione IRCCS Istituto Neurologico C. Besta, Milan, Italy
| | - Marina Casazza
- Department of Neurosurgery, University of Tübingen, Tübingen, Germany
| | - Marius Keute
- Institute for Neuromodulation and Neurotechnology, University Hospital and University of Tuebingen, Tuebingen, Germany
| | - Marom Bikson
- Department of Biomedical Engineering, City College of New York, New York, NY, United States
| | - Marta Andreatta
- Department of Biological Psychology, Clinical Psychology and Psychotherapy, University of Würzburg, Würzburg, Germany
- Department of Psychology, Education and Child Studies, Erasmus University Rotterdam, Rotterdam, Netherlands
| | - Martina D'Agostini
- Research Group Health Psychology, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium
| | - Mathias Weymar
- Department of Biological Psychology and Affective Science, Faculty of Human Sciences, University of Potsdam, Potsdam, Germany
- Faculty of Health Sciences Brandenburg, University of Potsdam, Potsdam, Germany
| | - Matthew Betts
- Department of Anatomy, Faculty of Medicine, Mersin University, Mersin, Turkey
- Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Magdeburg, Germany
- Center for Behavioral Brain Sciences, Otto-von-Guericke University, Magdeburg, Germany
| | - Matthias Prigge
- Neuromodulatory Networks, Leibniz Institute for Neurobiology, Magdeburg, Germany
| | - Michael Kaess
- University Hospital of Child and Adolescent Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
- Section for Translational Psychobiology in Child and Adolescent Psychiatry, Department of Child and Adolescent Psychiatry, Centre for Psychosocial Medicine, University of Heidelberg, Heidelberg, Germany
| | - Michael Roden
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
- German Center for Diabetes Research, Munich, Germany
| | - Michelle Thai
- Department of Psychology, College of Liberal Arts, University of Minnesota, Minneapolis, MN, United States
| | - Nathaniel M. Schuster
- Department of Anesthesiology, Center for Pain Medicine, University of California, San Diego Health System, La Jolla, CA, United States
| | - Nicola Montano
- Department of Internal Medicine, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Niels Hansen
- Department of Psychiatry and Psychotherapy, University of Göttingen, Göttingen, Germany
- Laboratory of Systems Neuroscience and Imaging in Psychiatry (SNIPLab), University of Göttingen, Göttingen, Germany
| | - Nils B. Kroemer
- Department of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany
| | - Peijing Rong
- Institute of Acupuncture and Moxibustion, China Academy of Chinese Medical Sciences, Beijing, China
| | - Rico Fischer
- Department of Psychology, University of Greifswald, Greifswald, Germany
| | - Robert H. Howland
- Department of Psychiatry, University of Pittsburgh School of Medicine, UPMC Western Psychiatric Hospital, Pittsburgh, PA, United States
| | - Roberta Sclocco
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States
- Department of Radiology, Logan University, Chesterfield, MO, United States
| | - Roberta Sellaro
- Cognitive Psychology Unit, Institute of Psychology, Leiden University, Leiden, Netherlands
- Leiden Institute for Brain and Cognition, Leiden, Netherlands
- Department of Developmental Psychology and Socialisation, University of Padova, Padova, Italy
| | - Ronald G. Garcia
- Athinoula A. Martinos Center for Biomedical Imaging, Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA, United States
- Department of Psychiatry, Massachusetts General Hospital, Harvard Medical School, Boston, MA, United States
| | - Sebastian Bauer
- Department of Neurology, Epilepsy Center Frankfurt Rhine-Main, Goethe-University Frankfurt, Frankfurt am Main, Germany
| | - Sofiya Gancheva
- Division of Endocrinology and Diabetology, Medical Faculty, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany
- Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University, Düsseldorf, Germany
- Heart Rhythm Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Stavros Stavrakis
- Faculty of Biological Science, School of Biomedical Science, University of Leeds, Leeds, United Kingdom
| | - Stefan Kampusch
- Institute of Electrodynamics, Microwave and Circuit Engineering, TU Wien, Vienna, Austria
- SzeleSTIM GmbH, Vienna, Austria
| | - Susan A. Deuchars
- School of Biomedical Science, Faculty of Biological Science, University of Leeds, Leeds, United Kingdom
| | - Sven Wehner
- Department of Surgery, University Hospital Bonn, Bonn, Germany
| | - Sylvain Laborde
