TY - JOUR A1 - Hiew, Shawn A1 - Nguemeni, Carine A1 - Zeller, Daniel T1 - Efficacy of transcranial direct current stimulation in people with multiple sclerosis: a review JF - European Journal of Neurology N2 - Background and purpose Multiple sclerosis (MS) is a chronic inflammatory disease causing a wide range of symptoms including motor and cognitive impairment, fatigue and pain. Over the last two decades, non-invasive brain stimulation, especially transcranial direct current stimulation (tDCS), has increasingly been used to modulate brain function in various physiological and pathological conditions. However, its experimental applications for people with MS were noted only as recently as 2010 and have been growing since then. The efficacy for use in people with MS remains questionable with the results of existing studies being largely conflicting. Hence, the aim of this review is to paint a picture of the current state of tDCS in MS research grounded on studies applying tDCS that have been done to date. Methods A keyword search was performed to retrieve articles from the earliest article identified until 14 February 2021 using a combination of the groups (1) ‘multiple sclerosis’, ‘MS’ and ‘encephalomyelitis’ and (2) ‘tDCS’ and ‘transcranial direct current stimulation’. Results The analysis of the 30 articles included in this review underlined inconsistent effects of tDCS on the motor symptoms of MS based on small sample sizes. However, tDCS showed promising benefits in ameliorating fatigue, pain and cognitive symptoms. Conclusion Transcranial direct current stimulation is attractive as a non-drug approach in ameliorating MS symptoms, where other treatment options remain limited. The development of protocols tailored to the individual's own neuroanatomy using high definition tDCS and the introduction of network mapping in the experimental designs might help to overcome the variability between studies. KW - transcranial direct current stimulation KW - cognitive KW - effects KW - motor KW - multiple sclerosis Y1 - 2022 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-259424 VL - 29 IS - 2 ER - TY - JOUR A1 - Herrmann, Martin J. A1 - Beier, Jennifer S. A1 - Simons, Bibiane A1 - Polak, Thomas T1 - Transcranial Direct Current Stimulation (tDCS) of the Right Inferior Frontal Gyrus Attenuates Skin Conductance Responses to Unpredictable Threat Conditions JF - Frontiers in Human Neuroscience N2 - Patients with panic and post-traumatic stress disorders seem to show increased psychophysiological reactions to conditions of unpredictable (U) threat, which has been discussed as a neurobiological marker of elevated levels of sustained fear in these disorders. Interestingly, a recent study found that the right inferior frontal gyrus (rIFG) is correlated to the successful regulation of sustained fear during U threat. Therefore this study aimed to examine the potential use of non-invasive brain stimulation to foster the rIFG by means of anodal transcranial direct current stimulation (tDCS) in order to reduce psychophysiological reactions to U threat. Twenty six participants were randomly assigned into an anodal and sham stimulation group in a double-blinded manner. Anodal and cathodal electrodes (7 * 5 cm) were positioned right frontal to target the rIFG. Stimulation intensity was I = 2 mA applied for 20 min during a task including U threat conditions (NPU-task). The effects of the NPU paradigm were measured by assessing the emotional startle modulation and the skin conductance response (SCR) at the outset of the different conditions. We found a significant interaction effect of condition × tDCS for the SCR (F(2,48) = 6.3, p < 0.01) without main effects of condition and tDCS. Post hoc tests revealed that the increase in SCR from neutral (N) to U condition was significantly reduced in verum compared to the sham tDCS group (t(24) = 3.84, p < 0.001). Our results emphasize the causal role of rIFG for emotional regulation and the potential use of tDCS to reduce apprehension during U threat conditions and therefore as a treatment for anxiety disorders. KW - transcranial direct current stimulation KW - emotional regulation KW - sustained fear KW - right inferior frontalgyrus KW - NPU Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-146486 VL - 10 IS - 352 ER - TY - JOUR A1 - Manish, Asthana A1 - Nueckel, Katharina A1 - Mühlberger, Andreas A1 - Neueder, Dorothea A1 - Polak, Thomas A1 - Domschke, Katharina A1 - Deckert, Jürgen A1 - Herrmann, Martin J. T1 - Effects of transcranial direct current stimulation on consolidation of fear memory JF - Frontiers in Neuropsychiatric Imaging and Stimulation N2 - It has been shown that applying transcranial direct current stimulation (tDCS) over the dorsolateral prefrontal cortex (DLPFC) influences declarative memory processes. This study investigates the efficacy of tDCS on emotional memory consolidation, especially experimental fear conditioning. We applied an auditory fear-conditioning paradigm, in which two differently colored squares (blue and yellow) were presented as conditioned stimuli (CS) and an auditory stimulus as unconditioned stimulus (UCS). Sixty-nine participants were randomly assigned into three groups: anodal, cathodal, and sham stimulation. The participants of the two active groups (i.e., anodal and cathodal) received tDCS over the left DLPFC for 12 min after fear conditioning. The effect of fear conditioning and consolidation (24 h later) was measured by assessing the skin conductance response (SCR) to the CS. The results provide evidence that cathodal stimulation of the left DLPFC leads to an inhibitory effect on fear memory consolidation compared to anodal and sham stimulation, as indicated by decreased SCRs to CS+ presentation during extinction training at day 2. In conclusion, current work suggests that cathodal stimulation interferes with processes of fear memory consolidation. KW - transcranial direct current stimulation KW - dorsolateral prefrontal cortex KW - fear conditioning KW - fear memory consolidation Y1 - 2013 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-97294 ER -