Transcranial direct current stimulation (tDCS).

<p>Time course of direct current strength in the different tDCS conditions.</p

Treatment outcome.

1<p>Analysis of variance.</p>2<p>Transcranial direct current stimulation.</p>3<p>Tinnitus Questionnaire, total score.</p>4<p>Tinnitus Questionnaire, subscale emotional + cognitive distress.</p>5<p>Tinnitus Handicap Questionnaire, total score.</p>6<p>Tinnitus Handicap Inventory, total score.</p><p>*Statistically significant.</p

Study design.

<p>For each participant, the study took 45 days (4 days of pre-treatment waiting, 10 days of treatment, and 31 days of post-treatment observation). During the initial 5 days of treatment, transcranial direct current stimulation (tDCS) and the tailor-made notched music training (TMNMT) were applied simultaneously; during the remaining 5 days of treatment, only TMNMT was applied. Throughout the study, perceived tinnitus-related distress data were sampled repeatedly.</p

Changes in Tinnitus Handicap Questionnaire (THQ) values during and after treatment.

<p>Changes in THQ total scores relative to the baseline scores as functions of time (after tDCS¹ + TMNMT² vs. after TMNMT only vs. obs3 vs. obs31) and tDCS condition (anodal group vs. cathodal group vs. sham group). Bars represent means, error bars denote standard errors of the mean. Negative values reflect improvement. Dashed black lines indicate significant post-hoc tests. *p<.05, **p<.01; ¹Transcranial direct current stimulation; ²Tailor-made notched music training.</p

Grand-averaged event-related potentials.

<p>ERPs from eleven standard electrode positions are presented, plotted by priming condition in an interval stretching from 200</p

Music spectra.

<p>Schematic frequency spectra of original music (solid line) and flattened notched music (dashed dotted line).</p

Results from the EEG source analysis.

<p>a) Global Power of estimated EEG source activations across all test dipoles. b) Global Power of <i>F</i>-values for the main effect <i>Semantic Relation</i> from a pointwise repeated-measurement ANOVA (based on half the participant sample). The interval of interest selected for second-order analysis is indicated by dotted lines. c) Statistical parametric maps (SPMs) of the <i>F</i>-values for the main effect of <i>Semantic Relation</i> from the same pointwise repeated measurement ANOVA (mean <i>F</i>-value in the interval of 440 – 590 ms after picture onset, projected onto a standard cortical surface). The upper row shows SPMs for the first half of participants, on which selection of the interval and ROIs was based. Dipole clusters selected for second-order analysis are marked in green. For comparison, the lower row shows SPMs for the entire set of participants. d) Mean L2-MNE source activations from the second half of participants for the selected interval and ROIs, plotted by priming condition [colors as in a)]. Error bars represent within-participant standard errors following Cousineau <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0084029#pone.0084029-Cousineau1" target="_blank">[59]</a>.</p

Comparison of baseline data.

<p>Comparison of baseline data.</p

Modulatory Effects of Attention on Lateral Inhibition in the Human Auditory Cortex

<div><p>Reduced neural processing of a tone is observed when it is presented after a sound whose spectral range closely frames the frequency of the tone. This observation might be explained by the mechanism of lateral inhibition (LI) due to inhibitory interneurons in the auditory system. So far, several characteristics of bottom up influences on LI have been identified, while the influence of top-down processes such as directed attention on LI has not been investigated. Hence, the study at hand aims at investigating the modulatory effects of focused attention on LI in the human auditory cortex. In the magnetoencephalograph, we present two types of masking sounds (white noise vs. withe noise passing through a notch filter centered at a specific frequency), followed by a test tone with a frequency corresponding to the center-frequency of the notch filter. Simultaneously, subjects were presented with visual input on a screen. To modulate the focus of attention, subjects were instructed to concentrate either on the auditory input or the visual stimuli. More specific, on one half of the trials, subjects were instructed to detect small deviations in loudness in the masking sounds while on the other half of the trials subjects were asked to detect target stimuli on the screen. The results revealed a reduction in neural activation due to LI, which was larger during auditory compared to visual focused attention. Attentional modulations of LI were observed in two post-N1m time intervals. These findings underline the robustness of reduced neural activation due to LI in the auditory cortex and point towards the important role of attention on the modulation of this mechanism in more evaluative processing stages.</p></div

Subjective music perception.

1<p>Arithmetic mean (standard deviation); range: 0–100.</p>2<p>Transcranial direct current stimulation.</p