A domain-general process for theta-rhythmic sampling of either environmental information or internally stored information.

Many everyday tasks, such as shopping for groceries, require the sampling of both environmental information and internally stored information. Selective attention involves the preferential processing and sampling of behaviorally important information from the external environment, while working memory involves the preferential processing and sampling of behaviorally important, internally stored information. These essential cognitive processes share neural resources within a large-scale network that includes frontal, parietal, and sensory cortices, and these shared neural resources can lead to between-domain interactions.

Differential neural mechanisms underlie cortical gating of visual spatial attention mediated by alpha-band oscillations.

Selective attention relies on neural mechanisms that facilitate processing of behaviorally relevant sensory information while suppressing irrelevant information, consistently linked to alpha-band oscillations in human M/EEG studies. We analyzed cortical alpha responses from intracranial electrodes implanted in eight epilepsy patients, who performed a visual spatial attention task. Electrocorticographic data revealed a spatiotemporal dissociation between attention-modulated alpha desynchronization, associated with the enhancement of sensory processing, and alpha synchronization, associated with the suppression of sensory processing, during the cue-target interval.

Separate Cue- and Alpha-Related Mechanisms for Distractor Suppression.

Research on selective attention has largely focused on the enhancement of behaviorally important information, with less focus on the suppression of distracting information. Enhancement and suppression can operate through a push-pull relationship attributable to competitive interactions among neural populations. There has been considerable debate, however, regarding (1) whether suppression can be voluntarily deployed, independent of enhancement, and (2) whether voluntary deployment of suppression is associated with neural processes occurring prior to the distractor onset.

Distractor suppression does and does not depend on pre-distractor alpha-band activity.

Unlabelled: Selective attention enhances behaviorally important information and suppresses distracting information. Research on the neural basis of selective attention has largely focused on sensory enhancement, with less focus on sensory suppression. Enhancement and suppression can operate through a push-pull relationship that arises from competitive interactions among neural populations.

Rhythmic temporal coordination of neural activity prevents representational conflict during working memory.

Selective attention is characterized by alternating states associated with either attentional sampling or attentional shifting, helping to prevent functional conflicts by isolating function-specific neural activity in time. We hypothesized that such rhythmic temporal coordination might also help to prevent representational conflicts during working memory. Multiple items can be simultaneously held in working memory, and these items can be represented by overlapping neural populations.

Interacting rhythms enhance sensitivity of target detection in a fronto-parietal computational model of visual attention.

Even during sustained attention, enhanced processing of attended stimuli waxes and wanes rhythmically, with periods of enhanced and relatively diminished visual processing (and subsequent target detection) alternating at 4 or 8 Hz in a sustained visual attention task. These alternating attentional states occur alongside alternating dynamical states, in which lateral intraparietal cortex (LIP), the frontal eye field (FEF), and the mediodorsal pulvinar (mdPul) exhibit different activity and functional connectivity at α, β, and γ frequencies-rhythms associated with visual processing, working memory, and motor suppression. To assess whether and how these multiple interacting rhythms contribute to periodicity in attention, we propose a detailed computational model of FEF and LIP.

There Is More Evidence of Rhythmic Attention than Can Be Found in Behavioral Studies: Perspective on Brookshire, 2022.

Recent research indicates periodicity in attention-related sampling and switching, with some of the initial findings coming from behavioral studies. Brookshire [Brookshire, G. Putative rhythms in attentional switching can be explained by aperiodic temporal structure.

Spike Timing in the Attention Network Predicts Behavioral Outcome Prior to Target Selection.

There has been little evidence linking changes in spiking activity that occur prior to a spatially predictable target (i.e., prior to target selection) to behavioral outcomes, despite such preparatory changes being widely assumed to enhance the sensitivity of sensory processing.

Dynamic pulvino-cortical interactions in the primate attention network.

While research in previous decades demonstrated a link between the pulvinar nucleus of the thalamus and visual selective attention, the pulvinar's specific functional role has remained elusive. However, methodological advances in electrophysiological recordings in non-human primates, including simultaneous recordings in multiple brain regions, have recently begun to reveal the pulvinar's functional contributions to selective attention. These new findings suggest that the pulvinar is critical for the efficient transmission of sensory information within and between cortical regions, both synchronizing cortical activity across brain regions and controlling cortical excitability.

Functional Specialization in the Attention Network.

Spatial attention is comprised of neural mechanisms that boost sensory processing at a behaviorally relevant location while filtering out competing information. The present review examines functional specialization in the network of brain regions that directs such preferential processing. This attention network includes both cortical (e.

The Puzzling Pulvinar.

The functional role of the pulvinar, with its widespread cortical connectivity, has remained elusive. In this issue of Neuron, Jaramillo et al. (2019) provide a computational roadmap for how the pulvinar might influence various cognitive behaviors across multiple large-scale networks.

The mediodorsal pulvinar coordinates the macaque fronto-parietal network during rhythmic spatial attention.