- Department of Performance Psychology, Institute of Psychology, Deutsche Sporthochschule, Köln, Germany
| | - Taras Usichenko
- Department of Anesthesiology, University Medicine Greifswald, Greifswald, Germany
- Department of Anesthesia, McMaster University, Hamilton, ON, Canada
| | - Thomas Polak
- Laboratory of Functional Neurovascular Diagnostics, AG Early Diagnosis of Dementia, Department of Psychiatry, Psychosomatics and Psychotherapy, University Clinic Würzburg, Würzburg, Germany
| | - Tino Zaehle
- Department of Neurology, Otto-von-Guericke University, Magdeburg, Germany
| | - Uirassu Borges
- Department of Performance Psychology, Institute of Psychology, Deutsche Sporthochschule, Köln, Germany
- Department of Social and Health Psychology, Institute of Psychology, Deutsche Sporthochschule, Köln, Germany
| | - Vanessa Teckentrup
- Department of Psychiatry and Psychotherapy, University of Tübingen, Tübingen, Germany
| | - Vera K. Jandackova
- Department of Epidemiology and Public Health, Faculty of Medicine, University of Ostrava, Ostrava, Czechia
- Department of Human Movement Studies, Faculty of Education, University of Ostrava, Ostrava, Czechia
| | - Vitaly Napadow
- Department of Radiology, Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, MA, United States
- Department of Radiology, Logan University, Chesterfield, MO, United States
| | - Julian Koenig
- University Hospital of Child and Adolescent Psychiatry and Psychotherapy, University of Bern, Bern, Switzerland
- Section for Experimental Child and Adolescent Psychiatry, Department of Child and Adolescent Psychiatry, Centre for Psychosocial Medicine, University of Heidelberg, Heidelberg, Germany
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18
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Pihlaja M, Failla L, Peräkylä J, Hartikainen KM. Reduced Frontal Nogo-N2 With Uncompromised Response Inhibition During Transcutaneous Vagus Nerve Stimulation-More Efficient Cognitive Control? Front Hum Neurosci 2020; 14:561780. [PMID: 33132877 PMCID: PMC7573492 DOI: 10.3389/fnhum.2020.561780] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Accepted: 08/24/2020] [Indexed: 12/11/2022] Open
Abstract
We have previously shown invasive vagus nerve stimulation to improve attention and working memory and alter emotion-attention interaction in patients with refractory epilepsy, suggesting that VNS might be useful in the treatment of cognitive impairment. The current research focuses on whether non-invasive, transcutaneous vagus nerve stimulation (tVNS) has similar effects to VNS. Furthermore, we aimed to assess whether tVNS has an impact on cognitive control in general or on underlying brain physiology in a task that mimics everyday life demands where multiple executive functions are engaged while encountering intervening emotional stimuli. Event-related potentials (ERP) evoked in such a task, specifically centro-parietal P3 and frontal N2 were used as biomarkers for attention allocation and cognitive control required to carry out the task. A single-blinded, sham-controlled, within-subject study on healthy subjects (n = 25) was conducted using Executive Reaction Time Test (RT-test), a Go/NoGo task engaging multiple executive functions along with intervening threat-related distractors while EEG was recorded. tVNS at the left tragus and sham stimulation at the left ear lobe was alternately delivered throughout the task. To assess the impact of tVNS on neural activity underlying attention and cognitive control, centro-parietal P3 and frontal N2 peak amplitudes were measured in Go and NoGo conditions. Task performance was assessed with RTs and different error types reflecting cognitive control in general and distinct executive functions, such as working memory and response inhibition.No significant effects due to tVNS on performance in the Executive RT-test were observed. For N2 there was a main effect of stimulator status and a significant interaction of trial type (Go, NoGo) and stimulator status. Post hoc analysis revealed that tVNS resulted in a significant reduction of frontal N2 only in the NoGo condition. No significant effects were observed for P3 nor were there any effects of emotion. Diminished NoGo-N2 potential along with unaltered task performance during tVNS suggests fewer cognitive control resources were required to successfully withhold a prepotent response. Though caution is warranted, we suggest that tVNS may lead to more efficient neural processing with fewer resources needed for successful cognitive control, providing promise for its potential use in cognitive enhancement.
