Effects of Anodal Transcranial Direct Current Stimulation and Serotonergic Enhancement on Memory Performance

Einleitung: Lernen und Gedächtnis sind wesentliche Voraussetzungen für ein selbstständiges Leben. Die Fähigkeit neue Informationen und Fertigkeiten zu erlernen, verarbeiten und wieder abzurufen ist individuell sehr unterschiedlich, unterliegt im Laufe des Alterns einem gewissen physiologischen Abbau und kann durch verschiedenste Faktoren und Maßnahmen beeinflusst werden. Die anodale transkranielle Gleichstromstimulation (atDCS) als nicht-invasive und gut verträgliche Methode hat sich bereits als vielversprechender Ansatz der Lern- und Gedächtnismodulation hervorgetan. Bisher ist deren Effekt jedoch eher gering und von kurzer Dauer. Der Botenstoff Serotonin spielt eine wichtige Rolle bei Lern- und Gedächtnisprozessen des Menschen. In vorausgehenden Studien konnte ein Einfluss des Serotonins auf die durch tDCS generierte Neuroplastizität gezeigt werden. Ob Serotonin die Effekte der atDCS auf die Lern-und Gedächtnisleistung ebenfalls positiv beeinflussen kann, ist jedoch noch unklar. Methoden: In einer doppelt-verblindeten, randomisierten, Placebo-kontrollierten Studie im Cross-over-Design untersuchten wir den Effekt der Kombination von atDCS mit dem SSRI Citalopram (1 x 20mg) auf die Lern-und Gedächtnisleistung bei insgesamt 40 gesunden jungen und älteren Probanden. Objektiviert wurde dies anhand der computerbasierten visuell-räumlichen Gedächtnisaufgabe ‚LOCATO’. Die Stimulation per atDCS (20 Minuten, 1mA) erfolgte über dem rechten temporo-parietalen Cortex. Jeder Proband durchlief vier Versuchsbedingungen (SSRI+atDCS, SSRI+Sham, Placebo+atDCS und Placebo+Sham). Getestet wurde die Gedächtnisleistung in einem direkten Abruf nach dem Training sowie in drei späteren Abrufen. Ergebnisse: Die Probanden schnitten im direkten Abruf in der Kombinationsbedingung SSRI+atDCS signifikant besser ab als in den Vergleichsbedingungen Placebo+atDCS sowie Placebo+Sham. Auch für die Medikation allgemein (SSRI vs. Placebo) konnte ein signifikanter positiver Einfluss auf die Gedächtnisleistung gezeigt werden. Bis auf einen Trend zeigte sich jedoch kein länger anhaltender Effekt in den späteren Abrufen. Auch für atDCS alleine konnte kein signifikanter positiver Einfluss nachgewiesen werden. Diskussion: Zwar konnte die tatsächliche Gedächtnisleistung bei gesunden jungen und älteren Probanden nur leicht gesteigert werden, jedoch ließ sich der signifikant positive Effekt bereits durch eine einmalige Anwendung der Kombination von atDCS mit dem SSRI Citalopram erreichen. Weiterführende größere Studien sind nun notwendig um diesen vielversprechenden Ansatz der Lern- und Gedächtnisverbesserung eingehend zu untersuchen. Es sollte getestet werden, ob sich der Effekt durch eine längere SSRI-Gabe und serielle Stimulation ausbauen lässt. Ebenso sollte die Methode bei Probanden mit bereits bestehenden Gedächtniseinschränkungen wie beispielsweise einem MCI (mild cognitive impairment) untersucht werden.Introduction: Learning and memory are key prerequisites for a self-reliant life. The ability to learn, process and recall new information and skills differs from person to person, and there is a certain physiological decline of those capacities throughout time. Furthermore, this ability can be influenced by various factors and procedures. For example, the anodal transcranial direct current simulation (atDCS) as a non-invasive and easy to apply method seems to be a promising approach for memory and learning enhancement. Until now effectiveness and duration of tDCS are rather limited though. In addition, the second messenger serotonin has an important effect on learning and memory in humans. Previous studies have also shown a relevant influence of serotonin on the atDCS-induced neuroplasticity. Whether it is also able to enhance the effects of atDCS on learning and memory is yet to be determined. Methods: We studied the effects of the combination of atDCS and the SSRI Citalopram on learning and memory performance in a double-blinded randomised placebo controlled trial. 40 young and older healthy adults participated in this study. The outcome was measured using the computer based object location learning task LOCATO. A 20-minute stimulation over the right temporoparietal cortex (1 mA) was applied. Using a cross-over design, each participant went through a series of four test conditions (SSRI+atDCS, SSRI+Sham, Placebo+atDCS and Placebo+Sham). The memory performance was measured by an immediate recall, representing our primary outcome, as well as three delayed cued recalls. Results: In the test condition SSRI+atDCS participants achieved significantly higher immediate recall scores (primary outcome) compared to Placebo+atDCS, as well as Placebo+Sham. We also found a significant effect on the memory performance of medication in general (SSRI vs. Placebo). Except for one trend, however, no persistent effect on the memory performance could be shown in the delayed recalls. The same holds for the application of atDCS alone. Discussion: Even though the absolute effect on the memory enhancement was small, we were able to show a significant improvement by a one-time application of atDCS and the SSRI Citalopram. Further studies are needed to investigate the great potential of serotonergic enhancement on the atDCS-induced memory improvement. One possible direction would be to examine the effect of longitudinal stimulation or repeated SSRI application. Furthermore, the intervention should be tested in participants already suffering from a mild cognitive impairment or dementia.

