Articles de revues : « Ventral attention network »

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Scalf, Paige E., JeeWon Ahn, Diane M. Beck et Alejandro Lleras. « Trial History Effects in the Ventral Attentional Network ». Journal of Cognitive Neuroscience 26, n^o 12 (décembre 2014) : 2789–97. http://dx.doi.org/10.1162/jocn_a_00678.

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The ventral attentional network (VAN) is thought to drive “stimulus driven attention” [e.g., Asplund, C. L., Todd, J. J., Snyder, A. P., & Marois, R. A central role for the lateral prefrontal cortex in goal-directed and stimulus-driven attention. Nature Neuroscience, 13, 507–512, 2010; Shulman, G. L., McAvoy, M. P., Cowan, M. C., Astafiev, S. V., Tansy, A. P., D' Avossa, G., et al. Quantitative analysis of attention and detection signals during visual search. Journal of Neurophysiology, 90, 3384–3397, 2003]; in other words, it instantiates within the current stimulus environment the top–down attentional biases maintained by the dorsal attention network [e.g., Kincade, J. M., Abrams, R. A., Astafiev, S. V., Shulman, G. L., & Corbetta, M. An event-related functional magnetic resonance imaging study of voluntary and stimulus-driven orienting of attention. The Journal of Neuroscience: The Official Journal of the Society for Neuroscience, 25, 4593–4604, 2005]. Previous work has shown that the dorsal attentional network is sensitive to trial history, such that it is challenged by changes in task goals and facilitated by repetition thereof [e.g., Kristjánsson, A., Vuilleumier, P., Schwartz, S., Macaluso, E., & Driver, J. Neural basis for priming of pop-out during visual search revealed with fMRI. Cerebral Cortex, 17, 1612–1624, 2007]. Here, we investigate whether the VAN also preserves information across trials such that it is challenged when previously rejected stimuli become task relevant. We used fMRI to investigate the sensitivity of the ventral attentional system to prior history effects as measured by the distractor preview effect. This behavioral phenomenon reflects a bias against stimuli that have historically not supported task performance. We found regions traditionally considered to be part of the VAN (right middle frontal gyrus, inferior frontal gyrus and right supramarginal gyrus) [Shulman, G. L., McAvoy, M. P., Cowan, M. C., Astafiev, S. V., Tansy, A. P., D' Avossa, G., et al. Quantitative analysis of attention and detection signals during visual search. Journal of Neurophysiology, 90, 3384–3397, 2003] to be more active when task-relevant stimuli had not supported task performance in a previous trial than when they had. Investigations of the ventral visual system suggest that this effect is more reliably driven by trial history preserved within the VAN than that preserved within the visual system per se. We conclude that VAN maintains its interactions with top–down stimulus biases and bottom–up stimulation across time, allowing previous experience with the stimulus environment to influence attentional biases under current circumstances.

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Hsu, Howard Muchen, Zai-Fu Yao, Kai Hwang et Shulan Hsieh. « Between-module functional connectivity of the salient ventral attention network and dorsal attention network is associated with motor inhibition ». PLOS ONE 15, n^o 12 (3 décembre 2020) : e0242985. http://dx.doi.org/10.1371/journal.pone.0242985.

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The ability to inhibit motor response is crucial for daily activities. However, whether brain networks connecting spatially distinct brain regions can explain individual differences in motor inhibition is not known. Therefore, we took a graph-theoretic perspective to examine the relationship between the properties of topological organization in functional brain networks and motor inhibition. We analyzed data from 141 healthy adults aged 20 to 78, who underwent resting-state functional magnetic resonance imaging and performed a stop-signal task along with neuropsychological assessments outside the scanner. The graph-theoretic properties of 17 functional brain networks were estimated, including within-network connectivity and between-network connectivity. We employed multiple linear regression to examine how these graph-theoretical properties were associated with motor inhibition. The results showed that between-network connectivity of the salient ventral attention network and dorsal attention network explained the highest and second highest variance of individual differences in motor inhibition. In addition, we also found those two networks span over brain regions in the frontal-cingulate-parietal network, suggesting that these network interactions are also important to motor inhibition.

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Allan, Parker G., Robert G. Briggs, Andrew K. Conner, Christen M. O'Neal, Phillip A. Bonney, B. David Maxwell, Cordell M. Baker et al. « Parcellation-based tractographic modeling of the ventral attention network ». Journal of the Neurological Sciences 408 (janvier 2020) : 116548. http://dx.doi.org/10.1016/j.jns.2019.116548.

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Wang, Chenhao, Ju Lynn Ong, Amiya Patanaik, Juan Zhou et Michael W. L. Chee. « Spontaneous eyelid closures link vigilance fluctuation with fMRI dynamic connectivity states ». Proceedings of the National Academy of Sciences 113, n^o 34 (10 août 2016) : 9653–58. http://dx.doi.org/10.1073/pnas.1523980113.

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Fluctuations in resting-state functional connectivity occur but their behavioral significance remains unclear, largely because correlating behavioral state with dynamic functional connectivity states (DCS) engages probes that disrupt the very behavioral state we seek to observe. Observing spontaneous eyelid closures following sleep deprivation permits nonintrusive arousal monitoring. During periods of low arousal dominated by eyelid closures, sliding-window correlation analysis uncovered a DCS associated with reduced within-network functional connectivity of default mode and dorsal/ventral attention networks, as well as reduced anticorrelation between these networks. Conversely, during periods when participants’ eyelids were wide open, a second DCS was associated with less decoupling between the visual network and higher-order cognitive networks that included dorsal/ventral attention and default mode networks. In subcortical structures, eyelid closures were associated with increased connectivity between the striatum and thalamus with the ventral attention network, and greater anticorrelation with the dorsal attention network. When applied to task-based fMRI data, these two DCS predicted interindividual differences in frequency of behavioral lapsing and intraindividual temporal fluctuations in response speed. These findings with participants who underwent a night of total sleep deprivation were replicated in an independent dataset involving partially sleep-deprived participants. Fluctuations in functional connectivity thus appear to be clearly associated with changes in arousal.

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Sassenhagen, Jona, et Ina Bornkessel-Schlesewsky. « The P600 as a correlate of ventral attention network reorientation ». Cortex 66 (mai 2015) : A3—A20. http://dx.doi.org/10.1016/j.cortex.2014.12.019.

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Kucyi, Aaron, Mojgan Hodaie et Karen D. Davis. « Lateralization in intrinsic functional connectivity of the temporoparietal junction with salience- and attention-related brain networks ». Journal of Neurophysiology 108, n^o 12 (15 décembre 2012) : 3382–92. http://dx.doi.org/10.1152/jn.00674.2012.