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Affiliation(s)
- Mia Pihlaja
- Behavioral Neurology Research Unit, Tampere University Hospital, Tampere, Finland.,Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Laura Failla
- Behavioral Neurology Research Unit, Tampere University Hospital, Tampere, Finland.,Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
| | - Jari Peräkylä
- Behavioral Neurology Research Unit, Tampere University Hospital, Tampere, Finland.,Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
| | - Kaisa M Hartikainen
- Behavioral Neurology Research Unit, Tampere University Hospital, Tampere, Finland.,Faculty of Medicine and Health Technology, Tampere University, Tampere, Finland
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19
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Possible links between gut-microbiota and attention-deficit/hyperactivity disorders in children and adolescents. Eur J Nutr 2020; 59:3391-3403. [PMID: 32918136 DOI: 10.1007/s00394-020-02383-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2020] [Accepted: 09/03/2020] [Indexed: 12/14/2022]
Abstract
An association between gut-microbiota and several neuropsychiatric conditions including autism, depression, anxiety, schizophrenia, and attention-deficit/hyperactivity disorder (ADHD) has been observed. Despite being the most prevalent neurodevelopmental disorders in children and adolescents worldwide, the etiology and curative approaches to treatment of ADHD remain unclear. There is a probability that gut-microbiota may contribute to ADHD via bidirectional communication between the gut and brain, a system known as the "gut-brain axis". Although a mechanistic link in the gut-brain axis in ADHD has been proposed, there is still a lack of information about the correlation of the microbiome profile with the mechanisms involved. The objective of this review was to summarize the diversity of the gut-microbiota and taxonomic profiles in children and adolescents with ADHD. In this review, we have provided an overview of the association between ADHD and gut-microbiota. The evidence pertinent to potentially distinctive gut-microbiota in children and adolescents with ADHD is also discussed and compared to that of their non-ADHD peers. Finally, the implications and future directions for investigation into the gut microbiome in ADHD patients are proposed.
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20
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Marras CE, Colicchio G, De Palma L, De Benedictis A, Di Gennaro G, Cavaliere M, Cesaroni E, Consales A, Asioli S, Caulo M, Villani F, Zamponi N. Health Technology Assessment Report on Vagus Nerve Stimulation in Drug-Resistant Epilepsy. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:E6150. [PMID: 32847092 PMCID: PMC7504285 DOI: 10.3390/ijerph17176150] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/05/2020] [Revised: 07/31/2020] [Accepted: 08/13/2020] [Indexed: 01/12/2023]
Abstract
Background: Vagus nerve stimulation (VNS) is a palliative treatment for medical intractable epileptic syndromes not eligible for resective surgery. Health technology assessment (HTA) represents a modern approach to the analysis of technologies used for healthcare. The purpose of this study is to assess the clinical, organizational, financial, and economic impact of VNS therapy in drug-resistant epilepsies and to establish the congruity between costs incurred and health service reimbursement. Methods: The present study used an HTA approach. It is based on an extensive detailed bibliographic search on databases (Medline, Pubmed, Embase and Cochrane, sites of scientific societies and institutional sites). The HTA study includes the following issues: (a) social impact and costs of the disease; (b) VNS eligibility and clinical results; (c) quality of life (QoL) after VNS therapy; (d) economic impact and productivity regained after VNS; and (e) costs of VNS. Results: Literature data indicate VNS as an effective treatment with a potential positive impact on social aspects and on quality of life. The diagnosis-related group (DRG) financing, both on national and regional levels, does not cover the cost of the medical device. There was an evident insufficient coverage of the DRG compared to the full cost of implanting the device. Conclusions: VNS is a palliative treatment for reducing seizure frequency and intensity. Despite its economic cost, VNS should improve patients' quality of life and reduce care needs.
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Affiliation(s)
- Carlo Efisio Marras
- Neurosurgery Unit, Department of Neuroscience, IRCCS Bambino Gesù Children Hospital, 00165 Rome, Italy; (A.D.B.); (M.C.)
| | - Gabriella Colicchio
- Department of Neurosurgery, UCSC Gemelli University Hospital, 00167 Rome, Italy;
| | - Luca De Palma
- Pediatric Neurology Unit, Department of Neuroscience, IRCCS Bambino Gesù Children Hospital, 00165 Rome, Italy;
| | - Alessandro De Benedictis
- Neurosurgery Unit, Department of Neuroscience, IRCCS Bambino Gesù Children Hospital, 00165 Rome, Italy; (A.D.B.); (M.C.)
| | | | - Marilou Cavaliere
- Neurosurgery Unit, Department of Neuroscience, IRCCS Bambino Gesù Children Hospital, 00165 Rome, Italy; (A.D.B.); (M.C.)
- Institute of Neurosurgery, University of Milan Bicocca, 20900 Milan, Italy
| | - Elisabetta Cesaroni
- Pediatric Neurology Unit, Salesi Children Hospital, 60123 Ancona, Italy; (E.C.); (N.Z.)
| | | | - Sofia Asioli
- Department of Biomedical and Neuromotor Sciences, Section of Anatomic Pathology, Bellaria Hospital, University of Bologna, 40139 Bologna, Italy;
| | - Massimo Caulo
- Department of Neuroscience, Imaging and Clinical Sciences, University of Chieti, 66100 Chieti, Italy;
| | - Flavio Villani
- Division of Clinical Neurophysiology and Epilepsy Center, IRCCS, San Martino Hospital, 16132 Genoa, Italy;
| | - Nelia Zamponi
- Pediatric Neurology Unit, Salesi Children Hospital, 60123 Ancona, Italy; (E.C.); (N.Z.)
