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Alais D, Coorey J, Blake R, Davidson MJ. A new 'CFS tracking' paradigm reveals uniform suppression depth regardless of target complexity or salience. eLife 2024; 12:RP91019. [PMID: 38682887 PMCID: PMC11057872 DOI: 10.7554/elife.91019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2024] Open
Abstract
When the eyes view separate and incompatible images, the brain suppresses one image and promotes the other into visual awareness. Periods of interocular suppression can be prolonged during continuous flash suppression (CFS) - when one eye views a static 'target' while the other views a complex dynamic stimulus. Measuring the time needed for a suppressed image to break CFS (bCFS) has been widely used to investigate unconscious processing, and the results have generated controversy regarding the scope of visual processing without awareness. Here, we address this controversy with a new 'CFS tracking' paradigm (tCFS) in which the suppressed monocular target steadily increases in contrast until breaking into awareness (as in bCFS) after which it decreases until it again disappears (reCFS), with this cycle continuing for many reversals. Unlike bCFS, tCFS provides a measure of suppression depth by quantifying the difference between breakthrough and suppression thresholds. tCFS confirms that (i) breakthrough thresholds indeed differ across target types (e.g. faces vs gratings, as bCFS has shown) - but (ii) suppression depth does not vary across target types. Once the breakthrough contrast is reached for a given stimulus, all stimuli require a strikingly uniform reduction in contrast to reach the corresponding suppression threshold. This uniform suppression depth points to a single mechanism of CFS suppression, one that likely occurs early in visual processing because suppression depth was not modulated by target salience or complexity. More fundamentally, it shows that variations in bCFS thresholds alone are insufficient for inferring whether the barrier to achieving awareness exerted by interocular suppression is weaker for some categories of visual stimuli compared to others.
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Affiliation(s)
- David Alais
- School of Psychology, The University of SydneySydneyAustralia
| | - Jacob Coorey
- School of Psychology, The University of SydneySydneyAustralia
| | - Randolph Blake
- Department of Psychology, Vanderbilt UniversityNashvilleUnited States
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2
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Einhäuser W, Neubert CR, Grimm S, Bendixen A. High visual salience of alert signals can lead to a counterintuitive increase of reaction times. Sci Rep 2024; 14:8858. [PMID: 38632303 PMCID: PMC11024089 DOI: 10.1038/s41598-024-58953-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 03/26/2024] [Indexed: 04/19/2024] Open
Abstract
It is often assumed that rendering an alert signal more salient yields faster responses to this alert. Yet, there might be a trade-off between attracting attention and distracting from task execution. Here we tested this in four behavioral experiments with eye-tracking using an abstract alert-signal paradigm. Participants performed a visual discrimination task (primary task) while occasional alert signals occurred in the visual periphery accompanied by a congruently lateralized tone. Participants had to respond to the alert before proceeding with the primary task. When visual salience (contrast) or auditory salience (tone intensity) of the alert were increased, participants directed their gaze to the alert more quickly. This confirms that more salient alerts attract attention more efficiently. Increasing auditory salience yielded quicker responses for the alert and primary tasks, apparently confirming faster responses altogether. However, increasing visual salience did not yield similar benefits: instead, it increased the time between fixating the alert and responding, as high-salience alerts interfered with alert-task execution. Such task interference by high-salience alert-signals counteracts their more efficient attentional guidance. The design of alert signals must be adapted to a "sweet spot" that optimizes this stimulus-dependent trade-off between maximally rapid attentional orienting and minimal task interference.
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Affiliation(s)
- Wolfgang Einhäuser
- Physics of Cognition Group, Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany.
| | - Christiane R Neubert
- Cognitive Systems Lab, Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
| | - Sabine Grimm
- Physics of Cognition Group, Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
- BioCog - Cognitive and Biological Psychology, Institute of Psychology, Leipzig University, Leipzig, Germany
| | - Alexandra Bendixen
- Cognitive Systems Lab, Institute of Physics, Chemnitz University of Technology, Chemnitz, Germany
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3
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Tachmatzidou O, Vatakis A. Attention and schema violations of real world scenes differentially modulate time perception. Sci Rep 2023; 13:10002. [PMID: 37340029 DOI: 10.1038/s41598-023-37030-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 06/14/2023] [Indexed: 06/22/2023] Open
Abstract
In the real world, object arrangement follows a number of rules. Some of the rules pertain to the spatial relations between objects and scenes (i.e., syntactic rules) and others about the contextual relations (i.e., semantic rules). Research has shown that violation of semantic rules influences interval timing with the duration of scenes containing such violations to be overestimated as compared to scenes with no violations. However, no study has yet investigated whether both semantic and syntactic violations can affect timing in the same way. Furthermore, it is unclear whether the effect of scene violations on timing is due to attentional or other cognitive accounts. Using an oddball paradigm and real-world scenes with or without semantic and syntactic violations, we conducted two experiments on whether time dilation will be obtained in the presence of any type of scene violation and the role of attention in any such effect. Our results from Experiment 1 showed that time dilation indeed occurred in the presence of syntactic violations, while time compression was observed for semantic violations. In Experiment 2, we further investigated whether these estimations were driven by attentional accounts, by utilizing a contrast manipulation of the target objects. The results showed that an increased contrast led to duration overestimation for both semantic and syntactic oddballs. Together, our results indicate that scene violations differentially affect timing due to violation processing differences and, moreover, their effect on timing seems to be sensitive to attentional manipulations such as target contrast.
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Affiliation(s)
- Ourania Tachmatzidou
- Multisensory and Temporal Processing Laboratory (MultiTimeLab), Department of Psychology, Panteion University of Social and Political Sciences, 136 Syngrou Ave., 17671, Athens, Greece
| | - Argiro Vatakis
- Multisensory and Temporal Processing Laboratory (MultiTimeLab), Department of Psychology, Panteion University of Social and Political Sciences, 136 Syngrou Ave., 17671, Athens, Greece.
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4
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Herrera-Esposito D, Coen-Cagli R, Gomez-Sena L. Flexible contextual modulation of naturalistic texture perception in peripheral vision. J Vis 2021; 21:1. [PMID: 33393962 PMCID: PMC7794279 DOI: 10.1167/jov.21.1.1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Accepted: 12/01/2020] [Indexed: 11/24/2022] Open
Abstract
Peripheral vision comprises most of our visual field, and is essential in guiding visual behavior. Its characteristic capabilities and limitations, which distinguish it from foveal vision, have been explained by the most influential theory of peripheral vision as the product of representing the visual input using summary statistics. Despite its success, this account may provide a limited understanding of peripheral vision, because it neglects processes of perceptual grouping and segmentation. To test this hypothesis, we studied how contextual modulation, namely the modulation of the perception of a stimulus by its surrounds, interacts with segmentation in human peripheral vision. We used naturalistic textures, which are directly related to summary-statistics representations. We show that segmentation cues affect contextual modulation, and that this is not captured by our implementation of the summary-statistics model. We then characterize the effects of different texture statistics on contextual modulation, providing guidance for extending the model, as well as for probing neural mechanisms of peripheral vision.
