Biology subjects

Mazaheri, A.

Publications and source records attributed to Mazaheri, A..

18 recordsLinked to original sources

bioRxiv2024

It's the Sound not the Pulse: Peripheral Magnetic Stimulation Reduces Central Sensitization through Auditory Modulatory Effects

Repetitive peripheral magnetic stimulation (rPMS) is a non-pharmacological, non-invasive analgesic modality with limited side effects. However, there is a paucity of controlled studies demonstrating its efficacy compared to existing pain management tools. Here, in an initial sample of 100 healthy participants (age 18-40), we compared the analgesic efficacy of two rPMS stimulation protocols--continuous theta burst stimulation (ctbPMS) and intermittent TBS (itbPMS)--against transcutaneous electric nerve stimulation (TENS), a peripheral stimulation technique that is commonly used for pain management. We also included a sham rPMS protocol where participants heard the sound of rPMS stimulation while the coil was placed over their arm, but received no peripheral stimulation. We hypothesized that itbPMS and ctbPMS--but not sham--would reduce pain intensity, pain unpleasantness, and secondary hyperalgesia evoked by a phasic heat pain (PHP) paradigm on the volar forearm with similar efficacy to TENS. Neither rPMS nor TENS reduced reported pain intensity or unpleasantness (p>0.25). However, ctbPMS and itbPMS significantly reduced the area of secondary hyperalgesia, whereas TENS did not (F3,96= 4.828, p= 0.004). Unexpectedly, sham rPMS, which involved auditory but no peripheral nerve stimulation, also significantly reduced secondary hyperalgesia compared to TENS. We performed a second study (n=32) to investigate auditory contributions to rPMS analgesia. Masking the rPMS stimulation sound with pink noise eliminated its analgesic effect on secondary hyperalgesia (p=0.5). This is the first study to show that the analgesic properties of rPMS in acute experimental pain may be largely attributed to its auditory component rather than peripheral nerve stimulation.

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bioRxiv2023

Can non-invasive brain stimulation modulate peak alpha frequency in the human brain? A systematic review and meta-analysis

Peak alpha frequency, the dominant oscillatory frequency within the alpha range (8-12 Hz), is associated with cognitive function and several neurological conditions, including chronic pain. Manipulating PAF could offer valuable insight into the relationship between PAF and various functions and conditions and provide new treatment avenues. This systematic review aimed to comprehensively synthesise effects of non-invasive brain stimulation (NIBS) on PAF speed. Relevant studies assessing PAF pre- and post-NIBS in healthy adults were identified through systematic searches of electronic databases (Embase, PubMed, PsychINFO, Scopus, The Cochrane Library) and trial registers. The Cochrane risk-of-bias tool was employed for assessing study quality. Quantitative analysis was conducted through pairwise meta-analysis when possible; otherwise, qualitative synthesis was performed. The review protocol was registered with PROSPERO (CRD42020190512) and the Open Science Framework (https://osf.io/2yaxz/). Eleven NIBS studies were included, all with a low risk-of-bias, comprising seven transcranial alternating current stimulation (tACS), three repetitive transcranial magnetic stimulation (rTMS), and one transcranial direct current stimulation (tDCS) study. Meta-analysis of active tACS conditions (eight conditions from five studies) revealed no significant effects on PAF (mean difference [MD] = -0.12, 95% CI = -0.32 to 0.08, p = 0.24). Qualitative synthesis provided no evidence that tDCS altered PAF and moderate evidence for transient increases in PAF with 10 Hz rTMS. There is limited evidence that NIBS can modulate PAF, and existing evidence does not demonstrate robust effects. Further studies employing standardised stimulation protocols are necessary to determine the potential of NIBS to modulate PAF.

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bioRxiv2023

Brain-to-brain coupling forecasts future joint action outcomes

In this study, we investigated whether brain-to-brain coupling patterns could predict performance in a time-estimation task which requires two players to cooperate. The participant pairs, were tasked with synchronising button presses after converging on a shared representation of short, medium, and long time intervals while utilizing feedback to adjust responses. We employed EEG-hyperscanning and focused on post-feedback brain activity. We found that negative feedback led to increased frontal mid-line theta activity across individuals. Moreover, a correlation in post-feedback theta power between players forecasted failed joint action, while an anti-correlation forecasted success. These findings suggest that temporally coupled feedback related brain activity between two individuals serves as an indicator of redundancy in adjustment of a common goal representation. Additionally, the anti-correlation of this activity reflects cognitive strategic mechanisms that ensure optimal joint action outcomes. Rather than a paired overcompensation, successful cooperation requires flexible strategic agility from both partners.

