Changes of regional cerebral blood flow after repeated transcranial direct current stimulation in healthy participants: a pilot study.

BACKGROUND: Transcranial direct current stimulation (tDCS) can potentially enhance brain function and cognition in healthy individuals as well as in patients with cognitive impairment. However, neural correlates of repeated tDCS remain relatively unexplored in a healthy population. PURPOSE: To assess the effects of repeated tDCS on regional cerebral blood flow (rCBF) in healthy volunteers in a pilot investigation. MATERIAL AND METHODS: Five healthy adults received bifrontal tDCS to the dorsolateral prefrontal cortex (F3-F4 montage, 1 mA intensity, 30 minutes/session, five sessions/week) over four weeks. All participants underwent brain single-photon emission computed tomography (SPECT) scans at baseline and one week after the last tDCS session. Changes in rCBF were examined using Statistical Parametric Mapping. RESULTS: Resting rCBF was significantly improved in the right superior frontal gyrus at the follow-up (P < 0.001). Adverse events were not reported and the stimulation was well-tolerated. CONCLUSION: Repeated tDCS may be effective for enhancing brain function in healthy participants. Larger sham-controlled studies should be performed to confirm our preliminary findings.

Robotic transcranial magnetic stimulation in the treatment of depression: a pilot study.

There has been an increasing demand for robotic coil positioning during repetitive transcranial magnetic stimulation (rTMS) treatment. Accurate coil positioning is crucial because rTMS generally targets specific brain regions for both research and clinical application with other reasons such as safety, consistency and reliability and individual variablity. Some previous studies have employed industrial robots or co-robots and showed they can more precisely stimulate the target cortical regions than traditional manual methods. In this study, we not only developed a custom-TMS robot for better TMS coil placement but also analyzed the therapeutic effects on depression. Treatment effects were evaluated by measuring regional cerebral blood flow (rCBF) using single-photon emission computed tomography and depression severity before and after rTMS for the two positioning methods. The rTMS preparation time with our robotic coil placement was reduced by 53% compared with that of the manual method. The position and orientation errors were also significantly reduced from 11.17 mm and 4.06° to 0.94 mm and 0.11°, respectively, confirming the superiority of robotic positioning. The results from clinical and neuroimaging assessments indicated comparable improvements in depression severity and rCBF in the left dorsolateral prefrontal cortex between the robotic and manual rTMS groups. A questionnaire was used to determine the patients' feelings about the robotic system, including the safety and preparation time. A high safety score indicated good acceptability of robotic rTMS at the clinical site.

Synthesis of high-density nickel cobalt aluminum hydroxide by continuous coprecipitation method.

Spherical nickel cobalt aluminum hydroxide (Ni(0.80)Co(0.15)Al(0.05)-hydroxide, NCA) was prepared by a continuous coprecipitation method. A new design of the Al solution and the feeding method was applied, which enabled to prevent rapid precipitation of Al(OH)(3) and to obtain spherical NCA with large enough particle size and high density. The active material (LiNi(0.80)Co(0.15)Al(0.05)O(2) or LNCA) prepared from it showed higher tap-density than that made from NCA prepared by general processes, and homogeneity of Al-distribution was also improved. It is expected that the electrode density of lithium ion batteries adopting LNCA could be improved with the new process proposed in this study.