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Interruptions lead to a deterioration of primary task performance. Applied research usually describes a delay in primary task resumption as an essential component of this performance deficit. Here, we investigate this approach using electrophysiological correlates of the focusing of attention within working memory, a process that is fundamental to switching between different tasks. A lateralized working memory task was frequently interrupted by either a high- or low-demanding arithmetic task and a subsequent retrospective cue indicated the working memory item required for later report. The detrimental effect of interruptions on primary task performance was most pronounced for high-demanding interruptions. After retro-cue presentation, fronto-central theta power (4–7 Hz) was lowest following high-demanding interruptions and posterior alpha power (8–14 Hz) was less suppressed in the two interruption conditions. These effects might be related to a deficit in attentional control processes following the retrospective cue. Furthermore, we introduce the suppression of posterior alpha power contralateral to the remembered primary task stimuli during the interruption phase as a temporal marker for primary task resumption. Especially for cognitively demanding interruption tasks, this effect seems to overlap in time with the processing of the interruption, which should contribute to the primary task performance deficit.

The ability to flexibly manipulate memory representations is embedded in visual working memory (VWM) and can be tested using paradigms with retrospective cues. While valid retrospective cues often facilitate memory recall, invalid ones may or may not result in performance costs. We investigated individual differences in utilising retrospective cues and evaluated how these individual differences are associated with brain oscillatory activity at rest. At the behavioural level, we operationalised flexibility as the ability to make effective use of retrospective cues or disregard them if required. At the neural level, we tested whether individual differences in such flexibility were associated with properties of resting-state alpha oscillatory activity (8-12 Hz). To capture distinct aspects of these brain oscillations, we evaluated their power spectral density and temporal dynamics using long-range temporal correlations (LRTC). In addition, we performed multivariate patterns analysis (MVPA) to classify individuals' level of behavioural flexibility based on these neural measures. We observed that alpha power alone (magnitude) at rest was not associated with flexibility. However, we found that the participants’ ability to manipulate VWM representations was correlated with alpha LRTC and could be decoded using MVPA on patterns of alpha power. Our findings suggest that alpha LRTC and multivariate patterns of alpha power at rest may underlie some of the individual differences in using retrospective cues in working memory tasks.

Objective Interictal epileptiform discharges (IEDs) were shown to be associated with cognitive impairment in persons with epilepsy. Previous studies indicated that IED rate, location, timing, and spatial relation to the seizure onset zone could predict an IED's impact on memory encoding and retrieval if they occurred in lateral temporal, mesial temporal, or parietal regions. In this study, we explore the influence that other IED properties (e.g., amplitude, duration, white matter classification) have on memory performance. We were specifically interested in investigating the influence that lateral temporal IEDs have on memory encoding. Methods Two hundred sixty-one subjects with medication-refractory epilepsy undergoing intracranial electroencephalographic monitoring performed multiple sessions of a delayed free-recall task (n = 671). Generalized linear mixed models were utilized to examine the relationship between IED properties and memory performance. Results We found that increased IED rate, IEDs propagating in white matter, and IEDs localized to the left middle temporal region were associated with poorer memory performance. For lateral temporal IEDs, we observed a significant interaction between IED white matter categorization and amplitude, where IEDs with an increased amplitude and white matter propagation were associated with reduced memory performance. Additionally, changes in alpha power after an IED showed a significant positive correlation with memory performance. Significance Our results suggest that IED properties may be useful for predicting the impact an IED has on memory encoding. We provide an essential step toward understanding pathological versus potentially beneficial interictal epileptiform activity.

A large body of research suggests that early event-related potentials (ERPs), such as the P1 and N1, are potentiated by attention and represent stimulus amplification. However, recent accounts suggest that the P1 is associated with inhibiting the irrelevant visual field evidenced by a pronounced ipsilateral P1 during sustained attention to peripherally presented stimuli. The current EEG study further investigated this issue to reveal how lateralized ERP findings are modulated by face and emotional information. Therefore, participants were asked to fixate the center of the screen and pay sustained attention either to the right or left visual field, where angry or neutral faces or their Fourier phase-scrambled versions were presented. We found a bilateral P1 to all stimuli with relatively increased, but delayed, ipsilateral P1 amplitudes to faces but not to scrambles. Explorative independent component analyses dissociated an earlier lateralized larger contralateral P1 from a later bilateral P1. By contrast, the N170 showed a contralateral enhancement to all stimuli, which was most pronounced for neutral faces attended in the left hemifield. Finally, increased contralateral alpha power was found for both attended hemifields but was not significantly related to poststimulus ERPs. These results provide evidence against a general inhibitory role of the P1 but suggest stimulus-specific relative enhancements of the ipsilateral P1 for the irrelevant visual hemifield. The lateralized N170, however, is associated with stimulus amplification as a function of facial features.

