Background: The principle of gain control determines the efficiency of neuronal processing and can be enhanced with pharmacological or brain stimulation methods. It is a key factor for cognitive control, but the degree of how much gain control may be enhanced underlies a physical limit.
Methods: To investigate whether methylphenidate (MPH) and transcranial direct current stimulation (tDCS) share common underlying mechanisms and cognitive effects, we administered MPH and anodal tDCS (atDCS) over the right inferior frontal gyrus both separately and combined, while healthy adult participants (n = 104) performed a response selection and inhibition task.
Catecholamines and amino acid transmitter systems are known to interact, the exact links and their impact on cognitive control functions have however remained unclear. Using a multi-modal imaging approach combining EEG and proton-magnetic resonance spectroscopy (H-MRS), we investigated the effect of different degrees of pharmacological catecholaminergic enhancement onto theta band activity (TBA) as a measure of interference control during response inhibition and execution. It was central to our study to evaluate the predictive impact of in-vivo baseline GABA+ concentrations in the striatum, the anterior cingulate cortex (ACC) and the supplemental motor area (SMA) of healthy adults under varying degrees of methylphenidate (MPH) stimulation.
View Article and Find Full Text PDFIn recent years, there has been many efforts to establish a comprehensive theoretical framework explaining the working mechanisms involved in perception-action integration. This framework stresses the importance of the immediate past on mechanisms supporting perception-action integration. The present study investigates the neurophysiological principles of dynamic perception-action bindings, particularly considering the influence of the immediate history on action control mechanisms.
View Article and Find Full Text PDFIndividuals organize the evolving stream of events in their environment by partitioning it into discrete units. Event segmentation theory (EST) provides a cognitive explanation for the process of this partitioning. Critically, the underlying time-resolved neural mechanisms are not understood, and thus a central conceptual aspect of how humans implement this central ability is missing.
View Article and Find Full Text PDFResponse inhibition is an important instance of cognitive control and can be complicated by perceptual conflict. The neurophysiological mechanisms underlying these processes are still not understood. Especially the relationship between neural processes directly preceding cognitive control (proactive control) and processes underlying cognitive control (reactive control) has not been examined although there should be close links.
View Article and Find Full Text PDFGoal-directed behavior requires integrated mental representations of perceptions and actions. The neurophysiological underpinnings of these processes, however, are not yet understood. It is particularly undetermined, which oscillatory activities in which brain regions are involved in the management of perception-action representations.
View Article and Find Full Text PDFGilles de la Tourette syndrome (GTS) is a neuropsychiatric disorder. Because motor signs are the defining feature of GTS, addressing the neurophysiology of motor processes is central to understanding GTS. The integration of voluntary motor processes is subject to so-called "binding problems", i.
View Article and Find Full Text PDFCognitive flexibility is an essential facet of everyday life, for example, when switching between different tasks. Neurophysiological accounts on cognitive flexibility have often focused on the task switch itself, disregarding preceding processes and the possible impact of "brain states" before engaging in cognitive flexibility. In a combined working memory/task-switching paradigm, we examined how neuronal processes during cognitive flexibility are interrelated to preceding neuronal processes across time and brain regions in a sample of n = 42 healthy adults.
View Article and Find Full Text PDFHigh-dose alcohol intoxication reduces cognitive control, including inhibition. Although inhibition deficits may contribute to the behavioral deficits commonly observed in alcohol use disorder (AUD), many questions about potentially modulating factors have remained unanswered. We examined the effects of experimentally induced high-dose alcohol intoxication (~ 1.
View Article and Find Full Text PDFThe occurrence of motor/vocal tics, that is, "extra movements" and/or "extra vocalizations," is the leading diagnostic criterion for tic disorders. We show that extra movements are common also in healthy controls, so that a surplus of movements per se is not indicative of the presence of a tic disorder. This questions the usefulness of Diagnostic and Statistical Manual of Mental Disorders, 5th edition criteria for tic disorders in clinical practice.
View Article and Find Full Text PDFEven simple actions like opening a door require integration/binding and flexible reactivation of different motor elements. Yet, the neural mechanisms underlying the processing of such "embedded response plans" are largely elusive, despite theoretical frameworks, such as the theory of event coding, describing the involved cognitive processes. In a sample of = 40 healthy participants, we combine time-frequency decomposition and various beamforming methods to examine the neurophysiological dynamics of such action plans, with special emphasis on the interplay of theta and beta frequency activity during the processing of these plans.
View Article and Find Full Text PDFInhibition of inappropriate behavior is relevant in many everyday situations. Nevertheless, the mechanisms that induce response inhibition based on sensory information and what influences these mechanisms are not entirely understood. We examined neurophysiological processes of perception-action integration in response inhibition and the impact of the pre-trial neurophysiological functional connectivity state in the theta and alpha band on these integration processes.
View Article and Find Full Text PDFThe ability to inhibit a prepotent response is a crucial prerequisite of goal-directed behavior. So far, research on response inhibition has mainly examined these processes when there is little to no cognitive control during the decision to respond. We manipulated the "context" in which response inhibition has to be exerted (i.
View Article and Find Full Text PDF