F160. Investigation of the effects of transcranial direct current stimulation and neurofeedback by continuous performance test and beck inventories

Abstract

Transcranial direct current stimulation (tDCS) method is a noninvasive neuromodulation technique based on weak direct current stimulation through the scalp. Neurofeedback (NFB) is a learning strategy which may help to alter brain wave parameters of a person by giving electroencephalography (EEG) feedback via special developed computer programs. Based on the aforementioned evidence, the study was designed to examine primarily the possible fascinating and supportive effects of tDCS application in addition to NFB training on healthy volunteers. Secondly, we aimed to examine brain wave parameters of by giving EEG feedback alteration by Continuous Performance Test (CPT), Beck Inventories (BI) used in order to measure; the selective attention, response time and suppression. Sixteen healthy volunteers were divided into two groups consisting of eight subjects. One of the groups were trained by sensorimotor rhythm (SMR) NFB training; 2 days per week, 10 sessions of 30 min, other group received 10 min tDCS before each NFB training session. CPT, BI were used in order to measure the selective attention, response time and suppression. Obtained EEG band values and rates were evaluated offline. According to statistical analyses, average of depression scores of NFB + tDCS group (7.000 ± 4.07) was decreased compared to before (9,625 ± 5.60) NFB + tDCS practice, it was significantly decreased when compared with statistical analyze of t-test (t (7) = 2628, p < .05). After trainings, the results of CPT were compared with repeated measure ANOVA.Sessions were analyzed by comparing 1st, 2nd, 5th and 10th practice results. Although there was no significant difference of right answers of the group of NFB (F (4,28) = 2215, p = .093), NFB + tDCS were significantly increased (F (4,28) = 6557, p = .001). Each groups CPT score were compared by repeated measures of ANOVA, statistically significance was found between the correct response latencies of the NFB group (F (4,28) = 3282, p = .025) and NFB + tDCS group (F(4,28) = 3143, p = .030). When the frequency bands were compared between the NFB training group with post hoc Bonferroni pairwise comparisons showed that difference was significant between 1st practice (1.515 ± .39) and at the 10th application (1.996 ± .42 (p = .002). When the inter-application of frequency bands at the group of NFB + tDCS statistically significant between the first 1th stimulation (10.165 ± 1.34) and 10th stimulation (14.128 ± 1.72)(p = .012), The difference on theta/beta band is significant at 2th practice (2.074 ± .098) to 10th practice (1.824 ± .084) (.013). While NFB + tDCS had significance at theta/beta ratios and alpha band amplitudes, NFB group had significance at theta/SMR ratios. Results suggest that NFB training shows its effects at the end of 10 sessions, and additional use of tDCS did not accelerate improvement as expected. However, its therapeutic effect on anxiety and depression scores and inhibition deficits of subjects were clear.