Early life stress predicts thalamic hyperconnectivity: A transdiagnostic study of global connectivity.

Early life stress (ELS) is an established risk factor for psychiatric illness and is associated with altered functional connectivity within- and between intrinsic neural networks. The widespread nature of these disruptions suggests that broad imaging measures of neural connectivity, such as global based connectivity (GBC), may be particularly appropriate for studies of this population. GBC is designed to identify brain regions having maximal functional connectedness with the rest of the brain, and alterations in GBC may reflect a restriction or broadening of network synchronization. We evaluated whether ELS severity predicted GBC in a sample (N = 46) with a spectrum of ELS exposure. Participants included healthy controls without ELS, those with at least moderate ELS but without psychiatric disorders, and a group of patients with ELS- related psychiatric disorders. The spatial distribution of GBC peaked in regions of the salience and default mode networks, and ELS severity predicted increased GBC of the left thalamus (corrected p < 0.005, r = 0.498). Thalamic connectivity was subsequently evaluated and revealed reduced connectivity with the salience network, particularly the dorsal anterior cingulate cortex (corrected p < 0.005), only in the patient group. These findings support a model of disrupted thalamic connectivity in ELS and trauma-related negative affect states, and underscore the importance of a transdiagnostic, dimensional neuroimaging approach to understanding the sequelae of trauma exposure.

5-Hz Transcranial Magnetic Stimulation for Comorbid Posttraumatic Stress Disorder and Major Depression.

Current treatment options for posttraumatic stress disorder (PTSD) offer modest benefits, underscoring the need for new treatments. Repetitive transcranial magnetic stimulation (rTMS) depolarizes neurons in a targeted brain region with magnetic fields typically pulsed at low (1 Hz) or high (10 Hz) frequency to relieve major depressive disorder (MDD). Prior work suggests an intermediate pulse frequency, 5 Hz, is also efficacious for treating comorbid depressive and anxiety symptoms. In this chart review study, we systematically examined the clinical and safety outcomes in 10 patients with comorbid MDD and PTSD syndromes who received 5-Hz rTMS therapy at the Providence VA Medical Center Neuromodulation Clinic. Self-report scales measured illness severity prior to treatment, after every 5 treatments, and upon completion of treatment. Results showed significant reduction in symptoms of PTSD (p = .003, effect size = 1.12, 8/10 with reliable change) and MDD (p = .005, effect size = 1.09, 6/10 with reliable change). Stimulation was well tolerated and there were no serious adverse events. These data indicate 5-Hz rTMS may be a useful option to treat these comorbid disorders. Larger, controlled trials are needed to confirm the benefits of 5-Hz protocols observed in this pilot study.

Exposure to childhood trauma is associated with altered n-back activation and performance in healthy adults: implications for a commonly used working memory task.

Previous research suggests that a history of early life stress (ELS) impacts working memory (WM) in adulthood. Despite the widespread use of WM paradigms, few studies have evaluated whether ELS exposure, in the absence of psychiatric illness, also impacts WM-associated brain activity in ways that might improve sensitivity to these ELS effects or provide insights into the mechanisms of these effects. This study evaluated whether ELS affects WM behavioral performance and task-associated activity by acquiring 3T functional images from 27 medication-free healthy adults (14 with ELS) during an N-back WM task that included 0- and 2-back components. Whole brain voxel-wise analysis was performed to evaluate WM activation, followed by region of interest analyses to evaluate relationships between activation and clinical variables. ELS was associated with poorer accuracy during the 2-back (79% ± 19 vs. 92% ± 9, p = 0.049); accuracy and response time otherwise did not differ between groups. During the 0-back, ELS participants demonstrated increased activation in the superior temporal gyrus/insula, left inferior parietal lobule (IPL) (both corrected p < 0.001), and middle temporal and parahippocampal gyrus (MTG/PHG)(corrected p < 0.010). During the 2-back, ELS was associated with greater activation in the IPL, MTG/PHG and inferior frontal gyrus (corrected p < 0.001), with a trend towards precuneus activation (p = 0.080). These findings support previous research showing that ELS is associated with impaired neurobehavioral performance and changes in brain activation, suggesting recruitment of additional cognitive resources during WM in ELS. Based on these findings, ELS screening in future WM imaging studies appears warranted.

5Hz Repetitive transcranial magnetic stimulation to left prefrontal cortex for major depression.

BACKGROUND: Repetitive transcranial magnetic stimulation (rTMS) to left prefrontal cortex at 10Hz is the most commonly utilized protocol for major depressive disorder (MDD). Published data suggests that left sided 5Hz rTMS may be efficacious and well tolerated. OBJECTIVE: We analyzed outcomes in a naturalistic cohort of MDD patients who could not tolerate 10Hz rTMS and were routinely switched to 5Hz. We hypothesized that the efficacy of 5Hz rTMS would be equivalent to 10Hz. METHODS: Records were reviewed for patients (n=98) who received 15 or more acute rTMS treatments. The sample was split based upon the frequency (10 or 5Hz) at which the majority of treatments were delivered. The Inventory of Depressive Symptoms (IDS-SR) and 9-Item Patient Health Questionnaire (PHQ-9) were used to evaluate outcomes. RESULTS: Baseline IDS-SR was higher in the 5Hz (n=27) than in the 10Hz (n=71) group (p<.05), as was frequency of comorbid anxiety (p=.002). Depression outcomes did not differ between groups, and there were no differences in response or remission rates (all p>.1). Statistical power was sufficient to detect small group differences (d=.26). LIMITATIONS: Open-label data in a naturalistic setting. CONCLUSION: Outcomes associated with 5Hz rTMS did not differ from 10Hz, despite higher baseline depressive symptom severity and anxiety in 5Hz patients. 5Hz stimulation may be an alternative treatment option for patients unable to tolerate 10Hz rTMS.