Lateralized alpha activity and slow potentials shifts over visual cortex track the time course of both endogenous and exogenous orienting of attention

AbstractSpatial attention can be oriented endogenously, based on current task goals, or exogenously, triggered by salient events in the environment. Based upon literature demonstrating differences in the time course and neural substrates of each type of orienting, these two attention systems are often treated as fundamentally distinct. However, recent studies suggest that rhythmic neural activity in the alpha band (8-13Hz) and slow waves in the event-related potential (ERP) may emerge over parietal-occipital cortex following both endogenous and exogenous attention cues. To assess whether these neural changes index common processes of spatial attention, we conducted two within-subject experiments varying the two main dimensions over which endogenous and exogenous attention tasks typically differ: cue informativity (spatially predictive vs. non-predictive) and cue format (centrally vs. peripherally presented). This task design allowed us to tease apart neural changes related to top-down goals and those driven by the reflexive orienting of spatial attention, as well as examine their interactions in a novel hybrid cross-modal attention task. Our data demonstrate that both central and peripheral cues elicit lateralized ERPs over parietal-occipital cortex, though at different points in time, consistent with these ERPs reflecting the orienting of spatial attention. Lateralized alpha activity was also present across all tasks, emerging rapidly for peripheral cues and sustaining only for spatially informative cues. Overall, these data indicate that distinct slow-wave ERPs index the spatial orienting of endogenous and exogenous attention, while lateralized alpha activity represents a common signature of visual enhancement in anticipation of potential targets across both types of attention.

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Visual Spatial Attention in Migraine Sufferers in Postictal and Interictal Phases: An Event-Related Potential Study

Journal of Psychophysiology ◽

10.1027//0269-8803.15.1.22 ◽

2001 ◽

Vol 15 (1) ◽

pp. 22-34 ◽

Cited By ~ 2

Author(s):

D.H. de Koning ◽

J.C. Woestenburg ◽

M. Elton

Keyword(s):

Cerebral Cortex ◽

Visual Attention ◽

Migraine Attack ◽

Spatial Attention ◽

Event Related Potential ◽

Significant Enhancement ◽

Pathophysiological Mechanism ◽

Attention Task ◽

Visual Spatial Attention ◽

Visual Spatial

Migraineurs with and without aura (MWAs and MWOAs) as well as controls were measured twice with an interval of 7 days. The first session of recordings and tests for migraineurs was held about 7 hours after a migraine attack. We hypothesized that electrophysiological changes in the posterior cerebral cortex related to visual spatial attention are influenced by the level of arousal in migraineurs with aura, and that this varies over the course of time. ERPs related to the active visual attention task manifested significant differences between controls and both types of migraine sufferers for the N200, suggesting a common pathophysiological mechanism for migraineurs. Furthermore, migraineurs without aura (MWOAs) showed a significant enhancement for the N200 at the second session, indicating the relevance of time of measurement within migraine studies. Finally, migraineurs with aura (MWAs) showed significantly enhanced P240 and P300 components at central and parietal cortical sites compared to MWOAs and controls, which seemed to be maintained over both sessions and could be indicative of increased noradrenergic activity in MWAs.

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Interhemispheric EEG asymmetries during unilateral bright-light exposure and subsequent sleep in humans

AJP Regulatory Integrative and Comparative Physiology ◽

10.1152/ajpregu.00747.2007 ◽

2008 ◽

Vol 294 (3) ◽

pp. R1053-R1060 ◽

Cited By ~ 16

Author(s):

Christian Cajochen ◽

Rosalba Di Biase ◽

Makoto Imai

Keyword(s):

Visual Cortex ◽

Time Course ◽

Visual Stimulation ◽

Light Exposure ◽

Bright Light ◽

Occipital Cortex ◽

Alpha Activity ◽

Hemispheric Dominance ◽

Eeg Activity ◽

The Right

We tested whether evening exposure to unilateral photic stimulation has repercussions on interhemispheric EEG asymmetries during wakefulness and later sleep. Because light exerts an alerting response in humans, which correlates with a decrease in waking EEG theta/alpha-activity and a reduction in sleep EEG delta activity, we hypothesized that EEG activity in these frequency bands show interhemispheric asymmetries after unilateral bright light (1,500 lux) exposure. A 2-h hemi-field light exposure acutely suppressed occipital EEG alpha activity in the ipsilateral hemisphere activated by light. Subjects felt more alert during bright light than dim light, an effect that was significantly more pronounced during activation of the right than the left visual cortex. During subsequent sleep, occipital EEG activity in the delta and theta range was significantly reduced after activation of the right visual cortex but not after stimulation of the left visual cortex. Furthermore, hemivisual field light exposure was able to shift the left predominance in occipital spindle EEG activity toward the stimulated hemisphere. Time course analysis revealed that this spindle shift remained significant during the first two sleep cycles. Our results reflect rather a hemispheric asymmetry in the alerting action of light than a use-dependent recovery function of sleep in response to the visual stimulation during prior waking. However, the observed shift in the spindle hemispheric dominance in the occipital cortex may still represent subtle local use-dependent recovery functions during sleep in a frequency range different from the delta range.