Mind wandering during ongoing tasks can impede task performance and increase the risk of failure in the laboratory as well as in daily‐life tasks and work environments. Neurocognitive measures like the electroencephalography (EEG) offer the opportunity to assess mind wandering non‐invasively without interfering with the primary task. However, the literature on electrophysiological correlates of mind wandering is rather inconsistent. The present study aims toward clarifying this picture by breaking down the temporal dynamics of mind wandering encounters using a cluster‐based permutation approach. Participants performed a switching task during which mind wandering was occasionally assessed via thought probes applied after trial completion at random time points. In line with previous studies, response accuracy was reduced during mind wandering. Moreover, alpha power during the inter‐trial interval was a significantly increased on those trials on which participants reported that they had been mind‐wandering. This spatially widely distributed effect is theoretically well in line with recent findings linking an increased alpha power to an internally oriented state of attention. Measurements of alpha power may, therefore, be used to detect mind wandering online during critical tasks in traffic and industry in order to prevent failures.

Delineating the neural correlates of sensory awareness is a key requirement for developing a neuroscientific understanding of consciousness. A neural signal that has been proposed as a key neural correlate of awareness is amplitude reduction of 8-14 Hz alpha oscillations. Alpha oscillations are also closely linked to processes of spatial attention, providing potential alternative explanations for past results associating alpha oscillations with awareness. We employed a no-report inattentional blindness (IB) paradigm with electroencephalography to examine the association between awareness and the power of 8-14 Hz alpha oscillations. We asked whether the alpha-power decrease commonly reported when stimuli are perceived is related to awareness, or other factors that commonly confound awareness investigations, specifically task-relevance and visual salience. Two groups of participants performed a target discrimination task at fixation while irrelevant non-salient shape probes were presented briefly in the left or right visual field. One group was explicitly informed of the peripheral probes at the commencement of the experiment (the control group), whereas the other was not told about the probes until halfway through the experiment (IB group). Consequently, the IB group remained unaware of the probes for the first half of the experiment. In all conditions in which participants were aware of the probes, there was an enhanced negativity in the event-related potential (the visual awareness negativity). Furthermore, there was an extended contralateral alpha-power decrease when the probes were perceived, which was not present when they failed to reach awareness. These results suggest alpha oscillations are intrinsically associated with awareness itself.

Recent studies have related enhancements of theta- (∼4-8 Hz) and alpha-power (∼8-13 Hz) to listening effort based on parallels between enhancement and task difficulty. In contrast, nonauditory works demonstrate that, although increases in difficulty are initially accompanied by increases in effort, effort decreases when a task becomes so difficult as to exceed one's ability. Given the latter, we examined whether theta- and alpha-power enhancements thought to reflect effortful listening show a quadratic trend across levels of listening difficulty from impossible to easy. Listeners (n = 14) performed an auditory delayed match-to-sample task with frequency-modulated tonal sweeps under impossible, difficult (at ∼70.7% correct threshold), and easy (well above threshold) conditions. Frontal midline theta-power and posterior alpha-power enhancements were observed during the retention interval, with greatest enhancement in the difficult condition. Independent component-based analyses of data suggest that theta-power enhancements stemmed from medial frontal sources at or near the anterior cingulate cortex, whereas alpha-power effects stemmed from occipital cortices. Results support the notion that theta- and alpha-power enhancements reflect effortful cognitive processes during listening, related to auditory working memory and the inhibition of task-irrelevant cortical processing regions, respectively. Theta- and alpha-power dynamics can be used to characterize the cognitive processes that make up effortful listening, including qualitatively different types of listening effort.

Background Driver age and blood alcohol concentration are both important factors in predicting driving risk; however, little is known regarding the joint import of these factors on neural activity following socially relevant alcohol doses. We examined age and alcohol effects on brain oscillations during simulated driving, focusing on 2 region-specific frequency bands implicated in task performance and attention: parietal alpha power (PAP; 8 to 12 Hz) and frontal theta power (FTP; 4 to 7 Hz). Methods Participants included 80 younger (aged 25 to 35 years) and 40 older (aged 55 to 70 years) community-dwelling, moderate drinkers. Participants consumed placebo, low, or moderate doses of alcohol designed to achieve target peak breath alcohol concentrations of 0, 0.04, or 0.065 g/dl, respectively. Electrophysiological measures were recorded during engagement in a simulated driving task involving 4 scenarios of varied environmental complexity. Results A main effect of age was detected in FTP, but neither an alcohol effect nor interactions were observed. For PAP, an age-by-alcohol interaction was detected. Relative to placebo controls, older and younger participants receiving low-dose (0.04 g/dl) alcohol evinced divergent PAP alterations, with a pattern of higher power among older participants and lower power among younger participants. This interaction was noted across the varied environmental contexts. Conclusions These findings are consistent with the hypothesis that compared with younger individuals, older drivers may be differentially susceptible to alcohol effects. While these age-by-alcohol interactions in neural activity are provocative, further investigation exploring the mechanisms and behavioral correlates of these effects will be crucial in determining their behavioral impact.