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bioRxiv2023

Effects of nicotine compared to placebo gum on sensitivity to pain and mediating effects of peak alpha frequency

Recent research has linked individual peak alpha frequency (PAF) to pain sensitivity, but whether PAF alterations can influence pain remains unclear. Our study investigated the effects of nicotine on pain sensitivity and whether pain changes are mediated by PAF changes. In a randomised, double-blind, placebo-controlled experiment, 62 healthy adults (18-44 years) received either 4 mg nicotine (n=29) or placebo gum (n=33). Resting state EEG and pain ratings during prolonged heat and pressure models were collected before and after nicotine intake. The nicotine group showed a small decrease in heat-pain ratings compared to placebo group when controlling confounders, and a small increase in PAF across the scalp from pre- to post-gum, both with and without confounder adjustment. These effects were most pronounced in the central-parietal and right-frontal electrodes. However, mediation analysis did not support the notion that PAF changes mediate nicotines effects on pain sensitivity. While a growing body of literature supports a link between PAF and both acute and chronic pain, further work is needed to understand the mechanisms of this link.

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bioRxiv2022

Functional neural architecture of cognitive control mediates the relationship between individual differences in bilingual experience and behaviour

Bilinguals have often, but not always, been found to outperform monolinguals on domain-general attentional control. Inconsistent findings have been argued to stem, at least partly, from treating bilingualism as a uniform category and from not considering how neural adaptations to bilingual experiences modulate behavioural outcomes. The present study investigated how patterns of language experience, including language switching behaviour, duration and intensity/diversity of bilingual language use, influence the brain processes underlying cognitive control, and how these in turn translate to cognitive control performance. We examined reaction times and spectral dynamics of the electroencephalograms (EEG) of two-hundred-and-thirty-nine participants (about 70% bilinguals) with diverse language experiences during two cognitive control paradigms testing interference suppression (flanker and Simon task). Using structural equation modelling, we found that different bilingual experience factors were related with neurocognitive measures, which in turn were related with behavioural interference effects, for the flanker but not the Simon task. More specifically, increased frequency of language switching and intensity / diversity of bilingual language usage was negatively related to induced top-down control measures (especially midline-frontal theta), which in turn was beneficial for interference control. In contrast, duration of bilingual engagement correlated negatively with evoked bottom-up control measures (especially P3) and was therefore detrimental to interference control. We demonstrate here for the first time how the different factors of bilingual experience lead to different neural adaptations which impact behavioural outcomes. Significance statementLike other intensive experiences, bilingualism leads to brain adaptations. It results in structural changes in language areas, and, due to demands on language control, in brain areas associated with domain-general cognitive control. Related to this, bilinguals often outperform monolinguals on cognitive control tasks. But what is often ignored is that bilingualism is a multi-dimensional phenomenon, with variations such as diversity of language usage and duration of language use. The present large-scale study of neural functioning in bilingualism revealed for the first time how individual differences in bilingual experience lead to adaptations to brain functioning which in turn affect cognitive control behaviour. It exemplifies how the complexity of individual experiences plays a fundamental role in brain function.

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bioRxiv2022

Cross-modal alterations of Alpha Activity do not reflect inhibition of early sensory processing: A frequency tagging study

Selective attention involves prioritizing relevant sensory input while suppressing irrelevant stimuli. It has been proposed that oscillatory alpha-band activity ([~]10 Hz) aids this process by functionally inhibiting early sensory regions. However, recent studies have challenged this notion. Our EEG and MEG studies aimed to investigate whether alpha oscillations serve as a gatekeeper for downstream signal transmission. We first observed these effects in an EEG study and then replicated them using MEG, which allowed us to localize the sources. We employed a cross-modal paradigm where visual cues indicated whether upcoming targets required visual or auditory discrimination. To assess inhibition, we utilized frequency-tagging, simultaneously flickering the fixation cross at 36 Hz and playing amplitude-modulated white noise at 40 Hz during the cue-to-target interval. Consistent with prior research, we observed an increase in posterior alpha activity following cues signalling auditory targets. However, remarkably, both visual and auditory frequency tagged responses amplified in anticipation of auditory targets, correlating with alpha activity amplitude. Our findings suggest that when attention shifts to auditory processing, the visual stream remains responsive and is not hindered by occipital alpha activity. This implies that alpha modulation does not solely regulate gain control in early visual areas but rather orchestrates signal transmission to later stages of the processing stream.

