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Til Ole Bergmann

Til Ole Bergmann
Germany Resilience Center (Deutsches Resilienz Zentrum DRZ) Mainz · Research Group Neurostimulation

PhD

About

80
Publications
17,189
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3,870
Citations
Additional affiliations
October 2015 - present
University of Tuebingen
Position
  • PostDoc Position
January 2014 - September 2015
Christian-Albrechts-Universität zu Kiel
Position
  • PostDoc Position
March 2011 - December 2013
Radboud University
Position
  • PostDoc Position

Publications

Publications (80)
Article
In this issue of Neuron, Helfrich et al. (2017) demonstrate that phase-amplitude coupling (PAC) between slow oscillations and spindles is crucial for memory consolidation, and shifts in its phase relationship may explain age-related deficits in memory performance. These results also suggest a more general function of PAC in synaptic plasticity.
Article
Full-text available
Non-invasive transcranial brain stimulation (NTBS) techniques such as transcranial magnetic stimulation (TMS) and transcranial current stimulation (TCS) are important tools in human systems and cognitive neuroscience because they are able to reveal the relevance of certain brain structures or neuronal activity patterns for a given brain function. I...
Article
Full-text available
Cortical oscillations, such as 8–12 Hz alpha-band activity, are thought to subserve gating of information processing in the human brain. While most of the supporting evidence is correlational, causal evidence comes from attempts to externally drive (“entrain”) these oscillations by transcranial magnetic stimulation (TMS). Indeed, the frequency prof...
Article
Full-text available
During systems-level consolidation, mnemonic representations initially reliant on the hippocampus are thought to migrate to neocortical sites for more permanent storage, with an eminent role of sleep for facilitating this information transfer. Mechanistically, consolidation processes have been hypothesized to rely on systematic interactions between...
Article
Full-text available
Evoked cortical responses do not follow a rigid input-output function but are dynamically shaped by intrinsic neural properties at the time of stimulation. Recent research has emphasized the role of oscillatory activity in determining cortical excitability. Here we employed EEG-guided transcranial magnetic stimulation (TMS) during non-rapid eye mov...
Preprint
Full-text available
One of the most critical challenges in using non-invasive brain stimulation (NIBS) techniques for the treatment of psychiatric and neurologic disorders is inter- and intra-individual variability in response to NIBS. Response variations in previous findings suggest that the one-size-fits-all approach does not seem the most appropriate option for enh...
Article
Full-text available
Low-intensity transcranial electrical stimulation (tES), including alternating or direct current stimulation, applies weak electrical stimulation to modulate the activity of brain circuits. Integration of tES with concurrent functional MRI (fMRI) allows for the mapping of neural activity during neuromodulation, supporting causal studies of both bra...
Article
The slow wave state is a general state of quiescence interrupted by sudden bursts of activity or so-called slow wave events (SWEs). Recently, the relationship between SWEs and blood oxygen level–dependent (BOLD) functional magnetic resonance imaging (fMRI) signals was assessed in rodent models which revealed cortex-wide BOLD activation. However, it...
Article
Transcranial ultrasound stimulation (TUS) holds great potential as a tool to alter neural circuits non-invasively in both animals and humans. In contrast to established non-invasive brain stimulation methods, ultrasonic waves can be focused on both cortical and deep brain targets with the unprecedented spatial resolution as small as a few cubic mil...
Article
Full-text available
Non-invasive brain stimulation (NIBS) experiments involve many recurring procedures that are not sufficiently standardized in the community. Given the diversity in experimental design and experience of the investigators, automated but yet flexible data collection and analysis tools are needed to increase objectivity, reliability, and reproducibilit...
Article
Understanding the neural correlates of risk-sensitive skin conductance responses can provide insights into their connection to emotional and cognitive processes. To provide insights into this connection, we studied the cortical correlates of risk-sensitive skin conductance peaks using electroencephalography. Fluctuations in skin conductance respons...
Article
The experimental manipulation of neural activity by neurostimulation techniques overcomes the inherent limitations of correlative recordings, enabling the researcher to investigate causal brain-behavior relationships. But only when stimulation and recordings are combined, the direct impact of the stimulation on neural activity can be evaluated. In...
Article
Background: Sleep consolidates declarative memory by repeated replay linked to the cardinal oscillations of non-rapid eye movement (NonREM) sleep. However, there is so far little evidence of classical glutamatergic plasticity induced by this replay. Rather, we have previously reported that blocking N-methyl-D-aspartate (NMDA) or α-amino-3-hydroxy-...