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Neuroimaging studies have demonstrated that the right temporoparietal junction (TPJ) is activated during detection of salient stimuli, including pain, in the sensory environment. Right TPJ damage more often produces spatial neglect than left TPJ damage. We recently reported a right lateralized system of white matter connectivity of the TPJ. However, lateralization in intrinsic TPJ functional connectivity during a task/stimuli-independent state has not been fully characterized. Here we used resting-state functional MRI in healthy humans to compare the functional connectivity of right and left TPJ with salience- and attention-related brain networks. Independent components analysis revealed that both right and left TPJ were functionally connected with a network that included the anterior insula, dorsolateral prefrontal cortex (PFC), and mid-cingulate cortex, considered to be the salience/ventral attention network. Dual regression revealed this network was more strongly connected with right TPJ than left TPJ. Seed-based functional connectivity analysis showed 1) negative connectivity the TPJ bilaterally with the “default mode network”; 2) positive connectivity of TPJ bilaterally with the salience/ventral attention network; 3) stronger connectivity between right TPJ compared with left TPJ with regions within the salience/ventral attention network and mid-insula, S2, and temporal/parietal opercula (implicated in pain); and 4) stronger connectivity of left TPJ compared with right TPJ with the “executive control network,” including the dorsomedial/medial PFC, inferior frontal gyrus, and cerebellum (crus I/II). Our findings build on classic lesion and neuroimaging studies, demonstrating a complex spatial network organization of lateralization in TPJ functional connectivity in the absence of an overt stimulus.

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Westfall, Daniel R., Sheeba A. Anteraper, Laura Chaddock-Heyman, Eric S. Drollette, Lauren B. Raine, Susan Whitfield-Gabrieli, Arthur F. Kramer et Charles H. Hillman. « Resting-State Functional Connectivity and Scholastic Performance in Preadolescent Children : A Data-Driven Multivoxel Pattern Analysis (MVPA) ». Journal of Clinical Medicine 9, n^o 10 (2 octobre 2020) : 3198. http://dx.doi.org/10.3390/jcm9103198.

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Scholastic performance is the key metric by which schools measure student’s academic success, and it is important to understand the neural-correlates associated with greater scholastic performance. This study examines resting-state functional connectivity (RsFc) associated with scholastic performance (reading and mathematics) in preadolescent children (7–9 years) using an unbiased whole-brain connectome-wide multi-voxel pattern analysis (MVPA). MVPA revealed four clusters associated with reading composite score, these clusters were then used for whole-brain seed-based RsFc analysis. However, no such clusters were found for mathematics composite score. Post hoc analysis found robust associations between reading and RsFc dynamics with areas involved with the somatomotor, dorsal attention, ventral attention, limbic, frontoparietal, and default mode networks. These findings indicate that reading ability may be associated with a wide range of RsFc networks. Of particular interest, anticorrelations were observed between the default mode network and the somatomotor, dorsal attention, ventral attention, and frontoparietal networks. Previous research has demonstrated the importance of anticorrelations between the default mode network and frontoparietal network associated with cognition. These results extend the current literature exploring the role of network connectivity in scholastic performance of children.

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Devaney, Kathryn, Emily Levin, Vaibhav Tripathi, James Higgins, Sara Lazar et David Somers. « Attention and Default Mode Network Assessments of Meditation Experience during Active Cognition and Rest ». Brain Sciences 11, n^o 5 (29 avril 2021) : 566. http://dx.doi.org/10.3390/brainsci11050566.

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Meditation experience has previously been shown to improve performance on behavioral assessments of attention, but the neural bases of this improvement are unknown. Two prominent, strongly competing networks exist in the human cortex: a dorsal attention network, that is activated during focused attention, and a default mode network, that is suppressed during attentionally demanding tasks. Prior studies suggest that strong anti-correlations between these networks indicate good brain health. In addition, a third network, a ventral attention network, serves as a “circuit-breaker” that transiently disrupts and redirects focused attention to permit salient stimuli to capture attention. Here, we used functional magnetic resonance imaging to contrast cortical network activation between experienced focused attention Vipassana meditators and matched controls. Participants performed two attention tasks during scanning: a sustained attention task and an attention-capture task. Meditators demonstrated increased magnitude of differential activation in the dorsal attention vs. default mode network in a sustained attention task, relative to controls. In contrast, there were no evident attention network differences between meditators and controls in an attentional reorienting paradigm. A resting state functional connectivity analysis revealed a greater magnitude of anticorrelation between dorsal attention and default mode networks in the meditators as compared to both our local control group and a n = 168 Human Connectome Project dataset. These results demonstrate, with both task- and rest-based fMRI data, increased stability in sustained attention processes without an associated attentional capture cost in meditators. Task and resting-state results, which revealed stronger anticorrelations between dorsal attention and default mode networks in experienced mediators than in controls, are consistent with a brain health benefit of long-term meditation practice.

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Smucny, Jason, Ann Olincy et Jason R. Tregellas. « Nicotine restores functional connectivity of the ventral attention network in schizophrenia ». Neuropharmacology 108 (septembre 2016) : 144–51. http://dx.doi.org/10.1016/j.neuropharm.2016.04.015.

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Liu, Jie, Pengfei Xu, Jingyuan Zhang, Nengzhi Jiang, Xinying Li et Yuejia Luo. « Ventral attention-network effective connectivity predicts individual differences in adolescent depression ». Journal of Affective Disorders 252 (juin 2019) : 55–59. http://dx.doi.org/10.1016/j.jad.2019.04.033.

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Callejas, Alicia, Gordon L. Shulman et Maurizio Corbetta. « Dorsal and Ventral Attention Systems Underlie Social and Symbolic Cueing ». Journal of Cognitive Neuroscience 26, n^o 1 (janvier 2014) : 63–80. http://dx.doi.org/10.1162/jocn_a_00461.

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Eye gaze is a powerful cue for orienting attention in space. Studies examining whether gaze and symbolic cues recruit the same neural mechanisms have found mixed results. We tested whether there is a specialized attentional mechanism for social cues. We separately measured BOLD activity during orienting and reorienting attention following predictive gaze and symbolic cues. Results showed that gaze and symbolic cues exerted their influence through the same neural networks but also produced some differential modulations. Dorsal frontoparietal regions in left intraparietal sulcus (IPS) and bilateral MT+/lateral occipital cortex only showed orienting effects for symbolic cues, whereas right posterior IPS showed larger validity effects following gaze cues. Both exceptions may reflect the greater automaticity of gaze cues: Symbolic orienting may require more effort, while disengaging attention during reorienting may be more difficult following gaze cues. Face-selective regions, identified with a face localizer, showed selective activations for gaze cues reflecting sensory processing but no attentional modulations. Therefore, no evidence was found linking face-selective regions to a hypothetical, specialized mechanism for orienting attention to gaze cues. However, a functional connectivity analysis showed greater connectivity between face-selective regions and right posterior IPS, posterior STS, and inferior frontal gyrus during gaze cueing, consistent with proposals that face-selective regions may send gaze signals to parts of the dorsal and ventral frontoparietal attention networks. Finally, although the default-mode network is thought to be involved in social cognition, this role does not extend to gaze orienting as these regions were more deactivated following gaze cues and showed less functional connectivity with face-selective regions during gaze cues.

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Onofrj, M., J. P. Taylor, D. Monaco, R. Franciotti, F. Anzellotti, L. Bonanni, V. Onofrj et A. Thomas. « Visual Hallucinations in PD and Lewy Body Dementias : Old and New Hypotheses ». Behavioural Neurology 27, n^o 4 (2013) : 479–93. http://dx.doi.org/10.1155/2013/703924.

