Spatial attention affects brain activity in human primary visual cortex

People are quicker to detect examples of real-world object categories in natural scenes than is predicted by classic attention theories. One explanation for this puzzle suggests that experience renders the visual system sensitive to midlevel features diagnosing target presence. These are detected without the need for spatial attention, much as occurs for targets defined by low-level features like color or orientation. The alternative is that naturalistic search relies on spatial attention but is highly efficient because global scene information can be used to quickly reject nontarget objects and locations. Here, we use ERPs to differentiate between these possibilities. Results show that hallmark evidence of ultrafast target detection in frontal brain activity is preceded by an index of spatially specific distractor suppression in visual cortex. Naturalistic search for heterogenous targets therefore appears to rely on spatial operations that act on neural object representations, as predicted by classic attention theory. People appear able to rapidly reject nontarget objects and locations, consistent with the idea that global scene information is used to constrain naturalistic search and increase search efficiency.

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The Temporal Dynamics of Object Processing in Visual Cortex during the Transition from Distributed to Focused Spatial Attention

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00045 ◽

2011 ◽

Vol 23 (12) ◽

pp. 4094-4105 ◽

Cited By ~ 2

Author(s):

Chien-Te Wu ◽

Melissa E. Libertus ◽

Karen L. Meyerhoff ◽

Marty G. Woldorff

Keyword(s):

Visual Cortex ◽

Spatial Attention ◽

Cognitive Neuroscience ◽

Visual Processing ◽

Object Representation ◽

Temporal Dynamics ◽

Brain Activity ◽

Object Processing ◽

Electrical Brain Activity

Several major cognitive neuroscience models have posited that focal spatial attention is required to integrate different features of an object to form a coherent perception of it within a complex visual scene. Although many behavioral studies have supported this view, some have suggested that complex perceptual discrimination can be performed even with substantially reduced focal spatial attention, calling into question the complexity of object representation that can be achieved without focused spatial attention. In the present study, we took a cognitive neuroscience approach to this problem by recording cognition-related brain activity both to help resolve the questions about the role of focal spatial attention in object categorization processes and to investigate the underlying neural mechanisms, focusing particularly on the temporal cascade of these attentional and perceptual processes in visual cortex. More specifically, we recorded electrical brain activity in humans engaged in a specially designed cued visual search paradigm to probe the object-related visual processing before and during the transition from distributed to focal spatial attention. The onset times of the color popout cueing information, indicating where within an object array the subject was to shift attention, was parametrically varied relative to the presentation of the array (i.e., either occurring simultaneously or being delayed by 50 or 100 msec). The electrophysiological results demonstrate that some levels of object-specific representation can be formed in parallel for multiple items across the visual field under spatially distributed attention, before focal spatial attention is allocated to any of them. The object discrimination process appears to be subsequently amplified as soon as focal spatial attention is directed to a specific location and object. This set of novel neurophysiological findings thus provides important new insights on fundamental issues that have been long-debated in cognitive neuroscience concerning both object-related processing and the role of attention.

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Consistent and precise localization of brain activity in human primary visual cortex by MEG and fMRI

NeuroImage ◽

10.1016/s1053-8119(02)00053-8 ◽

2003 ◽

Vol 18 (3) ◽

pp. 595-609 ◽

Cited By ~ 98

Author(s):

F. Moradi ◽

L.C. Liu ◽

K. Cheng ◽

R.A. Waggoner ◽

K. Tanaka ◽

...

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Brain Activity ◽

Precise Localization

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Retinotopic-like maps of spatial sound in primary ‘visual’ cortex of blind human echolocators

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2019.1910 ◽

2019 ◽

Vol 286 (1912) ◽

pp. 20191910 ◽

Cited By ~ 4

Author(s):

Liam J. Norman ◽

Lore Thaler

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Functional Organization ◽

Brain Activity ◽

Sensory Modality ◽

Spatial Sound ◽

Sensory Cortices ◽

Spatial Locations ◽

The Brain ◽

Rule Out

The functional specializations of cortical sensory areas were traditionally viewed as being tied to specific modalities. A radically different emerging view is that the brain is organized by task rather than sensory modality, but it has not yet been shown that this applies to primary sensory cortices. Here, we report such evidence by showing that primary ‘visual’ cortex can be adapted to map spatial locations of sound in blind humans who regularly perceive space through sound echoes. Specifically, we objectively quantify the similarity between measured stimulus maps for sound eccentricity and predicted stimulus maps for visual eccentricity in primary ‘visual’ cortex (using a probabilistic atlas based on cortical anatomy) to find that stimulus maps for sound in expert echolocators are directly comparable to those for vision in sighted people. Furthermore, the degree of this similarity is positively related with echolocation ability. We also rule out explanations based on top-down modulation of brain activity—e.g. through imagery. This result is clear evidence that task-specific organization can extend even to primary sensory cortices, and in this way is pivotal in our reinterpretation of the functional organization of the human brain.

