High-Definition transcranial direct current stimulation (HD-tDCS) is a non-invasive electrical stimulation used for modulation of brain function. At present, relevant researches mainly focused on the modulation effects of stimulation, while ignored the neurophysiological mechanism of stimulation process. The main targets of this study were to investigate the effect of stimulation combined with working memory training on brain networks connectivity and information transmission efficiency when the stimulus was applied on left dorsolateral prefrontal cortex (LDLPFC). Partial Directed Coherence (PDC) task-mode brain network analysis results of 34 participants showed that brain networks connectivity in α and β band significantly enhanced, but sham group was less than active group. In addition, active group found that the brain network attribute parameters, such as the clustering coefficient and global efficiency, showed varying degrees of improvement, while there was no significant change in sham group. The above results showed that HD-tDCS acting on working memory training could enhance the brain network connectivity and improve the efficiency of brain clustering and information transmission to a greater extent.Phase-amplitude coupling (PAC), in which the amplitude of a faster neural oscillation couples to the phase of a slower rhythm, is one of the most common representations of complex neuronal rhythmic activities. In a healthy brain, PAC accompanies cognitive function, and abnormal patterns of PAC have been linked to several neurological disorders. Among the various brain neuromodulation techniques, phase-dependent stimulation has a strong potential to modulate PAC levels. In this study, we utilize a computational model in the NEURON environment based on a detailed mathematical model of neuronal populations, consisting of networks with both excitatory and inhibitory neurons, to simulate PAC generation. The model was then used to investigate the modulatory effects of phase-dependent stimulation on the generated PAC. Simulated data from the model shows that stimulation locked to the phase of slower rhythms increased PAC level during stimulation. These results demonstrate the capacity of phase-dependent stimulation to modulate PAC, which could allow for applications in the treatment of neurological disorders associated with abnormal PAC, such as Parkinson's disease.Clinical Relevance- Analyzing the origins of neuronal PAC and developing a brain stimulation technique for modulating the level of PAC can facilitate the development of novel treatment methods for neurological disorders associated with abnormal cross-frequency coupling.Sleep spindles are transient oscillations in the brain related to sleep consolidation and memory. We investigated if brief, localized electrical pulses could perturb spindles on five human patients with intracerebral electrodes implanted for clinical purpose. We used a closed-loop setup to specifically detect spindles and stimulate in real-time during these events. Stimulation latency was 200-400 ms following spindle onset. Analyzing the intracranial electro-encephalographic (iEEG) data both locally and globally, we found, in two of the patients, that single pulse stimulation could stop the spindles locally. Spindles were shorter than those without stimulation and a decrease in power at the same frequency as spindles was observed following stimulation.Clinical Relevance- This study shows that brief and precise electrical stimulation may be used to modulate oscillatory behavior of the human brain. Applied to sleep spindles, further studies may establish that single pulses applied in a closed-loop manner could be used to modulate memory and could help understand effect of neuromodulation in sleep disruption.Infrared neural stimulation (INS) is an optical stimulation technique which uses coherent light to stimulate nerves and neurons and which shows increased spatial selectivity compared to electrical stimulation. https://www.selleckchem.com/products/ly2157299.html This could improve deep brain, high channel count, or vagus nerve stimulation. In this study, we seek to understand the wavelength dependence of INS in the near-infrared optical window. Rat sciatic nerves were excised ex vivo and stimulated with wavelengths between 700 and 900 nm. Recorded compound nerve action potentials (CNAPs) showed that stimulation was maximized in the 700 nm window despite comparable laser power levels across wavelengths. Computational models demonstrated that wavelength-based activation dependencies were not a result of passive optical properties. This data demonstrates that INS is both wavelength and power level dependent, which inform stimulation systems to actively target neural microcircuits in humans.Electrical stimulation of the vagus nerve has been shown to enhance cortical plasticity and may benefit upper extremity rehabilitation following stroke. As an initial step towards assessing the potential of other craniocervical nerves as neuromodulation targets during rehabilitation, we explored the ability of non-invasive stimulation of cervical spine afferents, paired with a proprioceptive discrimination task, to improve sensory function in neurologically intact human subjects. On each trial, subjects' arms were moved by a robot from a test position, along a random path, to a judgment position located 1-4 cm away. Subjects responded 'same' if the judgment position was the same as the test or 'different' if it was not. These responses were used to compute proprioceptive sensitivity and bias. Three groups of 20 subjects received transcutaneous electric nerve stimulation to the C3/C4 cervical spine at one of three frequencies (30 Hz, 300 Hz, 3 kHz) for 10 minutes prior to task performance. A fourth group served as a sham. We found a statistically significant interaction between stimulation frequency and displacement distance on proprioceptive sensitivity. In summary, stimulation of cervical spine afferents may enhance arm proprioceptive function, though in unimpaired subjects these gains depend on both stimulation frequency and discrimination distance.Clinical Relevance- This study provides preliminary data on the potential for non-invasive stimulation of cervical spine afferents to enhance recovery of function following stroke and other neurological disorders.