scholarly journals Left-Hemispheric Asymmetry for Object-Based Attention: an ERP Study

2019 ◽  
Vol 9 (11) ◽  
pp. 315 ◽  
Author(s):  
Andrea Orlandi ◽  
Alice Mado Proverbio

It has been shown that selective attention enhances the activity in visual regions associated with stimulus processing. The left hemisphere seems to have a prominent role when non-spatial attention is directed towards specific stimulus features (e.g., color, spatial frequency). The present electrophysiological study investigated the time course and neural correlates of object-based attention, under the assumption of left-hemispheric asymmetry. Twenty-nine right-handed participants were presented with 3D graphic images representing the shapes of different object categories (wooden dummies, chairs, structures of cubes) which lacked detail. They were instructed to press a button in response to a target stimulus indicated at the beginning of each run. The perception of non-target stimuli elicited a larger anterior N2 component, which was likely associated with motor inhibition. Conversely, target selection resulted in an enhanced selection negativity (SN) response lateralized over the left occipito-temporal regions, followed by a larger centro-parietal P300 response. These potentials were interpreted as indexing attentional selection and categorization processes, respectively. The standardized weighted low-resolution electromagnetic tomography (swLORETA) source reconstruction showed the engagement of a fronto-temporo-limbic network underlying object-based visual attention. Overall, the SN scalp distribution and relative neural generators hinted at a left-hemispheric advantage for non-spatial object-based visual attention.

2010 ◽  
Vol 8 (6) ◽  
pp. 549-549
Author(s):  
L. Moya ◽  
S. Shomstein ◽  
A. Bagic ◽  
M. Behrmann

2009 ◽  
Vol 101 (2) ◽  
pp. 721-736 ◽  
Author(s):  
Tadashi Ogawa ◽  
Hidehiko Komatsu

During a visual search, information about the visual attributes of an object and associated behavioral requirements is essential for discriminating a target object from others in the visual field. On the other hand, information about the object's position appears to be more important when orienting the eyes toward the target. To understand the neural mechanisms underlying such a transition (i.e., from nonspatial- to spatial-based target selection), we examined the dependence of neuronal activity in the macaque posterior parietal cortex (PPC) on visual sensory properties and ongoing task demands. Monkeys were trained to perform a visual search task in which either a shape or color singleton within an array was the target, depending on the ongoing search dimension. The visual properties and the task demands were manipulated by independently changing the stimulus features (shape and color), singleton type, and search dimension. We found that a subset of PPC neurons significantly discriminated the target from other stimuli only when the target was defined by a particular stimulus dimension and had specific stimulus features, such as a shape-singleton, bar stimulus (condition-dependent target selection), whereas another subset did so irrespective of the stimulus features and the target-defining dimension (condition-independent target selection). There was thus a great deal of variety in the neural representations specifying the locus of the target. The coexistence of these distinctly different types of target-discrimination processes suggests that the PPC may be situated at the level where the transition from nonspatial- to spatial-based target selection takes place.


2013 ◽  
Author(s):  
Antonello Pellicano ◽  
Houpand Horoufchin ◽  
Harshal Patel ◽  
Iring Koch ◽  
Ferdinand Binkofski

2008 ◽  
Vol 12 (5) ◽  
pp. 182-186 ◽  
Author(s):  
Barbara G. Shinn-Cunningham

2021 ◽  
Author(s):  
Borja Rodriguez Herreros ◽  
Julia L Amengual ◽  
Jimena Lucrecia Vazquez-Anguiano ◽  
Silvio Ionta ◽  
Carlo Miniussi ◽  
...  

Converging evidence indicates that response inhibition may arise from the interaction of effortful proactive and reflexive reactive mechanisms. However, the distinction between the neural basis sustaining proactive and reactive inhibitory processes is still unclear. To identify reliable neural markers of proactive inhibition, we examined the behavioral and electrophysiological correlates elicited by manipulating the degree of inhibitory control in a task that involved the detection and amendment of errors. Restraining or encouraging the correction of errors did not affect the time course of the behavioral and neural correlates associated to reactive inhibition. We rather found that a bilateral and sustained decrease of corticomotor excitability was required for an effective proactive inhibitory control, whereas selective strategies were associated with defective response suppression. Our results provide behavioral and electrophysiological conclusive evidence of a comprehensive proactive inhibitory mechanism, with a distinctive underlying neural basis, governing the commission and amendment of errors. Together, these findings hint at a decisive role for changes in corticomotor excitability in determining whether an action will be successfully suppressed.


2017 ◽  
Vol 284 (1862) ◽  
pp. 20170969 ◽  
Author(s):  
Brandon Pratt ◽  
Tanvi Deora ◽  
Thomas Mohren ◽  
Thomas Daniel

Flying insects use feedback from various sensory modalities including vision and mechanosensation to navigate through their environment. The rapid speed of mechanosensory information acquisition and processing compensates for the slower processing times associated with vision, particularly under low light conditions. While halteres in dipteran species are well known to provide such information for flight control, less is understood about the mechanosensory roles of their evolutionary antecedent, wings. The features that wing mechanosensory neurons (campaniform sensilla) encode remains relatively unexplored. We hypothesized that the wing campaniform sensilla of the hawkmoth, Manduca sexta, rapidly and selectively extract mechanical stimulus features in a manner similar to halteres. We used electrophysiological and computational techniques to characterize the encoding properties of wing campaniform sensilla. To accomplish this, we developed a novel technique for localizing receptive fields using a focused IR laser that elicits changes in the neural activity of mechanoreceptors. We found that (i) most wing mechanosensors encoded mechanical stimulus features rapidly and precisely, (ii) they are selective for specific stimulus features, and (iii) there is diversity in the encoding properties of wing campaniform sensilla. We found that the encoding properties of wing campaniform sensilla are similar to those for haltere neurons. Therefore, it appears that the neural architecture that underlies the haltere sensory function is present in wings, which lends credence to the notion that wings themselves may serve a similar sensory function. Thus, wings may not only function as the primary actuator of the organism but also as sensors of the inertial dynamics of the animal.


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