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The evaluation of transcranial magnetic stimulation (TMS)-induced motor evoked potentials (MEPs) promises valuable information about fundamental brain related mechanisms and may serve as a diagnostic tool for clinical monitoring of therapeutic progress or surgery procedures. However, reports about spontaneous fluctuations of MEP amplitudes causing high intra-individual variability have led to increased concerns about the reliability of this measure. One possible cause for high variability of MEPs could be neuronal oscillatory activity, which reflects fluctuations of membrane potentials that systematically increase and decrease the excitability of neuronal networks. Here, we investigate the dependence of MEP amplitude on oscillation power and phase by combining the application of single pulse TMS over the primary motor cortex with concurrent recordings of electromyography and electroencephalography. Our results show that MEP amplitude is correlated to alpha phase, alpha power as well as beta phase. These findings may help explain corticospinal excitability fluctuations by highlighting the modulatory effect of alpha and beta phase on MEPs. In the future, controlling for such a causal relationship may allow for the development of new protocols, improve this method as a (diagnostic) tool and increase the specificity and efficacy of general TMS applications.

BackgroundMost of our decisions involve a certain degree of risk regarding the outcomes of our choices. People vary in the way they make decisions, resulting in different levels of risk-taking behavior. These differences have been linked to prefrontal theta band activity. However, a direct functional relationship between prefrontal theta band activity and risk-taking has not yet been demonstrated.ObjectiveWe used noninvasive brain stimulation to test the functional relevance of prefrontal oscillatory theta activity for the regulatory control of risk-taking behavior.MethodsIn a within-subject experiment, 31 healthy participants received theta (6.5 Hertz [Hz]), gamma (40 Hz), and sham transcranial alternating current stimulation (tACS) over the left prefrontal cortex (lPFC). During stimulation, participants completed a task assessing their risk-taking behavior as well as response times and sensitivity to value and outcome probabilities. Electroencephalography (EEG) was recorded before and immediately after stimulation to investigate possible long-lasting stimulation effects.ResultsTheta band, but not gamma band or sham, tACS led to a significant reduction in risk-taking behavior, indicating a frequency-specific effect of prefrontal brain stimulation on the modulation of risk-taking behavior. Moreover, theta band stimulation led to increased response times and decreased sensitivity to reward values. EEG data analyses did not show an offline increase in power in the stimulated frequencies after the stimulation protocol.ConclusionThese findings provide direct empirical evidence for the effects of prefrontal theta band stimulation on behavioral risk-taking regulation.

BackgroundVoluntary shifts of visuospatial attention are associated with a lateralization of occipitoparietal alpha power (7-13Hz), i.e. higher power in the hemisphere ipsilateral and lower power contralateral to the locus of attention. Recent noninvasive neuromodulation studies demonstrated that alpha power can be experimentally increased using transcranial alternating current stimulation (tACS).Objective/HypothesisWe hypothesized that tACS at alpha frequency over the left parietal cortex induces shifts of attention to the left hemifield. However, spatial attention shifts not only occur voluntarily (endogenous), but also stimulus-driven (exogenous). In order to study the task-specificity of the potential effects of tACS on attentional processes, we administered three conceptually different spatial attention tasks.Methods36 healthy volunteers were recruited from an academic environment. In two seperate sessions, we applied either high-density tACS at 10Hz, or sham tACS, for 35-40 minutes to their left parietal cortex. We systematically compared performance on endogenous attention, exogenous attention, and stimulus detection tasks.ResultsIn the Endogenous attention task, we found a greater leftward bias in reaction times during left parietal 10Hz tACS as compared to sham. There were no stimulation effects in the exogenous attention or stimulus detection task.ConclusionThe study shows that high-density tACS at 10Hz can be used to modulate visuospatial attention performance. The tACS effect is task-specific, indicating that not all forms of attention are equally susceptible to the stimulation.