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21
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Meier M, Unternaehrer E, Schorpp SM, Wenzel M, Benz A, Bentele UU, Dimitroff SJ, Denk B, Prüssner JC. The Opposite of Stress. Exp Psychol 2020; 67:150-159. [PMID: 32729407 DOI: 10.1027/1618-3169/a000483] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Cognition is affected by psychophysiological states. While the influence of stress on cognition has been investigated intensively, less studies have addressed how the opposite of stress, a state of relaxation, affects cognition. We investigated whether the extent of parasympathetic activation is positively related to divergent thinking. Sixty healthy female participants were randomly allocated to a standardized vagus nerve massage (n = 19), a standardized soft shoulder massage (n = 22), or a resting control group (n = 19). Subsequently, participants completed the Alternative Uses Test (AUT), a measure of divergent thinking. Respiratory sinus arrhythmia (RSA), a vagally mediated heart rate variability component, was monitored throughout the experiment. The area under the curve with respect to the increase was calculated for RSA trajectories as an indicator of vagal tone during the relaxing intervention. Regressions tested the effect of vagal tone on AUT outcomes. We found an association between vagal tone and subsequent AUT outcomes. Yet, this association was no longer significant when controlling for the effect of the creative potential of an individual, which was strongly related to AUT outcomes. Being exploratory, we found a positive association between creative potential and vagal tone. These results imply that creative potential might be related to the capacity to relax.
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Affiliation(s)
- Maria Meier
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany
| | - Eva Unternaehrer
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany.,Department of Child and Adolescent Psychiatry, University of Basel, Psychiatric University Hospital, Basel, Switzerland
| | - Sabine M Schorpp
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany
| | - Maya Wenzel
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany
| | - Annika Benz
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany
| | - Ulrike U Bentele
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany
| | - Stephanie J Dimitroff
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany
| | - Bernadette Denk
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany
| | - Jens C Prüssner
- Department of Psychology, Division of Clinical Neuropsychology, University of Konstanz, Konstanz, Germany
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22
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Burger A, Van der Does W, Brosschot J, Verkuil B. From ear to eye? No effect of transcutaneous vagus nerve stimulation on human pupil dilation: A report of three studies. Biol Psychol 2020; 152:107863. [DOI: 10.1016/j.biopsycho.2020.107863] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Revised: 12/09/2019] [Accepted: 02/03/2020] [Indexed: 12/11/2022]
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23
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Colzato L, Beste C. A literature review on the neurophysiological underpinnings and cognitive effects of transcutaneous vagus nerve stimulation: challenges and future directions. J Neurophysiol 2020; 123:1739-1755. [PMID: 32208895 DOI: 10.1152/jn.00057.2020] [Citation(s) in RCA: 50] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Brain stimulation approaches are important to gain causal mechanistic insights into the relevance of functional brain regions and/or neurophysiological systems for human cognitive functions. In recent years, transcutaneous vagus nerve stimulation (tVNS) has attracted considerable popularity. It is a noninvasive brain stimulation technique based on the stimulation of the vagus nerve. The stimulation of this nerve activates subcortical nuclei, such as the locus coeruleus and the nucleus of the solitary tract, and from there, the activation propagates to the cortex. Since tVNS is a novel stimulation technique, this literature review outlines a brief historical background of tVNS, before detailing underlying neurophysiological mechanisms of action, stimulation parameters, cognitive effects of tVNS on healthy humans, and, lastly, current challenges and future directions of tVNS research in cognitive functions. Although more research is needed, we conclude that tVNS, by increasing norepineprine (NE) and gamma-aminobutyric acid (GABA) levels, affects NE- and GABA-related cognitive performance. The review provides detailed background information how to use tVNS as a neuromodulatory tool in cognitive neuroscience and outlines important future leads of research on tVNS.
