Theta Burst Stimulation in Young Adults With Depression

This measure captures brain function in the dorsomedial prefrontal cortex (dmPFC) based on blood oxygen level dependent (BOLD) response measured using functional magnetic resonance imaging (fMRI) during a reward task. Data are analyzed using Statistical Parametric Mapping. Magnitude of dmPFC response is in arbitrary units, with higher values reflecting higher activation. Theoretical minimum and maximum scores do not exist. Study hypotheses predict that dmPFC will decrease (based on statistical significance) with continuous TBS.

Time frame: Task fMRI is conducted after each of 3 TBS sessions (intermittent, continuous, sham; in randomized, counterbalanced order) at approx 3, 5, and 7 weeks after study entry.

Population: Cases included in analysis are those from participants who completed all study procedures (i.e., all TMS sessions, all MRI scans), had available data, and passed data quality criteria

Self-reported pleasant mood was measured with the Positive Affect (PA) scale of the Positive and Negative Affect Schedule (PANAS). This scale consists of a number of words that describe different feelings and emotions, participants are instructed to read each item and then mark to which extent they have felt like this in the past few hours. The PA scale contains 10 items, with each item rated on a 5-point scale of 1 (very slightly or not at all), 2 (a little), 3 (moderately), 4 (quite a bit), or 5 (extremely). Higher scores indicate greater PA. The total PA score is calculated by finding the sum of the 10 positive items. Scores range from 10-50. A higher score indicates higher intensity of positive affect. The PANAS PA data analyzed were from administrations pre- and post-TBS at visits #3-5 (approximately 30 minutes before and 1 hour after TBS administration).

Time frame: pre and post each of 3 TBS administrations, with TBS lasting up to 190 seconds. cTBS, iTBS, and sham TBS each occurred in a single day.

Population: Only participants who completed the PA measure at all time points (pre/post each condition, all 3 conditions) were included in analyses.

Outcome measure is assessed with functional magnetic resonance imaging (fMRI), in which brain function is recorded during a reward task. Functional connectivity between 2 regions of neural reward circuitry, the ventral striatum (VS) and the dorsomedial prefrontal cortex (dmPFC), is computed using general psychophysiologic interaction for this pair of regions in Statistical Parametric Mapping software. FC data are in arbitrary units, with higher values reflecting higher degree of coordination between the regions. Theoretical minimum and maximum scores do not exist. Higher scores do not represent better or worse outcomes or change in health. Based on study hypotheses, FC is predicted to decrease with continuous TBS, based on significance of statistical tests.

Time frame: Task fMRI is conducted after each of 3 TBS sessions (intermittent, continuous, sham; in randomized, counterbalanced order). Sessions occur at approx 3, 5, and 7 weeks after study entry.

Population: Cases included in analysis are those from participants who completed all MRI scans, had available fMRI data, and had data that passed quality criteria