This study aimed at examining cognitive predictors of reactive and proactive aggression in a forensic-psychiatric (n = 80) and a non-clinical sample (n = 98; Brugman et al., 2015). Three different cognitive predictors were incorporated: (1) attentional bias towards aggressive stimuli (measured with Emotional Stroop task) and towards angry faces (measured with a visual search task); (2) interpretation biases (measured with Aggressive Interpretative Bias Task (AIBT) and a vignette task), and (3) implicit self-aggression association (measured with a Single-Target Implicit Association Task). To measure aggression, the Reactive-Proactive Aggression Questionnaire (RPQ) and the Taylor Aggression Paradigm (TAP) were used. An automatic self-aggression association positively predicted proactive aggressive behavior on the TAP in both samples. Furthermore, this self-aggression association predicted, increased self-reported proactive aggression (RPQ) in the forensic sample only. Pain, injury, and danger interpretations reported on the vignettes, negatively predicted self-reported proactive aggression in both samples. A stronger aggressive interpretation bias on the AIBT predicted more reactive aggressive behavior (TAP) in the non-clinical sample only. Taken together, findings show both common and distinct mechanisms in reactively vs. proactively driven aggressive behavior.

The concept of interhemispheric competition has been very influential in attention research, and the occurrence of biased attention due to an imbalance in posterior parietal cortex (PPC) is well documented. In this context, the vast majority of studies have assessed attentional performance with tasks that did not include an explicit experimental manipulation of attention, and, as a consequence, it remains largely unknown how these findings relate to core attentional constructs such as endogenous and exogenous control and spatial orienting and reorienting. We here addressed this open question by creating an imbalance between left and right PPC with transcranial direct current stimulation, resulting in right-hemispheric dominance, and assessed performance on three experimental paradigms that isolate distinct attentional processes. The comparison between active and sham transcranial direct current stimulations revealed a highly informative pattern of results with differential effects across tasks. Our results demonstrate the functional necessity of PPC for endogenous and exogenous attentional control and, importantly, link the concept of interhemispheric competition to core attentional processes, thus moving beyond the notion of biased attention after noninvasive brain stimulation over PPC.

We combined patterned TMS with EMG in several sessions of a within-subject design to assess and characterize intraindividual reliability and interindividual variability of TMS-induced neuroplasticity mechanisms in the healthy brain. Intermittent theta burst stimulation (iTBS) was applied over M1 to induce long-term potentiation-like mechanisms as assessed by changes in corticospinal excitability. Furthermore, we investigated the association between the observed iTBS effects and individual differences in prolonged measures of corticospinal excitability. Our results show that iTBS-induced measures of neuroplasticity suffer from high variability between individuals within a single assessment visit and from low reliability within individuals across two assessment visits. This indicates that both group and individual effects of iTBS on corticospinal excitability cannot be assumed to be reliable and therefore need to be interpreted with caution, at least when measured by changes in the amplitudes of motor-evoked potentials.

The successful inhibition of sexual thoughts, desires, and behaviors represents an essential ability for adequate functioning in our daily life. Evidence derived from lesion studies indicates a link between sexual inhibition and the general ability for behavioral and cognitive control. This is further supported by the high comorbidity of sexual compulsivity with other inhibition-related disorders. Here, we aimed at investigating whether sexual and general inhibition recruit overlapping or distinct neural correlates in the brain. Furthermore, we investigated the specificity of two different kinds of sexual inhibition: inhibition of sexually driven motor responses and inhibition of sexual incoming information. To this end, 22 healthy participants underwent functional Magnetic Resonance Imaging (fMRI) while performing a task requiring general response inhibition (Go/No-go), as well as cognitive and motivational sexual inhibition (Negative Affective Priming and Approach-Avoidance task). Our within-subject within-session design enabled the direct statistical comparison between general and sexual inhibitory mechanisms. The general inhibition task recruited mainly prefrontal and insular regions, replicating previous findings. In contrast, the two types of sexual inhibition activated both common and distinct neural networks. Whereas cognitive sexual inhibition engaged the inferior frontal gyrus, the orbitofrontal cortex and the fusiform gyrus, motivational sexual inhibition was characterized by a hypoactivation in the anterolateral prefrontal cortex. Both types of sexual inhibition recruited the inferior frontal gyrus and the inferotemporal cortex. However, the activity of the inferior frontal gyrus did not correlate with behavioral inhibitory scores. These results support the hypothesis of inhibitory processing being an emergent property of a functional network.