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Affiliation(s)
- Lorenza Colzato
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Dresden, Germany.,Department of Cognitive Psychology, Institute of Cognitive Neuroscience, Faculty of Psychology, Ruhr University Bochum, Bochum, Germany.,Cognitive Psychology, Faculty of Psychology, Shandong Normal University, Jinan, China
| | - Christian Beste
- Cognitive Neurophysiology, Department of Child and Adolescent Psychiatry, Faculty of Medicine, TU Dresden, Dresden, Germany.,Cognitive Psychology, Faculty of Psychology, Shandong Normal University, Jinan, China
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24
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Burger AM, D'Agostini M, Verkuil B, Van Diest I. Moving beyond belief: A narrative review of potential biomarkers for transcutaneous vagus nerve stimulation. Psychophysiology 2020; 57:e13571. [PMID: 32202671 DOI: 10.1111/psyp.13571] [Citation(s) in RCA: 67] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 01/15/2020] [Accepted: 02/01/2020] [Indexed: 12/25/2022]
Abstract
Transcutaneous vagus nerve stimulation (tVNS) is a non-invasive neurostimulation technique that is currently being tested as a potential treatment for a myriad of neurological and psychiatric disorders. However, the working mechanisms underlying tVNS are poorly understood and it remains unclear whether stimulation activates the vagus nerve for every participant. Finding a biological marker of tVNS is imperative, as it can help guide research on clinical applications and can inform researchers on optimal stimulation sites and parameters to further optimize treatment efficacy. In this narrative review, we discuss five potential biomarkers for tVNS and review currently available evidence for these markers for both invasive and tVNS. While some of these biomarkers hold promise from a theoretical perspective, none of the potential biomarkers provide clear and definitive indications that tVNS increases the vagal activity or augments activity in the locus coeruleus-noradrenaline network. We conclude the review by providing several recommendations for how to tackle the challenges and opportunities when researching potential biomarkers for the effects of tVNS.
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Affiliation(s)
- Andreas Michael Burger
- Health Psychology Research Group, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium.,Biological Psychology Research Group, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium
| | - Martina D'Agostini
- Health Psychology Research Group, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium
| | - Bart Verkuil
- Department of Clinical Psychology, Leiden University, Leiden, the Netherlands
| | - Ilse Van Diest
- Health Psychology Research Group, Faculty of Psychology and Educational Sciences, University of Leuven, Leuven, Belgium
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25
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Keute M, Demirezen M, Graf A, Mueller NG, Zaehle T. No modulation of pupil size and event-related pupil response by transcutaneous auricular vagus nerve stimulation (taVNS). Sci Rep 2019; 9:11452. [PMID: 31391505 PMCID: PMC6685960 DOI: 10.1038/s41598-019-47961-4] [Citation(s) in RCA: 49] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Accepted: 07/24/2019] [Indexed: 01/20/2023] Open
Abstract
Transcutaneous auricular vagus nerve stimulation (taVNS) bears therapeutic potential for a wide range of medical conditions. However, previous studies have found substantial interindividual variability in responsiveness to taVNS, and no reliable predictive biomarker for stimulation success has been developed so far. In this study, we investigate pupil size and event-related pupil response as candidate biomarkers. Both measures have a direct physiological link to the activity of the locus coeruleus (LC), a brainstem structure and the main source of norepinephrine in the brain. LC activation is considered one of the key mechanisms of action of taVNS, therefore, we expected a clear increase of the pupillary measures under taVNS compared to sham (placebo) stimulation, such that it could serve as a prospective predictor for individual clinical and physiological taVNS effects in future studies. We studied resting pupil size and pupillary responses to target stimuli in an auditory oddball task in 33 healthy young volunteers. We observed stronger pupil responses to target than to standard stimuli. However, and contrary to our hypothesis, neither pupil size nor the event-related pupil response nor behavioral performance were modulated by taVNS. We discuss potential explanations for this negative finding and its implications for future clinical investigation and development of taVNS.
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Affiliation(s)
- Marius Keute
- Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Mustafa Demirezen
- Department of Neurology, Otto von Guericke University, Magdeburg, Germany
| | - Alina Graf
- Neuroprotection Group, German Center for Neurodegenerative Diseases, Magdeburg, Germany
| | - Notger G Mueller
- Department of Neurology, Otto von Guericke University, Magdeburg, Germany.,Neuroprotection Group, German Center for Neurodegenerative Diseases, Magdeburg, Germany.,Center for Behavioral Brain Sciences, Magdeburg, Germany
| | - Tino Zaehle
- Department of Neurology, Otto von Guericke University, Magdeburg, Germany. .,Center for Behavioral Brain Sciences, Magdeburg, Germany.