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bioRxiv2021

Prolonged Pain Reliably Slows Peak Alpha Frequency by Reducing Fast Alpha Power

The relationship between the 8-12 Hz "alpha: rhythm, the predominant oscillatory activity of the brain, and pain remains unclear. In healthy individuals, acute, noxious stimuli suppress alpha power while patients with chronic pain demonstrate both enhanced alpha power and slowing of the peak alpha frequency (PAF). To investigate these apparent differences, EEG was recorded from healthy individuals while they completed two models of prolonged pain, Phasic Heat Pain and Capsaicin Heat Pain, at two testing visits occurring roughly 8 weeks apart. We report that PAF is reliably slowed and that alpha power is reliably decreased in response to prolonged pain. Furthermore, we show that alpha power changes, but not PAF changes, are fully reversed with stimulus removal suggesting that PAF slowing reflects pain associated states such as sensitization rather than the presence of ongoing pain. Finally, we provide evidence that changes to alpha power and PAF are due to power decreases in the "fast" (10-12 Hz) range of the alpha rhythm. This frequency dependent pain response aligns with the hypothesis that the alpha rhythm is composed of multiple, independent oscillators, and suggest that modulation of a putative "fast" oscillator may represent a promising therapeutic target for treating ongoing pain. In sum, we provide strong evidence that PAF is reliably slowed during prolonged pain and additionally identify a mechanism, "fast" alpha Power, which is responsible for these PAF changes.

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bioRxiv2021

Modulation in Alpha Band Activity Reflects Syntax Composition: An MEG Study of Minimal Syntactic Binding

Successful sentence comprehension requires the binding, or composition, of multiple words into larger structures to establish meaning. Using magnetoencephalography, we investigated the neural mechanisms involved in binding at the syntax level, in a task where contributions from semantics were minimized. Participants were auditorily presented with minimal sentences that required binding (pronoun and pseudo-verb with the corresponding morphological inflection; "she grushes") and pseudo-verb wordlists that did not require binding ("cugged grushes"). Relative to no binding, we found that syntactic binding was associated with a modulation in alpha band (8-12 Hz) activity in left-lateralized language regions. First, we observed a significantly smaller increase in alpha power around the presentation of the target word ("grushes") that required binding (-0.05s to 0.1s), which we suggest reflects an expectation of binding to occur. Second, during binding of the target word (0.15s to 0.25s), we observed significantly decreased alpha phase-locking between the left inferior frontal gyrus and the left middle/inferior temporal cortex, which we suggest reflects alpha-driven cortical disinhibition serving to strengthen communication within the syntax composition neural network. Together, our findings highlight the critical role of rapid spatial-temporal alpha band activity in controlling the allocation, transfer and coordination of the brains resources during syntax composition.

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bioRxiv2021

Bilingual speakers' enhanced monitoring can slow them down

Performance differences between bilinguals and monolinguals on conflict tasks can be affected by the balance of various sub-processes such as conflict monitoring and allocation of attentional resources for stimulus categorisation. Here we investigated the effect of bilingualism on these sub-processes during a conflict task with medium monitoring demand. We examined the behavioural responses and evoked potentials from bilinguals and monolinguals during a flanker task with 25% incongruent trials. We analysed behavioural differences by means of averaged response times and ex-Gaussian analyses of response time distributions. For the evoked potentials we focused on N2 (reflecting conflict monitoring) and P3 responses (reflecting allocation of attentional resources for cognitive control). We found that bilinguals had significantly longer response distribution tails compared to monolinguals. Additionally, bilinguals exhibited a more pronounced N2 and smaller P3 components compared to monolinguals, independent of experimental condition, suggesting a different balance of sub-processes for the two groups. It is suggested that bilinguals engaged more strongly in monitoring processes, leading to the allocation of fewer attentional resources during stimulus categorisation. Importantly, N2 amplitudes were positively and P3 amplitudes negatively related to the length of response distribution tails. We postulate that these results reflect an overactive monitoring system in bilinguals. This enhanced monitoring led to reduced engagement of attentional resources for stimulus categorisation, but also occasionally to slow responses. These results suggest that changes of the cognitive control system due to bilingual experience can change the balance of processes during conflict tasks, potentially leading to a small behavioural disadvantage.

