Towards precise brain stimulation: Is electric field simulation related to neuromodulation?Recent research on neural and behavioral consequences of transcranial direct current stimulation (tDCS) has highlighted the impact of individual factors, such as brain anatomy which determines current field distribution and may thus significantly impact stimulation effects. Computational modeling approaches may significantly advance our understanding of such factors, but the association of simulation-based tDCS-induced fields and neurophysiological outcomes has not been investigated.
Somatosensory and transcranial direct current stimulation effects on manual dexterity and motor cortex function: A metaplasticity studyNon-invasive neuromodulation may provide treatment strategies for neurological deficits affecting movement, such as stroke. For example, weak electrical stimulation applied to the hand by wearing a “mesh glove” (MGS) can transiently increase primary motor cortex (M1) excitability. Conversely, transcranial direct current stimulation with the cathode over M1 (c-tDCS) can decrease corticomotor excitability. Objective/Hypothesis: We applied M1 c-tDCS as a priming adjuvant to MGS and hypothesised metaplastic effects would be apparent in improved motor performance and modulation of M1 inhibitory and facilitatory circuits.
Motor training modulates intracortical inhibitory dynamics in motor cortex during movement preparationThe primary motor cortex (M1) has a vital role to play in the learning of novel motor skills. However, the physiological changes underpinning this learning, particularly in terms of dynamic changes during movement preparation, are incompletely understood. In particular, a substantial decrease in resting gamma-amino butyric acid (GABA) activity, i.e. a release of resting inhibition, is seen within M1 as a subject prepares to move. Although there is evidence that a decrease in resting inhibition occurs within M1 during motor learning it is not known whether the pre-movement “release” of GABAergic inhibition is modulated during skill acquisition.
Cortical inhibitory and excitatory function in drug-naive generalized anxiety disorderA growing body of evidence suggests that deficits in GABAergic inhibitory and glutamatergic excitatory neurotransmission may be involved in the core pathophysiology of generalized anxiety disorder (GAD), a disease characterized by pathological anxious worrying. The aim of the present study was to measure motor cortical excitability by paired-pulse transcranial magnetic stimulation (ppTMS) in patients with GAD.
Effects of Concomitant Stimulation of the GABAergic and Norepinephrine System on Inhibitory Control – A Study Using Transcutaneous Vagus Nerve StimulationInhibitory control processes are a central executive function allowing to control one's attention, behavior, and thoughts by overriding a strong internal predisposition or external lure [1,2]. Yet, other executive control subprocesses may interfere with the processes in most daily life situations. Working memory processes have been shown to modulate response inhibition processes, with high working memory load impairing response inhibition [3–5]. However, response inhibition functions can also work as subprocesses supporting executive control functions.
The Homeostatic Interaction Between Anodal Transcranial Direct Current Stimulation and Motor Learning in Humans is Related to GABAA ActivityThe relative timing of plasticity-induction protocols is known to be crucial. For example, anodal transcranial direct current stimulation (tDCS), which increases cortical excitability and typically enhances plasticity, can impair performance if it is applied before a motor learning task. Such timing-dependent effects have been ascribed to homeostatic plasticity, but the specific synaptic site of this interaction remains unknown.
Neurochemical Modulation in Posteromedial Default-mode Network Cortex Induced by Transcranial Magnetic StimulationThe Default Mode Network (DMN) is severely compromised in several psychiatric and neurodegenerative disorders where plasticity alterations are observed. Glutamate and GABA are the major excitatory and inhibitory brain neurotransmitters respectively and are strongly related to plasticity responses and large-scale network expression.
Cortical Reorganization Due to Impaired Cerebral Autoregulation in Individuals With Occlusive Processes of the Internal Carotid ArteryTo study the impact of impaired cerebral autoregulation on cortical neurophysiology, long term potentiation (LTP)-like plasticity, motor learning and brain structure.