Article
Full-text available
The perturbational complexity index (PCI) measures the spatiotemporal dynamics of transcranial magnetic stimulation (TMS)-evoked electroencephalography (EEG) potentials (TEPs). High PCI values reflect the joint presence of integration and differentiation in thalamocortical networks of conscious brains. Low PCI values have been reported during natur...
Preprint
Full-text available
Recent studies suggest that transcranial electrical stimulation (tES) can be performed during functional magnetic resonance imaging (fMRI). The novel approach of using concurrent tES-fMRI to modulate and measure targeted brain activity/connectivity may provide unique insights into the causal interactions between the brain neural responses and psych...
Preprint
Full-text available
Background Low intensity transcranial electrical stimulation (tES), including alternating or direct current stimulation (tACS or tDCS), applies weak electrical stimulation to modulate brain circuits. Integration of tES with concurrent functional magnetic resonance imaging (fMRI) allows neuromodulation of brain regions while mapping network function...
Preprint
Full-text available
Background Sleep consolidates declarative memory by repeated replay linked to the cardinal oscillations of NonREM sleep. However, there is so far little evidence of classical glutamatergic plasticity induced by this replay. Rather, we have previously reported that blocking NMDA or AMPA receptors does not affect sleep-dependent consolidation of decl...
Article
Full-text available
Noninvasive brain stimulation (NIBS) techniques, such as transcranial magnetic stimulation or transcranial direct and alternating current stimulation, are advocated as measures to enable causal inference in cognitive neuroscience experiments. Transcending the limitations of purely correlative neuroimaging measures and experimental sensory stimulati...
Article
Full-text available
Alpha oscillations (8-14 Hz) are assumed to gate information flow in the brain by means of pulsed inhibition, i.e., the phasic suppression of cortical excitability and information processing once per alpha cycle, resulting in stronger net suppression for larger alpha amplitudes due to the assumed amplitude asymmetry of the oscillation. While there...
Article
Full-text available
Frequency tagging has been widely used to study the role of visual selective attention. Presenting a visual stimulus flickering at a specific frequency generates so-called steady-state visually evoked responses. However, frequency tagging is mostly done at lower frequencies (<30 Hz). This produces a visible flicker, potentially interfering with bot...
Article
Full-text available
Ongoing brain activity has been implicated in the modulation of cortical excitability. The combination of electroencephalography (EEG) and transcranial magnetic stimulation (TMS) in a real-time triggered setup is a novel method for testing hypotheses about the relationship between spontaneous neuronal oscillations, cortical excitability, and synapt...
Article
Brain responses to transcranial magnetic stimulation (TMS) recorded by electroencephalography (EEG) are emergent noninvasive markers of neuronal excitability and effective connectivity in humans. However, the underlying physiology of these TMS‐evoked EEG potentials (TEPs) is still heavily underexplored, impeding a broad application of TEPs to study...
Article
Full-text available
Transcranial Magnetic Stimulation (TMS) excites populations of neurons in the stimulated cortex, and the resulting activation may spread to connected brain regions. The distributed cortical response can be recorded with electroencephalography (EEG). Since TMS also stimulates peripheral sensory and motor axons and generates a loud "click" sound, the...
Preprint
Full-text available
Ongoing brain activity has been implicated in the modulation of cortical excitability. The combination of electroencephalography (EEG) and transcranial magnetic stimulation (TMS) in a real-time triggered setup is a novel method for testing hypotheses about the relationship between spontaneous neuronal oscillations, cortical excitability, and synapt...
Article
Low frequency oscillations such as alpha (8-12 Hz) are hypothesized to rhythmically gate sensory processing, reflected by 40-100 Hz gamma band activity, via the mechanism of pulsed inhibition. We applied transcranial alternating current stimulation (TACS) at individual alpha frequency (IAF) and flanking frequencies (IAF-4 Hz, IAF+4 Hz) to the occip...
Preprint
Full-text available
Transcranial Magnetic Stimulation (TMS) excites populations of neurons in the stimulated cortex, and the resulting activation may spread to connected brain regions. The distributed cortical response can be recorded with electroencephalography (EEG). Since TMS also stimulates peripheral sensory and motor axons and generates a loud click sound, the T...
Article
Background: Alpha (8-14 Hz) oscillatory power is linked to cortical excitability and corresponding modulations of sensory evoked potentials and perceptual detection performance. In somatosensory cortex (S1), negative linear and inverted U-shape relationships exist, whereas its effect on the primary motor cortex (M1) is hardly known. Objective: W...