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Visual Hallucinations (VH) are a common non-motor symptom of Parkinson’s Disease (PD) and the Lewy body dementias (LBD) of Parkinson's disease with dementia (PDD) and Dementia with Lewy Bodies (DLB). The origin of VH in PD and LBD is debated: earlier studies considered a number of different possible mechanisms underlying VH including visual disorders, Rapid Eye Movement (REM) Sleep Intrusions, dysfunctions of top down or bottom up visual pathways, and neurotransmitter imbalance.More recently newer hypotheses introduce, among the possible mechanisms of VH, the role of attention networks (ventral and dorsal) and of the Default Mode Network (DMN) a network that is inhibited during attentional tasks and becomes active during rest and self referential imagery.Persistent DMN activity during active tasks with dysfunctional imbalance of dorsal and ventral attentional networks represents a new hypothesis on the mechanism of VH.We review the different methods used to classify VH and discuss reports supporting or challenging the different hypothetical mechanisms of VH.

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Bernard, Florian, Jean‐Michel Lemee, Edouard Mazerand, Louis‐Marie Leiber, Philippe Menei et Aram Ter Minassian. « The ventral attention network : the mirror of the language network in the right brain hemisphere ». Journal of Anatomy 237, n^o 4 (24 juin 2020) : 632–42. http://dx.doi.org/10.1111/joa.13223.

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Devaney, Kathryn, Emily Levin, Maya Rosen, Samantha Michalka et David Somers. « fMRI-based Functional Localization of the Ventral Attention Network in Individual Subjects ». Journal of Vision 15, n^o 12 (1 septembre 2015) : 435. http://dx.doi.org/10.1167/15.12.435.

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Palanca, Ben Julian A., Anish Mitra, Linda Larson-Prior, Abraham Z. Snyder, Michael S. Avidan et Marcus E. Raichle. « Resting-state Functional Magnetic Resonance Imaging Correlates of Sevoflurane-induced Unconsciousness ». Anesthesiology 123, n^o 2 (1 août 2015) : 346–56. http://dx.doi.org/10.1097/aln.0000000000000731.

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Abstract Background: Blood oxygen level–dependent (BOLD) functional magnetic resonance imaging (fMRI) has been used to study the effects of anesthetic agents on correlated intrinsic neural activity. Previous studies have focused primarily on intravenous agents. The authors studied the effects of sevoflurane, an inhaled anesthetic. Methods: Resting-state BOLD fMRI was acquired from 10 subjects before sedation and from 9 subjects rendered unresponsive by 1.2% sevoflurane. The fMRI data were analyzed taking particular care to minimize the impact of artifact generated by head motion. Results: BOLD correlations were specifically weaker within the default mode network and ventral attention network during sevoflurane-induced unconsciousness, especially between anterior and posterior midline regions. Reduced functional connectivity between these same networks and the thalamus was also spatially localized to the midline frontal regions. The amplitude of BOLD signal fluctuations was substantially reduced across all brain regions. The importance of censoring epochs contaminated by head motion was demonstrated by comparative analyses. Conclusions: Sevoflurane-induced unconsciousness is associated with both globally reduced BOLD signal amplitudes and selectively reduced functional connectivity within cortical networks associated with consciousness (default mode network) and orienting to salient external stimuli (ventral attention network). Scrupulous attention to minimizing the impact of head motion artifact is critical in fMRI studies using anesthetic agents.

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Lin, Haixi, Qingxia Lin, Hailong Li, Meihao Wang, Hong Chen, Yan Liang, Xuan Bu et al. « Functional Connectivity of Attention-Related Networks in Drug-Naïve Children With ADHD ». Journal of Attention Disorders 25, n^o 3 (27 septembre 2018) : 377–88. http://dx.doi.org/10.1177/1087054718802017.

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Objective: This study aimed to explore alterations of seed-based functional connectivity (FC) in dorsal attention network (DAN), ventral attention network (VAN), and default mode network (DMN) in ADHD children. Method: A voxel-based comparison of FC maps between 46 drug-naïve children with ADHD and 31 healthy controls (HCs) and correlation analysis between connectivity features and behavior were performed. Results: Compared with the HCs, children with ADHD were characterized by hyperconnectivity between DAN and regions of DMN and by hyperconnectivity between DMN and a set of regions involved in somatosensory, visual, and auditory cortices. No significant group different FC was found between VAN and the whole brain. Higher FC between DMN and somatosensory, visual, and auditory cortex was associated with better performance in attention and executive function. Conclusion: The dysregulation of networks in children with ADHD not only involves the DAN and DMN but also the somatosensory, motor, visual, and auditory networks.

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Corbetta, Maurizio, et Gordon L. Shulman. « Human cortical mechanisms of visual attention during orienting and search ». Philosophical Transactions of the Royal Society of London. Series B : Biological Sciences 353, n^o 1373 (29 août 1998) : 1353–62. http://dx.doi.org/10.1098/rstb.1998.0289.

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Functional anatomical studies indicate that a set of neural signals in parietal and frontal cortex mediates the covert allocation of attention to visual locations across a wide variety of visual tasks. This fronto–parietal network includes areas, such as the frontal eye field and supplementary eye field. This anatomical overlap suggests that shifts of attention to visual locations or objects recruit areas involved in oculomotor programming and execution. Finally, the fronto–parietal network may be the source of spatial attentional modulations in the ventral visual system during object recognition or discrimination.

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Marshall, Olga, Sanjeev Chawla, Hanzhang Lu, Louise Pape et Yulin Ge. « Cerebral blood flow modulation insufficiency in brain networks in multiple sclerosis : A hypercapnia MRI study ». Journal of Cerebral Blood Flow & ; Metabolism 36, n^o 12 (20 juillet 2016) : 2087–95. http://dx.doi.org/10.1177/0271678x16654922.

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Cerebrovascular reactivity measures vascular regulation of cerebral blood flow and is responsible for maintaining healthy neurovascular coupling. Multiple sclerosis exhibits progressive neurodegeneration and global cerebrovascular reactivity deficits. This study investigates varied degrees of cerebrovascular reactivity impairment in different brain networks, which may be an underlying cause for functional changes in the brain, affecting long-distance projection integrity and cognitive function; 28 multiple sclerosis and 28 control subjects underwent pseudocontinuous arterial spin labeling perfusion MRI to measure cerebral blood flow under normocapnia (room air) and hypercapnia (5% carbon dioxide gas mixture) breathing. Cerebrovascular reactivity, measured as normocapnic to hypercapnic cerebral blood flow percent increase normalized by end-tidal carbon dioxide change, was determined from seven functional networks (default mode, frontoparietal, somatomotor, visual, limbic, dorsal, and ventral attention networks). Group analysis showed significantly decreased cerebrovascular reactivity in patients compared to controls within the default mode, frontoparietal, somatomotor, and ventral attention networks after multiple comparison correction. Regression analysis showed a significant correlation of cerebrovascular reactivity with lesion load in the default mode and ventral attention networks and with gray matter atrophy in the default mode network. Functional networks in multiple sclerosis patients exhibit varied amounts of cerebrovascular reactivity deficits. Such blood flow regulation abnormalities may contribute to functional communication disruption in multiple sclerosis.

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Sylvester, Chad, Michael Perino, Daniel Pine, Steve Petersen, Deanna Barch et Joan Luby. « The Ventral Attention Network as a Novel Treatment Target for Pediatric Anxiety Disorders ». Biological Psychiatry 87, n^o 9 (mai 2020) : S64. http://dx.doi.org/10.1016/j.biopsych.2020.02.186.