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26
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Transcutaneous vagus nerve stimulation (tVNS) enhances conflict-triggered adjustment of cognitive control. COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2019; 18:680-693. [PMID: 29693214 DOI: 10.3758/s13415-018-0596-2] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Response conflicts play a prominent role in the flexible adaptation of behavior as they represent context-signals that indicate the necessity for the recruitment of cognitive control. Previous studies have highlighted the functional roles of the affectively aversive and arousing quality of the conflict signal in triggering the adaptation process. To further test this potential link with arousal, participants performed a response conflict task in two separate sessions with either transcutaneous vagus nerve stimulation (tVNS), which is assumed to activate the locus coeruleus-noradrenaline (LC-NE) system, or with neutral sham stimulation. In both sessions the N2 and P3 event-related potentials (ERP) were assessed. In line with previous findings, conflict interference, the N2 and P3 amplitude were reduced after conflict. Most importantly, this adaptation to conflict was enhanced under tVNS compared to sham stimulation for conflict interference and the N2 amplitude. No effect of tVNS on the P3 component was found. These findings suggest that tVNS increases behavioral and electrophysiological markers of adaptation to conflict. Results are discussed in the context of the potentially underlying LC-NE and other neuromodulatory (e.g., GABA) systems. The present findings add important pieces to the understanding of the neurophysiological mechanisms of conflict-triggered adjustment of cognitive control.
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27
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Noble LJ, Souza RR, McIntyre CK. Vagus nerve stimulation as a tool for enhancing extinction in exposure-based therapies. Psychopharmacology (Berl) 2019; 236:355-367. [PMID: 30091004 PMCID: PMC6368475 DOI: 10.1007/s00213-018-4994-5] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/23/2018] [Accepted: 08/01/2018] [Indexed: 02/04/2023]
Abstract
RATIONALE Emotionally traumatic experiences can lead to maladaptive memories that are enduring and intrusive. The goal of exposure-based therapies is to extinguish conditioned fears through repeated, unreinforced exposures to reminders of traumatic events. The extinction of conditioned fear depends upon the consolidation of new memories made during exposure to reminders. An impairment in extinction recall, observed in certain patient populations, can interfere with progress in exposure-based therapies, and the drive to avoid thoughts and reminders of the trauma can undermine compliance and increase dropout rate. Effective adjuncts to exposure-based therapies should improve the consolidation and maintenance of the extinction memory or improve the tolerability of the therapy. Under stressful conditions, the vagus nerve responds to elevations in epinephrine and signals the brain to facilitate the storage of new memories while, as part of the parasympathetic nervous system, it slows the sympathetic response. OBJECTIVE Here, we review studies relevant to fear extinction, describing the anatomical and functional characteristics of the vagus nerve and mechanisms of vagus nerve stimulation (VNS)-induced memory enhancement and plasticity. RESULTS We propose that stimulation of the left cervical vagus nerve during exposure to conditioned cues signals the brain to store new memories just as epinephrine or emotional arousal would do, but bypasses the peripheral sympathetic "fight-or-flight" response. CONCLUSIONS In support of this hypothesis, we have found that VNS accelerates extinction and prevents reinstatement of conditioned fear in rats. Finally, we propose future studies targeting the optimization of stimulation parameters and the search for biomarkers of VNS effectiveness that may improve exposure therapy outcomes.
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Affiliation(s)
- Lindsey J Noble
- School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA
| | - Rimenez R Souza
- School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA
| | - Christa K McIntyre
- School of Behavioral Brain Sciences, The University of Texas at Dallas, 800 West Campbell Road, Richardson, TX, 75080, USA.
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28
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Warren CM, Tona KD, Ouwerkerk L, van Paridon J, Poletiek F, van Steenbergen H, Bosch JA, Nieuwenhuis S. The neuromodulatory and hormonal effects of transcutaneous vagus nerve stimulation as evidenced by salivary alpha amylase, salivary cortisol, pupil diameter, and the P3 event-related potential. Brain Stimul 2018; 12:635-642. [PMID: 30591360 DOI: 10.1016/j.brs.2018.12.224] [Citation(s) in RCA: 86] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2018] [Revised: 12/07/2018] [Accepted: 12/12/2018] [Indexed: 12/12/2022] Open
Abstract
BACKGROUND Transcutaneous vagus nerve stimulation (tVNS) is a new, non-invasive technique being investigated as an intervention for a variety of clinical disorders, including epilepsy and depression. It is thought to exert its therapeutic effect by increasing central norepinephrine (NE) activity, but the evidence supporting this notion is limited. OBJECTIVE In order to test for an impact of tVNS on psychophysiological and hormonal indices of noradrenergic function, we applied tVNS in concert with assessment of salivary alpha amylase (SAA) and cortisol, pupil size, and electroencephalograph (EEG) recordings. METHODS Across three experiments, we applied real and sham tVNS to 61 healthy participants while they performed a set of simple stimulus-discrimination tasks. Before and after the task, as well as during one break, participants provided saliva samples and had their pupil size recorded. EEG was recorded throughout the task. The target for tVNS was the cymba conchae, which is heavily innervated by the auricular branch of the vagus nerve. Sham stimulation was applied to the ear lobe. RESULTS P3 amplitude was not affected by tVNS (Experiment 1A: N = 24; Experiment 1B: N = 20; Bayes factor supporting null model = 4.53), nor was pupil size (Experiment 2: N = 16; interaction of treatment and time: p = .79). However, tVNS increased SAA (Experiments 1A and 2: N = 25) and attenuated the decline of salivary cortisol compared to sham (Experiment 2: N = 17), as indicated by significant interactions involving treatment and time (p = .023 and p = .040, respectively). CONCLUSION These findings suggest that tVNS modulates hormonal indices but not psychophysiological indices of noradrenergic function.