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bioRxiv2021

How the healthy ageing brain supports semantic binding during language comprehension

Semantic binding refers to constructing complex meaning based on elementary building blocks. Using EEG, we investigated the age-related changes in modulations of oscillatory brain activity supporting lexical retrieval and semantic binding. Young and older adult participants were visually presented two-word phrases, which for the first word revealed a lexical retrieval signature (e.g. swift vs. swrfeq) and for the second word revealed a semantic binding signature (e.g. horse in a semantic binding "swift horse" vs. no binding "swrfeq horse" context). The oscillatory brain activity associated with lexical retrieval as well as semantic binding significantly differed between healthy older and young adults. Specifically for lexical retrieval, we found that different age groups exhibited opposite patterns of theta and alpha modulation, which as a combined picture suggest that lexical retrieval is associated with different and delayed signatures in older compared to young adults. For semantic binding, in young adults we found a signature in the low-beta range centred around the target word onset (i.e. a smaller low-beta increase for binding relative to no binding), while in healthy older adults we found an opposite binding signature about ~500ms later in the low- and high-beta range (i.e. a smaller low- and high-beta decrease for binding relative to no binding). The novel finding of a different and delayed oscillatory signature for semantic binding in healthy older adults reflects that the integration of word meaning into the semantic context takes longer and relies on different mechanisms in healthy older compared to young adults.

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bioRxiv2019

Differences in Early and Late Pattern-Onset Visual-Evoked Potentials between Self-Reported Migraineurs and Controls

Striped patterns have been shown to induce strong visual illusions and discomforts to migraineurs in the literature. Previous research has suggested that those unusual visual symptoms be linked with the hyperactivity on the visual cortex of migraine sufferers. The present study searched for evidence supporting this hypothesis by comparing the visual evoked potentials (VEPs) elicited by striped patterns of specific spatial frequencies (0.5, 3, and 13 cycles) between a group of 29 migraineurs (17 with aura/12 without) and 31 non-migraineurs. In addition, VEPs to the same stripped patterns were compared between non-migraineurs who were classified as hyperexcitable versus non-hyperexcitable using a previously established behavioural pattern glare task. We found that the migraineurs had a significantly increased N2 amplitude for stimuli with 13 cpd gratings but an attenuated late negativity (LN: 400 - 500 ms after the stimuli onset) for all the spatial frequencies. Interestingly, non-migraineurs who scored as hyperexcitable appeared to have similar response patterns. We proposed that the enhanced N2 could reflect disruption of the balance between parvocellular and magnocellular pathway, which is in support of a grating-induced cortical hyperexcitation mechanism on migraineurs. On the other hand, the attenuation of the late negativity could reflect a top-down feedback mechanism to suppress visual processing of an aversive stimulus.

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bioRxiv2019

Sensorimotor peak alpha frequency is a reliable biomarker of pain sensitivity

Previous research has observed that individuals with chronic pain demonstrate slower alpha band oscillations (8-12 Hz range) during resting electroencephalography (EEG) than do age-matched, healthy controls. While this slowing may reflect pathological changes within the brain that occur during the chronification of pain, an alternative explanation is that healthy individuals with slower alpha frequencies are more sensitive to prolonged pain, and by extension, more susceptible to developing chronic pain. To formally test this hypothesis, we examined the relationship between the pain-free, resting alpha frequency of healthy individuals and their subsequent sensitivity to two experimental models of prolonged pain, Phasic Heat Pain and Capsaicin Heat Pain, at two testing visits separated by 8 weeks on average (n = 61 Visit 1, n = 46 Visit 2). We observed that the speed of an individuals pain-free alpha oscillations was negatively correlated with sensitivity to both prolonged pain tests and that this relationship was reliable across short (minutes) and long (weeks) timescales. Furthermore, we used the speed of pain-free alpha oscillations to successfully identify those individuals most sensitive to prolonged pain, which we also validated on data from a separate, independent study. These results suggest that alpha oscillation speed is a reliable biomarker of prolonged pain sensitivity with the potential to become a tool for prospectively identifying pain sensitivity in the clinic.