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Form-From-Motion: MEG Evidence for Time Course and Processing Sequence

Journal of Cognitive Neuroscience ◽

10.1162/089892903321208105 ◽

2003 ◽

Vol 15 (2) ◽

pp. 157-172 ◽

Cited By ~ 30

Author(s):

M. A. Schoenfeld ◽

M. Woldorff ◽

E. Düzel ◽

H. Scheich ◽

H.-J. Heinze ◽

...

Keyword(s):

Spatial Attention ◽

Time Course ◽

Temporal Cortex ◽

Occipital Cortex ◽

Inferior Temporal Cortex ◽

Cortical Region ◽

Motion Cues ◽

Form Analysis ◽

Msec Delay ◽

Visual Cortical

The neural mechanisms and role of attention in the processing of visual form defined by luminance or motion cues were studied using magnetoencephalography. Subjects viewed bilateral stimuli composed of moving random dots and were instructed to covertly attend to either left or right hemifield stimuli in order to detect designated target stimuli that required a response. To generate form-from-motion (FFMo) stimuli, a subset of the dots could begin to move coherently to create the appearance of a simple form (e.g., square). In other blocks, to generate form-from-luminance (FFLu) stimuli that served as a control, a gray stimulus was presented superimposed on the randomly moving dots. Neuromagnetic responses were observed to both the FFLu and FFMo stimuli and localized to multiple visual cortical stages of analysis. Early activity in low-level visual cortical areas (striate/early extrastriate) did not differ for FFLu versus FFMo stimuli, nor as a function of spatial attention. Longer latency responses elicited by the FFLu stimuli were localized to the ventral-lateral occipital cortex (LO) and the inferior temporal cortex (IT). The FFMo stimuli also generated activity in the LO and IT, but only after first eliciting activity in the lateral occipital cortical region corresponding to MT/V5, resulting in a 50–60 msec delay in activity. All of these late responses (MT/V5, LO, and IT) were significantly modulated by spatial attention, being greatly attenuated for ignored FFLu and FFMo stimuli. These findings argue that processing of form in IT that is defined by motion requires a serial processing of information, first in the motion analysis pathway from V1 to MT/V5 and thereafter via the form analysis stream in the ventral visual pathway to IT.

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Spatial distance of target locations affects the time course of both endogenous and exogenous attentional deployment.

10.31234/osf.io/8cw6u ◽

2020 ◽

Author(s):

Frederik Geweke ◽

Emilia Pokta ◽

Viola S. Störmer

Keyword(s):

Time Course ◽

Temporal Dynamics ◽

Spatial Distance ◽

Exogenous Attention ◽

Endogenous Attention ◽

Attentional Deployment ◽

Current Task ◽

Time Courses ◽

Task Goals ◽

Target Locations

Spatial attention can be deployed exogenously, based on salient events in the environment, or endogenously, based on current task goals. Numerous studies have compared the time courses of these two types of attention, and have demonstrated that exogenous attention is fast and transient and endogenous attention is relatively slow but sustained. In the present study we investigated whether and how the temporal dynamics of exogenous and endogenous attention differ in terms of where attention is deployed in the visual field, in particular at locations nearby or far from fixation. Across a series experiments, we measured attentional shift times for each type of attention, and found overall slower deployment of endogenous relative to exogenous attention, in line with previous research. Importantly, we also consistently found that it takes longer to deploy attention at more distant locations relative to nearby locations, regardless of how attention was instigated. Overall, our results suggest that the temporal limits of attentional deployment across different spatial distances are similar for exogenous and endogenous attention, pointing to shared constraints underlying both attentional modes.

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Functionally independent components of early event-related potentials in a visual spatial attention task

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.1999.0469 ◽

1999 ◽

Vol 354 (1387) ◽

pp. 1135-1144 ◽

Cited By ~ 60

Author(s):

Scott Makeig ◽

Marissa Westerfield ◽

Jeanne Townsend ◽

Tzyy-Ping Jung ◽

Eric Courchesne ◽

...