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Briggs, Robert G., Andrew K. Conner, Cordell M. Baker, Joshua D. Burks, Chad A. Glenn, Goksel Sali, James D. Battiste, Daniel L. O’Donoghue et Michael E. Sughrue. « A Connectomic Atlas of the Human Cerebrum—Chapter 18 : The Connectional Anatomy of Human Brain Networks ». Operative Neurosurgery 15, suppl_1 (27 septembre 2018) : S470—S480. http://dx.doi.org/10.1093/ons/opy272.

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ABSTRACT BACKGROUND It is widely understood that cortical functions are mediated by complex, interdependent brain networks. These networks have been identified and studied using novel technologies such as functional magnetic resonance imaging under both resting-state and task-based conditions. However, no one has attempted to describe these networks in terms of their cortical parcellations. OBJECTIVE To describe our approach to network modeling and discuss its significance for the future of neuronavigation in brain surgery using the cortical parcellation scheme detailed within this supplement. METHODS Using network models previously elucidated by our group using coordinate-based meta-analytic techniques, we show the anatomic position and underlying white matter tracts of the cortical regions comprising 8 functional networks of the human cerebrum. These network models are displayed using Synaptive's clinically available BrightMatter tractography software (Synaptive Medical, Toronto, Canada). RESULTS The relevant cortical parcellations of 8 different cerebral networks have been identified. The fiber tracts between these regions were used to construct anatomically precise models of the networks. Models are described for the dorsal attention, ventral attention, semantic, auditory, supplementary motor, ventral premotor, default mode, and salience networks. CONCLUSION Our goal is to move towards more precise, anatomically specific models of brain networks that can be constructed for individual patients and utilized in navigational platforms during brain surgery. We believe network modeling and future advances in navigation technology can provide a foundation for improving neurosurgical outcomes by allowing us to preserve complex brain networks.

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Luo, Xiaoliang, Brett D. Roads et Bradley C. Love. « The Costs and Benefits of Goal-Directed Attention in Deep Convolutional Neural Networks ». Computational Brain & ; Behavior 4, n^o 2 (12 février 2021) : 213–30. http://dx.doi.org/10.1007/s42113-021-00098-y.

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AbstractPeople deploy top-down, goal-directed attention to accomplish tasks, such as finding lost keys. By tuning the visual system to relevant information sources, object recognition can become more efficient (a benefit) and more biased toward the target (a potential cost). Motivated by selective attention in categorisation models, we developed a goal-directed attention mechanism that can process naturalistic (photographic) stimuli. Our attention mechanism can be incorporated into any existing deep convolutional neural networks (DCNNs). The processing stages in DCNNs have been related to ventral visual stream. In that light, our attentional mechanism incorporates top-down influences from prefrontal cortex (PFC) to support goal-directed behaviour. Akin to how attention weights in categorisation models warp representational spaces, we introduce a layer of attention weights to the mid-level of a DCNN that amplify or attenuate activity to further a goal. We evaluated the attentional mechanism using photographic stimuli, varying the attentional target. We found that increasing goal-directed attention has benefits (increasing hit rates) and costs (increasing false alarm rates). At a moderate level, attention improves sensitivity (i.e. increases $d^{\prime }$ d ′ ) at only a moderate increase in bias for tasks involving standard images, blended images and natural adversarial images chosen to fool DCNNs. These results suggest that goal-directed attention can reconfigure general-purpose DCNNs to better suit the current task goal, much like PFC modulates activity along the ventral stream. In addition to being more parsimonious and brain consistent, the mid-level attention approach performed better than a standard machine learning approach for transfer learning, namely retraining the final network layer to accommodate the new task.

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Webb, Taylor W., Kajsa M. Igelström, Aaron Schurger et Michael S. A. Graziano. « Cortical networks involved in visual awareness independent of visual attention ». Proceedings of the National Academy of Sciences 113, n^o 48 (14 novembre 2016) : 13923–28. http://dx.doi.org/10.1073/pnas.1611505113.

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It is now well established that visual attention, as measured with standard spatial attention tasks, and visual awareness, as measured by report, can be dissociated. It is possible to attend to a stimulus with no reported awareness of the stimulus. We used a behavioral paradigm in which people were aware of a stimulus in one condition and unaware of it in another condition, but the stimulus drew a similar amount of spatial attention in both conditions. The paradigm allowed us to test for brain regions active in association with awareness independent of level of attention. Participants performed the task in an MRI scanner. We looked for brain regions that were more active in the aware than the unaware trials. The largest cluster of activity was obtained in the temporoparietal junction (TPJ) bilaterally. Local independent component analysis (ICA) revealed that this activity contained three distinct, but overlapping, components: a bilateral, anterior component; a left dorsal component; and a right dorsal component. These components had brain-wide functional connectivity that partially overlapped the ventral attention network and the frontoparietal control network. In contrast, no significant activity in association with awareness was found in the banks of the intraparietal sulcus, a region connected to the dorsal attention network and traditionally associated with attention control. These results show the importance of separating awareness and attention when testing for cortical substrates. They are also consistent with a recent proposal that awareness is associated with ventral attention areas, especially in the TPJ.

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Patel, Gaurav H., Danica Yang, Emery C. Jamerson, Lawrence H. Snyder, Maurizio Corbetta et Vincent P. Ferrera. « Functional evolution of new and expanded attention networks in humans ». Proceedings of the National Academy of Sciences 112, n^o 30 (13 juillet 2015) : 9454–59. http://dx.doi.org/10.1073/pnas.1420395112.

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Macaques are often used as a model system for invasive investigations of the neural substrates of cognition. However, 25 million years of evolution separate humans and macaques from their last common ancestor, and this has likely substantially impacted the function of the cortical networks underlying cognitive processes, such as attention. We examined the homology of frontoparietal networks underlying attention by comparing functional MRI data from macaques and humans performing the same visual search task. Although there are broad similarities, we found fundamental differences between the species. First, humans have more dorsal attention network areas than macaques, indicating that in the course of evolution the human attention system has expanded compared with macaques. Second, potentially homologous areas in the dorsal attention network have markedly different biases toward representing the contralateral hemifield, indicating that the underlying neural architecture of these areas may differ in the most basic of properties, such as receptive field distribution. Third, despite clear evidence of the temporoparietal junction node of the ventral attention network in humans as elicited by this visual search task, we did not find functional evidence of a temporoparietal junction in macaques. None of these differences were the result of differences in training, experimental power, or anatomical variability between the two species. The results of this study indicate that macaque data should be applied to human models of cognition cautiously, and demonstrate how evolution may shape cortical networks.

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Yu, Chen-Ping, Huidong Liu, Dimitrios Samaras et Gregory J. Zelinsky. « Modelling attention control using a convolutional neural network designed after the ventral visual pathway ». Visual Cognition 27, n^o 5-8 (5 septembre 2019) : 416–34. http://dx.doi.org/10.1080/13506285.2019.1661927.

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Ahrens, Merle-Marie, Domenica Veniero, Inga Marie Freund, Monika Harvey et Gregor Thut. « Both dorsal and ventral attention network nodes are implicated in exogenously driven visuospatial anticipation ». Cortex 117 (août 2019) : 168–81. http://dx.doi.org/10.1016/j.cortex.2019.02.031.

