scholarly journals Top-Down Beta Oscillatory Signaling Conveys Behavioral Context to Primary Visual Cortex

2016 ◽  
Author(s):  
Craig G. Richter ◽  
Richard Coppola ◽  
Steven L. Bressler
Keyword(s):  
Visual Cortex ◽  
Granger Causality ◽  
Frequency Band ◽  
Sensory Information ◽  
Task Demands ◽  
Behavioral Context ◽  
Global Knowledge ◽  
Top Down ◽  
Current Task ◽  
Beta Frequency

AbstractTop-down modulation of sensory processing is a critical neural mechanism subserving a number of important cognitive roles. Principally, top-down influences appear to inform lower-order sensory systems of the current ‘task at hand’, and thus may convey behavioral context to these systems. Accumulating evidence indicates that top-down cortical influences are carried by directed interareal synchronization of oscillatory neuronal populations. An important question currently under investigation by a number of laboratories is whether the information conveyed by directed interareal synchronization depends on the frequency band in which it is conveyed. Recent results point to the beta frequency band as being particularly important for conveying task-related information. However, little is known about the nature of the information conveyed by top-down directed influences. To investigate the information content of top-down directed beta-frequency influences, we measured spectral Granger Causality using local field potentials recorded from microelectrodes chronically implanted in visual cortical areas V1, V4, and TEO, and then applied multivariate pattern analysis to the spatial patterns of top-down spectral Granger Causality in the visual cortex. We decoded behavioral context by discriminating patterns of top-down (V4/TEO → V1) beta-peak spectral Granger Causality for two different task rules governing the correct responses to visual stimuli. The results indicate that top-down directed influences in visual cortex are carried by beta oscillations, and differentiate current task demands even before visual stimulus processing. They suggest that top-down beta-frequency oscillatory processes may coordinate the processing of sensory information by conveying global knowledge states to early levels of the sensory cortical hierarchy independently of bottom-up stimulus-driven processing.

scholarly journals Top-down control of visual cortex by the frontal eye fields through oscillatory realignment

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Domenica Veniero ◽  
Joachim Gross ◽  
Stephanie Morand ◽  
Felix Duecker ◽  
Alexander T. Sack ◽  
...  
Keyword(s):  
Visual Cortex ◽  
Transcranial Magnetic Stimulation ◽  
Visual Perception ◽  
Magnetic Stimulation ◽  
Single Pulse ◽  
Frontal Eye Fields ◽  
Phase Reset ◽  
Top Down ◽  
Visual Areas ◽  
Beta Frequency

AbstractVoluntary allocation of visual attention is controlled by top-down signals generated within the Frontal Eye Fields (FEFs) that can change the excitability of lower-level visual areas. However, the mechanism through which this control is achieved remains elusive. Here, we emulated the generation of an attentional signal using single-pulse transcranial magnetic stimulation to activate the FEFs and tracked its consequences over the visual cortex. First, we documented changes to brain oscillations using electroencephalography and found evidence for a phase reset over occipital sites at beta frequency. We then probed for perceptual consequences of this top-down triggered phase reset and assessed its anatomical specificity. We show that FEF activation leads to cyclic modulation of visual perception and extrastriate but not primary visual cortex excitability, again at beta frequency. We conclude that top-down signals originating in FEF causally shape visual cortex activity and perception through mechanisms of oscillatory realignment.

Frontal lobes and attention: Processes and networks, fractionation and integration

2006 ◽  
Vol 12 (2) ◽  
pp. 261-271 ◽  
Author(s):  
DONALD T. STUSS
Keyword(s):  
Frontal Lobes ◽  
Task Demands ◽  
Activation Process ◽  
Top Down ◽  
Supervisory System ◽  
Current Task ◽  
Frontal Processes ◽  
General Activation ◽  
Lesion Studies ◽  
The Brain

The frontal lobes (FL), are they a general adaptive global capacity processor, or a series of fractionated processes? Our lesion studies focusing on attention have demonstrated impairments in distinct processes due to pathology in different frontal regions, implying fractionation of the “supervisory system.” However, when task demands are manipulated, it becomes evident that the frontal lobes are not just a series of independent processes. Increased complexity of task demands elicits greater involvement of frontal regions along a fixed network related to a general activation process. For some task demands, one or more anatomically distinct frontal processes may be recruited. In other conditions, there is a bottom-up nonfrontal/frontal network, with impairment noted maximally for the lesser task demands in the nonfrontal automatic processing regions, and then as task demands change, increased involvement of different frontal (more “strategic”) regions, until it appears all frontal regions are involved. With other measures, the network is top-down, with impairment in the measure first noted in the frontal region and then, with changing task demands, involving a posterior region. Adaptability is not just a property of FL, it is the fluid recruitment of different processes anywhere in the brain as required by the current task. (JINS, 2006,12, 261–271.)

scholarly journals Distracted by previous reward: integrating selection history, current task demands and saliency in a computational model