Neurological update: use of cardiac troponin in patients with stroke

Cardiac troponin is a specific and sensitive biomarker to identify and quantify myocardial injury. Myocardial injury is frequently detected after acute ischemic stroke and strongly associated with unfavorable outcomes. Concomitant acute coronary syndrome is only one of several possible differential diagnoses that may cause elevation of cardiac troponin after stroke. As a result, there are uncertainties regarding the correct interpretation and optimal management of stroke patients with myocardial injury in clinical practice. Elevation of cardiac troponin may occur as part of a ‘Stroke-Heart Syndrome’. The term ‘Stroke-Heart Syndrome’ subsumes a clinical spectrum of cardiac complications after stroke including cardiac injury, dysfunction, and arrhythmia which may relate to disturbances of autonomic function and the brain–heart axis. In this review, we provide an up-to-date overview about prognostic implications, mechanisms, and management of elevated cardiac troponin levels in patients with acute ischemic stroke

Clinical correlates and prognostic impact of neurologic disorders in Takotsubo syndrome

Cardiac alterations are frequently observed after acute neurological disorders. Takotsubo syndrome (TTS) represents an acute heart failure syndrome and is increasingly recognized as part of the spectrum of cardiac complications observed after neurological disorders. A systematic investigation of TTS patients with neurological disorders has not been conducted yet. The aim of the study was to expand insights regarding neurological disease entities triggering TTS and to investigate the clinical profile and outcomes of TTS patients after primary neurological disorders. The International Takotsubo Registry is an observational multicenter collaborative effort of 45 centers in 14 countries (ClinicalTrials.gov, identifier NCT01947621). All patients in the registry fulfilled International Takotsubo Diagnostic Criteria. For the present study, patients were included if complete information on acute neurological disorders were available. 2402 patients in whom complete information on acute neurological status were available were analyzed. In 161 patients (6.7%) an acute neurological disorder was identified as the preceding triggering factor. The most common neurological disorders were seizures, intracranial hemorrhage, and ischemic stroke. Time from neurological symptoms to TTS diagnosis was <= 2 days in 87.3% of cases. TTS patients with neurological disorders were younger, had a lower female predominance, fewer cardiac symptoms, lower left ventricular ejection fraction, and higher levels of cardiac biomarkers. TTS patients with neurological disorders had a 3.2-fold increased odds of in-hospital mortality compared to TTS patients without neurological disorders. In this large-scale study, 1 out of 15 TTS patients had an acute neurological condition as the underlying triggering factor. Our data emphasize that a wide spectrum of neurological diseases ranging from benign to life-threatening encompass TTS. The high rates of adverse events highlight the need for clinical awareness