Recent research has related the orienting of selective attention to the lateralization of posterior EEG alpha power (∼8 to 12 Hz). Typically, alpha power decreases over the side of the head contralateral to the cued side of space. However, it is not clear how this lateralization affects behavior. We recorded EEG from 20 participants while they performed a cued visual discrimination task under three different response-deadline conditions to investigate the effect of alpha-power modulation on behavioral performance in more detail. Although all participants benefited from the cue behaviorally and adjusted their performance according to the response deadlines, we found the cue-related alpha-power modulation to depend on the general alpha-power level at baseline: Only participants with high baseline alpha power showed significant cue-related alpha-power lateralization that was, however, strikingly similar across response-deadline conditions. On the other hand, participants with low alpha power at baseline did not show any lateralization, but adjusted their alpha levels according to the response-deadline instructions and, more importantly, showed a stronger influence of the task instructions on behavioral performance and adapted their response accuracies to the task requirements more flexibly. These findings challenge the often-assumed role of alpha-power lateralization for attentional deployment. While alpha power seems to be related to behavioral performance and the orienting of attention, this relationship is rather complex and, at least under the current task requirements, the general alpha-power state seems to be more strongly related to behavioral performance (in our case, the flexible adjustment to task requirements) than the cue-related lateralization.

Unexpected novel sounds capture one's attention, even when irrelevant to the task pursued (e.g., playing video game). This often comes at a cost to the task (e.g., slower responding). The neural basis for this behavioral distraction effect is not well understood and is subject of this study. Our approach was motivated by findings from cuing paradigms suggesting a link between modulations in oscillatory activity and voluntary attention shifts. The current study tested whether oscillatory activity is also modulated by a task-irrelevant auditory distractor, reflecting a neural signature of an involuntary shift of attention and accounting for the impaired task performance. We reanalyzed magnetoencephalographic data collected via an auditory-visual distraction paradigm in which a task-relevant visual stimulus was preceded by a task-irrelevant sound on each trial. In 87.5% this was a regular sound (Standard); in 12.5% this was a novel sound (Distractor). We compared nonphase locked oscillatory activity in a time window prior to the visual target as a function of the experimental manipulation (Distractor, Standard). We found low power in the pretarget time window for Distractors compared to Standards in the alpha and beta frequency bands. Importantly, individual alpha power correlated with response speed on a trial-by-trial basis for the Distractor only. Sources were localized to the occipital cortex, and also to the parietal and supratemporal cortices. These findings support our hypothesis that the distractor-related alpha power modulation indexes an involuntary shift of attention which accounts for the impaired task performance.

Recent studies have linked variability in near-threshold stimulus detection to fluctuations in the prestimulus EEG alpha power (α, ∼8-12 Hz). Typically, these studies rely on hit rate as a measure of detection performance and show that detection is enhanced when α power is low compared to when it is high. However, hit rates are determined by both sensitivity to the stimulus and the placement of the response criterion. Here, we investigated the relationships between prestimulus α power and variability in these two measures on a single-trial basis. We confirm earlier reports that detection is inversely related to power in the individual α-frequency band. However, our results show a stronger relationship between α power and response criterion than with sensitivity. Higher α power was related to a more conservative response criterion (i.e., more "no" responses). A response criterion that varies depending on α power might help to optimize performance in an excited state and protect against false positives in a relatively disengaged state.

To efficiently perceive and respond to the external environment, our brain has to perceptually integrate or segregate stimuli of different modalities. The temporal relationship between the different sensory modalities is therefore essential for the formation of different multisensory percepts. In this magnetoencephalography study, we created a paradigm where an audio and a tactile stimulus were presented by an ambiguous temporal relationship so that perception of physically identical audiotactile stimuli could vary between integrated (emanating from the same source) and segregated. This bistable paradigm allowed us to compare identical bimodal stimuli that elicited different percepts, providing a possibility to directly infer multisensory interaction effects. Local differences in alpha power over bilateral inferior parietal lobules (IPLs) and superior parietal lobules (SPLs) preceded integrated versus segregated percepts of the two stimuli (audio and tactile). Furthermore, differences in long-range cortical functional connectivity seeded in rIPL (region of maximum difference) revealed differential patterns that predisposed integrated or segregated percepts encompassing secondary areas of all different modalities and prefrontal cortex. We showed that the prestimulus brain states predispose the perception of the audiotactile stimulus both in a global and a local manner. Our findings are in line with a recent consistent body of findings on the importance of prestimulus brain states for perception of an upcoming stimulus. This new perspective on how stimuli originating from different modalities are integrated suggests a non-modality specific network predisposing multisensory perception.

