Faculty Bibliography

BACKGROUND:Neuropsychiatric disorders are a leading source of disability and require novel treatments that target mechanisms of disease. As such disorders are thought to result from aberrant neuronal circuit activity, neuromodulation approaches are of increasing interest given their potential for manipulating circuits directly. Low intensity transcranial electrical stimulation (tES) with direct currents (transcranial direct current stimulation, tDCS) or alternating currents (transcranial alternating current stimulation, tACS) represent novel, safe, well-tolerated, and relatively inexpensive putative treatment modalities. OBJECTIVE:This report seeks to promote the science, technology and effective clinical applications of these modalities, identify research challenges, and suggest approaches for addressing these needs in order to achieve rigorous, reproducible findings that can advance clinical treatment. METHODS:The National Institute of Mental Health (NIMH) convened a workshop in September 2016 that brought together experts in basic and human neuroscience, electrical stimulation biophysics and devices, and clinical trial methods to examine the physiological mechanisms underlying tDCS/tACS, technologies and technical strategies for optimizing stimulation protocols, and the state of the science with respect to therapeutic applications and trial designs. RESULTS:Advances in understanding mechanisms, methodological and technological improvements (e.g., electronics, computational models to facilitate proper dosing), and improved clinical trial designs are poised to advance rigorous, reproducible therapeutic applications of these techniques. A number of challenges were identified and meeting participants made recommendations made to address them. CONCLUSIONS:These recommendations align with requirements in NIMH funding opportunity announcements to, among other needs, define dosimetry, demonstrate dose/response relationships, implement rigorous blinded trial designs, employ computational modeling, and demonstrate target engagement when testing stimulation-based interventions for the treatment of mental disorders.

BACKGROUND: Cognitive impairment is a common and troubling feature of pediatric-onset multiple sclerosis (POMS). Brief cognitive assessment in the outpatient setting can identify and longitudinally monitor cognitive involvement so that early intervention is possible. OBJECTIVES: The goal of this study was to measure the sensitivity of two cognitive assessment approaches that are brief, repeatable, and suitable for clinical practice and for multicenter investigation. METHODS: Participants with POMS ( n = 69) were consecutively evaluated as part of outpatient neurologic visits and compared to healthy control participants (HC, n = 66) using the Brief International Cognitive Assessment for MS (BICAMS) approach and timed information processing measures from Cogstate, a computer-based assessment. RESULTS: There was strong agreement in the detection rate of impairment between both assessments, with 26% for the BICAMS and 27% for Cogstate. Two of the Cogstate tasks were the most sensitive individual measures. CONCLUSION: Both the BICAMS and Cogstate timed processing measures offer practical, sensitive, and standardized approaches for cognitive screening assessment in POMS.

[This corrects the article DOI: 10.1371/journal.pone.0177177.].

The remotely supervised tDCS (RS-tDCS) protocol enables participation from home through guided and monitored self-administration of tDCS treatment while maintaining clinical standards. The current consensus regarding the efficacy of tDCS is that multiple treatment sessions are needed to observe targeted behavioral reductions in symptom burden. However, the requirement for patients to travel to clinic daily for stimulation sessions presents a major obstacle for potential participants, due to work or family obligations or limited ability to travel. This study presents a protocol that directly overcomes these obstacles by eliminating the need to travel to clinic for daily sessions. This is an updated protocol for remotely supervised self-administration of tDCS for daily treatment sessions paired with a program of computer-based cognitive training for use in clinical trials. Participants only need to attend clinic twice, for a baseline and study-end visit. At baseline, participants are trained and provided with a study stimulation device, and a small laptop computer. Participants then complete the remainder of their stimulation sessions at home while they are monitored via videoconferencing software. Participants complete computerized cognitive remediation during stimulation sessions, which may serve a therapeutic role or as a "placeholder" for other computer-based activity. Computers are enabled for real-time monitoring and remote control by study staff. Outcome measures that assess feasibility and tolerance are administered remotely with the aid of visual analogue scales that are presented onscreen. Following completion of all RS-tDCS sessions, participants return to clinic for a study end visit in which all study equipment is returned. Results support the safety, feasibility, and scalability of the RS-tDCS protocol for use in clinical trials. Across 46 patients, 748 RS-tDCS sessions have been completed. This protocol serves as a model for use in future clinical trials involving tDCS.