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Affiliation(s)
- Daniel Herrera-Esposito
- Laboratorio de Neurociencias, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
| | - Ruben Coen-Cagli
- Department of Systems and Computational Biology and Dominick P. Purpura Department of Neuroscience, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Leonel Gomez-Sena
- Laboratorio de Neurociencias, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay
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5
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Stuart GW, Yip D, Hogendoorn H. The role of hue in visual search for texture differences: Implications for camouflage design. Vision Res 2020; 176:16-26. [PMID: 32768744 DOI: 10.1016/j.visres.2020.07.008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Revised: 04/16/2020] [Accepted: 07/13/2020] [Indexed: 11/18/2022]
Abstract
The purpose of camouflage is to be inconspicuous against a given background. Colour is an important component of camouflage, and the task of designing a single camouflage pattern for use against multiple different backgrounds is particularly challenging. As it is impossible to match the colour gamut of each background exactly, the question arises which colours from the different backgrounds should be incorporated in a camouflage pattern to achieve optimal concealment. Here, we used a visual search paradigm to address this question. Observers searched multi-coloured continuous textures for target regions defined by either the presence or absence of additional hues. Targets could be either a combination of five hues against a four-hued background ("patches"), or a combination of four hues against a five-hued background ("holes"). In Experiment 1, a search asymmetry was observed for the different targets, as observers were less accurate and slower at detecting holes than patches. Additionally, we observed a linear separability effect: search for a target was more difficult when the hue that defined the target was within the gamut of distractor colours (e.g. orange amongst reds and yellows). In Experiment 2, we further investigated "hole" targets designed for two different backgrounds and found that optimal concealment against both backgrounds was achieved by including intermediate colours that represented a compromise between the common colours and the unique colours of each background. The findings provide insights into how search asymmetries can be extended to complex texture properties and help inform the design process of camouflage for multiple backgrounds.
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Affiliation(s)
- Geoffrey W Stuart
- Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Australia.
| | - Dominic Yip
- Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Australia
| | - Hinze Hogendoorn
- Melbourne School of Psychological Sciences, Faculty of Medicine, Dentistry and Health Sciences, The University of Melbourne, Australia
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6
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Lancry-Dayan OC, Kupershmidt G, Pertzov Y. Been there, seen that, done that: Modification of visual exploration across repeated exposures. J Vis 2020; 19:2. [PMID: 31585463 DOI: 10.1167/19.12.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
The underlying factors that determine gaze position are a central topic in visual cognitive research. Traditionally, studies emphasized the interaction between the low-level properties of an image and gaze position. Later studies examined the influence of the semantic properties of an image. These studies explored gaze behavior during a single presentation, thus ignoring the impact of familiarity. Sparse evidence suggested that across repetitive exposures, gaze exploration attenuates but the correlation between gaze position and the low-level features of the image remains stable. However, these studies neglected two fundamental issues: (a) repeated scenes are displayed later in the testing session, such that exploration attenuation could be a result of lethargy, and (b) even if these effects are related to familiarity, are they based on a verbatim familiarity with the image, or on high-level familiarity with the gist of the scene? We investigated these issues by exposing participants to a sequence of images, some of them repeated across blocks. We found fewer, longer fixations as familiarity increased, along with shorter saccades and decreased gaze allocation towards semantically meaningful regions. These effects could not be ascribed to tonic fatigue, since they did not manifest for images that changed across blocks. Moreover, there was no attenuation of gaze behavior when participants observed a flipped version of the familiar images, suggesting that gist familiarity is not sufficient for eliciting these effects. These findings contribute to the literature on memory-guided gaze behavior and provide novel insights into the mechanism underlying the visual exploration of familiar environments.
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Affiliation(s)
- Oryah C Lancry-Dayan
- Department of Psychology, Hebrew University of Jerusalem, Mount Scopus, Jerusalem, Israel
| | - Ganit Kupershmidt
- Department of Psychology, Hebrew University of Jerusalem, Mount Scopus, Jerusalem, Israel
| | - Yoni Pertzov
- Department of Psychology, Hebrew University of Jerusalem, Mount Scopus, Jerusalem, Israel
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Wegner-Clemens K, Rennig J, Magnotti JF, Beauchamp MS. Using principal component analysis to characterize eye movement fixation patterns during face viewing. J Vis 2019; 19:2. [PMID: 31689715 PMCID: PMC6833982 DOI: 10.1167/19.13.2] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Accepted: 08/23/2019] [Indexed: 01/22/2023] Open
Abstract
Human faces contain dozens of visual features, but viewers preferentially fixate just two of them: the eyes and the mouth. Face-viewing behavior is usually studied by manually drawing regions of interest (ROIs) on the eyes, mouth, and other facial features. ROI analyses are problematic as they require arbitrary experimenter decisions about the location and number of ROIs, and they discard data because all fixations within each ROI are treated identically and fixations outside of any ROI are ignored. We introduce a data-driven method that uses principal component analysis (PCA) to characterize human face-viewing behavior. All fixations are entered into a PCA, and the resulting eigenimages provide a quantitative measure of variability in face-viewing behavior. In fixation data from 41 participants viewing four face exemplars under three stimulus and task conditions, the first principal component (PC1) separated the eye and mouth regions of the face. PC1 scores varied widely across participants, revealing large individual differences in preference for eye or mouth fixation, and PC1 scores varied by condition, revealing the importance of behavioral task in determining fixation location. Linear mixed effects modeling of the PC1 scores demonstrated that task condition accounted for 41% of the variance, individual differences accounted for 28% of the variance, and stimulus exemplar for less than 1% of the variance. Fixation eigenimages provide a useful tool for investigating the relative importance of the different factors that drive human face-viewing behavior.
