Drug-induced malfunction of nucleus accumbens (NAc) neurons underlies a key pathophysiology of drug addiction. Drug-induced changes in intrinsic membrane excitability of NAc neurons are thought to be critical for producing behavioral alterations. Previous studies demonstrate that, after short-term (2 d) or long-term (21 d) withdrawal from noncontingent cocaine injection, the intrinsic membrane ...

Transcranial direct current stimulation (tDCS) has been reported to be a promising technique for consciousness improvement for patients with disorders of consciousness (DOC). However, there has been no direct electrophysiological evidence to demonstrate the efficacy of tDCS on patients with DOC. Therefore, we aim to measure the cortical excitability changes induced by tDCS in patients with DOC,...

Transcranial direct current stimulation (tDCS) is a noninvasive technique that modulates the excitability of neurons within the motor cortex (M1). Although the aftereffects of anodal tDCS on modulating cortical excitability have been described, there is limited data describing the outcomes of different tDCS intensities on intracortical circuits. To further elucidate the mechanisms underlying th...

Aging affects all levels of neural processing, including changes of intracortical inhibition and cortical excitability. Paired-pulse stimulation, the application of two stimuli in close succession, is a useful tool to investigate cortical excitability in humans. The paired-pulse behavior is characterized by the second response being significantly suppressed at short stimulus onset asynchronies....

During motor imagery, to estimate changes in excitability of flexor carpi radialis muscle motoneurons of the spinal and cortical levels, electrical stimuli for recording H-reflex and transcranial magnetic stimulation (TMS) for recording motor evoked potentials (MEPs) were used. In the absence of movement or detectable EMG activity during motor imagery, there was an increase in cortical excitabi...

BACKGROUND Premotor cortical regions (PMC) play an important role in the orchestration of motor function, yet their role in compensatory mechanisms in a disturbed motor system is largely unclear. Previous studies are consistent in describing pronounced anatomical and functional connectivity between the PMC and the primary motor cortex (M1). Lesion studies consistently show compensatory adaptive...

Transcranial magnetic stimulation (TMS) of human occipital and posterior parietal cortex can give rise to visual sensations called phosphenes. We used near-threshold TMS with concurrent electroencephalography (EEG) recordings to measure how oscillatory brain dynamics covary, on single trials, with the perception of phosphenes following occipital and parietal TMS. Prestimulus power and phase, pr...

To examine individual or combined effects of static stretch and explosive contraction on quadriceps spinal-reflex excitability (the peak Hoffmann’s reflex normalized by the motor-response) latency times motor-response. Fourteen healthy young males randomly experienced four conditions (stretch, contraction, + control—no intervention). For condition, three sets a 30 s hold using modified Thomas t...