Transcranial direct current stimulation improves the QT variability index and autonomic cardiac control in healthy subjects older than 60 years

Abstract

BackgroundNoninvasive brain stimulation technique is an interesting tool to investigate the causal relation between cortical functioning and autonomic nervous system (ANS) responses.ObjectiveThe objective of this report is to evaluate whether anodal transcranial direct current stimulation (tDCS) over the temporal cortex influences short-period temporal ventricular repolarization dispersion and cardiovascular ANS control in elderly subjects.Subjects and methodsIn 50 healthy subjects (29 subjects younger than 60 years and 21 subjects older than 60 years) matched for gender, short-period RR and systolic blood pressure spectral variability, QT variability index (QTVI), and noninvasive hemodynamic data were obtained during anodal tDCS or sham stimulation.ResultsIn the older group, the QTVI, low-frequency (LF) power expressed in normalized units, the ratio between LF and high-frequency (HF) power, and systemic peripheral resistances decreased, whereas HF power expressed in normalized units and α HF power increased during the active compared to the sham condition (P<0.05).ConclusionIn healthy subjects older than 60 years, tDCS elicits cardiovascular and autonomic changes. Particularly, it improves temporal ventricular repolarization dispersion, reduces sinus sympathetic activity and systemic peripheral resistance, and increases vagal sinus activity and baroreflex sensitivity.

Deontological morality can be experimentally enhanced by increasing disgust: A transcranial direct current stimulation study

“…The present study also replicated results from previous studies conducted in favor of the notion that electrical stimulation applied over the temporal lobe (T3) can reach surrounding deep cerebral areas like the insula (Lang et al, 2005), with significant effects on parasympathetic modulation of HR (Montenegro et al, 2011;Okano et al, 2015;Petrocchi et al, 2017;Piccirillo et al, 2016). However, none of these previously conducted studies interpreted the increase in HRV that followed tDCS stimulation as due to the elicitation of the emotion of disgust.…”

“…Drawing on preexisting neuroimaging evidence on the association between deontological guilt and brain regions associated with disgust (e.g., the insula), we used transcranial direct current stimulation (tDCS) to indirectly stimulate the insula. A series of previous studies show that with this methodology it is possible to stimulate the areas located just below the temporal cortex, comprising the insula by the use of tDCS over T3 (Montenegro et al, 2011;Okano et al, 2015;Petrocchi et al, 2017;Piccirillo et al, 2016). If deontological -but not altruistic-guilt is strictly connected with the emotion of disgust, and they share part of the same neural network, i.e.…”

Time‐ and frequency‐domain analysis of repolarization phase during recovery from exercise in healthy subjects

“…To calculate repolarization variables a template method has been used 17 . We designed and produced a software for data acquisition, storage, and analysis with the LabView program (National Instruments), which applies the technical recommendation of consensus guidance endorsed by European Heart Rhythm Association jointly with the European Society of Cardiology Working Group on cardiac cellular electrophysiology, as described in detail in previous papers 1,2,8‐13,18,19 …”

“…The repolarization phase is a complex phenomenon, with various ion channels and transporter mechanisms most of them under a strong autonomic modulation 4,5 . In fact, all the sodium, calcium, and potassium channels are able to adapt the QT duration in function of previous diastolic interval duration 6 but also of the autonomic control 7‐13 . Previous studies analyzed the repolarization phase during the first 10 minutes of exercise recovery in patients with congenital long QT syndrome 14‐16 focusing on ECG markers obtained from peak to the progressive reduction of exercise heart rate.…”

Effects of Transcranial Direct Current Stimulation (tDCS) and Exercises Treadmill on Autonomic Modulation of Hemiparetic Patients Due To Stroke—Clinic Test, Controlled, Randomized, Double-Blind

“…Piccirillo et al (31) observed an improvement of temporal dispersion of myocardium, reduction in sympathetic sinus control, and increased vagal modulation in healthy elderly, after the single application of tDCS for 15 min, intensity 2 mA, over the left temporal area (T3) associated to breathing exercises. This differentiation of results observed in our study may have occurred for being a different population, and that already presents an autonomic modulation alteration, as described by Dutsch et al (8) that report that independent of the ischemia side, the patient's post sever stroke present a parasympathetic cardiac deficit.…”