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Synchronous SSVEP Data Acquisition System

Annales Universitatis Mariae Curie-Sklodowska sectio AI – Informatica ◽

10.2478/umcsinfo-2014-0018 ◽

2014 ◽

Vol 14 (3) ◽

Author(s):

Sławomir Kotyra ◽

Grzegorz M. Wójcik ◽

Marcin Smolira

Keyword(s):

Visual Cortex ◽

Steady State ◽

Data Acquisition ◽

Primary Visual Cortex ◽

Brain Activity ◽

Data Acquisition System ◽

Visually Evoked Potentials ◽

Light Stimulation ◽

Simple Method ◽

Stimulation Of

AbstractSteady State Visually Evoked Potentials have been known for several decades and they appear in the primary visual cortex of brain as a result of light stimulation of the sense of sight. In this article a simple method for electroencephalographic data acquisition is presented. The system is based on the DSM-51 unit connected to goggles with blinking diodes and Mindset-1000 EEG amplifier with 16 channels. We present self-developed hardware and method of effective synchronization for the light stimulation and brain activity recording.

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In vivo brain activity imaging of interactively locomoting mice

10.1101/203422 ◽

2017 ◽

Cited By ~ 1

Author(s):

Shigenori Inagaki ◽

Masakazu Agetsuma ◽

Shinya Ohara ◽

Toshio Iijima ◽

Tetsuichi Wazawa ◽

...

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Brain Activity ◽

Field Potential ◽

Brain Functions ◽

Wide Range ◽

Novel Method ◽

Freely Moving ◽

Voltage Indicator

AbstractElectrophysiological field potential dynamics have been widely used to investigate brain functions and related psychiatric disorders. Conversely, however, various technical limitations of conventional recording methods have limited its applicability to freely moving subjects, especially when they are in a group and socially interacting with each other. Here, we propose a new method to overcome these technical limitations by introducing a bioluminescent voltage indicator called LOTUS-V. Using our simple and fiber-free recording method, named “SNIPA,” we succeeded in capturing brain activity in freely-locomotive mice, without the need for complicated instruments. This novel method further allowed us to simultaneously record from multiple independently-locomotive animals that were interacting with one another. Further, we successfully demonstrated that the primary visual cortex was activated during the interaction. This methodology will further facilitate a wide range of studies in neurobiology and psychiatry.

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Sleep is more than rest for plasticity in the human cortex

SLEEP ◽

10.1093/sleep/zsaa216 ◽

2021 ◽

Author(s):

Christoph Nissen ◽

Hannah Piosczyk ◽

Johannes Holz ◽

Jonathan G Maier ◽

Lukas Frase ◽

...

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Neural Plasticity ◽

Discrimination Task ◽

Cortical Plasticity ◽

Brain Activity ◽

Nrem Sleep ◽

Human Cortex ◽

Healthy Humans ◽

Active Wakefulness

Abstract Sleep promotes adaptation of behavior and underlying neural plasticity in comparison to active wakefulness. However, the contribution of its two main characteristics, sleep-specific brain activity and reduced stimulus interference, remains unclear. We tested healthy humans on a texture discrimination task, a proxy for neural plasticity in primary visual cortex, in the morning and retested them in the afternoon after a period of daytime sleep, passive waking with maximally reduced interference, or active waking. Sleep restored performance in direct comparison to both passive and active waking, in which deterioration of performance across repeated within-day testing has been linked to synaptic saturation in the primary visual cortex. No difference between passive and active waking was observed. Control experiments indicated that deterioration across wakefulness was retinotopically specific to the trained visual field and not due to unspecific performance differences. The restorative effect of sleep correlated with time spent in NREM sleep and with electroencephalographic slow wave energy, which is thought to reflect renormalization of synaptic strength. The results indicate that sleep is more than a state of reduced stimulus interference, but that sleep-specific brain activity restores performance by actively refining cortical plasticity.

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Cortical Oscillatory Dysrhythmias in Visual Snow Syndrome: A MEG Study

10.1101/2021.05.17.444460 ◽

2021 ◽

Author(s):

Jenny L Hepschke ◽

Robert A Seymour ◽

Wei A He ◽

Andrew Etchell ◽

Paul F Sowman ◽

...