Preprint
Full-text available
The capacity to externally control transcranial magnetic stimulation (TMS) devices is becoming increasingly important in brain stimulation research. Here we introduce MAGIC (MAGnetic stimulator Interface Controller), an open-source MATLAB toolbox for controlling Magstim and MagVenture stimulators. MAGIC includes a series of MATLAB functions which a...
Article
Introduction Focal transcranial magnetic stimulation (TMS) induces somatosensory input due to excitation of peripheral trigeminal nerve branches as well as auditory input caused by the loud click produced during stimulus discharge. In a recent study, we have demonstrated that these peripheral sources of cortical activation make a strong contributio...
Preprint
Full-text available
Alpha oscillations (8-12 Hz) are hypothesized to rhythmically gate sensory processing, reflected by activity in the 40-100 Hz gamma band, via the mechanism of pulsed inhibition. We applied transcranial alternating current stimulation (TACS) at individual alpha frequency (IAF) and flanking frequencies (IAF-4 Hz, IAF+4 Hz) to the occipital cortex of...
Article
According to the influential “pulsed inhibition hypothesis” (Jensen and Mazaheri, FHN 2010), the 8–14 Hz alpha oscillation, termed μ-rhythm in the sensorimotor cortex, is driven by bouts of inhibition (or deflections of the cortical excitation-inhibition balance towards inhibition), rhythmically suppressing neural processing during the inhibitory p...
Article
Objectives Transcranial Magnetic Stimulation (TMS) is capable to non-invasively stimulate the human cortex. Electroencephalography (EEG) can record the cortical response evoked by TMS (TEPs), which are a summation of the brain responses to the TMS-induced electric field in the cortex, and to the multisensory peripheral stimulation derived from the...
Article
Brain responses to transcranial magnetic stimulation (TMS) as measured with electroencephalography (EEG) have so far been assessed either by TMS-evoked EEG potentials (TEPs), mostly reflecting phase-locked neuronal activity, or time-frequency-representations (TFRs), reflecting oscillatory power arising from a mixture of both evoked (i.e., phase-loc...
Article
Introduction Alpha oscillations (8–12 Hz) are proposed to mediate ‘attentional gating’ by suppressing neuronal processing in task-irrelevant sensory regions, reflected by ‘pulsed-inhibition’ of stimulus-induced gamma-band activity (40–100 Hz). Concurrent TACS-MEG has the potential to reveal TACS entrainment of alpha oscillations at the stimulation...
Conference Paper
Transcranial Magnetic Stimulation (TMS) can effectively stimulate non-invasively the human cortex. The TMS-evoked cortical response can be recorded with electroencephalography (EEG). However, TMS also stimulates our senses by stimulating peripheral trigeminal nerve fibers and creating a loud click. This implies that the TMS-evoked EEG response not...
Chapter
Newly acquired memories are initially hippocampus-dependent and need to undergo a process of active system consolidation, during which they are redistributed to neocortical sites for long-term storage. This process is thought to take place during phases of quiet wakefulness and non-rapid-eye movement (NREM) sleep and is presumably based on the repe...
Article
Non-invasive transcranial brain stimulation (NTBS) techniques have a wide range of applications but also suffer from a number of limitations mainly related to poor specificity of intervention and variable effect size. These limitations motivated recent efforts to focus on the temporal dimension of NTBS with respect to the ongoing brain activity. Te...
Article
Full-text available
Background: Instrumental action is well known to be vulnerable to affective value. Excessive transfer of affective value to instrumental action is thought to contribute to psychiatric disorders. The brain region most commonly implicated in overriding such affective biasing of instrumental action is the prefrontal cortex. Objective: The aim of th...
Article
Background: In attention-deficit/hyperactivity disorder (ADHD) not only deficits in dopamine-related cognitive functioning have been found but also a lower dopamine-sensitive olfactory threshold. The aim of the present study was to proof that only olfactory but not trigeminal sensitivity is increased in ADHD. Structural magnetic resonance imaging...
Article
Neuronal oscillations in the alpha band (8 - 12Hz) in visual cortex are considered to instantiate 'attentional gating' via the inhibition of activity in regions representing task-irrelevant parts of space. In contrast, visual gamma-band activity (40 - 100Hz) is regarded as representing a bottom-up drive from incoming visual information, with increa...