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Affiliation(s)
- C M Warren
- Institute of Psychology, Leiden University, Leiden, 2333, AK, Netherlands; Leiden Institute for Brain and Cognition, Leiden University, Leiden, 2300, RC, Netherlands.
| | - K D Tona
- Institute of Psychology, Leiden University, Leiden, 2333, AK, Netherlands; Leiden Institute for Brain and Cognition, Leiden University, Leiden, 2300, RC, Netherlands
| | - L Ouwerkerk
- Institute of Psychology, Leiden University, Leiden, 2333, AK, Netherlands
| | - J van Paridon
- Institute of Psychology, Leiden University, Leiden, 2333, AK, Netherlands; Max Planck Institute of Psycholinguistics, Nijmegen, 6525, XD, Netherlands
| | - F Poletiek
- Institute of Psychology, Leiden University, Leiden, 2333, AK, Netherlands; Max Planck Institute of Psycholinguistics, Nijmegen, 6525, XD, Netherlands
| | - Henk van Steenbergen
- Institute of Psychology, Leiden University, Leiden, 2333, AK, Netherlands; Leiden Institute for Brain and Cognition, Leiden University, Leiden, 2300, RC, Netherlands
| | - J A Bosch
- Department of Clinical Psychology, University of Amsterdam, Amsterdam, 1018, XA, Netherlands; Mannheim Institute of Public Health, Heidelberg University, Mannheim, 68167, Germany
| | - S Nieuwenhuis
- Institute of Psychology, Leiden University, Leiden, 2333, AK, Netherlands; Leiden Institute for Brain and Cognition, Leiden University, Leiden, 2300, RC, Netherlands
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29
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Neurocognitive effects of umami: association with eating behavior and food choice. Neuropsychopharmacology 2018; 43:2009-2016. [PMID: 29599485 PMCID: PMC6098010 DOI: 10.1038/s41386-018-0044-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/24/2017] [Revised: 02/25/2018] [Accepted: 03/01/2018] [Indexed: 12/14/2022]
Abstract
Free glutamate, a key substance underlying the umami taste of foods, fulfills a number of physiological functions related to energy balance. Previous experimental studies have shown that intake of a broth or soup supplemented with monosodium glutamate (MSG) prior to a meal can decrease appetite and food intake, particularly in women with propensity to overeat and gain weight. In this study, we examined potential neurocognitive mechanisms underlying this effect. We evaluated changes after intake of a chicken broth with or without MSG added (MSG+/MSG-) in a sample of healthy young women. Subjects were assessed with a food-modified computerized inhibitory control task, a buffet meal test with eye-tracking, and brain responses during a food choice paradigm evaluated with functional neuroimaging. We found evidence for improvement in key parameters related to inhibitory control following intake of the MSG+ broth, particularly in subjects with high levels of eating disinhibition, who also showed lower intake of saturated fat during the meal. Additionally, consumption of the MSG+ broth led to a reduction of the rate of fixation switches between plates at the meal, and increased engagement of a brain region in the left dorsolateral prefrontal cortex previously associated with successful self-control during dietary decisions. Altogether, these results, while preliminary, suggest potential facilitating effects of glutamate (MSG) on cognitive executive processes that are relevant for the support of healthy eating behaviors and food choice.