Previous electroencephalographic studies have identified premovement high‐alpha power as a predictor of movement accuracy; less frontal‐central high‐alpha power is associated with accurate movements (e.g., holed golf putts), and could reflect more cognitive resources being allocated to response programming. The present experiment tested this interpretation. Ten expert and ten novice golfers completed 120 putts while high‐alpha power was recorded and analyzed as a function of whether the previous putt was holed (i.e., a correct response) or missed (i.e., an error). Existing evidence indicates that more resources are allocated to response programming following errors. We observed less premovement high‐alpha power following errors, especially in experts. Our findings provide indirect evidence that high‐alpha power is an inverse marker of the amount of resources allocated to motor response programming.

Error commission evokes changes in event-related potentials, autonomic nervous system activity, and behavior, presumably reflecting the operation of a cognitive control network. Here we test the hypothesis that errors lead to increased cortical arousal, measurable as changes in electroencephalogram (EEG) alpha band power. Participants performed a Stroop task while EEG was recorded. Following correct responses, alpha power increased and then decreased in a quadratic pattern, implying transient mental disengagement during the intertrial interval. This trend was absent following errors, which elicited significantly less alpha power than correct trials. Moreover, post-error alpha power was a better predictor of individual differences in post-error slowing than the error-related negativity (ERN), whereas the ERN was a better predictor of post-error accuracy than alpha power. These findings imply that changes in cortical arousal play a unique role in modulating post-error behavior.

Experiments examining asymmetrical frontal activity in response to affective pictures have produced inconsistent results. These inconsistencies may have occurred because the pictorial stimuli may not have evoked strong emotional or motivational tendencies for all individuals. In the current study, participants were asked to indicate their liking for dessert and the time since they had last eaten to assess individual differences in emotion and motivation. Then, they were shown dessert pictures or neutral pictures while EEG activity was recorded. Results indicated that the individual differences predicted greater left than right frontal activity (inverse of the alpha power) within the first second as well as all 12 s of viewing of the dessert pictures.

The aim of this study was to investigate whether components of pain event-related potentials (ERPs) are modulated by anxiety. Pain ERPs in response to electrical stimulation were collected from 14 healthy individuals in a neutral condition and a condition where pain-related anxiety was induced. The amplitude of the N140 component of the ERP was found to be larger in the anxiety condition than the neutral condition. Arousal, as indicated by alpha power, did not differ between conditions. Differences in valence and focused attention to the painful stimuli may account for the increases in the N140 in the anxiety condition.

Recent associative models of cognitive control hypothesize that cognitive control can be learned (optimized) for task-specific settings via associations between perceptual, motor, and control representations, and, once learned, control can be implemented rapidly. Midfrontal brain areas signal the need for control, and control is subsequently implemented by biasing sensory representations, boosting or suppressing activity in brain areas processing task-relevant or task-irrelevant information. To assess the timescale of this process, we employed EEG. In order to pinpoint control implementation in specific sensory areas, we used a flanker task with incongruent flankers shown in only one hemifield (congruent flankers in the other hemifield) isolating their processing in the contralateral hemisphere. ERPs revealed fast modulations specifically in visual processing areas contralateral to the incongruent flankers. To test whether these modulations reflect increased or decreased processing of incongruent flankers, we investigated alpha power, a marker for attentional inhibition. Importantly, we show increased alpha power over visual areas processing incongruent flankers from 300 to 500 ms poststimulus onset. This suggests fast cognitive control by attentional inhibition for information disrupting goal-oriented actions. Additionally, we show that midfrontal theta earlier in the trial is also modulated by incongruency, and that theta power predicts subsequent alpha power modulations. This supports the hypothesis that midfrontal incongruency detection leads to control implementation, and reveals that these mechanisms take place on a fast, within-trial timescale.

Blink rates (BR) and alpha brain waves were studied in 13 schizophrenic and 13 healthy smokers under conditions of smoking deprivation as well as smoking saturation and under different task conditions of smooth pursuit eye movements. Task conditions significantly changed BR and alpha power; smoking enhanced BR and alpha frequency, the latter effect being especially pronounced in schizophrenics for F3-F4 leadings. Concerning BR, groups differed significantly as long as smoking quantity was not statistically controlled. BR, alpha power and smoking quantity were consistently correlated above chance levels. Results are discussed with respect to the blink alpha neurocircuit model.