Keyword(s):

Visual Field ◽

Spatial Attention ◽

Visual Target ◽

Event Related Potentials ◽

Event Related Potential ◽

Right Visual Field ◽

Early Event ◽

Attention Task ◽

Visual Spatial ◽

Related Potentials

Spatial visual attention modulates the first negative–going deflection in the human averaged event–related potential (ERP) in response to visual target and non–target stimuli (the N1 complex). Here we demonstrate a decomposition of N1 into functionally independent subcomponents with functionally distinct relations to task and stimulus conditions. ERPs were collected from 20 subjects in response to visual target and non–target stimuli presented at five attended and non–attended screen locations. Independent component analysis, a new method for blind source separation, was trained simultaneously on 500 ms grand average responses from all 25 stimulus–attention conditions and decomposed the non–target N1 complexes into five spatially fixed, temporally independent and physiologically plausible components. Activity of an early, laterally symmetrical component pair (N1a R and N1a L ) was evoked by the left and right visual field stimuli, respectively. Component N1a R peaked ca. 9 ms earlier than N1a L . Central stimuli evoked both components with the same peak latency difference, producing a bilateral scalp distribution. The amplitudes of these components were not reliably augmented by spatial attention. Stimuli in the right visual field evoked activity in a spatio–temporally overlapping bilateral component (N1b) that peaked at ca. 180 ms and was strongly enhanced by attention. Stimuli presented at unattended locations evoked a fourth component (P2a) peaking near 240 ms. A fifth component (P3f) was evoked only by targets presented in either visual field. The distinct response patterns of these components across the array of stimulus and attention conditions suggest that they reflect activity in functionally independent brain systems involved in processing attended and unattended visuospatial events.

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Short-term audiovisual spatial training enhances electrophysiological correlates of auditory selective spatial attention

10.1101/2020.12.23.424131 ◽

2020 ◽

Author(s):

Christina Hanenberg ◽

Michael-Christian Schlüter ◽

Stephan Getzmann ◽

Jörg Lewald

Keyword(s):

Spatial Attention ◽

Visual Feedback ◽

Visual Stimuli ◽

Event Related Potential ◽

Auditory Target ◽

Short Time Scale ◽

Cocktail Party ◽

Short Term ◽

Attention Task ◽

Electrical Imaging

AbstractAudiovisual cross-modal training has been proposed as a tool to improve human spatial hearing. Here, we investigated training-induced modulations of auditory-evoked event-related potential (ERP) components that have been associated with processes of auditory selective spatial attention when a speaker of interest has to be localized in a multiple speaker (“cocktail-party”) scenario. Forty-five healthy subjects were tested, including younger (19-29 yrs; n = 21) and older (66-76 yrs; n = 24) age groups. Three conditions of short-term training (duration 15 minutes) were compared, requiring localization of non-speech targets under “cocktail-party” conditions with either (1) synchronous presentation of co-localized auditory-target and visual stimuli (audiovisual-congruency training) or (2) immediate visual feedback on correct or incorrect localization responses (visual-feedback training), or (3) presentation of spatially incongruent auditory-target and visual stimuli presented at random positions with synchronous onset (control condition). Prior to and after training, subjects were tested in an auditory spatial attention task (15 minutes), requiring localization of a predefined spoken word out of three distractor words, which were presented with synchronous stimulus onset from different positions. Peaks of ERP components were analyzed with a specific focus on the N2, which is known to be a correlate of auditory selective spatial attention. N2 amplitudes were significantly larger after audiovisual-congruency training compared with the remaining training conditions for younger, but not older, subjects. Also, at the time of the N2, electrical imaging revealed an enhancement of electrical activity induced by audiovisual-congruency training in dorsolateral prefrontal cortex (Brodmann area 9) for the younger group. These findings suggest that cross-modal processes induced by audiovisual-congruency training under “cocktail-party” conditions at a short time scale resulted in an enhancement of correlates of auditory selective spatial attention.

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Hemispheric asymmetry of globus pallidus relates to alpha modulation in reward-related attentional tasks

10.1101/303016 ◽

2018 ◽

Author(s):

C. Mazzetti ◽

T. Staudigl ◽

T. R. Marshall ◽

J. M. Zumer ◽

S. J. Fallon ◽

...