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Affiliation(s)
- Kira Wegner-Clemens
- Department of Neurosurgery and Core for Advanced MRI, Baylor College of Medicine, Houston, TX
| | - Johannes Rennig
- Department of Neurosurgery and Core for Advanced MRI, Baylor College of Medicine, Houston, TX
| | - John F Magnotti
- Department of Neurosurgery and Core for Advanced MRI, Baylor College of Medicine, Houston, TX
| | - Michael S Beauchamp
- Department of Neurosurgery and Core for Advanced MRI, Baylor College of Medicine, Houston, TX
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8
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Juarez MC, Ishii L, Nellis JC, Bater K, Huynh PP, Fung N, Darrach H, Russell JO, Ishii M. Objectively measuring social attention of thyroid neck scars and transoral surgery using eye tracking. Laryngoscope 2019; 129:2789-2794. [DOI: 10.1002/lary.27933] [Citation(s) in RCA: 47] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Revised: 02/17/2019] [Accepted: 02/25/2019] [Indexed: 12/31/2022]
Affiliation(s)
| | - Lisa Ishii
- Division of Facial Plastic and Reconstructive Surgery, Department of Otolaryngology–Head and Neck SurgeryJohns Hopkins University School of Medicine Baltimore Maryland U.S.A
- Department of Otolaryngology–Head and Neck SurgeryJohns Hopkins University School of Medicine Baltimore Maryland U.S.A
| | - Jason C. Nellis
- Department of Otolaryngology–Head and Neck SurgeryJohns Hopkins University School of Medicine Baltimore Maryland U.S.A
| | - Kristin Bater
- Johns Hopkins School of Medicine Baltimore Maryland U.S.A
| | | | - Nicholas Fung
- Johns Hopkins School of Medicine Baltimore Maryland U.S.A
| | - Halley Darrach
- Johns Hopkins School of Medicine Baltimore Maryland U.S.A
| | - Jonathon O. Russell
- Department of Otolaryngology–Head and Neck SurgeryJohns Hopkins University School of Medicine Baltimore Maryland U.S.A
- Division of Head and Neck Endocrine Surgery, Department of Otolaryngology–Head and Neck SurgeryJohns Hopkins University School of Medicine Baltimore Maryland U.S.A
| | - Masaru Ishii
- Department of Otolaryngology–Head and Neck SurgeryJohns Hopkins University School of Medicine Baltimore Maryland U.S.A
- Division of Rhinology, Department of Otolaryngology–Head and Neck SurgeryJohns Hopkins University School of Medicine Baltimore Maryland U.S.A
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9
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Barry AE, Padon AA, Whiteman SD, Hicks KK, Carreon AK, Crowell JR, Willingham KL, Merianos AL. Alcohol Advertising on Social Media: Examining the Content of Popular Alcohol Brands on Instagram. Subst Use Misuse 2018; 53:2413-2420. [PMID: 29889647 DOI: 10.1080/10826084.2018.1482345] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
Abstract
BACKGROUND There is considerable evidence that exposure to alcohol marketing increases the likelihood of adolescents initiating and engaging in alcohol consumption. There is a paucity of research, however, specifically examining industry generated alcohol marketing occurring on social media/networking platforms. OBJECTIVE The purpose of this investigation was to analyze the content of promotional advertisements by alcohol brands on Instagram. METHODS For a 30-day period, Instagram profiles of 15 distinct alcohol brands were examined. Pictorial posts/updates from each profile were screen captured and individually documented. Approximately 184 distinct posts constituted our final sample. The Content Appealing to Youth Index was independently employed by two raters to assess each post. For each characteristic, Cohen's Kappa measures, and associated 95% confidence intervals, were calculated. Descriptive statistics were performed. RESULTS Posts increased throughout the week and peaked on Thursday and Friday. The production value of the posts examined was generally high, frequently featuring color, texture, shine, contrast, faces, and action. Character appeals and use of youth-oriented genres were uncommon. Many of the posts used product appeals and physical benefits to consumption. The posts also emphasized the following rewarding appeal characteristics: positive emotional experiences, achievement, individuality, and camaraderie. The most commonly coded risk-related feature was inappropriate use. Conclusions/Importance: This investigation represents an initial attempt to provide insights into the content alcohol brands are including in their promotional materials on social networking sites.
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Affiliation(s)
- Adam E Barry
- a Department of Health & Kinesiology , Texas A&M University , College Station , Texas , USA
| | - Alisa A Padon
- b Annenberg School for Communication , University of Pennsylvania , Philadelphia , Pennsylvania , USA
| | - Shawn D Whiteman
- c Department of Family, Consumer, and Human Development , Utah State University , Logan , Utah , USA
| | - Kristen K Hicks
- d Department of Nutrition and Food Science , Texas A&M University , College Station , Texas , USA
| | - Amie K Carreon
- a Department of Health & Kinesiology , Texas A&M University , College Station , Texas , USA
| | - Jarrett R Crowell
- a Department of Health & Kinesiology , Texas A&M University , College Station , Texas , USA
| | - Kristen L Willingham
- a Department of Health & Kinesiology , Texas A&M University , College Station , Texas , USA
| | - Ashley L Merianos
- e School of Human Services , University of Cincinnati , Cincinnati , Ohio , USA
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10
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Osadebey ME, Pedersen M, Arnold DL, Wendel-Mitoraj KE, Alzheimer's Disease Neuroimaging Initiative FT. Standardized quality metric system for structural brain magnetic resonance images in multi-center neuroimaging study. BMC Med Imaging 2018; 18:31. [PMID: 30223797 PMCID: PMC6142697 DOI: 10.1186/s12880-018-0266-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 07/31/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Multi-site neuroimaging offer several benefits and poses tough challenges in the drug development process. Although MRI protocol and clinical guidelines developed to address these challenges recommend the use of good quality images, reliable assessment of image quality is hampered by the several shortcomings of existing techniques. METHODS Given a test image two feature images are extracted. They are grayscale and contrast feature images. Four binary images are generated by setting four different global thresholds on the feature images. Image quality is predicted by measuring the structural similarity between appropriate pairs of binary images. The lower and upper limits of the quality index are 0 and 1. Quality prediction is based on four quality attributes; luminance contrast, texture, texture contrast and lightness. RESULTS Performance evaluation on test data from three multi-site clinical trials show good objective quality evaluation across MRI sequences, levels of distortion and quality attributes. Correlation with subjective evaluation by human observers is ≥ 0.6. CONCLUSION The results are promising for the evaluation of MRI protocols, specifically the standardization of quality index, designed to overcome the challenges encountered in multi-site clinical trials.
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Affiliation(s)
- Michael E Osadebey
- NeuroRx Research Inc, Montreal, 3575 Parc Avenue, Suite # 5322, Montreal, Quebec, H2X 3P9, Canada
| | - Marius Pedersen
- Department of Computer Science, Norwegian University of Science and Technology, Teknologivegen 22, Gjøvik, N-2815, Norway.
| | - Douglas L Arnold
- Montreal Neurological Institute and Hospital, McGill University, 3801 University St, Montreal, Quebec, H3A 2B4, Canada
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Ahmadlou M, Tafreshiha A, Heimel JA. Visual Cortex Limits Pop-Out in the Superior Colliculus of Awake Mice. Cereb Cortex 2018; 27:5772-5783. [PMID: 29029071 PMCID: PMC5939206 DOI: 10.1093/cercor/bhx254] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2017] [Indexed: 12/25/2022] Open
Abstract
We detect objects more readily if they differ from their surroundings in motion, color, or texture. This increased saliency is thought to be related to increased responses in the visual cortex. The superior colliculus is another brain area involved in vision and especially in directing gaze and attention. In this study, we show that differences in texture orientation also increase responses in the superficial layers of the superior colliculus that receive retinal and cortical input. We found that gratings evoke more neural response when surrounded by orthogonal gratings than when surrounded by parallel gratings, particularly in the awake mouse. This pop-out is not originating from the visual cortex, and silencing visual cortex increased the relative difference in response. A model shows that this can result from retinotopically matched excitation from visual cortex to the superior colliculus. We suggest that the perceptual saliency of a stimulus differing from its surround in a low-level feature like grating orientation could depend on visual processing in the superior colliculus.