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bioRxiv2019

Unique Neurophysiological Vulnerability of Visual Attention Networks to Acute Inflammation

Illness is often accompanied by perceived cognitive sluggishness, a symptom that may stem from immune system activation. The current study used electroencephalography (EEG) to assess how inflammation affected three different distinct attentional processes: alerting, orienting and executive control. In a double-blinded placebo-controlled within-subjects design (20 healthy males, mean age = 24.5, SD = 3.4), Salmonella typhoid vaccination (0.025 mg; Typhim Vi, SanofiPasteur) was used to induce transient mild inflammation, while a saline injection served as a placebo-control. Participants completed the Attention Network Test with concurrent EEG recorded six hours post-injection. Analyses focused on behavioral task performance and on modulation of oscillatory EEG activity in the alpha band (9-12 Hz) for alerting as well as orienting attention and frontal theta band (4-8 Hz) for executive control. Vaccination induced mild systemic inflammation, as assessed by interleukin-6 (IL-6) levels. While no behavioral task performance differences between the inflammation and placebo condition were evident, inflammation caused significant alterations to task-related brain activity. Specifically, inflammation produced greater cue-induced suppression of alpha power in the alerting aspect of attention while individual variation in the inflammatory response was significantly correlated with the degree of alpha power suppression. Notably, inflammation did not affect orienting (i.e., alpha lateralization) or executive control (i.e., frontal theta activity). These results reveal a unique neurophysiological vulnerability to acute mild inflammation of the neural network that underpins attentional alerting functions. Observed in the absence of performance decrements, these novel findings suggest that acute inflammation requires individuals to exert greater cognitive effort when preparing for a task in order to maintain adequate behavioral performance.\n\nHighlights O_LITyphoid vaccination induced a transient mild inflammatory state\nC_LIO_LIMild inflammation alters neurophysiological process associated with attention\nC_LIO_LIMild inflammation selectively increased alerting-related alpha suppression while behavior was unaffected\nC_LIO_LIA greater inflammatory response was correlated with more alpha suppression\nC_LI

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bioRxiv2017

Alpha/beta power compresses time in sub-second temporal judgments

While the perception of time plays a crucial role in our day-to-day functioning, the underlying neural mechanism of time processing on short time scales (~1s) remains to be elucidated. Recently, the power of beta oscillations (~20 Hz) has been suggested to play an important role in temporal processing. However, the paradigms supporting this view have often had confounds of working memory, as well as motor preparation. In the current EEG study, we set out to investigate if power of oscillatory activity would be involved in time perception without an explicit working memory component or confound of a motor response. Participants indicated through a button press whether the time between a tone and a visual stimulus was 1 or 1.5s.Critically, we focused on the differences in oscillatory activity in the alpha (~10 Hz) and beta (~20 Hz) ranges preceding correct versus incorrect temporal judgments. Behaviourally, we found participants made more errors on the long (1.5s) than on the short (1s) interval. In addition, we found that participants were fastest to correctly respond to a long interval. The onset of the tone induced a suppression of alpha and beta activity over occipital and parietal electrodes. In the long estimation intervals, this suppression was greater for correct than incorrect estimations. Interestingly, alpha and beta suppression allowed us to predict whether participants would judge the long interval correctly. For the short interval trials we did not find a significant difference in alpha or beta band activity for the correct and incorrect judgments. Taken together, our behavioural and EEG results suggest a multifaceted role of alpha and beta activity in the temporal estimation of sub- and supra-second intervals, where power increases seem to lead to temporal compression. Higher alpha and beta power resulted in shorter temporal judgments for sub-second intervals.\n\nHighlightsO_LITemporal judgments without motor confounds were studied with EEG.\nC_LIO_LIAlpha/beta activity differences for correct and incorrect temporal judgments.\nC_LIO_LISub-second intervals were judged as short when alpha/beta power was higher.\nC_LI

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bioRxiv2017

Changes in alpha activity reveal that social opinion modulates attention allocation during face processing

AbstractParticipants performance differs when conducting a task in the presence of a secondary individual, moreover the opinion the participant has of this individual also plays a role. Using EEG, we investigated how previous interactions with, and evaluations of, an avatar in virtual reality subsequently influenced attentional allocation to the face of that avatar. We focused on changes in the alpha activity as an index of attentional allocation. We found that the onset of an avatars face whom the participant had developed a rapport with induced greater alpha suppression. This suggests greater attentional resources allocated to the interacted-with avatars. The evaluative ratings of the avatar induced a U-shaped change in alpha suppression, such that participants paid most attention when the avatar was rated as average. These results suggest that attentional allocation is thus an important element of how behaviour is altered in the presence of a secondary individual.