Keyword(s):

Spatial Attention ◽

Globus Pallidus ◽

Alpha Activity ◽

Hemispheric Lateralization ◽

Monetary Reward ◽

Alpha Power ◽

Alpha Band ◽

Subcortical Structures ◽

Attention Task ◽

Subcortical Regions

AbstractWhile subcortical structures like the basal ganglia have been widely explored in relation to motor control, recent evidence suggests that their mechanisms extend to the domain of attentional switching. We here investigated the subcortical involvement in reward related top-down control of visual alpha-band oscillations (8 – 13 Hz), which have been consistently linked to mechanisms supporting the allocation of visuo-spatial attention. Given that items associated with contextual saliency (e.g. monetary reward or loss) attract attention, it is not surprising that the acquired salience of visual items further modulates. The executive networks controlling such reward-dependent modulations of oscillatory brain activity have yet to be fully elucidated. Although such networks have been explored in terms of cortico-cortical interactions, subcortical regions are likely to be involved. To uncover this, we combined MRI and MEG data from 17 male and 11 female participants, investigating whether derived measures of subcortical structural asymmetries predict interhemispheric modulation of alpha power during a spatial attention task. We show that volumetric hemispheric lateralization of globus pallidus (GP) and thalamus (Th) explains individual hemispheric biases in the ability to modulate posterior alpha power. Importantly, for the GP, this effect became stronger when the value-saliency parings in the task increased. Our findings suggest that the GP and Th in humans are part of a subcortical executive control network, differentially involved in modulating posterior alpha activity in the presence of saliency. Further investigation aimed at uncovering the interaction between subcortical and neocortical attentional networks would provide useful insight in future studies.Significance statementWhile the involvement of subcortical regions into higher level cognitive processing, such as attention and reward attribution, has been already indicated in previous studies, little is known about its relationship with the functional oscillatory underpinnings of said processes. In particular, interhemispheric modulation of alpha band (8-13Hz) oscillations, as recorded with magnetoencephalography (MEG), has been previously shown to vary as a function of salience (i.e. monetary reward/loss) in a spatial attention task. We here provide novel insights into the link between subcortical and cortical control of visual attention. Using the same reward-related spatial attention paradigm, we show that the volumetric lateralization of subcortical structures (specifically Globus Pallidus and Thalamus) explains individual biases in the modulation of visual alpha activity.

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Electrophysiological impact of multiple concussions in asymptomatic athletes: A re-analysis based on alpha activity during a visual-spatial attention task

Neuropsychologia ◽

10.1016/j.neuropsychologia.2017.11.022 ◽

2018 ◽

Vol 108 ◽

pp. 42-49 ◽

Cited By ~ 6

Author(s):

Samuel Guay ◽

Louis De Beaumont ◽

Brandi Lee Drisdelle ◽

Jean-Marc Lina ◽

Pierre Jolicoeur

Keyword(s):

Spatial Attention ◽

Alpha Activity ◽

Attention Task ◽

Visual Spatial Attention ◽

Visual Spatial

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Frontoparietal Control of Spatial Attention and Motor Intention in Human EEG

Journal of Neurophysiology ◽

10.1152/jn.01052.2004 ◽

2005 ◽

Vol 94 (1) ◽

pp. 764-774 ◽

Cited By ~ 99

Author(s):

Peter Praamstra ◽

Luc Boutsen ◽

Glyn W. Humphreys

Keyword(s):

Spatial Attention ◽

Time Course ◽

Response Selection ◽

Occipital Cortex ◽

Directional Information ◽

Attention Network ◽

Human Eeg ◽

Frontoparietal Network ◽

Motor Intention ◽

And Function

Relations between spatial attention and motor intention were investigated by means of an EEG potential elicited by shifting attention to a location in space as well as by the selection of a hand for responding. High-density recordings traced this potential to a common frontoparietal network activated by attentional orienting and by response selection. Within this network, parietal and frontal cortex were activated sequentially, followed by an anterior-to-posterior migration of activity culminating in the lateral occipital cortex. Based on temporal and polarity information provided by EEG, we hypothesize that the frontoparietal activation, evoked by directional information, updates a task-defined preparatory state by deselecting or inhibiting the behavioral option competing with the cued response side or the cued direction of attention. These results from human EEG demonstrate a direct EEG manifestation of the frontoparietal attention network previously identified in functional imaging. EEG reveals the time-course of activation within this network and elucidates the generation and function of associated directing-attention EEG potentials. The results emphasize transient activation and a decision-related function of the frontoparietal attention network, contrasting with the sustained preparatory activation that is commonly inferred from neuroimaging.

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