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Affiliation(s)
- Mehran Ahmadlou
- Department of Cortical Structure and Function, The Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA Amsterdam, The Netherlands
| | - Azadeh Tafreshiha
- Department of Cortical Structure and Function, The Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA Amsterdam, The Netherlands
| | - J Alexander Heimel
- Department of Cortical Structure and Function, The Netherlands Institute for Neuroscience, Royal Netherlands Academy of Arts and Sciences (KNAW), Meibergdreef 47, 1105 BA Amsterdam, The Netherlands
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12
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Neri P. Object segmentation controls image reconstruction from natural scenes. PLoS Biol 2017; 15:e1002611. [PMID: 28827801 PMCID: PMC5565198 DOI: 10.1371/journal.pbio.1002611] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2016] [Accepted: 07/25/2017] [Indexed: 11/22/2022] Open
Abstract
The structure of the physical world projects images onto our eyes. However, those images are often poorly representative of environmental structure: well-defined boundaries within the eye may correspond to irrelevant features of the physical world, while critical features of the physical world may be nearly invisible at the retinal projection. The challenge for the visual cortex is to sort these two types of features according to their utility in ultimately reconstructing percepts and interpreting the constituents of the scene. We describe a novel paradigm that enabled us to selectively evaluate the relative role played by these two feature classes in signal reconstruction from corrupted images. Our measurements demonstrate that this process is quickly dominated by the inferred structure of the environment, and only minimally controlled by variations of raw image content. The inferential mechanism is spatially global and its impact on early visual cortex is fast. Furthermore, it retunes local visual processing for more efficient feature extraction without altering the intrinsic transduction noise. The basic properties of this process can be partially captured by a combination of small-scale circuit models and large-scale network architectures. Taken together, our results challenge compartmentalized notions of bottom-up/top-down perception and suggest instead that these two modes are best viewed as an integrated perceptual mechanism. Biological vision is designed to discover the structure of the environment around us. To do this, it relies on ambiguous and often misleading information from the eyes: the boundary of a critical object may be invisible against a background of similar appearance, and may be overlooked in favour of the sharp contour projected by an irrelevant shadow. It remains unclear how human vision sorts different image features according to their relevance to the layout of objects within the scene. We demonstrate that vision achieves this goal via a specialized perceptual system for object segmentation that is one and the same with the feature extraction system: immediately after information is relayed to cortex by the eyes, the process of reconstructing image content from local features is controlled by a dedicated inferential mechanism that attempts to recover the underlying environmental structure; perception is quickly organized around the operation of this mechanism, which becomes the primary contextual influence on image reconstruction. The integrated nature of this perceptual mechanism defies current notions of separate top-down and bottom-up processes, offering a fresh view of how human vision operates on natural signals.
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Affiliation(s)
- Peter Neri
- Laboratoire des Systèmes Perceptifs, Département d'études cognitives, Ecole Normale Supérieure, PSL Research University, CNRS, Paris, France
- * E-mail:
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13
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Abstract
Attention and eye movements provide a window into the selective processing of visual information. Evidence suggests that selection is influenced by various factors and is not always under the strategic control of the observer. The aims of this tutorial review are to give a brief introduction to eye movements and attention and to outline the conditions that help determine control. Evidence suggests that the ability to establish control depends on the complexity of the display as well as the point in time at which selection occurs. Stimulus-driven selection is more probable in simple displays than in complex natural scenes, but it critically depends on the timing of the response: Salience determines selection only when responses are triggered quickly following display presentation, and plays no role in longer-latency responses. The time course of selection is also important for the relationship between attention and eye movements. Specifically, attention and eye movements appear to act independently when oculomotor selection is quick, whereas attentional processes are able to influence oculomotor control when saccades are triggered only later in time. This relationship may also be modulated by whether the eye movement is controlled in a voluntary or an involuntary manner. To conclude, we present evidence that shows that visual control is limited in flexibility and that the mechanisms of selection are constrained by context and time. The outcome of visual selection changes with the situational context, and knowing the constraints of control is necessary to understanding when and how visual selection is truly controlled by the observer.
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14
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Hua Y, Yang M, Zhao Z, Zhou R, Cai A. On semantic-instructed attention: From video eye-tracking dataset to memory-guided probabilistic saliency model. Neurocomputing 2015. [DOI: 10.1016/j.neucom.2015.05.033] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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15
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Nuthmann A, Einhäuser W. A new approach to modeling the influence of image features on fixation selection in scenes. Ann N Y Acad Sci 2015; 1339:82-96. [PMID: 25752239 PMCID: PMC4402003 DOI: 10.1111/nyas.12705] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
Which image characteristics predict where people fixate when memorizing natural images? To answer this question, we introduce a new analysis approach that combines a novel scene-patch analysis with generalized linear mixed models (GLMMs). Our method allows for (1) directly describing the relationship between continuous feature value and fixation probability, and (2) assessing each feature's unique contribution to fixation selection. To demonstrate this method, we estimated the relative contribution of various image features to fixation selection: luminance and luminance contrast (low-level features); edge density (a mid-level feature); visual clutter and image segmentation to approximate local object density in the scene (higher-level features). An additional predictor captured the central bias of fixation. The GLMM results revealed that edge density, clutter, and the number of homogenous segments in a patch can independently predict whether image patches are fixated or not. Importantly, neither luminance nor contrast had an independent effect above and beyond what could be accounted for by the other predictors. Since the parcellation of the scene and the selection of features can be tailored to the specific research question, our approach allows for assessing the interplay of various factors relevant for fixation selection in scenes in a powerful and flexible manner.
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Affiliation(s)
- Antje Nuthmann
- Psychology Department, School of Philosophy, Psychology and Language Sciences, University of EdinburghUnited Kingdom
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Overt attention in natural scenes: Objects dominate features. Vision Res 2015; 107:36-48. [DOI: 10.1016/j.visres.2014.11.006] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Revised: 11/04/2014] [Accepted: 11/10/2014] [Indexed: 11/18/2022]
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17
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Schmid AM, Victor JD. Possible functions of contextual modulations and receptive field nonlinearities: pop-out and texture segmentation. Vision Res 2014; 104:57-67. [PMID: 25064441 PMCID: PMC4253048 DOI: 10.1016/j.visres.2014.07.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2014] [Revised: 06/05/2014] [Accepted: 07/14/2014] [Indexed: 10/25/2022]
Abstract
When analyzing a visual image, the brain has to achieve several goals quickly. One crucial goal is to rapidly detect parts of the visual scene that might be behaviorally relevant, while another one is to segment the image into objects, to enable an internal representation of the world. Both of these processes can be driven by local variations in any of several image attributes such as luminance, color, and texture. Here, focusing on texture defined by local orientation, we propose that the two processes are mediated by separate mechanisms that function in parallel. More specifically, differences in orientation can cause an object to "pop out" and attract visual attention, if its orientation differs from that of the surrounding objects. Differences in orientation can also signal a boundary between objects and therefore provide useful information for image segmentation. We propose that contextual response modulations in primary visual cortex (V1) are responsible for orientation pop-out, while a different kind of receptive field nonlinearity in secondary visual cortex (V2) is responsible for orientation-based texture segmentation. We review a recent experiment that led us to put forward this hypothesis along with other research literature relevant to this notion.
