(cTBS) applied over M1 to an inter-regional priming protocol. In protocol 1, sham cTBS was administered to the left-dorsolateral prefrontal cortex (DLPFC), then active cTBS over the ipsilateral FDI “hot spot” (sham-M1). In protocol 2, active cTBS was applied over the left-DLPFC, then ipsilateral M1 (DLPFC-M1). cTBS trains were separated by 10 mins with TEPs taken before, in-between, and after each round. TMS applied over the left shoulder was included to control for sensory contamination. Ten right- handed participants (age: M ¼ 21.90; SD ¼ 5.62) attended 2 sessions separated by at least 1 week. Preliminary results indicate sham-M1 and DLPFC-M1 differentially modulates TEPs over and above shoulder stimu- lation. Sham-M1 stimulation reduces the P30, whereas DLPFC-M1 stimu- lation potentiates the P60. Both Sham-M1 and DLPFC-M1 attenuate the N100 response with greater reductions observed in the latter. Although shoulder stimulation evoked similar TEPs to scalp stimulation, responses following peripheral stimulation remained largely unchanged across all stimulation protocols and time points. TMS-EEG can be used to measure regionally specific, cortical responses to standard and priming cTBS. In- clusion of an active control condition can assist in isolating the effects specific to the target paradigm. Keywords: transcranial magnetic stimulation, continuous theta burst stimulation, priming, electroencephalography 159 TRANSCRANIAL NEAR INFRA RED LIGHT IMPROVES NAMING PERFORMANCE A. Jahan 1 , S. Iranfar 2 . 1 Tabriz University of Medical sciences, Iran, Islamic Republic of; 2 University of Cote d'azur, France Background: Near-infra red light (NIL) irradiation on scalp could modulate cognitive performance in healthy and clinical population. [i] As we know, there is no study on the effectiveness of NIL on language performance. In this current preliminary study, we investigated possible effect of NIL irradiation on naming performance in healthy people. Methods: Thirty healthy students participated in this study. NIL was irradiated by 850nm LED over Brodmann area 47 (F7). Continuous light with 60 joule energy was applied for 4 minutes and 48 seconds. In a random allocation, 14 students were included in sham group and 16 in real group. To examine the naming performance, two parallel naming tests (r¼0.95), each consisting of 30, line draws were used before and after treatment (real/sham) in a computerized chronometric task. Outcome was naming reaction times. Results: A repeated measures ANOVA was used to test possible interaction of. Test showed significant interaction Time (pre/post) by Group (Real/ Sham) [F(1, 29)¼15.52, p¼ 0.038] (Fig. 1). Posthoc test showed significant decrease of RT in Real intervention group (p<0.05). Conclusion: This preliminary study showed significant increase in naming speed in healthy people. This can indicate effectiveness of NIL LED source on modulating linguistic abilities in healthy and clinical population. Figure 1ĂMargaret A. Naeser et al, (2011), Improved Cognitive Function After Transcranial, Light-Emitting Diode Treatments in Chronic, Traumatic Brain Injury: Two Case Reports, Photomedicine and Laser Surgery journal, Vol. 29, No. 5 Martin PI (2016), Transcranial, Red/Near-Infrared Light-Emitting Diode Therapy to Improve Cognition in Chronic Traumatic Brain Injury, Photo- medicine and Laser Surgery journal, vol 34, No12 Jugta Khuman et al (2012), Low-Level Laser Light Therapy Improves Cognitive Deficits and Inhibits Microglial Activation after Controlled Cortical Impact in Mice, Journal of Neurotrauma, Vol 29, No 2 Keywords: Infra Red light, Naming performance 160 CATHODAL TRANSCRANIAL DIRECT CURRENT STIMULATION OVER THE PRIMARY MOTOR CORTEX INDUCES NONLINEAR NEUROPLASTICITY WITH MODULATIONS OF INTENSITY AND DURATION M Mosayebi Samani 1, 2 , D. Agboada 3, 2 , A. Jamil 2 , M. Kuo 2 , M. Nitsche 4, 2 . 1 Institute of Biomedical Engineering and Informatics, Ilmenau University of Technology, Ilmenau, Germany; 2 Leibniz Research Centre for Working Environment and Human Factors, Germany; 3 International Graduate School of Neuroscience, IGSN, Ruhr University Bochum, Bochum, Germany; 4 Department of Neurology, University Hospital Bergmannsheil, Bochum, Germany Transcranial direct current stimulation (tDCS) can non-invasively induce polarity-dependent excitability alterations in the human motor cortex lasting more than an hour after stimulation. Clinical application with encouraging results have been reported in several pilot studies, but the optimal stimulation protocols remain to be determined. We systemically explored the association between tDCS parameters (intensity, duration) and induced after-effects on motor cortex excitability. Cathodal tDCS was applied in three different intensities (1, 2 and 3 mA) and durations (15, 20 and 30mins) on 16 young healthy subjects and the after-effects were monitored with TMS-induced motor evoked potentials (MEP) until the next day evening after stimulation. The results revealed that 1 mA  15 min, 1 mA  30 min and 3 mA  20 min induced LTD-like plasticity, while LTP-like plasticity was observed after 2 mA stimulation for 20 min. It was shown that there is a nonlinear modulatory effect of stimulation in- tensity/duration on neuroplasticity , which might be caused by calcium dynamics relevant for long-term depression and potentiation induction. Our study thus provides further insights on the dependency of tDCS- induced neuroplasticity on the stimulation parameters, and therefore delivers crucial information for future clinical applications. Keywords: Neuroplasicity, noninvasive brain stimulation, Transcranial direct cortical stimulation (tDCS), transcrancial magnetic stimulation, primary motor cortex 161 SINGLE SESSION ANODAL TRANSCRANIAL DIRECT CURRENT STIMULATION ALTERS THE PREFRONTAL AND TEMPORAL ALPHA ASYMMETRICAL INDEXES IN HEALTHY INDIVIDUAL PERFORMING A VISUAL ATTENTION TASK A. Yadollahpour , M. Jalilifar. Ahvaz Jundishapur University of Medical Sciences, Iran, Islamic Republic of Introduction: EEG asymmetry index (AI) of specific brain regions is reportedly associated with attentional and cognitive activities. Trans- cranial direct current stimulation (tDCS) can affect attentional perfor- mance in healthy individuals. The present study investigates the effects of a single session anodal tDCS over prefrontal cortex (PFC) on EEG alpha AIs of different brain regions in healthy individuals. Methods: Participants (n¼13) were randomly selected among healthy students (mean age: 23.63±2.31 years) from Ahvaz Jundishapur University of Medical Sciences, Iran. The participants underwent a single session of 1mA (current density: 50 mA/cm 2 ) anodal tDCS (anode over Fp1-Fp2 and cathode over neck base) for 20 minutes. In all subjects, before and immediately after tDCS, the EEG (10-20 placement) was recorded, while the subjects were performing attentional network task (ANT). The alpha AIs were comparatively assessed prior and post tDCS for prefrontal(FP1- FP2), mid- and lateral-frontal(F3-F4 and F7-F8), temporal( T3-T4), and parietal(P3-P4) regions. Results: Prefrontal lobe showed the greatest changes in alpha AI (-0.051 versus 0.068), followed by temporal lobe (0.079 versus 0.13). After tDCS, Abstracts / Brain Stimulation 12 (2019) 385e592 405