The assessment of corticospinal excitability by means of transcranial magnetic stimulation-induced motor evoked potentials is an established diagnostic tool in neurophysiology and a widely used procedure in fundamental brain research. However, concern about low reliability of these measures has grown recently. One possible cause of high variability of MEPs under identical acquisition conditions could be the influence of oscillatory neuronal activity on corticospinal excitability. Based on research showing that transcranial alternating current stimulation can entrain neuronal oscillations we here test whether alpha or beta frequency tACS can influence corticospinal excitability in a phase-dependent manner. We applied tACS at individually calibrated alpha- and beta-band oscillation frequencies, or we applied sham tACS. Simultaneous single TMS pulses time locked to eight equidistant phases of the ongoing tACS signal evoked MEPs. To evaluate offline effects of stimulation frequency, MEP amplitudes were measured before and after tACS. To evaluate whether tACS influences MEP amplitude, we fitted one-cycle sinusoids to the average MEPs elicited at the different phase conditions of each tACS frequency. We found no frequency-specific offline effects of tACS. However, beta-frequency tACS modulation of MEPs was phase-dependent. Post hoc analyses suggested that this effect was specific to participants with low (

The insular cortex has consistently been associated with various aspects of emotion regulation and social interaction, including anger processing and overt aggression. Aggression research distinguishes proactive or instrumental aggression from retaliation, i.e. aggression in response to provocation. Here, we investigated the specific role of the insular cortex during retaliation, employing a controlled behavioral aggression paradigm implementing different levels of provocation. Fifteen healthy male volunteers underwent whole brain functional magnetic resonance imaging (fMRI) to identify brain regions involved in interaction with either a provoking or a non-provoking opponent. FMRI group analyses were complemented by examining the parametric modulations of brain activity related to the individual level of displayed aggression. These analyses identified a hemispheric lateralization as well as an anatomical segregation of insular cortex with specifically the left posterior part being involved in retaliation. The left-lateralization of insular activity during retaliation is in accordance with evidence from electro-physiological studies, suggesting left-lateralized fronto-cortical dominance during anger processing and aggressive acts. The posterior localization of insular activity, on the other hand, suggests a spatial segregation within insular cortex with particularly the posterior part being involved in the processing of emotions that trigger intense bodily sensations and immediate action tendencies.

Aggressive behavior poses a threat to human collaboration and social safety. It is of utmost importance to identify the functional mechanisms underlying aggression and to develop potential interventions capable of reducing dysfunctional aggressive behavior already at a brain level. We here experimentally shifted fronto-cortical asymmetry to manipulate the underlying motivational emotional states in both male and female participants while assessing the behavioral effects on proactive and reactive aggression. Thirty-two healthy volunteers received either anodal transcranial direct current stimulation to increase neural activity within right dorsolateral prefrontal cortex, or sham stimulation. Aggressive behavior was measured with the Taylor Aggression Paradigm (TAP). We revealed a general gender effect, showing that males displayed more behavioral aggression than females. After the induction of right fronto-hemispheric dominance, proactive aggression was reduced in males. The current study demonstrates that non-invasive brain stimulation can reduce aggression in males. This is a relevant and promising step to better understand how cortical brain states connect to impulsive actions and to examine the causal role of the prefrontal cortex in aggression. Ultimately such findings could help to examine whether the brain can be a direct target for potential supportive interventions in clinical settings dealing with overly aggressive patients and/or violent offenders.

Social norms, such as treating others fairly regardless of kin relations, are essential for the functioning of human societies. Their existence may explain why humans, among all species, show unique patterns of pro-social behaviour (Sethi and Somanathan, 1996; Gintis, 2000; Ostrom, 2000; Fehr and Fischbacher, 2003; Gintis, 2003). The maintenance of social norms often depends on external enforcement, as in the absence of credible sanctioning mechanisms pro-social behaviour deteriorates quickly (Fehr and Gachter, 2000; Fehr and Fischbacher, 2004). This sanction-dependent pro-social behaviour suggests that humans strategically adapt their behaviour and act selfishly if possible but control selfish impulses if necessary. Recent studies point at the role of the dorsolateral prefrontal cortex (DLPFC) in controlling selfish impulses (Wout et al., 2005; Knoch et al., 2006; Knoch et al., 2009; Ruff et al., 2013). We test, whether the DLPFC is indeed involved in the control of selfish impulses as well as the strategic acquisition of this control mechanism. Using repetitive transcranial magnetic stimulation, we provide evidence for the causal role of the right DLPFC in strategic fairness. Since the DLPFC is phylogenetically one of the latest developed neocortical regions (Fuster, 2001) this could explain why complex norm systems exist in humans but not in other social animals.data source: lab experiment data, available from authors upon request