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Affiliation(s)
- Anita M Schmid
- Brain and Mind Research Institute, Division of Systems Neurology and Neuroscience, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA.
| | - Jonathan D Victor
- Brain and Mind Research Institute, Division of Systems Neurology and Neuroscience, Weill Cornell Medical College, 1300 York Avenue, New York, NY 10065, USA.
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18
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Platzer C, Bröder A, Heck DW. Deciding with the eye: how the visually manipulated accessibility of information in memory influences decision behavior. Mem Cognit 2014; 42:595-608. [PMID: 24217893 PMCID: PMC4024153 DOI: 10.3758/s13421-013-0380-z] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Decision situations are typically characterized by uncertainty: Individuals do not know the values of different options on a criterion dimension. For example, consumers do not know which is the healthiest of several products. To make a decision, individuals can use information about cues that are probabilistically related to the criterion dimension, such as sugar content or the concentration of natural vitamins. In two experiments, we investigated how the accessibility of cue information in memory affects which decision strategy individuals rely on. The accessibility of cue information was manipulated by means of a newly developed paradigm, the spatial-memory-cueing paradigm, which is based on a combination of the looking-at-nothing phenomenon and the spatial-cueing paradigm. The results indicated that people use different decision strategies, depending on the validity of easily accessible information. If the easily accessible information is valid, people stop information search and decide according to a simple take-the-best heuristic. If, however, information that comes to mind easily has a low predictive validity, people are more likely to integrate all available cue information in a compensatory manner.
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Affiliation(s)
- Christine Platzer
- School of Social Sciences, University of Mannheim, Mannheim, Germany,
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19
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Farnand SP, Fairchild MD. Designing pictorial stimuli for perceptual experiments. APPLIED OPTICS 2014; 53:C72-C82. [PMID: 24921892 DOI: 10.1364/ao.53.000c72] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2013] [Accepted: 03/19/2014] [Indexed: 06/03/2023]
Abstract
The effects of design decisions in the development of systems that generate images for human consumption, such as cameras and displays, are often evaluated using real-world images. However, human observers can react differently to complex pictorial stimuli over the course of a lengthy experiment. This study was conducted to develop understanding of the optimal design of pictorial stimuli for effective and efficient perceptual experiments. The goals were to understand the impact of image content on visual attention and consistency of experimental results and apply this understanding to develop guidelines for pictorial target design for perceptual image comparison experiments. The efficacy of the proposed guidelines was evaluated. While the fixation consistency results were generally as expected, fixation consistency did not always equate to experimental response consistency. Along with scene complexity, the image modifications and the difficulty of the image equivalency decisions played a role in the experimental response.
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20
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Onat S, Açık A, Schumann F, König P. The contributions of image content and behavioral relevancy to overt attention. PLoS One 2014; 9:e93254. [PMID: 24736751 PMCID: PMC3988016 DOI: 10.1371/journal.pone.0093254] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2013] [Accepted: 03/04/2014] [Indexed: 11/19/2022] Open
Abstract
During free-viewing of natural scenes, eye movements are guided by bottom-up factors inherent to the stimulus, as well as top-down factors inherent to the observer. The question of how these two different sources of information interact and contribute to fixation behavior has recently received a lot of attention. Here, a battery of 15 visual stimulus features was used to quantify the contribution of stimulus properties during free-viewing of 4 different categories of images (Natural, Urban, Fractal and Pink Noise). Behaviorally relevant information was estimated in the form of topographical interestingness maps by asking an independent set of subjects to click at image regions that they subjectively found most interesting. Using a Bayesian scheme, we computed saliency functions that described the probability of a given feature to be fixated. In the case of stimulus features, the precise shape of the saliency functions was strongly dependent upon image category and overall the saliency associated with these features was generally weak. When testing multiple features jointly, a linear additive integration model of individual saliencies performed satisfactorily. We found that the saliency associated with interesting locations was much higher than any low-level image feature and any pair-wise combination thereof. Furthermore, the low-level image features were found to be maximally salient at those locations that had already high interestingness ratings. Temporal analysis showed that regions with high interestingness ratings were fixated as early as the third fixation following stimulus onset. Paralleling these findings, fixation durations were found to be dependent mainly on interestingness ratings and to a lesser extent on the low-level image features. Our results suggest that both low- and high-level sources of information play a significant role during exploration of complex scenes with behaviorally relevant information being more effective compared to stimulus features.
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Affiliation(s)
- Selim Onat
- Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany
- * E-mail:
| | - Alper Açık
- Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany
| | - Frank Schumann
- Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany
| | - Peter König
- Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany
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't Hart BM, Schmidt HCEF, Klein-Harmeyer I, Einhäuser W. Attention in natural scenes: contrast affects rapid visual processing and fixations alike. Philos Trans R Soc Lond B Biol Sci 2013; 368:20130067. [PMID: 24018728 PMCID: PMC3758209 DOI: 10.1098/rstb.2013.0067] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
For natural scenes, attention is frequently quantified either by performance during rapid presentation or by gaze allocation during prolonged viewing. Both paradigms operate on different time scales, and tap into covert and overt attention, respectively. To compare these, we ask some observers to detect targets (animals/vehicles) in rapid sequences, and others to freely view the same target images for 3 s, while their gaze is tracked. In some stimuli, the target's contrast is modified (increased/decreased) and its background modified either in the same or in the opposite way. We find that increasing target contrast relative to the background increases fixations and detection alike, whereas decreasing target contrast and simultaneously increasing background contrast has little effect. Contrast increase for the whole image (target + background) improves detection, decrease worsens detection, whereas fixation probability remains unaffected by whole-image modifications. Object-unrelated local increase or decrease of contrast attracts gaze, but less than actual objects, supporting a precedence of objects over low-level features. Detection and fixation probability are correlated: the more likely a target is detected in one paradigm, the more likely it is fixated in the other. Hence, the link between overt and covert attention, which has been established in simple stimuli, transfers to more naturalistic scenarios.
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Niu Y, Todd RM, Anderson AK. Affective salience can reverse the effects of stimulus-driven salience on eye movements in complex scenes. Front Psychol 2012; 3:336. [PMID: 23055990 PMCID: PMC3457078 DOI: 10.3389/fpsyg.2012.00336] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Accepted: 08/21/2012] [Indexed: 11/13/2022] Open
Abstract
In natural vision both stimulus features and cognitive/affective factors influence an observer's attention. However, the relationship between stimulus-driven ("bottom-up") and cognitive/affective ("top-down") factors remains controversial: Can affective salience counteract strong visual stimulus signals and shift attention allocation irrespective of bottom-up features? Is there any difference between negative and positive scenes in terms of their influence on attention deployment? Here we examined the impact of affective factors on eye movement behavior, to understand the competition between visual stimulus-driven salience and affective salience and how they affect gaze allocation in complex scene viewing. Building on our previous research, we compared predictions generated by a visual salience model with measures indexing participant-identified emotionally meaningful regions of each image. To examine how eye movement behavior differs for negative, positive, and neutral scenes, we examined the influence of affective salience in capturing attention according to emotional valence. Taken together, our results show that affective salience can override stimulus-driven salience and overall emotional valence can determine attention allocation in complex scenes. These findings are consistent with the hypothesis that cognitive/affective factors play a dominant role in active gaze control.
