Mindful Breathing and tDCS for Depression

Change in dorsolateral prefrontal cortex connectivity with the salience network and the default mode using functional MRI compared between treatment groups: Right Amygdala and left DLPFC. Lower connectivity may represent a reduced tendency to engage in maladaptive, repetitive negative thinking.

For r-values, 0 represents that the timeseries of the respective ROIs are not correlated. A better outcome may be indexed by lower connectivity (e.g., negative R values), which may represent a greater ability of the DLPFC to downregulate the amygdala and, which in turn may reduce the tendency to engage in maladaptive, repetitive negative thinking.

Change in dorsolateral prefrontal cortex connectivity with the salience network and the default mode using functional MRI compared between treatment groups: default mode network and left DLPFC. Lower DLPFC and DMN connectivity may represent adaptive switching between thinking states to focus on a task at hand or to engage in more reflective, introspective thinking patterns.

For r-values, 0 represents that the timeseries of the respective ROIs are not correlated. Change in dorsolateral prefrontal cortex connectivity with the salience network and the default mode using functional MRI compared between treatment groups: default mode network and left DLPFC. A better outcome may be indexed by lower DLPFC and DMN connectivity (e.g., negative R values), which may represent adaptive switching between thinking states to focus on a task at hand or to engage in more reflective, introspective thinking patterns.

Montgomery-Åsberg Depression Rating Scale - self-assessment (MADRS-S) measures change in severity of depression symptoms over time. Treatment response will be measured using the MADRS-S and a ~50% reduction in depression severity, i.e. total MADRS-S score, will indicate a positive response to treatment.

The scale includes 9 items that are rated by participants on a 4-point Likert scale ranging from 0 - 3. Half-point scores are also possible, i.e 0.5, 1.5, 2.5. Participants rate their symptoms from over the past 3 days and the range of total possible scores is 0 - 27, with a higher score indicating greater severity of symptoms. Bondolfi et al. (2010) found good internal consistency for the MADRS-S, as well as good concurrent validity between the MADRS (clinician administered) and the MADRS-S. Lastly, the MADRS-S was found to be sensitive to change in depression symptoms over time.

Mindful Attention and Awareness Scale (MAAS) measures presence or absence of awareness of what is happening in the present. The MAAS consists of 15 items. Participants are requested to rate each item according to a 6-point Likert scale with the following options: "Almost Always", "Very Frequently", "Somewhat Frequently", "Somewhat Infrequently", "Very Infrequently", and "Almost Never". Previous study reported that the MAAS was internally consistent and a reliable measure. MAAS score ranges from 1 to 6, with a higher score indicating a greater awareness of inner experiences and mindfulness. In the present study, an increase in the total MAAS score would indicate an increase in presence of awareness of what is happening in the present.

Ruminative Response Scale (RRS) measures rumination, which refers to thoughts and behaviors centered around one's symptoms and their causes, as well as potential consequences. Nolen-Hoeksema, Morrow, & Fredrickson (1993) reported that ruminative thoughts correlated with depressed mood. They further reported a consistency in ruminative responses over a 30-day period. The RRS will be used to measure changes in rumination in the present study. The measure consists of a total of 22 statements that describe ruminative thoughts and participants are requested to rate each statement on a scale of 1 - 4, 1 being "Almost Never" and 4 being "Almost Always". Change in rumination corresponds with a change in the total RRS score.

Total scores range from 22 to 88.

Freiburg Mindfulness Inventory (FMI) assesses curious attitude toward the mindfulness experience. The FMI contains 14 statements related to mindfulness experiences. Participants are requested to rate each statement according to a 4-point Likert scale ranging from "Rarely" to "Almost Always". An increase in the FMI total score would indicate an increase in mindfulness. Walach et al. (2006) reported that the FMI is a valid and reliable measure of mindfulness.

Total scores range from 14 to 56.

Measure of occurrence of negative side-effects from treatment. Side effects will be collected via participant self-report. Number of serious and non-serious adverse events will be considered in determining safety of the treatment. A higher number of adverse events will indicate lower treatment safety.

Number of participants enrolled. A high number of participants enrolled will indicate a higher level of tolerability of the treatment.

Number of participants who drop-out due to inability to tolerate treatment. A high number of participant drop-outs will indicate a lower level of tolerability of the treatment.