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Wang, Chunli, Huanhuan Cai, Xuetian Sun, Li Si, Min Zhang, Yuanhong Xu, Yinfeng Qian et Jiajia Zhu. « Large-Scale Internetwork Functional Connectivity Mediates the Relationship between Serum Triglyceride and Working Memory in Young Adulthood ». Neural Plasticity 2020 (1 novembre 2020) : 1–8. http://dx.doi.org/10.1155/2020/8894868.

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Previous research has demonstrated that serum lipid profile is associated with cognitive function as well as brain structure and function in middle-aged, elderly, and clinical populations. However, the nature and extent of lipids-brain-cognition relationships in young adulthood are largely unknown. In this study, 157 healthy young adults underwent resting-state functional MRI scans. Functional connectivity between and within 14 functional networks were calculated using independent component analysis. Peripheral venous blood samples were collected to measure serum lipids. Working memory was assessed using a 3-back task. Linear regression, correlation, and mediation analyses were conducted to test for potential associations between serum lipids, inter- and intranetwork functional connectivity, and working memory performance. We found that higher serum triglyceride (TG) level was correlated with stronger connectivity between left frontoparietal and ventral attention networks, between right frontoparietal and dorsal attention networks, between right frontoparietal and dorsal sensorimotor networks, between right frontoparietal and lateral visual networks, and between salience (SN) and ventral sensorimotor (vSMN) networks, as well as lower connectivity between posterior default mode and left frontoparietal networks, between left frontoparietal and medial visual networks, and between ventral attention and dorsal sensorimotor networks. In addition, higher SN-vSMN connectivity was related to lower 3-back accuracy. More importantly, the relationship between serum TG and 3-back accuracy was mediated by SN-vSMN connectivity. Our findings not only may expand existing knowledge regarding serum lipids-brain-cognition relations from the perspective of large-scale functional network organization but also may inform a translational conceptualization of how to improve cognitive function through regulating serum lipids.

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McMains, S., et S. Kastner. « Do spatial attention and long-term memory systems overlap ? Dorsal and ventral attention network engagement during memory retrieval processes ». Journal of Vision 11, n^o 11 (23 septembre 2011) : 180. http://dx.doi.org/10.1167/11.11.180.

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Van Calster, Laurens, Arnaud D'Argembeau, Eric Salmon, Frédéric Peters et Steve Majerus. « Fluctuations of Attentional Networks and Default Mode Network during the Resting State Reflect Variations in Cognitive States : Evidence from a Novel Resting-state Experience Sampling Method ». Journal of Cognitive Neuroscience 29, n^o 1 (janvier 2017) : 95–113. http://dx.doi.org/10.1162/jocn_a_01025.

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Neuroimaging studies have revealed the recruitment of a range of neural networks during the resting state, which might reflect a variety of cognitive experiences and processes occurring in an individual's mind. In this study, we focused on the default mode network (DMN) and attentional networks and investigated their association with distinct mental states when participants are not performing an explicit task. To investigate the range of possible cognitive experiences more directly, this study proposes a novel method of resting-state fMRI experience sampling, informed by a phenomenological investigation of the fluctuation of mental states during the resting state. We hypothesized that DMN activity would increase as a function of internal mentation and that the activity of dorsal and ventral networks would indicate states of top–down versus bottom–up attention at rest. Results showed that dorsal attention network activity fluctuated as a function of subjective reports of attentional control, providing evidence that activity of this network reflects the perceived recruitment of controlled attentional processes during spontaneous cognition. Activity of the DMN increased when participants reported to be in a subjective state of internal mentation, but not when they reported to be in a state of perception. This study provides direct evidence for a link between fluctuations of resting-state neural activity and fluctuations in specific cognitive processes.

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Carballedo, A., M. Doyle, G. Lavelle, J. Gormley, V. O'Keane et T. Frodl. « Affective Network Hyperconnectivity and Hypoconnectivity of Cognitive Control and Ventral Attention Networks in Adults with High Neuroticism Scores ». European Psychiatry 30 (mars 2015) : 252. http://dx.doi.org/10.1016/s0924-9338(15)30207-8.

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Gao, Yingxue, Dandan Shuai, Xuan Bu, Xinyu Hu, Shi Tang, Lianqing Zhang, Hailong Li et al. « Impairments of large-scale functional networks in attention-deficit/hyperactivity disorder : a meta-analysis of resting-state functional connectivity ». Psychological Medicine 49, n^o 15 (10 septembre 2019) : 2475–85. http://dx.doi.org/10.1017/s003329171900237x.

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AbstractAltered resting-state functional connectivity (rsFC) has been noted in large-scale functional networks in attention-deficit/hyperactivity disorder (ADHD). However, identifying consistent abnormalities of functional networks is difficult due to varied methods and results across studies. To integrate rsFC alterations and search for coherent patterns of intrinsic functional network impairments in ADHD, this research conducts a coordinate-based meta-analysis of voxel-wise seed-based rsFC studies comparing rsFC between ADHD patients and healthy controls. A total of 25 datasets from 21 studies including 700 ADHD patients and 580 controls were analyzed. We extracted the coordinates of seeds and between-group effects. Each seed was then categorized into a seed-network by its location within priori 7-network parcellations. Then, pooled meta-analyses were conducted for the default mode network (DMN), frontoparietal network (FPN) and affective network (AN) separately, but not for the ventral attention network (VAN), dorsal attention network (DAN), somatosensory network (SSN) and visual network due to a lack of primary studies. The results showed that ADHD was characterized by hyperconnectivity between the FPN and regions of the DMN and AN as well as hypoconnectivity between the FPN and regions of the VAN and SSN. These findings not only support the triple-network model of pathophysiology associated with ADHD but also extend this model by highlighting the involvement of the SSN and AN in the mechanisms of network interactions that may account for motor hyperactivity and impulsive symptoms.

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Chumin, Evgeny J., Shannon L. Risacher, John D. West, Liana G. Apostolova, Martin R. Farlow, Brenna C. McDonald, Yu-Chien Wu, Andrew J. Saykin et Olaf Sporns. « Temporal stability of the ventral attention network and general cognition along the Alzheimer’s disease spectrum ». NeuroImage : Clinical 31 (2021) : 102726. http://dx.doi.org/10.1016/j.nicl.2021.102726.

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Yang, Wenjing, Kaixiang Zhuang, Peiduo Liu, Yuhua Guo, Qunlin Chen, Dongtao Wei et Jiang Qiu. « Memory Suppression Ability can be Robustly Predicted by the Internetwork Communication of Frontoparietal Control Network ». Cerebral Cortex 31, n^o 7 (1 mars 2021) : 3451–61. http://dx.doi.org/10.1093/cercor/bhab024.

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Abstract Memory suppression (MS) is essential for mental well-being. However, no studies have explored how intrinsic resting-state functional connectivity (rs-FC) predicts this ability. Here, we adopted the connectome-based predictive modeling (CPM) based on the resting-state fMRI data to investigate whether and how rs-FC profiles in predefined brain networks (the frontoparietal control networks or FPCN) can predict MS in healthy individuals with 497 participants. The MS ability was assessed by MS-induced forgetting during the think/no-think paradigm. The results showed that FPCN network was especially informative for generating the prediction model for MS. Some regions of FPCN, such as middle frontal gyrus, superior frontal gyrus and inferior parietal lobe were critical in predicting MS. Moreover, functional interplay between FPCN and multiple networks, such as dorsal attention network (DAN), ventral attention network (VAN), default mode network (DMN), the limbic system and subcortical regions, enabled prediction of MS. Crucially, the predictive FPCN networks were stable and specific to MS. These results indicated that FPCN flexibility interacts with other networks to underpin the ability of MS. These would also be beneficial for understanding how compromises in these functional networks may have led to the intrusive thoughts and memories characterized in some mental disorders.