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Affiliation(s)
- Yaqing Niu
- Affect and Cognition Laboratory, Department of Psychology, University of Toronto Toronto, ON, Canada
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23
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Kaspar K, König P. Overt attention and context factors: the impact of repeated presentations, image type, and individual motivation. PLoS One 2011; 6:e21719. [PMID: 21750726 PMCID: PMC3130043 DOI: 10.1371/journal.pone.0021719] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2010] [Accepted: 06/09/2011] [Indexed: 11/18/2022] Open
Abstract
The present study investigated the dynamic of the attention focus during observation of different categories of complex scenes and simultaneous consideration of individuals' memory and motivational state. We repeatedly presented four types of complex visual scenes in a pseudo-randomized order and recorded eye movements. Subjects were divided into groups according to their motivational disposition in terms of action orientation and individual rating of scene interest. Statistical analysis of eye-tracking data revealed that the attention focus successively became locally expressed by increasing fixation duration; decreasing saccade length, saccade frequency, and single subject's fixation distribution over images; and increasing inter-subject variance of fixation distributions. The validity of these results was supported by verbal reports. This general tendency was weaker for the group of subjects who rated the image set as interesting as compared to the other group. Additionally, effects were partly mediated by subjects' motivational disposition. Finally, we found a generally strong impact of image type on eye movement parameters. We conclude that motivational tendencies linked to personality as well as individual preferences significantly affected viewing behaviour. Hence, it is important and fruitful to consider inter-individual differences on the level of motivation and personality traits within investigations of attention processes. We demonstrate that future studies on memory's impact on overt attention have to deal appropriately with several aspects that had been out of the research focus until now.
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Affiliation(s)
- Kai Kaspar
- Institute of Cognitive Science, University of Osnabrück, Osnabrück, Germany.
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24
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Godoy A, Ishii M, Byrne PJ, Boahene KDO, Encarnacion CO, Ishii LE. The straight truth: measuring observer attention to the crooked nose. Laryngoscope 2011; 121:937-41. [PMID: 21520106 DOI: 10.1002/lary.21733] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVES/HYPOTHESIS Quantify attentional distraction to crooked noses pre- and postoperatively as compared with normal noses by using an established metric of attention in a pilot study. STUDY DESIGN Prospective, randomized, controlled experiment with crossover. METHODS An eye-tracker system was used to record the eye-movement patterns, called scanpaths, of 40 naive observers gazing at pictures of faces with crooked noses preoperatively or postoperatively and pictures of faces without a crooked nose included as "normals." The fixation durations within the nasal area for each group of faces presented were compared. RESULTS A mixed-design univariate analysis of variance was performed to test the hypothesis that mean fixation times in the nasal region varied by face group. The results were highly statistically significant, F(2,116) = 20.28, P = .000, η(2) = 0.029. Marginal means were calculated for each nasal area of interest group with confidence intervals (normal, 2.32 [2.26-2.38]; preoperative, 2.66 [2.58-2.75]; postoperative, 2.43 [2.35-2.51]). Post hoc testing with Bonferroni correction for three comparisons showed differences between the normal and preoperative groups (χ(2) 41.38, P = .000) and between the preoperative and postoperative groups (χ(2) 14.41, P = .000) but not between the normal and postoperative groups (χ(2) 4.19, P = .12). CONCLUSIONS There were highly statistically significant differences in attention paid to the nasal area of crooked noses preoperatively and postoperatively, and there were no differences in attention to the nasal area between the postoperative noses and the normal noses. This represents a novel method for objectively evaluating attention and success of surgical procedures to minimize the appearance of deformities.
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Affiliation(s)
- Andres Godoy
- Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland, USA
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25
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Frey HP, Wirz K, Willenbockel V, Betz T, Schreiber C, Troscianko T, König P. Beyond correlation: do color features influence attention in rainforest? Front Hum Neurosci 2011; 5:36. [PMID: 21519395 PMCID: PMC3079176 DOI: 10.3389/fnhum.2011.00036] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2010] [Accepted: 03/24/2011] [Indexed: 11/22/2022] Open
Abstract
Recent research indicates a direct relationship between low-level color features and visual attention under natural conditions. However, the design of these studies allows only correlational observations and no inference about mechanisms. Here we go a step further to examine the nature of the influence of color features on overt attention in an environment in which trichromatic color vision is advantageous. We recorded eye-movements of color-normal and deuteranope human participants freely viewing original and modified rainforest images. Eliminating red–green color information dramatically alters fixation behavior in color-normal participants. Changes in feature correlations and variability over subjects and conditions provide evidence for a causal effect of red–green color-contrast. The effects of blue–yellow contrast are much smaller. However, globally rotating hue in color space in these images reveals a mechanism analyzing color-contrast invariant of a specific axis in color space. Surprisingly, in deuteranope participants we find significantly elevated red–green contrast at fixation points, comparable to color-normal participants. Temporal analysis indicates that this is due to compensatory mechanisms acting on a slower time scale. Taken together, our results suggest that under natural conditions red–green color information contributes to overt attention at a low-level (bottom-up). Nevertheless, the results of the image modifications and deuteranope participants indicate that evaluation of color information is done in a hue-invariant fashion.
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Affiliation(s)
- Hans-Peter Frey
- Department of Neurobiopsychology, Institute of Cognitive Science, University of Osnabrück Osnabrück, Germany
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26
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Ho-Phuoc T, Guyader N, Guérin-Dugué A. A Functional and Statistical Bottom-Up Saliency Model to Reveal the Relative Contributions of Low-Level Visual Guiding Factors. Cognit Comput 2010. [DOI: 10.1007/s12559-010-9078-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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27
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Kollmorgen S, Nortmann N, Schröder S, König P. Influence of low-level stimulus features, task dependent factors, and spatial biases on overt visual attention. PLoS Comput Biol 2010; 6:e1000791. [PMID: 20502672 PMCID: PMC2873902 DOI: 10.1371/journal.pcbi.1000791] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2010] [Accepted: 04/21/2010] [Indexed: 11/18/2022] Open
Abstract
Visual attention is thought to be driven by the interplay between low-level visual features and task dependent information content of local image regions, as well as by spatial viewing biases. Though dependent on experimental paradigms and model assumptions, this idea has given rise to varying claims that either bottom-up or top-down mechanisms dominate visual attention. To contribute toward a resolution of this discussion, here we quantify the influence of these factors and their relative importance in a set of classification tasks. Our stimuli consist of individual image patches (bubbles). For each bubble we derive three measures: a measure of salience based on low-level stimulus features, a measure of salience based on the task dependent information content derived from our subjects' classification responses and a measure of salience based on spatial viewing biases. Furthermore, we measure the empirical salience of each bubble based on our subjects' measured eye gazes thus characterizing the overt visual attention each bubble receives. A multivariate linear model relates the three salience measures to overt visual attention. It reveals that all three salience measures contribute significantly. The effect of spatial viewing biases is highest and rather constant in different tasks. The contribution of task dependent information is a close runner-up. Specifically, in a standardized task of judging facial expressions it scores highly. The contribution of low-level features is, on average, somewhat lower. However, in a prototypical search task, without an available template, it makes a strong contribution on par with the two other measures. Finally, the contributions of the three factors are only slightly redundant, and the semi-partial correlation coefficients are only slightly lower than the coefficients for full correlations. These data provide evidence that all three measures make significant and independent contributions and that none can be neglected in a model of human overt visual attention.