2021 ◽  
Author(s):  
Neda Meibodi ◽  
Hossein Abbasi ◽  
Anna Schubö ◽  
Dominik Endres
Keyword(s):  
Reaction Time ◽  
Task Demands ◽  
Top Down ◽  
Data Set ◽  
Learning History ◽  
History Effects ◽  
Selection History ◽  
Priority Map ◽  
Current Task ◽  
Level Model

Attention can be biased by previous learning and experience. We present analgorithmic-level model of this bias in visual attention that predicts quantitatively howbottom-up, top-down and selection history compete to control attention. In the model,the output of saliency maps as bottom-up guidance interacts with a history map thatencodes learning effects and a top-down task control to prioritize visual features. Wetest the model on a reaction-time (RT) data set from the experiment presented in [1].The model accurately predicts parameters of reaction time distributions from anintegrated priority map that is comprised of an optimal, weighted combination ofseparate maps. Analysis of the weights confirms learning history effects on attentionguidance. The model is able to capture individual differences between participants.Moreover, we demonstrate that a model with a reduced set of maps performs worse,indicating that integrating history, saliency and task information are required for aquantitative description of human attention.

Attention

2017 ◽  
Author(s):  
Martin V. Butz ◽  
Esther F. Kutter
Keyword(s):  
Dynamic Control ◽  
Sensory Information ◽  
Control Process ◽  
Focus Of Attention ◽  
Generative Models ◽  
Top Down ◽  
Bottom Up ◽  
Current Task ◽  
Task Oriented ◽  
Selection Of

Cognition does not work without attention. Attention enables us to focus on particular tasks and particular aspects in the environment. Psychological insights show that attention exhibits bottom-up and top-down components. Attention is attracted from the bottom-up towards unusual, exceptional, and unexpected sensory information. Top-down attention, on the other hand, filters information dependent on the current task-oriented expectations, which depend on the available generative models. This computational interpretation enables the explanation of conjunctive and disjunctive search. Different models of attention emphasize the importance of the unfolding interaction processes and a processing bottleneck can be detected. As a result, attention can be viewed as a dynamic control process that unfolds in redundant, neural fields, in which the selection of one interpretation and thus the processing bottleneck is strongest at the current focus of attention. The actual focus of attention itself is determined by the current behavioral and cognitive goals.

Spatial Attentional Selection Modulates Early Visual Stimulus Processing Independently of Visual Alpha Modulations

2020 ◽  
Vol 30 (6) ◽  
pp. 3686-3703 ◽  
Author(s):  
C Gundlach ◽  
S Moratti ◽  
N Forschack ◽  
M M Müller
Keyword(s):  
Visual Cortex ◽  
Spatial Attention ◽  
Sensory Processing ◽  
Sensory Information ◽  
Gain Control ◽  
Relevant Information ◽  
Task Demands ◽  
Alpha Band ◽  
Stimulus Processing ◽  
Early Visual Cortex

Abstract The capacity-limited human brain is constantly confronted with a huge amount of sensory information. Selective attention is needed for biasing neural processing towards relevant information and consequently allows meaningful interaction with the environment. Activity in the alpha-band has been proposed to be related to top-down modulation of neural inhibition and could thus represent a viable candidate to control the priority of stimulus processing. It is, however, unknown whether modulations in the alpha-band directly relate to changes in the sensory gain control of the early visual cortex. Here, we used a spatial cueing paradigm while simultaneously measuring ongoing alpha-band oscillations and steady-state visual evoked potentials (SSVEPs) as a marker of continuous early sensory processing in the human visual cortex. Thereby, the effects of spatial attention for both of these signals and their potential interactions were assessed. As expected, spatial attention modulated both alpha-band and SSVEP responses. However, their modulations were independent of each other and the corresponding activity profiles differed across task demands. Thus, our results challenge the view that modulations of alpha-band activity represent a mechanism that directly alters or controls sensory gain. The potential role of alpha-band oscillations beyond sensory processing will be discussed in light of the present results.

scholarly journals Top-down working memory reorganization of the primary visual cortex: Granger Causality analysis

2017 ◽  
Vol 17 (10) ◽  
pp. 594 ◽  
Author(s):  
Lora Likova ◽  
Laura Cacciamani ◽  
Spero Nicholas ◽  
Kris Mineff
Keyword(s):  
Working Memory ◽  
Visual Cortex ◽  
Granger Causality ◽  
Primary Visual Cortex ◽  
Causality Analysis ◽  
Top Down ◽  
Granger Causality Analysis

scholarly journals Opposing influence of top-down and bottom-up input on different types of excitatory layer 2/3 neurons in mouse visual cortex

2020 ◽  
Author(s):  
Rebecca Jordan ◽  
Georg B. Keller
Keyword(s):  
Visual Cortex ◽  
Contextual Information ◽  
Sensory Information ◽  
Neuronal Responses ◽  
Cortical Circuits ◽  
Top Down ◽  
Bottom Up ◽  
Physiological Properties ◽  
Layer 2 ◽  
Mouse Visual Cortex