Clinical correlates and prognostic impact of neurologic disorders in Takotsubo syndrome

© The Author(s) 2021. Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.Cardiac alterations are frequently observed after acute neurological disorders. Takotsubo syndrome (TTS) represents an acute heart failure syndrome and is increasingly recognized as part of the spectrum of cardiac complications observed after neurological disorders. A systematic investigation of TTS patients with neurological disorders has not been conducted yet. The aim of the study was to expand insights regarding neurological disease entities triggering TTS and to investigate the clinical profile and outcomes of TTS patients after primary neurological disorders. The International Takotsubo Registry is an observational multicenter collaborative effort of 45 centers in 14 countries (ClinicalTrials.gov, identifier NCT01947621). All patients in the registry fulfilled International Takotsubo Diagnostic Criteria. For the present study, patients were included if complete information on acute neurological disorders were available. 2402 patients in whom complete information on acute neurological status were available were analyzed. In 161 patients (6.7%) an acute neurological disorder was identified as the preceding triggering factor. The most common neurological disorders were seizures, intracranial hemorrhage, and ischemic stroke. Time from neurological symptoms to TTS diagnosis was ≤ 2 days in 87.3% of cases. TTS patients with neurological disorders were younger, had a lower female predominance, fewer cardiac symptoms, lower left ventricular ejection fraction, and higher levels of cardiac biomarkers. TTS patients with neurological disorders had a 3.2-fold increased odds of in-hospital mortality compared to TTS patients without neurological disorders. In this large-scale study, 1 out of 15 TTS patients had an acute neurological condition as the underlying triggering factor. Our data emphasize that a wide spectrum of neurological diseases ranging from benign to life-threatening encompass TTS. The high rates of adverse events highlight the need for clinical awareness.The International Takotsubo Registry was supported by the Biss Davies Charitable Trust. Dr. Scheitz has been supported by the Corona Foundation. Dr. Templin has been supported by the H.H. Sheikh Khalifa bin Hamad Al-Thani Research Programme and the Swiss Heart Foundation.info:eu-repo/semantics/publishedVersio

Clinical correlates and prognostic impact of neurologic disorders in Takotsubo syndrome

Cardiac alterations are frequently observed after acute neurological disorders. Takotsubo syndrome (TTS) represents an acute heart failure syndrome and is increasingly recognized as part of the spectrum of cardiac complications observed after neurological disorders. A systematic investigation of TTS patients with neurological disorders has not been conducted yet. The aim of the study was to expand insights regarding neurological disease entities triggering TTS and to investigate the clinical profile and outcomes of TTS patients after primary neurological disorders. The International Takotsubo Registry is an observational multicenter collaborative effort of 45 centers in 14 countries (ClinicalTrials.gov, identifier NCT01947621). All patients in the registry fulfilled International Takotsubo Diagnostic Criteria. For the present study, patients were included if complete information on acute neurological disorders were available. 2402 patients in whom complete information on acute neurological status were available were analyzed. In 161 patients (6.7%) an acute neurological disorder was identified as the preceding triggering factor. The most common neurological disorders were seizures, intracranial hemorrhage, and ischemic stroke. Time from neurological symptoms to TTS diagnosis was ≤ 2 days in 87.3% of cases. TTS patients with neurological disorders were younger, had a lower female predominance, fewer cardiac symptoms, lower left ventricular ejection fraction, and higher levels of cardiac biomarkers. TTS patients with neurological disorders had a 3.2-fold increased odds of in-hospital mortality compared to TTS patients without neurological disorders. In this large-scale study, 1 out of 15 TTS patients had an acute neurological condition as the underlying triggering factor. Our data emphasize that a wide spectrum of neurological diseases ranging from benign to life-threatening encompass TTS. The high rates of adverse events highlight the need for clinical awareness