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Yu, Meichen, Kristin A. Linn, Russell T. Shinohara, Desmond J. Oathes, Philip A. Cook, Romain Duprat, Tyler M. Moore et al. « Childhood trauma history is linked to abnormal brain connectivity in major depression ». Proceedings of the National Academy of Sciences 116, n^o 17 (8 avril 2019) : 8582–90. http://dx.doi.org/10.1073/pnas.1900801116.

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Patients with major depressive disorder (MDD) present with heterogeneous symptom profiles, while neurobiological mechanisms are still largely unknown. Brain network studies consistently report disruptions of resting-state networks (RSNs) in patients with MDD, including hypoconnectivity in the frontoparietal network (FPN), hyperconnectivity in the default mode network (DMN), and increased connection between the DMN and FPN. Using a large, multisite fMRI dataset (n= 189 patients with MDD,n= 39 controls), we investigated network connectivity differences within and between RSNs in patients with MDD and healthy controls. We found that MDD could be characterized by a network model with the following abnormalities relative to controls: (i) lower within-network connectivity in three task-positive RSNs [FPN, dorsal attention network (DAN), and cingulo-opercular network (CON)], (ii) higher within-network connectivity in two intrinsic networks [DMN and salience network (SAN)], and (iii) higher within-network connectivity in two sensory networks [sensorimotor network (SMN) and visual network (VIS)]. Furthermore, we found significant alterations in connectivity between a number of these networks. Among patients with MDD, a history of childhood trauma and current symptoms quantified by clinical assessments were associated with a multivariate pattern of seven different within- and between-network connectivities involving the DAN, FPN, CON, subcortical regions, ventral attention network (VAN), auditory network (AUD), VIS, and SMN. Overall, our study showed that traumatic childhood experiences and dimensional symptoms are linked to abnormal network architecture in MDD. Our results suggest that RSN connectivity may explain underlying neurobiological mechanisms of MDD symptoms and has the potential to serve as an effective diagnostic biomarker.

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Veldsman, Michele, Leonid Churilov, Emilio Werden, Qi Li, Toby Cumming et Amy Brodtmann. « Physical Activity After Stroke Is Associated With Increased Interhemispheric Connectivity of the Dorsal Attention Network ». Neurorehabilitation and Neural Repair 31, n^o 2 (24 septembre 2016) : 157–67. http://dx.doi.org/10.1177/1545968316666958.

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Background. Attention is frequently impaired after stroke, and its impairment is associated with poor quality of life. Physical activity benefits attention in healthy populations and has also been associated with recovery after brain injury. Objective. We investigated the relationship between objectively measured daily physical activity, attention network connectivity, and attention task performance after stroke. We hypothesized that increased daily physical activity would be associated with improved attention network function. Methods. Stroke patients (n = 62; mean age = 67 years, SD = 12.6 years) and healthy controls (n = 27; mean age = 68 years, SD = 6 years) underwent cognitive testing and 7 minutes of functional magnetic resonance imaging in the resting-state. Patients were tested 3 months after ischemic stroke. Physical activity was monitored with an electronic armband worn for 7 days. Dorsal and ventral attention network function was examined using seed-based connectivity analyses. Results. Greater daily physical activity was associated with increased interhemispheric connectivity of the superior parietal lobule in the dorsal attention network (DAN; P < .05, false discovery rate corrected). This relationship was not explained by stroke lesion volume. Importantly, stronger connectivity in this region was related to faster reaction time in 3 attention tasks, as revealed by robust linear regression. The relationship remained after adjusting for age, gray matter volume, and white matter hyperintensity load. Conclusions. Daily physical activity was associated with increased resting interhemispheric connectivity of the DAN. Increased connectivity was associated with faster attention performance, suggesting a cognitive correlate to increased network connectivity. Attentional modulation by physical activity represents a key focus for intervention studies.

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Beume, Lena-Alexandra, Christoph P. Kaller, Markus Hoeren, Stefan Klöppel, Dorothee Kuemmerer, Volkmar Glauche, Lena Köstering et al. « Processing of bilateral versus unilateral conditions : Evidence for the functional contribution of the ventral attention network ». Cortex 66 (mai 2015) : 91–102. http://dx.doi.org/10.1016/j.cortex.2015.02.018.

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Alavash, Mohsen, Sarah Tune et Jonas Obleser. « Modular reconfiguration of an auditory control brain network supports adaptive listening behavior ». Proceedings of the National Academy of Sciences 116, n^o 2 (26 décembre 2018) : 660–69. http://dx.doi.org/10.1073/pnas.1815321116.

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Speech comprehension in noisy, multitalker situations poses a challenge. Successful behavioral adaptation to a listening challenge often requires stronger engagement of auditory spatial attention and context-dependent semantic predictions. Human listeners differ substantially in the degree to which they adapt behaviorally and can listen successfully under such circumstances. How cortical networks embody this adaptation, particularly at the individual level, is currently unknown. We here explain this adaptation from reconfiguration of brain networks for a challenging listening task (i.e., a linguistic variant of the Posner paradigm with concurrent speech) in an age-varying sample of n = 49 healthy adults undergoing resting-state and task fMRI. We here provide evidence for the hypothesis that more successful listeners exhibit stronger task-specific reconfiguration (hence, better adaptation) of brain networks. From rest to task, brain networks become reconfigured toward more localized cortical processing characterized by higher topological segregation. This reconfiguration is dominated by the functional division of an auditory and a cingulo-opercular module and the emergence of a conjoined auditory and ventral attention module along bilateral middle and posterior temporal cortices. Supporting our hypothesis, the degree to which modularity of this frontotemporal auditory control network is increased relative to resting state predicts individuals’ listening success in states of divided and selective attention. Our findings elucidate how fine-tuned cortical communication dynamics shape selection and comprehension of speech. Our results highlight modularity of the auditory control network as a key organizational principle in cortical implementation of auditory spatial attention in challenging listening situations.

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Tipper, Christine M., Todd C. Handy, Barry Giesbrecht et Alan Kingstone. « Brain Responses to Biological Relevance ». Journal of Cognitive Neuroscience 20, n^o 5 (mai 2008) : 879–91. http://dx.doi.org/10.1162/jocn.2008.20510.

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This study examines whether orienting attention to biologically based social cues engages neural mechanisms distinct from those engaged by orienting to nonbiologically based nonsocial cues. Participants viewed a perceptually ambiguous stimulus presented centrally while performing a target detection task. By having participants alternate between viewing this stimulus as an eye in profile or an arrowhead, we were able to directly compare the neural mechanisms of attentional orienting to social and nonsocial cues while holding the physical stimulus constant. The functional magnetic resonance imaging results indicated that attentional orienting to both eye gaze and arrow cues engaged extensive dorsal and ventral fronto-parietal networks. Eye gaze cues, however, more vigorously engaged two regions in the ventral frontal cortex associated with attentional reorienting to salient or meaningful stimuli, as well as lateral occipital regions. An event-related potential study demonstrated that this enhanced occipital response was attributable to a higher-amplitude sensory gain effect for targets appearing at locations cued by eye gaze than for those cued by an arrowhead. These results endorse the hypothesis that differences in attention to social and nonsocial cues are quantitative rather than qualitative, running counter to current models that assume enhanced processing for social stimuli reflects the involvement of a unique network of brain regions. An intriguing implication of the present study is the possibility that our ability to orient volitionally and reflexively to socially irrelevant stimuli, including arrowheads, may have arisen as a useful by-product of a system that developed first, and foremost, to promote social orienting to stimuli that are biologically relevant.