Cognitive effort and self-control are exhausting. Although evidence is ambiguous, behavioural studies have repeatedly suggested that control-demanding tasks seem to deplete a limited cache of self-regulatory resources leading to performance degradations and fatigue. While resource depletion has indirectly been associated with a decline in right prefrontal cortex capacity, its precise neural underpinnings have not yet been revealed. This study consisted of two independent experiments, which set out to investigate the causal role of the right dorsolateral prefrontal cortex (DLPFC) in a classic dual phase depletion paradigm employing non-invasive brain stimulation. In Experiment 1 we demonstrated a general depletion effect, which was significantly eliminated by anodal transcranial Direct Current Stimulation to the right DLPFC. In Experiment 2, however, we failed to replicate the basic psychological depletion effect within a second independent sample. The dissimilar results are discussed in the context of the current 'replication crisis' and suggestions for future studies are offered. While our current results do not allow us to firmly argue for or against the existence of resource depletion, we outline why it is crucial to further clarify which specific external and internal circumstances lead to limited replicability of the described effect. We showcase and discuss the current inter-lab replication problem based on two independent samples tested within one research group (intra-lab).

The ability of inhibiting impulsive urges is paramount for human behavior. Such successful response inhibition has consistently been associated with activity in pFC. The current study aims to unravel the differential involvement of different areas within right pFC for successful action restraint versus action cancellation. These two conceptually different aspects of action inhibition were measured with a go/no-go task (action restraint) and a stop signal task (action cancellation). Localization of relevant prefrontal activation was based on fMRI data. Significant task-related activation during successful action restraint was localized for each participant individually in right anterior insula (rAI), right superior frontal gyrus, and pre-SMA. Activation during successful action cancellation was localized in rAI, right middle frontal gyrus, and pre-SMA. Subsequently, fMRI-guided continuous thetaburst stimulation was applied to these regions. Results showed that the disruption of neural activity in rAI reduced both the ability to restrain (go/no-go) and cancel (stop signal) responses. In contrast, continuous thetaburst stimulation-induced disruption of the right superior frontal gyrus specifically impaired the ability to restrain from responding (go/no-go), while leaving the ability for action cancellation largely intact. Stimulation applied to right middle frontal gyrus and pre-SMA did not affect inhibitory processing in neither of the two tasks. These findings provide a more comprehensive perspective on the role of pFC in inhibition and cognitive control. The results emphasize the role of inferior frontal regions for global inhibition, whereas superior frontal regions seem to be specifically relevant for successful action restraint.

Magnetoencephalography (MEG) has shown pseudohomophone priming effects at Broca's area (specifically pars opercularis of left inferior frontal gyrus and precentral gyrus; LIFGpo/PCG) within approximately 100ms of viewing a word. This is consistent with Broca's area involvement in fast phonological access during visual word recognition. Here we used online transcranial magnetic stimulation (TMS) to investigate whether LIFGpo/PCG is necessary for (not just correlated with) visual word recognition by approximately 100ms. Pulses were delivered to individually fMRI-defined LIFGpo/PCG in Dutch speakers 75-500ms after stimulus onset during reading and picture naming. Reading and picture naming reactions times were significantly slower following pulses at 225-300ms. Contrary to predictions, there was no disruption to reading for pulses before 225ms. This does not provide evidence in favour of a functional role for LIFGpo/PCG in reading before 225ms in this case, but does extend previous findings in picture stimuli to written Dutch words.