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Affiliation(s)
- Sepp Kollmorgen
- Institute of Neurobiopsychology, University of Osnabrück, Osnabrück, Germany
- Institute of Neuroinformatics, University of Zurich and ETH Zurich, Zurich, Switzerland
| | - Nora Nortmann
- Institute of Neurobiopsychology, University of Osnabrück, Osnabrück, Germany
| | - Sylvia Schröder
- Institute of Neurobiopsychology, University of Osnabrück, Osnabrück, Germany
- Institute of Neuroinformatics, University of Zurich and ETH Zurich, Zurich, Switzerland
- * E-mail:
| | - Peter König
- Institute of Neurobiopsychology, University of Osnabrück, Osnabrück, Germany
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van der Linde I, Rajashekar U, Bovik AC, Cormack LK. Visual memory for fixated regions of natural images dissociates attraction and recognition. Perception 2010; 38:1152-71. [PMID: 19817149 DOI: 10.1068/p6142] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
Recognition memory for fixated regions from briefly viewed full-screen natural images is examined. Low-level image statistics reveal that observers fixated, on average (pooled across images and observers), image regions that possessed greater visual saliency than non-fixated regions, a finding that is robust across multiple fixation indices. Recognition-memory performance indicates that, of the fixation loci tested, observers were adept at recognising those with a particular profile of image statistics; visual saliency was found to be attenuated for unrecognised loci, despite that all regions were freely fixated. Furthermore, although elevated luminance was the local image statistic found to discriminate least between human and random image locations, it was the greatest predictor of recognition-memory performance, demonstrating a dissociation between image features that draw fixations and those that support visual memory. An analysis of corresponding eye movements indicates that image regions fixated via short-distance saccades enjoyed better recognition-memory performance, alluding to a focal rather than ambient mode of processing. Recognised image regions were more likely to have originated from areas evaluated (a posteriori) to have higher fixation density, a numerical metric of local interest. Surprisingly, memory for image regions fixated later in the viewing period exhibited no recency advantage, despite (typically) also being longer in duration, a finding for which a number of explanations are posited.
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Affiliation(s)
- Ian van der Linde
- Department of Computing & Technology, Anglia Ruskin University, Bishops Hall Lane, Chelmsford CM1 1SQ, UK.
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30
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Masciocchi CM, Mihalas S, Parkhurst D, Niebur E. Everyone knows what is interesting: salient locations which should be fixated. J Vis 2009; 9:25.1-22. [PMID: 20053088 DOI: 10.1167/9.11.25] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2009] [Accepted: 09/22/2009] [Indexed: 11/24/2022] Open
Abstract
Most natural scenes are too complex to be perceived instantaneously in their entirety. Observers therefore have to select parts of them and process these parts sequentially. We study how this selection and prioritization process is performed by humans at two different levels. One is the overt attention mechanism of saccadic eye movements in a free-viewing paradigm. The second is a conscious decision process in which we asked observers which points in a scene they considered the most interesting. We find in a very large participant population (more than one thousand) that observers largely agree on which points they consider interesting. Their selections are also correlated with the eye movement pattern of different subjects. Both are correlated with predictions of a purely bottom-up saliency map model. Thus, bottom-up saliency influences cognitive processes as far removed from the sensory periphery as in the conscious choice of what an observer considers interesting.
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31
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Saliency on a natural scene background: effects of color and luminance contrast add linearly. Atten Percept Psychophys 2009; 71:1337-52. [PMID: 19633349 DOI: 10.3758/app.71.6.1337] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In natural vision, shifts in spatial attention are associated with shifts of gaze. Computational models of such overt attention typically use the concept of a saliency map: Normalized maps of center-surround differences are computed for individual stimulus features and added linearly to obtain the saliency map. Although the predictions of such models correlate with fixated locations better than chance, their mechanistic assumptions are less well investigated. Here, we tested one key assumption: Do the effects of different features add linearly or according to a max-type of interaction? We measured the eye position of observers viewing natural stimuli whose luminance contrast and/or color contrast (saturation) increased gradually toward one side. We found that these feature gradients biased fixations toward regions of high contrasts. When two contrast gradients (color and luminance) were superimposed, linear summation of their individual effects predicted their combined effect. This demonstrated that the interaction of color and luminance contrast with respect to human overt attention is--irrespective of the precise model--consistent with the assumption of linearity, but not with a max-type interaction of these features.
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32
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Droll JA, Eckstein MP. Gaze control and memory for objects while walking in a real world environment. VISUAL COGNITION 2009. [DOI: 10.1080/13506280902797125] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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33
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Açik A, Onat S, Schumann F, Einhäuser W, König P. Effects of luminance contrast and its modifications on fixation behavior during free viewing of images from different categories. Vision Res 2009; 49:1541-53. [DOI: 10.1016/j.visres.2009.03.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2008] [Revised: 03/12/2009] [Accepted: 03/12/2009] [Indexed: 11/29/2022]
Affiliation(s)
- Alper Açik
- University of Osnabrück, Institute of Cognitive Science, Osnabrück, Germany.
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34
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Ishii L, Carey J, Byrne P, Zee DS, Ishii M. Measuring attentional bias to peripheral facial deformities. Laryngoscope 2009; 119:459-65. [PMID: 19235748 DOI: 10.1002/lary.20132] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
OBJECTIVES Introduce a novel method for objectively evaluating attentional bias to peripheral facial deformities using an established metric of attention. METHODS The SMI eye-tracker system (SensoMotoric Inc., Boston, MA) was used to record the eye movement patterns, called scanpaths, of eight naïve observers gazing at pictures of faces with or without peripheral surgical deformities. The scanpaths of observers gazing on those novel faces were compared, and the fixation durations for different facial regions were compared between faces. RESULTS There were statistically significant differences in the mean fixation times between the faces considered normal and those considered abnormal (those with an obvious defect). When multivariate analysis of variance was performed with dependent variables total fixation time, fixation time in central triangle, and fixation time in the defect region and the independent variable face, all four tests were highly statistically significant. When univariate analysis of variance was performed to test the hypothesis that defect fixation times varied by face, the results were highly statistically significant (F = 8.79, P = .0003). CONCLUSIONS Observers gazing on faces typically focus their attention on discriminating features, such as eyes, nose, and mouth. The well-established method of eye movement recordings was applied in a novel way to provide quantitative data showing changes in observer gaze patterns to focus on deformities. These gaze patterns are a direct reflection of observer attention. This is the first objective method to quantify the amount of distraction caused by peripheral facial deformities and may provide insight into the perception of facial deformity.