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Saoji AA, Raghavendra BR, Rajesh SK, Manjunath NK. Immediate Effects of Yoga Breathing with Intermittent Breath Holding on Response Inhibition among Healthy Volunteers. Int J Yoga 2018; 11:99-104. [PMID: 29755217 PMCID: PMC5934957 DOI: 10.4103/ijoy.ijoy_65_16] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Background: There is very little evidence available on the effects of yoga-based breathing practices on response inhibition. The current study used stop-signal paradigm to assess the effects of yoga breathing with intermittent breath holding (YBH) on response inhibition among healthy volunteers. Materials and Methods: Thirty-six healthy volunteers (17 males + 19 females), with mean age of 20.31 ± 3.48 years from a university, were recruited in a within-subject repeated measures (RM) design. The recordings for stop signal task were performed on three different days for baseline, post-YBH, and post yogic breath awareness (YBA) sessions. Stop-signal reaction time (SSRT), mean reaction time to go stimuli (go RT), and the probability of responding on-stop signal trials (p [r/s]) were analyzed for 36 volunteers using RM analysis of variance. Results: SSRT reduced significantly in both YBH (218.33 ± 38.38) and YBA (213.15 ± 37.29) groups when compared to baseline (231.98 ± 29.54). No significant changes were observed in go RT and p (r/s). Further, the changes in SSRT were not significantly different among YBH and YBA groups. Conclusion: Both YBH and YBA groups were found to enhance response inhibition in the stop-signal paradigm. YBH could be further evaluated in clinical settings for conditions where response inhibition is altered.
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Affiliation(s)
- Apar Avinash Saoji
- Division of Yoga and Life Sciences, Swami Vivekananda Yoga Anusandhana Samthana, Bengaluru, Karnataka, India
| | - B R Raghavendra
- Division of Yoga and Life Sciences, Swami Vivekananda Yoga Anusandhana Samthana, Bengaluru, Karnataka, India
| | - S K Rajesh
- Division of Yoga and Life Sciences, Swami Vivekananda Yoga Anusandhana Samthana, Bengaluru, Karnataka, India
| | - N K Manjunath
- Division of Yoga and Life Sciences, Swami Vivekananda Yoga Anusandhana Samthana, Bengaluru, Karnataka, India
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van Bochove ME, De Taeye L, Raedt R, Vonck K, Meurs A, Boon P, Dauwe I, Notebaert W, Verguts T. Reduced distractor interference during vagus nerve stimulation. Int J Psychophysiol 2018; 128:93-99. [PMID: 29574234 DOI: 10.1016/j.ijpsycho.2018.03.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2017] [Revised: 03/15/2018] [Accepted: 03/20/2018] [Indexed: 12/19/2022]
Abstract
Suppressing irrelevant information in decision making is an essential everyday skill. We studied whether this ability could be improved in epileptic patients during vagus nerve stimulation (VNS). VNS is known to increase norepinephrine (NE) in the brain. NE is thought to improve several aspects of cognitive control, including the suppression of irrelevant information. Nineteen epileptic VNS patients executed the Eriksen flanker task twice, both during on and off stimulation. Distractor interference was indexed by the congruency effect, a standard empirical marker of cognitive control. We found a reduced congruency effect during stimulation, which indicates an improved ability to suppress distractor interference. This effect was only found in patients that are clinically determined VNS-responders (n = 10). As VNS increases NE in VNS-responders, our finding suggests a beneficial role of NE in cognitive control. At the same time, it suggests that VNS does not only reduce seizure frequency in epileptic patients, but also improves cognitive control.
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Affiliation(s)
- Marlies E van Bochove
- Department of Experimental Psychology, Ghent University, Belgium; Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands.
| | - Leen De Taeye
- Laboratory for Clinical and Experimental Neurophysiology, Department of Neurology, Institute for Neuroscience, Ghent University Hospital, Belgium
| | - Robrecht Raedt
- Laboratory for Clinical and Experimental Neurophysiology, Department of Neurology, Institute for Neuroscience, Ghent University Hospital, Belgium
| | - Kristl Vonck
- Laboratory for Clinical and Experimental Neurophysiology, Department of Neurology, Institute for Neuroscience, Ghent University Hospital, Belgium
| | - Alfred Meurs
- Laboratory for Clinical and Experimental Neurophysiology, Department of Neurology, Institute for Neuroscience, Ghent University Hospital, Belgium
| | - Paul Boon
- Laboratory for Clinical and Experimental Neurophysiology, Department of Neurology, Institute for Neuroscience, Ghent University Hospital, Belgium
| | - Ine Dauwe
- Laboratory for Clinical and Experimental Neurophysiology, Department of Neurology, Institute for Neuroscience, Ghent University Hospital, Belgium
| | - Wim Notebaert
- Department of Experimental Psychology, Ghent University, Belgium
| | - Tom Verguts
- Department of Experimental Psychology, Ghent University, Belgium.
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