SummaryPeople suffering from developmental dyscalculia encounter difficulties in automatically accessing numerical magnitudes [1–3]. For example, when instructed to attend to the physical size of a number while ignoring its numerical value, dyscalculic subjects, unlike healthy participants, fail to process the irrelevant dimension automatically and subsequently show a smaller size-congruity effect (difference in reaction time between incongruent [e.g., a physically large 2 and a physically small 4] and congruent [e.g., a physically small 2 and a physically large 4] conditions), and no facilitation (neutral [e.g., a physically small 2 and a physically large 2] versus congruent) [3]. Previous imaging studies determined the intraparietal sulcus (IPS) as a central area for numerical processing [4–11]. A few studies tried to identify the brain dysfunction underlying developmental dyscalculia but yielded mixed results regarding the involvement of the left [12] or the right [13] IPS. Here we applied fMRI-guided TMS neuronavigation to disrupt left- or right-IPS activation clusters in order to induce dyscalculic-like behavioral deficits in healthy volunteers. Automatic magnitude processing was impaired only during disruption of right-IPS activity. When using the identical paradigm with dyscalculic participants, we reproduced a result pattern similar to that obtained with nondyscalculic volunteers during right-IPS disruption. These findings provide direct evidence for the functional role of right IPS in automatic magnitude processing.

Item does not contain fulltext This study tested the predictive value of attentional bias, emotion recognition, automatic associations, and response inhibition, in the assessment of in-clinic violent incidents. Sixty-nine male forensic patients participated and completed an Emotional Stroop to measure attentional bias for threat and aggression, a Single Target - Implicit Association Task to assess automatic associations, a Graded Emotional Recognition Task to measure emotion recognition, and an Affective Go/NoGo to measure response inhibition. Violent incidents were derived from patient files and scored on severity level. The predictive value of level of psychopathy was tested with the Psychopathy Checklist - Revised (PCL-R). Generalized linear mixed model analyses showed that increased attention towards threat and aggression, difficulty recognizing sad faces and factor 2 of the PCL-R predicted the sum of violent incidents. Specifically, verbal aggression was predicted by increased attention towards threat and aggression, difficulty to recognize sad and happy faces, and PCL-R factor 2; physical aggression by decreased response inhibition, higher PCL-R factor 2 and lower PCL-R factor 1 scores; and aggression against property by difficulty recognizing angry faces. Findings indicate that cognitive tasks could be valuable in predicting aggression, thereby extending current knowledge on dynamic factors predicting aggressive behavior in forensic patients. 9 p.

Recent evidence has revealed an advantage for movements to last target positions in a structured visual display, suggesting a mediating role of allocentric, in addition to egocentric, information in goal-directed reaching. This notion is accommodated by the recently updated perception-action model (Milner and Goodale, 2008), which postulates functional roles of ventral and dorsal neural areas in allocentric coding. In the present study, we used imaging-guided multi-site continuous theta burst stimulation (cTBS) over regions of the ventral and dorsal processing streams to unravel their functional contribution on visually guided reaching in two display conditions: the "egocentric" condition where the target appeared in an empty display and the "allocentric" condition where the target appeared in a structured display with placeholders marking possible target locations. Cortical sites for cTBS were identified individually for each participant via coregistration with magnetic resonance scans. Results indicated that cTBS in the egocentric condition did not affect movement time, but cTBS in the allocentric condition modulated movement time contingent on stimulation site and target position. In particular, cTBS over the lateral occipital cortex (part of the ventral stream) and over the angular gyrus (part of the dorsal stream) eliminated the last-target advantage by slowing down reaching to the salient last target position. cTBS over the superior parietal occipital cortex did not affect the last-target advantage. These outcomes provide the first causal evidence for allocentric coding in ventral and dorsal routes during real-time reaching, thereby supporting the updated perception-action model. (C) 2015 Elsevier B.V. All rights reserved.

The noninvasive methods of cognitive neuroscience offer new possibilities to study language. We used neuronavigated multisite transcranial magnetic stimulation (TMS) to determine the functional relevance of 1) the posterior part of left superior temporal gyrus (Wernicke's area), 2) a midportion of Broca's area (slightly posterior/superior to apex of vertical ascending ramus), and 3) the midsection of the left middle temporal gyrus (MTG), during overt picture naming. Our chronometric TMS design enabled us to chart the time points at which neural activity in each of these regions functionally contributes to overt speech production. Our findings demonstrate that the midsection of left MTG becomes functionally relevant at 225 ms after picture onset, followed by Broca's area at 300 ms and Wernicke's area at 400 ms. Interestingly, during this late time window, the left MTG shows a second peak of functional relevance. Each area thus contributed during the speech production process at different stages, suggesting distinct underlying functional roles within this complex multicomponential skill. These findings are discussed and framed in the context of psycholinguistic models of speech production according to which successful speaking relies on intact, spatiotemporally specific feed forward and recurrent feedback loops within a left-hemispheric fronto-temporal brain connectivity network.