Article
Full-text available
Author Summary Directing attention to a part of visual space produces patterns of "brainwaves" or neuronal oscillations in the human visual cortex (the part of the brain at the back that processes incoming information from the eyes); oscillations at low frequencies are believed to help the brain block out irrelevant or distracting information, wher...
Article
Non-invasive transcranial brain stimulation (NTBS) is widely used to elucidate the contribution of different brain regions to various cognitive functions. Here we present three modeling approaches that are informed by functional or structural brain mapping or behavior profiling and discuss how these approaches advance the scientific potential of NT...
Article
Full-text available
Stroke is the leading cause of disability in the United States. Despite the high incidence and mortality of stroke, sensitive and specific brain-based biomarkers predicting persisting disabilities are lacking. Both neuroimaging techniques like electroencephalography (EEG) and non-invasive brain stimulation (NIBS) techniques such as transcranial mag...
Article
Full-text available
Covertly directing visuospatial attention produces a frequency-specific modulation of neuronal oscillations in occipital and parietal cortices: anticipatory alpha (8-12 Hz) power decreases contralateral and increases ipsilateral to attention, whereas stimulus-induced gamma (>40 Hz) power is boosted contralaterally and attenuated ipsilaterally. Thes...
Article
Full-text available
Sensory systems must rely on powerful mechanisms for organizing complex information. We propose a framework in which inhibitory alpha oscillations limit and prioritize neuronal processing. At oscillatory peaks, inhibition prevents neuronal firing. As the inhibition ramps down within a cycle, a set of neuronal representations will activate sequentia...
Article
Introduction Alpha oscillations in visual cortex serve as a mechanism of attentional enhancement via inhibition of task-irrelevant brain regions (Jensen et al., TICS 2012). Humans are able to direct their attention to one visual hemifield in response to an endogenous cue via the modulation of alpha power in visual areas. This top-down control of sp...
Article
Entsprechend dem Konzept der Fötalen Programmierung wirkt sich pränataler Stress nachhaltig auf die Gesundheit des Nachkömmlings aus. Die Hypothalamus-Hypophysen-Nebennierenrinden-Achse wird als eine mediierende Struktur angenommen, über welche sich mütterlicher Stress in der intrauterinen Umwelt auf den Fötus auswirkt. In der vorliegenden Studie w...
Article
Introduction Simultaneous transcranial magnetic stimulation (TMS) and electroencephalography (EEG) allows the direct assessment of cortico-thalamic responsiveness by TMS-evoked EEG potentials (TEPs). Notably, the frequency composition of TEPs corresponds to the dominant spontaneous oscillation at the respective stimulation site, e.g. ′alpha′ in the...
Article
Full-text available
Repetitive transcranial magnetic stimulation (rTMS) of the human motor hand area (M1) can induce lasting changes in corticospinal excitability as indexed by a change in amplitude of the motor-evoked potential. The plasticity-inducing effects of rTMS in M1 show substantial inter-individual variability which has been partially attributed to the valme...
Article
Newly acquired declarative memory traces are believed to be reactivated during NonREM sleep to promote their hippocampo-neocortical transfer for long-term storage. Yet it remains a major challenge to unravel the underlying neuronal mechanisms. Using simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) recording...
Article
Full-text available
Thalamo-cortical spindles driven by the up-state of neocortical slow (< 1 Hz) oscillations (SOs) represent a candidate mechanism of memory consolidation during sleep. We examined interactions between SOs and spindles in human slow wave sleep, focusing on the presumed existence of 2 kinds of spindles, i.e., slow frontocortical and fast centro-pariet...
Article
Previous studies have shown that the efficacy of transcranial magnetic stimulation (TMS) to excite corticospinal neurons depends on pulse waveform. OBJECTIVE/HYPOTHESES: In this study, we examined whether the effectiveness of polyphasic TMS can be increased by using a pulse profile that consists of multiple sine cycles. In eight subjects, single-pu...
Article
Full-text available
Background: Associative high-frequency electrical stimulation (HFS) of the supraorbital nerve in five healthy individuals induced long-term potentiation (LTP)-like or depression (LTD)-like changes in the human blink reflex circuit according to the rules of spike timing-dependent plasticity (Mao and Evinger, 2001). HFS given at the onset of the R2...
Article
Constant transcranial direct stimulation (c-tDCS) of the primary motor hand area (M1(HAND)) can induce bidirectional shifts in motor cortical excitability depending on the polarity of tDCS. Recently, anodal slow oscillation stimulation at a frequency of 0.75 Hz has been shown to augment intrinsic slow oscillations during sleep and theta oscillation...