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bioRxiv2017

Binding language: Structuring sentences through precisely timed oscillatory mechanisms

Syntactic binding refers to combining words into larger structures. Using EEG, we investigated the neural processes involved in syntactic binding. Participants were auditorily presented two-word sentences (i.e. a pronoun and pseudoverb such as she dotches, for which syntactic binding can take place) and wordlists (i.e. two pseudoverbs such as pob dotches, for which no binding can occur). Comparing these two conditions, we targeted syntactic binding while minimizing contributions of semantic binding and of other cognitive processes such as working memory. We found a converging pattern of results using two distinct analysis approaches: one approach using frequency bands as defined in previous literature, and one data-driven approach in which we looked at the entire range of frequencies between 3-30 Hz without the constraints of pre-defined frequency bands. In the syntactic binding (relative to the wordlist) condition, a power increase was observed in the alpha and beta frequency range shortly preceding the presentation of the target word that requires binding, which was maximal over frontal-central electrodes. Our interpretation is that these signatures reflect that language comprehenders expect the need for binding to occur. Following the presentation of the target word in a syntactic binding context (relative to the wordlist condition), an increase in alpha power maximal over a left lateralized cluster of frontal-temporal electrodes was observed. We suggest that this alpha increase relates to syntactic binding taking place. Taken together, our findings suggest that increases in alpha and beta power are reflections of distinct the neural processes underlying syntactic binding.

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bioRxiv2017

Aberrant brain response after auditory deviance in PTSD compared to trauma controls: An EEG study.

Part of the symptomatology of post-traumatic stress disorder (PTSD) are alterations in arousal and reactivity which could be related to a maladaptive increase in the automated sensory change detection system of the brain. In the current EEG study we investigated whether the brains response to a simple auditory sensory change was altered in patients with PTSD relative to trauma-exposed matched controls who did not develop the disorder. Thirteen male PTSD patients and trauma-exposed controls matched for age and educational level were presented regular auditory pure tones (1000 Hz, 200 ms duration), with 11% of the tones deviating in both duration (50 ms) and frequency (1200 Hz) while watching a silent movie. Relative to the controls, patients who had developed PTSD showed enhanced mismatch negativity (MMN), increased theta power (5-7 Hz), and stronger suppression of upper alpha activity (13-15 Hz) after deviant vs. standard tones. Behaviourally, the alpha suppression in PTSD correlated with decreased spatial working memory performance suggesting it might reflect enhanced stimulus-feature representations in auditory memory. These results taken together suggest that PTSD patients and trauma-exposed controls can be distinguished by enhanced involuntary attention to changes in sensory patterns.

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bioRxiv2017

Expect to neglect: Cross-modal resource allocation in anticipation of visual load

Human information processing is limited in capacity. To prevent sensory overload, expectation of upcoming events has been suggested to allocate processing resources to task-relevant regions (e.g., visual system), at the expense of processing in task-irrelevant regions (e.g., auditory system). In support of this, for tasks involving a high visual perceptual load (e.g. visual target search within physically similar distractors), auditory evoked responses were found to be attenuated1. This EEG study aimed to further elucidate the neural mechanisms by which the brain prepares for sensory overload. We investigated how expectancy about visual load modulated neural activity, prior to the onset of visual stimuli. Visual load in a letter search task was manipulated by varying the target letters similarity to the remaining letters and the letter set size from which flankers were randomly drawn. Importantly, audio-visual cues signaled the likely visual load of the upcoming stimulus-array, manipulating expectancy about visual task load. Cues signaling high visual load elicited attenuated auditory-evoked responses and increased alpha activity over task-irrelevant (auditory) regions, suggesting a functional inhibition of those regions already prior to the arrival of the visual array to suppress auditory cue processing. We also observed a sustained posterior positivity in the ERPs after high perceptual load cues, whose amplitude correlated with reaction times, suggestive of resource allocation for the upcoming visual targets. Expectation about visual load may thus prepare the attentional system both by facilitating target processing and task execution and inhibiting irrelevant sensory processing, thus providing efficient means to overcome attentional limits in situations with complex visual input.

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