ABSTRACTProcessing in cortical circuits is driven by combinations of cortical and subcortical inputs. These signals are often conceptually categorized as bottom-up input, conveying sensory information, and top-down input, conveying contextual information. Using intracellular recordings in mouse visual cortex, we measured neuronal responses to visual input, locomotion, and visuomotor mismatches. We show that layer 2/3 (L2/3) neurons compute a difference between top-down motor-related input and bottom-up visual flow input. Most L2/3 neurons responded to visuomotor mismatch with either hyperpolarization or depolarization, and these two response types were associated with distinct physiological properties. Consistent with a subtraction of bottom-up and top-down input, visual and motor-related inputs had opposing influence in L2/3 neurons. In infragranular neurons, we found no evidence of a difference-computation and responses were consistent with a positive integration of visuomotor inputs. Our results provide evidence that L2/3 functions as a bidirectional comparator of top-down and bottom-up input.

scholarly journals Top-down beta oscillatory signaling conveys behavioral context in early visual cortex

2018 ◽  
Vol 8 (1) ◽  
Author(s):  
Craig G. Richter ◽  
Richard Coppola ◽  
Steven L. Bressler
Keyword(s):  
Visual Cortex ◽  
Behavioral Context ◽  
Top Down ◽  
Early Visual Cortex

scholarly journals Causal modulation of right hemisphere fronto-parietal phase synchrony with Transcranial Magnetic Stimulation during a conscious visual detection task

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Chloé Stengel ◽  
Marine Vernet ◽  
Julià L. Amengual ◽  
Antoni Valero-Cabré
Keyword(s):  
Transcranial Magnetic Stimulation ◽  
Visual Perception ◽  
Frequency Band ◽  
Magnetic Stimulation ◽  
Visual Detection ◽  
Detection Task ◽  
Oscillatory Activity ◽  
Top Down ◽  
The Right ◽  
High Beta

AbstractCorrelational evidence in non-human primates has reported increases of fronto-parietal high-beta (22–30 Hz) synchrony during the top-down allocation of visuo-spatial attention. But may inter-regional synchronization at this specific frequency band provide a causal mechanism by which top-down attentional processes facilitate conscious visual perception? To address this question, we analyzed electroencephalographic (EEG) signals from a group of healthy participants who performed a conscious visual detection task while we delivered brief (4 pulses) rhythmic (30 Hz) or random bursts of Transcranial Magnetic Stimulation (TMS) to the right Frontal Eye Field (FEF) prior to the onset of a lateralized target. We report increases of inter-regional synchronization in the high-beta band (25–35 Hz) between the electrode closest to the stimulated region (the right FEF) and right parietal EEG leads, and increases of local inter-trial coherence within the same frequency band over bilateral parietal EEG contacts, both driven by rhythmic but not random TMS patterns. Such increases were accompained by improvements of conscious visual sensitivity for left visual targets in the rhythmic but not the random TMS condition. These outcomes suggest that high-beta inter-regional synchrony can be modulated non-invasively and that high-beta oscillatory activity across the right dorsal fronto-parietal network may contribute to the facilitation of conscious visual perception. Our work supports future applications of non-invasive brain stimulation to restore impaired visually-guided behaviors by operating on top-down attentional modulatory mechanisms.

scholarly journals Causal Evidence for the Role of Neuronal Oscillations in Top–Down and Bottom–Up Attention

2019 ◽  
Vol 31 (5) ◽  
pp. 768-779 ◽  
Author(s):  
Justin Riddle ◽  
Kai Hwang ◽  
Dillan Cellier ◽  
Sofia Dhanani ◽  
Mark D'Esposito
Keyword(s):  
Visual Field ◽  
Conjunction Search ◽  
Intraparietal Sulcus ◽  
Top Down ◽  
Neuronal Oscillations ◽  
Bottom Up ◽  
Search Condition ◽  
Gamma Frequency ◽  
Task Conditions ◽  
Beta Frequency

Beta and gamma frequency neuronal oscillations have been implicated in top–down and bottom–up attention. In this study, we used rhythmic TMS to modulate ongoing beta and gamma frequency neuronal oscillations in frontal and parietal cortex while human participants performed a visual search task that manipulates bottom–up and top–down attention (single feature and conjunction search). Both task conditions will engage bottom–up attention processes, although the conjunction search condition will require more top–down attention. Gamma frequency TMS to superior precentral sulcus (sPCS) slowed saccadic RTs during both task conditions and induced a response bias to the contralateral visual field. In contrary, beta frequency TMS to sPCS and intraparietal sulcus decreased search accuracy only during the conjunction search condition that engaged more top–down attention. Furthermore, beta frequency TMS increased trial errors specifically when the target was in the ipsilateral visual field for the conjunction search condition. These results indicate that beta frequency TMS to sPCS and intraparietal sulcus disrupted top–down attention, whereas gamma frequency TMS to sPCS disrupted bottom–up, stimulus-driven attention processes. These findings provide causal evidence suggesting that beta and gamma oscillations have distinct functional roles for cognition.

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