Recent psychophysics studies suggest that the behavioral impact of a visual stimulus and its conscious visual recognition underlie two functionally dissociated neuronal processes. Previous TMS studies have demonstrated that certain features of a visual stimulus can still be processed despite TMS-induced disruption of perception. Here, we tested whether symbolic action priming also remains intact despite TMS-induced masking of the prime. We applied single-pulse TMS over primary visual cortex at various temporal intervals from 20 ms to 120 ms during a supraliminal action priming paradigm. This TMS protocol enabled us to identify at what exact time point a TMS-induced activity disruption of primary visual cortex interferes with conscious visual perception of the prime versus (un)conscious behavioral priming of the visual target stimulus. We also introduced spatial uncertainty by presenting visual stimuli either above or below the fixation cross, while the TMS pulse was always targeting the prime presented below fixation. We revealed that TMS over primary visual cortex interferes with both conscious visual perception and symbolic behavioral priming in a temporarily and spatially specific manner, i.e., only when disrupting primary visual cortex at approximately the same temporal stage between 60 and 100 ms after prime onset, and only for those prime stimuli presented below fixation. These findings are in disagreement with the idea of subliminal action priming being mediated by neural pathways bypassing striate cortex, and rather suggest that symbolic action priming relies on an intact neural transmission along the retino-geniculo-striate pathway. The implications of our findings for previous reports of residual visual processing during striate TMS are discussed.

An event-related brain potentials (ERP) experiment was carried out to investigate the influence of semantic category membership on syntactic decision-making. Native speakers of German viewed a series of words that were semantically marked or unmarked for gender and made go/no-go decisions about the grammatical gender of those words. The electrophysiological results indicated that participants could make a gender decision earlier when words were semantically gender-marked than when they were semantically gender-unmarked. Our data provide evidence for the influence of semantic category membership on the decision of the syntactic gender of a visually presented German noun. More specifically, our results support models of language comprehension in which semantic information processing of words is initiated prior to syntactic information processing is finalized.

BACKGROUND: Human motor behaviors are characterized by both, reactive and proactive mechanisms. Yet, studies investigating the neural correlates of motor behavior almost exclusively focused on reactive motor processes. Here, we employed the pro-/anti-cue motor preparation paradigm to systematically study proactive motor control in an imaging environment. In this paradigm, either pro- or anti-cues are presented in a blocked design. Four fingers (two from each hand) are mapped onto four visual target locations. Visual targets require a speeded response by one corresponding finger, but, most importantly, they are preceded by visual cues that are congruent ("pro-cue"), incongruent ("anti-cue"), or neutral with respect to the responding hand. With short cue-target intervals, congruence effects are based on automatic motor priming of the correct hand (in case of pro-cues) or incorrect hand (in case of anti-cues), generating, respectively, reaction time benefits or reaction time costs relative to the neutral-cue. With longer cue-target intervals, slower top-down processes become effective, transforming early anti-cue interference into late anti-cue facilitation.METHODS: We adapted this paradigm to be compatible with neuroimaging, tested and validated it behaviorally-both inside and outside the imaging environment-and implemented it in a whole-brain functional magnetic resonance imaging study.RESULTS AND CONCLUSION: Our imaging results indicate that pro-cues elicited much less neural activation than did anti-cues, the latter recruiting well-known cognitive top-down networks related to attention, response inhibition, and error monitoring/signaling, thereby revealing high-level influences on proactive motor processes.