Keyword(s):

Visual Cortex ◽

Primary Visual Cortex ◽

Brain Activity ◽

Peak Frequency ◽

Alpha Phase ◽

Alpha Power ◽

Gamma Peak ◽

Gamma Power ◽

Early Visual Cortex ◽

Phase Amplitude

Visual Snow (VS) refers to the persistent visual experience of static in the whole visual field of both eyes. It is often reported by patients with migraine and co-occurs with conditions like tinnitus and tremor. The underlying pathophysiology of the condition is poorly understood. Previously we hypothesised, that VSS may be characterised by disruptions to rhythmical activity within the visual system. To test this, data from 18 patients diagnosed with visual snow syndrome (VSS), and 16 matched controls, were acquired using Magnetoencephalography (MEG). Participants were presented with visual grating stimuli, known to elicit decreases in alpha-band (8-13Hz) power and increases in gamma-band power (40-70Hz). Data were mapped to source-space using a beamformer. Across both groups, decreased alpha power and increased gamma power localised to early visual cortex. Data from primary visual cortex (V1) were compared between groups. No differences were found in either alpha or gamma peak frequency or the magnitude of alpha power, p>.05. However, compared with controls, our VSS cohort displayed significantly increased V1 gamma power, p=.035. This new electromagnetic finding concurs with previous fMRI and PET findings suggesting that in VSS, the visual cortex is hyper-excitable. The coupling of alpha-phase to gamma amplitude (i.e., phase-amplitude coupling, PAC) within V1 was also quantified. Compared with controls, the VSS group had significantly reduced alpha-gamma PAC, p<.05, indicating a potential excitation-inhibition imbalance in VSS, as well as a potential disruption to top-down 'noise-cancellation' mechanisms. Overall, these results suggest that rhythmical brain activity in primary visual cortex is both hyperexcitable and disorganised in VSS, consistent with visual snow being a condition of thalamocortical dysrhythmia.

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Alpha oscillations do not implement gain control in early visual cortex but rather gating in parieto-occipital regions

10.1101/2020.04.03.021485 ◽

2020 ◽

Author(s):

Alexander Zhigalov ◽

Ole Jensen

Keyword(s):

Visual Cortex ◽

Spatial Attention ◽

Neuronal Excitability ◽

Brain Activity ◽

Gain Control ◽

Alpha Power ◽

Alpha Band ◽

Alpha Oscillations ◽

Early Visual Cortex ◽

Broadband Frequency

AbstractSpatial attention provides a mechanism for respectively enhancing relevant and suppressing irrelevant information. While it is well-established that attention modulates oscillations in the alpha band, it remains unclear if alpha oscillations are involved in directly modulating the neuronal excitability associated with the allocation of spatial attention. In this study in humans, we utilized a novel broadband frequency (60 – 70 Hz) tagging paradigm to quantify neuronal excitability in relation to alpha oscillations in a spatial attention paradigm. We used magnetoencephalography to characterize ongoing brain activity as it allows for localizing the sources of both the alpha and frequency tagging responses. We found that attentional modulation of alpha power and the frequency tagging response are uncorrelated over trials. Importantly, the neuronal sources of the tagging response were localized in early visual cortex (V1) whereas the sources of the alpha activity were identified around parieto-occipital sulcus. Moreover, we found that attention did not modulate the latency of the frequency tagged responses. Our findings point to alpha band oscillations serving a downstream gating role rather than implementing gain control of excitability in early visual regions.Significance StatementBy combining magnetoencephalography and a novel broadband frequency tagging approach, we show that spatial attention differently modulates alpha oscillations and neuronal excitability. Importantly, the sources of the alpha oscillations and tagging responses were spatially distinct and the alpha power and tagging response were not related over trials. These results are inconsistent with previous ideas suggesting that alpha oscillations are involved in gain control of early sensory regions; rather alpha oscillations are involved in the allocation of neuronal resources in downstream regions.

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Spatial attention in area V4 is mediated by circuits in primary visual cortex

Neural Networks ◽

10.1016/j.neunet.2009.07.010 ◽

2009 ◽

Vol 22 (8) ◽

pp. 1039-1054 ◽

Cited By ~ 6

Author(s):

Paul H. Tiesinga ◽

Calin I. Buia

Keyword(s):

Visual Cortex ◽

Spatial Attention ◽

Primary Visual Cortex ◽

Area V4

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