Spatial attention is discontinuous, sampling behaviorally relevant locations in theta-rhythmic cycles (3-6 Hz). Underlying this rhythmic sampling are intrinsic theta oscillations in frontal and parietal cortices that provide a clocking mechanism for two alternating attentional states that are associated with either engagement at the presently attended location (and enhanced perceptual sensitivity) or disengagement (and diminished perceptual sensitivity). It has remained unclear, however, how these theta-dependent states are coordinated across the large-scale network that directs spatial attention.

A Rhythmic Theory of Attention.

Recent evidence has demonstrated that environmental sampling is a fundamentally rhythmic process. Both perceptual sensitivity during covert spatial attention and the probability of overt exploratory movements are tethered to theta-band activity (3-8Hz) in the attention network. The fronto-parietal part of this network is positioned at the nexus of sensory and motor functions, directing two tightly coupled processes related to environmental exploration: preferential routing of sensory input and saccadic eye movements.

Neural Mechanisms of Sustained Attention Are Rhythmic.

Classic models of attention suggest that sustained neural firing constitutes a neural correlate of sustained attention. However, recent evidence indicates that behavioral performance fluctuates over time, exhibiting temporal dynamics that closely resemble the spectral features of ongoing, oscillatory brain activity. Therefore, it has been proposed that periodic neuronal excitability fluctuations might shape attentional allocation and overt behavior.

A Dynamic Interplay within the Frontoparietal Network Underlies Rhythmic Spatial Attention.

Classic studies of spatial attention assumed that its neural and behavioral effects were continuous over time. Recent behavioral studies have instead revealed that spatial attention leads to alternating periods of heightened or diminished perceptual sensitivity. Yet, the neural basis of these rhythmic fluctuations has remained largely unknown.

Neuro-oscillatory phase alignment drives speeded multisensory response times: an electro-corticographic investigation.

Even simple tasks rely on information exchange between functionally distinct and often relatively distant neuronal ensembles. Considerable work indicates oscillatory synchronization through phase alignment is a major agent of inter-regional communication. In the brain, different oscillatory phases correspond to low- and high-excitability states.

Rhythmic sampling within and between objects despite sustained attention at a cued location.

The brain directs its limited processing resources through various selection mechanisms, broadly referred to as attention. The present study investigated the temporal dynamics of two such selection mechanisms: space- and object-based selection. Previous evidence has demonstrated that preferential processing resulting from a spatial cue (i.

Auditory-driven phase reset in visual cortex: human electrocorticography reveals mechanisms of early multisensory integration.

Findings in animal models demonstrate that activity within hierarchically early sensory cortical regions can be modulated by cross-sensory inputs through resetting of the phase of ongoing intrinsic neural oscillations. Here, subdural recordings evaluated whether phase resetting by auditory inputs would impact multisensory integration processes in human visual cortex. Results clearly showed auditory-driven phase reset in visual cortices and, in some cases, frank auditory event-related potentials (ERP) were also observed over these regions.

Multisensory representation of frequency across audition and touch: high density electrical mapping reveals early sensory-perceptual coupling.

The frequency of environmental vibrations is sampled by two of the major sensory systems, audition and touch, notwithstanding that these signals are transduced through very different physical media and entirely separate sensory epithelia. Psychophysical studies have shown that manipulating frequency in audition or touch can have a significant cross-sensory impact on perceived frequency in the other sensory system, pointing to intimate links between these senses during computation of frequency. In this regard, the frequency of a vibratory event can be thought of as a multisensory perceptual construct.

Atypical category processing and hemispheric asymmetries in high-functioning children with autism: revealed through high-density EEG mapping.

Behavioral evidence for an impaired ability to group objects based on similar physical or semantic properties in autism spectrum disorders (ASD) has been mixed. Here, we recorded brain activity from high-functioning children with ASD as they completed a visual-target detection task. We then assessed the extent to which object-based selective attention automatically generalized from targets to non-target exemplars from the same well-known object class (e.

Pitting binding against selection--electrophysiological measures of feature-based attention are attenuated by Gestalt object grouping.

Humans have limited cognitive resources to process the nearly limitless information available in the environment. Endogenous, or 'top-down', selective attention to basic visual features such as color or motion is a common strategy for biasing resources in favor of the most relevant information sources in a given context. Opposing this top-down separation of features is a 'bottom-up' tendency to integrate, or bind, the various features that constitute objects.

Ready, set, reset: stimulus-locked periodicity in behavioral performance demonstrates the consequences of cross-sensory phase reset.

The simultaneous presentation of a stimulus in one sensory modality often enhances target detection in another sensory modality, but the neural mechanisms that govern these effects are still under investigation. Here, we test a hypothesis proposed in the neurophysiological literature: that auditory facilitation of visual-target detection operates through cross-sensory phase reset of ongoing neural oscillations (Lakatos et al., 2009).

Auditory facilitation of visual-target detection persists regardless of retinal eccentricity and despite wide audiovisual misalignments.

It is well established that sounds can enhance visual-target detection, but the mechanisms that govern these cross-sensory effects, as well as the neural pathways involved, are largely unknown. Here, we tested behavioral predictions stemming from the neurophysiologic and neuroanatomic literature. Participants detected near-threshold visual targets presented either at central fixation or peripheral to central fixation that were sometimes paired with sounds that originated from widely misaligned locations (up to 104° from the visual target).