The aim of this study was to identify implicit cognitive predictors of aggressive behavior. Specifically, the predictive value of an attentional bias for aggressive stimuli and automatic association of the self and aggression was examined for reactive and proactive aggressive behavior in a non-clinical sample (N = 90). An Emotional Stroop Task was used to measure an attentional bias. With an idiographic Single-Target Implicit Association Test, automatic associations were assessed between words referring to the self (e.g., the participants' name) and words referring to aggression (e.g., fighting). The Taylor Aggression Paradigm (TAP) was used to measure reactive and proactive aggressive behavior. Furthermore, self-reported aggressiveness was assessed with the Reactive Proactive Aggression Questionnaire (RPQ). Results showed that heightened attentional interference for aggressive words significantly predicted more reactive aggression, while lower attentional bias towards aggressive words predicted higher levels of proactive aggression. A stronger self-aggression association resulted in more proactive aggression, but not reactive aggression. Self-reports on aggression did not additionally predict behavioral aggression. This implies that the cognitive tests employed in our study have the potential to discriminate between reactive and proactive aggression. Aggr. Behav. 41:51-64 2015. © 2014 Wiley Periodicals, Inc.

The ability to inhibit action tendencies is vital for adaptive human behaviour. Various paradigms are supposed to assess action inhibition and are often used interchangeably. However, these paradigms are based on different conceptualizations (action restraint vs. action cancellation) and the question arises as to what extent different conceptualizations of inhibitory processing are mirrored in a distinct neural activation pattern. We used functional magnetic resonance imaging to investigate the neural correlates of action restraint vs. action cancellation. Analyses of local activity changes as well as network connectivity measures revealed a strong overlap of activation within a common action inhibition network including inferior frontal, pre-supplementary motor and thalamic brain areas as well as the anterior cingulate cortex. Furthermore, our findings pointed to additional neural networks that are distinct for action restraint (i.e. right superior frontal gyrus, left middle frontal gyrus, and bilateral anterior cingulate cortex) and action cancellation (i.e. right middle frontal gyrus, posterior cingulate cortex, and parietal regions). Our connectivity analyses showed that different inhibitory modalities largely relied on a task-independent global inhibition network within the brain. Furthermore, they suggested that the conceptually distinct inhibitory aspects of action restraint vs. action cancellation also activated additional specific brain regions in a task-dependent manner. This has implications for the choice of tasks in an empirical setting, but is also relevant for various clinical contexts in which inhibition deficits are considered a diagnostic feature.

Peters JC, Reithler J, Schuhmann T, de Graaf T, Uludag. K, Goebel R, Sack AT. On the feasibility of concurrent human TMS-EEG-fMRI measurements. J Neurophysiol 109: 1214-1227, 2013. First published December 5, 2012; doi:10.1152/jn.00071.2012.-Simultaneously combining the complementary assets of EEG, functional MRI (fMRI), and transcranial magnetic stimulation (TMS) within one experimental session provides synergetic results, offering insights into brain function that go beyond the scope of each method when used in isolation. The steady increase of concurrent EEG-fMRI, TMS-EEG, and TMS-fMRI studies further underlines the added value of such multimodal imaging approaches. Whereas concurrent EEG-fMRI enables monitoring of brain-wide network dynamics with high temporal and spatial resolution, the combination with TMS provides insights in causal interactions within these networks. Thus the simultaneous use of all three methods would allow studying fast, spatially accurate, and distributed causal interactions in the perturbed system and its functional relevance for intact behavior. Concurrent EEG-fMRI, TMS-EEG, and TMS-fMRI experiments are already technically challenging, and the three-way combination of TMS-EEG-fMRI might yield additional difficulties in terms of hardware strain or signal quality. The present study explored the feasibility of concurrent TMS-EEG-fMRI studies by performing safety and quality assurance tests based on phantom and human data combining existing commercially available hardware. Results revealed that combined TMS-EEG-fMRI measurements were technically feasible, safe in terms of induced temperature changes, allowed functional MRI acquisition with comparable image quality as during concurrent EEG-fMRI or TMS-fMRI, and provided artifact-free EEG before and from 300 ms after TMS pulse application. Based on these empirical findings, we discuss the conceptual benefits of this novel complementary approach to investigate the working human brain and list a number of precautions and caveats to be heeded when setting up such multimodal imaging facilities with current hardware.