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Sawczak, Caspian M., Alexander J. Barnett et Melanie Cohn. « Increased Cortical Thickness in Attentional Networks in Parkinson’s Disease with Minor Hallucinations ». Parkinson's Disease 2019 (2 mai 2019) : 1–6. http://dx.doi.org/10.1155/2019/5351749.

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Hallucinations are common in Parkinson’s disease (PD). Based on functional brain MRI data, hallucinations are proposed to result from alterations in the dorsal attention network (DAN), ventral attention network (VAN), and default mode network. Using structural MRI data from Parkinson’s Progression Markers Initiative (PPMI), we examined cortical thickness in these networks in PD patients with (n=30) and without (n=30) minor hallucinations who were matched on multiple clinical characteristics (e.g., age, sex, education, cognitive diagnosis, MoCA score, medication, disease duration, and severity) as well as healthy controls (n=30) matched on demographic variables. Multivariate analyses revealed mild hallucinations to be associated with thicker cortex in the DAN and VAN, and these effects were driven by the left superior precentral sulcus and postcentral sulcus for the DAN and by the right insular gyrus for the VAN. While these findings may seem at odds with prior work showing grey matter reductions, our patients are in earlier stages of the disease than those in other studies. This is consistent with an inverted U-shape pattern of cortical thickness alterations in other neurodegenerative diseases and warrants further investigations in longitudinal studies tracking brain correlates of PD psychosis progression.

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Chomiak, T., S. Peters et B. Hu. « Functional Architecture and Spike Timing Properties of Corticofugal Projections From Rat Ventral Temporal Cortex ». Journal of Neurophysiology 100, n^o 1 (juillet 2008) : 327–35. http://dx.doi.org/10.1152/jn.90392.2008.

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Sensory association and parahippocampal cortex in the ventral temporal lobe plays an important role in sensory object recognition and control of top-down attention. Although layer V neurons located in high-order cortical structures project to multiple cortical and subcortical regions, the architecture and functional organization of this large axonal network are poorly understood. Using a large in vitro slice preparation, we examined the functional organization and spike timing properties of the descending layer V axonal network. We found that most, if not all, layer V neurons in this region can form multiple axonal pathways that project to many brain structures, both proximal and remote. The conduction velocities of different axonal pathways are highly diverse and can vary up to more than threefold. Nevertheless for those axonal projections on the ipsilateral side, the speeds of axonal conduction appear to be tuned to their length. As such, spike delivery becomes nearly isochronic along these pathways regardless of projection distance. In contrast, axons projecting to the contralateral hemisphere are significantly slower and do not participate in this lateralized isochronicity. These structural and functional features of layer V network from the ventral temporal lobe may play an important role in top-down control of sensory cue processing and attention.

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Zheng, Weihao, Choong-Wan Woo, Zhijun Yao, Pavel Goldstein, Lauren Y. Atlas, Mathieu Roy, Liane Schmidt et al. « Pain-Evoked Reorganization in Functional Brain Networks ». Cerebral Cortex 30, n^o 5 (9 décembre 2019) : 2804–22. http://dx.doi.org/10.1093/cercor/bhz276.

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Abstract Recent studies indicate that a significant reorganization of cerebral networks may occur in patients with chronic pain, but how immediate pain experience influences the organization of large-scale functional networks is not yet well characterized. To investigate this question, we used functional magnetic resonance imaging in 106 participants experiencing both noxious and innocuous heat. Painful stimulation caused network-level reorganization of cerebral connectivity that differed substantially from organization during innocuous stimulation and standard resting-state networks. Noxious stimuli increased somatosensory network connectivity with (a) frontoparietal networks involved in context representation, (b) “ventral attention network” regions involved in motivated action selection, and (c) basal ganglia and brainstem regions. This resulted in reduced “small-worldness,” modularity (fewer networks), and global network efficiency and in the emergence of an integrated “pain supersystem” (PS) whose activity predicted individual differences in pain sensitivity across 5 participant cohorts. Network hubs were reorganized (“hub disruption”) so that more hubs were localized in PS, and there was a shift from “connector” hubs linking disparate networks to “provincial” hubs connecting regions within PS. Our findings suggest that pain reorganizes the network structure of large-scale brain systems. These changes may prioritize responses to painful events and provide nociceptive systems privileged access to central control of cognition and action during pain.

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Corbetta, Maurizio, J. Michelle Kincade et Gordon L. Shulman. « Neural Systems for Visual Orienting and Their Relationships to Spatial Working Memory ». Journal of Cognitive Neuroscience 14, n^o 3 (1 avril 2002) : 508–23. http://dx.doi.org/10.1162/089892902317362029.

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We investigated neural correlates of human visual orienting using event-related functional magnetic resonance imaging (fMRI). When subjects voluntarily directed attention to a peripheral location, we recorded robust and sustained signals uniquely from the intraparietal sulcus (IPs) and superior frontal cortex (near the frontal eye field, FEF). In the ventral IPs and FEF only, the blood oxygen level dependent signal was modulated by the direction of attention. The IPs and FEF also maintained the most sustained level of activation during a 7-sec delay, when subjects maintained attention at the peripheral cued location (working memory). Therefore, the IPs and FEF form a dorsal network that controls the endogenous allocation and maintenance of visuospatial attention. A separate right hemisphere network was activated by the detection of targets at unattended locations. Activation was largely independent of the target's location (visual field). This network included among other regions the right temporo-parietal junction and the inferior frontal gyrus. We propose that this cortical network is important for reorienting to sensory events.

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Kwok, Sze Chai, Tim Shallice et Emiliano Macaluso. « Set-relevance Determines the Impact of Distractors on Episodic Memory Retrieval ». Journal of Cognitive Neuroscience 26, n^o 9 (septembre 2014) : 2070–86. http://dx.doi.org/10.1162/jocn_a_00601.

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We investigated the interplay between stimulus-driven attention and memory retrieval with a novel interference paradigm that engaged both systems concurrently on each trial. Participants encoded a 45-min movie on Day 1 and, on Day 2, performed a temporal order judgment task during fMRI. Each retrieval trial comprised three images presented sequentially, and the task required participants to judge the temporal order of the first and the last images (“memory probes”) while ignoring the second image, which was task irrelevant (“attention distractor”). We manipulated the content relatedness and the temporal proximity between the distractor and the memory probes, as well as the temporal distance between two probes. Behaviorally, short temporal distances between the probes led to reduced retrieval performance. Distractors that at encoding were temporally close to the first probe image reduced these costs, specifically when the distractor was content unrelated to the memory probes. The imaging results associated the distractor probe temporal proximity with activation of the right ventral attention network. By contrast, the precuneus was activated for high-content relatedness between distractors and probes and in trials including a short distance between the two memory probes. The engagement of the right ventral attention network by specific types of distractors suggests a link between stimulus-driven attention control and episodic memory retrieval, whereas the activation pattern of the precuneus implicates this region in memory search within knowledge/content-based hierarchies.