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Affiliation(s)
- Lisa Ishii
- Department of Otolaryngology-Head and Neck Surgery, Division of Facial Plastic and Reconstructive Surgery, Johns Hopkins School of Medicine, Baltimore, Maryland 21287, USA.
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35
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Clarke A, Green P, Chantler M, Emrith K. Visual search for a target against a 1/fβ continuous textured background. Vision Res 2008; 48:2193-203. [DOI: 10.1016/j.visres.2008.06.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2007] [Revised: 06/11/2008] [Accepted: 06/17/2008] [Indexed: 11/26/2022]
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36
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Kim Y, Varshney A. Persuading visual attention through geometry. IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 2008; 14:772-782. [PMID: 18467753 DOI: 10.1109/tvcg.2007.70624] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Artists, illustrators, photographers, and cinematographers have long used the principles of contrast and composition to guide visual attention. In this paper we introduce geometry modification as a tool to persuasively direct visual attention. We build upon recent advances in mesh saliency to develop techniques to alter geometry to elicit greater visual attention. Eye-tracking-based user studies show that our approach successfully guides user attention in a statistically significant manner. Our approach operates directly on geometry, and therefore, produces view-independent results that can be used with existing view-dependent techniques of visual persuasion.
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Affiliation(s)
- Youngmin Kim
- Department of Computer Science and UMIACS, University of Maryland, College Park, MD 20742, USA.
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37
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Frey HP, König P, Einhäuser W. The role of first- and second-order stimulus features for human overt attention. ACTA ACUST UNITED AC 2007; 69:153-61. [PMID: 17557586 DOI: 10.3758/bf03193738] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
When processing complex visual input, human observers sequentially allocate their attention to different subsets of the stimulus. What are the mechanisms and strategies that guide this selection process? We investigated the influence of various stimulus features on human overt attention--that is, attention related to shifts of gaze with natural color images and modified versions thereof. Our experimental modifications, systematic changes of hue across the entire image, influenced only the global appearance of the stimuli, leaving the local features under investigation unaffected. We demonstrated that these modifications consistently reduce the subjective interpretation of a stimulus as "natural" across observers. By analyzing fixations, we found that first-order features, such as luminance contrast, saturation, and color contrast along either of the cardinal axes, correlated to overt attention in the modified images. In contrast, no such correlation was found in unmodified outdoor images. Second-order luminance contrast ("texture contrast") correlated to overt attention in all conditions. However, although none of the second-order color contrasts were correlated to overt attention in unmodified images, one of the second-order color contrasts did exhibit a significant correlation in the modified images. These findings imply, on the one hand, that higher-order bottom-up effects--namely, those of second-order luminance contrast--may partially account for human overt attention. On the other hand, these results also demonstrate that global image properties, which correlate to the subjective impression of a scene being "natural," affect the guidance of human overt attention.
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Affiliation(s)
- Hans-Peter Frey
- Institute of Cognitive Science, Department of Neurobiopsychology, University of Osnabrück, Osnabrück, Germany.
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Kayser C, Nielsen KJ, Logothetis NK. Fixations in natural scenes: interaction of image structure and image content. Vision Res 2006; 46:2535-45. [PMID: 16545420 DOI: 10.1016/j.visres.2006.02.003] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2005] [Revised: 01/23/2006] [Accepted: 02/01/2006] [Indexed: 10/24/2022]
Abstract
Explorative eye movements specifically target some parts of a scene while ignoring others. Here, we investigate how local image structure--defined by spatial frequency contrast--and informative image content--defined by higher order image statistics-are weighted for the selection of fixation points. We measured eye movements of macaque monkeys freely viewing a set of natural and manipulated images outside a particular task. To probe the effect of scene content, we locally introduced patches of pink noise into natural images, and to probe the interaction with image structure, we altered the contrast of the noise. We found that fixations specifically targeted the natural image parts and spared the uninformative noise patches. However, both increasing and decreasing the contrast of the noise attracted more fixations, and, in the extreme cases, compensated the effect of missing content. Introducing patches from another natural image led to similar results. In all paradigms tested, the interaction between scene structure and informative scene content was the same in any of the first six fixations on an image, demonstrating that the weighting of these factors is constant during viewing of an image. These results question theories, which suggest that initial fixations are driven by stimulus structure whereas later fixations are determined by informative scene content.
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Affiliation(s)
- Christoph Kayser
- Max Planck Institute for Biological Cybernetics, Spemannstrasse 38, 72076 Tübingen, Germany.
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Einhäuser W, Kruse W, Hoffmann KP, König P. Differences of monkey and human overt attention under natural conditions. Vision Res 2005; 46:1194-209. [PMID: 16375943 DOI: 10.1016/j.visres.2005.08.032] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2005] [Revised: 05/11/2005] [Accepted: 08/17/2005] [Indexed: 11/25/2022]
Abstract
Rhesus monkeys are widely used as animal models of human attention. Such research rests upon the assumption that similar mechanisms underlie attention in both species. Here, we directly compare the influence of low-level stimulus features on overt attention in monkeys and humans under natural conditions. We recorded eye-movements in humans and rhesus monkeys during free-viewing of natural images. We find that intrinsic low-level features, such luminance-contrast, texture-contrast and saliency-as predicted by a standard model, are elevated at fixation points in the majority of images. These correlative effects are not significantly different between species. However, local image modifications affect both species differently: moderate modifications, which are in the range of natural fluctuations, attract overt attention in monkeys significantly stronger than they do in humans. In addition, humans show a higher inter-individual consistency regarding which locations they fixate than monkeys, in spite of the similarity for intrinsic low-level features. Taken together, these data demonstrate that-under natural conditions-low-level stimulus features affect attention in monkeys and humans differently.
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Affiliation(s)
- Wolfgang Einhäuser
- Institute of Neuroinformatics, University of Zurich and Swiss Federal Institute of Technology, ETH, Zurich, Switzerland.
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Droll JA, Hayhoe MM, Triesch J, Sullivan BT. Task Demands Control Acquisition and Storage of Visual Information. ACTA ACUST UNITED AC 2005; 31:1416-38. [PMID: 16366799 DOI: 10.1037/0096-1523.31.6.1416] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Attention and working memory limitations set strict limits on visual representations, yet researchers have little appreciation of how these limits constrain the acquisition of information in ongoing visually guided behavior. Subjects performed a brick sorting task in a virtual environment. A change was made to 1 of the features of the brick being held on about 10% of trials. Rates of change detection for feature changes were generally low and depended on the pick-up and put-down relevance of the feature to the sorting task. Subjects' sorting decision suggests that changes may be missed because of a failure to update the changed feature. The authors also explore how hand and eye behavior are coordinated for strategic acquisition and storage of visual information throughout the task.
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Affiliation(s)
- Jason A Droll
- Department of Brain and Cognitive Sciences, University of Rochester, Rochester, NY, USA.
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