Accompanying source data for the publication entitled “Concurrent human TMS-EEG-fMRI enables monitoring of oscillatory brain state-dependent gating of cortico-subcortical network activity” (Peters, Reithler et al., 2020, Communications Biology). In all filenames, P1 and P2 indicate (“high-activators”) participant 1 and 2, respectively. Dataset 1 (fig1_fMRI_data.rar; 5 files) contains the fMRI data underlying Fig1: 'P2_ADNI_IIHC_ACPC.vmr': anatomical MRI file (BrainVoyager format) on which the *.vmp files can be superimposed. ‘P2_FingerTap_vs_AudioOnly.vmp’: statistical map fMRI file (BrainVoyager format) containing the GLM contrast between activity in the Motor Execution task and the control task (only auditory cues but no motor activity). This statistical map contains the whole brain image, of which a transversal slice is shown in Fig 1a. 'P2_FTvsBsln_ROIrPMd.dat': text file containing the average time courses of Motor Execution-events (FingerTapping, FT) in rPMd, shown in inset of Fig1a. Note that the header contains plotting information (BrainVoyager format). The / section contains the means (column 1) and standard errors (column 2) per datapoint for the Motor Execution task (section 1 "Curve 1: FingerTap") and the control task (section2 "Curve 2: Audio"). 'P2_R1-5_allTMS_vs_bsln.vmp': statistical map fMRI file (BrainVoyager format) containing the GLM contrast between activity in TMS-events and baseline (rest). This statistical map contains the whole brain image, of which a transversal slice is shown in Fig 1c. 'P2_AllTMSvsBsln_ROIrPMd.dat': text file containing the average time courses of TMS-events in rPMd, shown in inset of Fig1c. Data format similar to *.dat file above. Dataset 2 (fig2_fMRI_data.rar; 36 files) contains the fMRI data underlying Fig2: *.vmr': anatomical MRI file (BrainVoyager format), which is inhomogeneity corrected (abbreviated in filename as “IIHC”) and transformed to ACPC space (in filename: “ACPC”). Other abbreviations in the filename indicate the following: ‘subcortical_segmentation’: segmentation of the subcortical ROIs ‘LH’: left hemisphere ‘RH’: right hemisphere *.srf/.svp': Smoothed mesh reconstructions (anatomical MRI file; BrainVoyager format) of the entire cortex as well as reconstructions of the cortical and subcortical Regions-of-Interest (ROIs). Each *.srf file contains a mesh surface reconstruction and is accompanied by a *.svp file with the same filename. The *.svp contains the “surface viewpoint” settings (BrainVoyager format), which position the surface and lightning conditions to recreate Fig 2. However, note that the *.srf file can also be used without *.svp files. Filename conventions are identical to vmr files. Additional abbreviations in the filename indicate the following: (sub)cortical_ME_ROIs: (sub)cortical Motor Execution (ME) ROIs (sub)cortical_TMS_ROIs: (sub)cortical TMS- responsive (TMS) ROIs Dataset 3 (Fig3and4_Matlab_data.rar; 5 files) contains the matlab data and corresponding code (related to the EEG-informed fMRI analyses) to generate Fig3 and Fig4: 'fMRIactivity_AlphaClasses.mat': matlab file containing the 5-dimensional array ‘Alpha_TrialsxPowerClassxROITypexROIsxSubj’. The 5 dimensions represent: 1) TMS-evoked BOLD responses (indexed by their average beta value) in 40 trials, 2) weak and strong power class, 3) Motor Execution and TMS-responsive ROIs, 4) cortical and subcortical ROIs ('rPMd','lPMd','rM1','SMA','rCN','rPut','rThal','lThal','lPut','lCN'), 5) Participants. 'Plot_Paper_Fig3.m': matlab code textfile to generate Figure 3 which shows that TMS-induced BOLD changes in cortical ROIs depend on pre-TMS alpha power. See comments in m-file for details. By running the code, a figure is created and saved as ‘Fig3.fig’. 'Plot_Paper_Fig4.m': matlab code textfile to generate Figure 4 which shows that also in subcortical ROIs, TMS-induced BOLD changes depend on pre-TMS alpha power. See comments in m-file for details. By running the code, a figure is created and saved as ‘Fig4.fig’. ‘Fig3.fig’: Figure resulting from running script 'Plot_Paper_Fig3.m'. ‘Fig4.fig’: Figure resulting from running script 'Plot_Paper_Fig4.m'., v2: Barplot_fMRIrespperCorticalROI_fig3.m and Barplot_fMRIrespperSubCorticalROI_fig4.m have nearly the same functionality as Plot_Paper_Fig3.m and Plot_Paper_Fig4.m respectively but offer an alternative way to visualize the single-trial data