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Weissman, Daniel H., et Jérôme Prado. « Heightened activity in a key region of the ventral attention network is linked to reduced activity in a key region of the dorsal attention network during unexpected shifts of covert visual spatial attention ». NeuroImage 61, n^o 4 (juillet 2012) : 798–804. http://dx.doi.org/10.1016/j.neuroimage.2012.03.032.

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Afzali, Mohammad H., Alain Dagher, Hanie Edalati, Josiane Bourque, Sean Spinney, Rachel J. Sharkey et Patricia Conrod. « Adolescent Resting-State Brain Networks and Unique Variability of Conduct Problems Within the Externalizing Dimension ». Journal of Personality Disorders 34, n^o 5 (octobre 2020) : 609–27. http://dx.doi.org/10.1521/pedi.2020.34.5.609.

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The externalizing psychopathological dimension is associated with alterations in adolescents’ functional brain connectivity. The current study aims to identify the functional correlates of the unique variability in conduct problems within the context of the broad externalizing dimension. The broad externalizing dimension and unique variability in conduct problems were estimated using a bifactor model. Resting-state data were available for a sample of 125 adolescents. Based on multiresolution parcellation of functional brain networks atlas, major resting-state functional brain networks and the connectivity correlates of unique conduct problems and the broad externalizing dimension were established. The broad externalizing dimension was related to connectivity alterations in the ventral attention/salience network, while unique variability in conduct problems dimension was related to connectivity alterations in the cerebellum crusi as well as the mesolimbic network. The current study is a first step toward the identification of functional resting-state network correlates of broad and specific variability in the externalizing dimension.

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Taskov, Tihomir, et Juliana Dushanova. « Functional Connectivity in Developmental Dyslexia during Speed Discrimination ». Symmetry 13, n^o 5 (25 avril 2021) : 749. http://dx.doi.org/10.3390/sym13050749.

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A universal signature of developmental dyslexia is literacy acquisition impairments. Besides, dyslexia may be related to deficits in selective spatial attention, in the sensitivity to global visual motion, speed processing, oculomotor coordination, and integration of auditory and visual information. Whether motion-sensitive brain areas of children with dyslexia can recognize different speeds of expanded optic flow and segregate the slow-speed from high-speed contrast of motion was a main question of the study. A combined event-related EEG experiment with optic flow visual stimulation and functional frequency-based graph approach (small-world propensity ϕ) were applied to research the responsiveness of areas, which are sensitive to motion, and also distinguish slow/fast -motion conditions on three groups of children: controls, untrained (pre-D) and trained dyslexics (post-D) with visual intervention programs. Lower ϕ at θ, α, γ1-frequencies (low-speed contrast) for controls than other groups represent that the networks rewire, expressed at β frequencies (both speed contrasts) in the post-D, whose network was most segregated. Functional connectivity nodes have not existed in pre-D at dorsal medial temporal area MT+/V5 (middle, superior temporal gyri), left-hemispheric middle occipital gyrus/visual V2, ventral occipitotemporal (fusiform gyrus/visual V4), ventral intraparietal (supramarginal, angular gyri), derived from θ-frequency network for both conditions. After visual training, compensatory mechanisms appeared to implicate/regain these brain areas in the left hemisphere through plasticity across extended brain networks. Specifically, for high-speed contrast, the nodes were observed in pre-D (θ-frequency) and post-D (β2-frequency) relative to controls in hyperactivity of the right dorsolateral prefrontal cortex, which might account for the attentional network and oculomotor control impairments in developmental dyslexia.

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Liu, Careesa C., Sujoy Ghosh Hajra, Xiaowei Song, Sam M. Doesburg, Teresa P. L. Cheung et Ryan C. N. D'Arcy. « Cognitive loading via mental arithmetic modulates effects of blink-related oscillations on precuneus and ventral attention network regions ». Human Brain Mapping 40, n^o 2 (21 septembre 2018) : 377–93. http://dx.doi.org/10.1002/hbm.24378.

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Barrett, A. M., Olga Boukrina et Soha Saleh. « Ventral attention and motor network connectivity is relevant to functional impairment in spatial neglect after right brain stroke ». Brain and Cognition 129 (février 2019) : 16–24. http://dx.doi.org/10.1016/j.bandc.2018.11.013.

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Sylvester, Chad M., Deanna M. Barch, Maurizio Corbetta, Jonathan D. Power, Bradley L. Schlaggar et Joan L. Luby. « Resting State Functional Connectivity of the Ventral Attention Network in Children With a History of Depression or Anxiety ». Journal of the American Academy of Child & ; Adolescent Psychiatry 52, n^o 12 (décembre 2013) : 1326–36. http://dx.doi.org/10.1016/j.jaac.2013.10.001.

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Pollmann, S., R. Weidner, H. J. Müller et D. Y. von Cramon. « A Fronto-Posterior Network Involved in Visual Dimension Changes ». Journal of Cognitive Neuroscience 12, n^o 3 (mai 2000) : 480–94. http://dx.doi.org/10.1162/089892900562156.

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Objects characterized by a unique visual feature may pop out of their environment. When participants have to search for such “odd-one-out” targets, detection is facilitated when targets are consistently defined within the same feature dimension (e.g., color) compared with when the target dimension is uncertain (e.g., color or motion). Further, with dimensional uncertainty, there is a cost when a given target is defined in a different dimension to the preceding target, relative to when the critical dimension remains the same. Behavioral evidence suggests that a target dimension change involves a shift of attention to the new dimension. The present fMRI study revealed increased activation in the left frontopolar cortex, as well as in posterior visual areas of the dorsal and ventral streams, specific to changes in the target dimension. In contrast, activation in the striate cortex was decreased. This pattern suggests control of cross-dimensional attention shifts by the frontopolar cortex, modulating visual cortical processing by increased activation in higher-tier visual areas and suppression of activation in lower-tier areas.

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Kim, Byung-Hoon, Hesun Erin Kim, Jung Suk Lee et Jae-Jin Kim. « Anhedonia Relates to the Altered Global and Local Grey Matter Network Properties in Schizophrenia ». Journal of Clinical Medicine 10, n^o 7 (31 mars 2021) : 1395. http://dx.doi.org/10.3390/jcm10071395.

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Anhedonia is one of the major negative symptoms in schizophrenia and defined as the loss of hedonic experience to various stimuli in real life. Although structural magnetic resonance imaging has provided a deeper understanding of anhedonia-related abnormalities in schizophrenia, network analysis of the grey matter focusing on this symptom is lacking. In this study, single-subject grey matter networks were constructed in 123 patients with schizophrenia and 160 healthy controls. The small-world property of the grey matter network and its correlations with the level of physical and social anhedonia were evaluated using graph theory analysis. In the global scale whole-brain analysis, the patients showed reduced small-world property of the grey matter network. The local-scale analysis further revealed reduced small-world property in the default mode network, salience/ventral attention network, and visual network. The regional-level analysis showed an altered relationship between the small-world properties and the social anhedonia scale scores in the cerebellar lobule in patients with schizophrenia. These results indicate that anhedonia in schizophrenia may be related to abnormalities in the grey matter network at both the global whole-brain scale and local–regional scale.

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