When You Do Not Get the Whole Picture: Scene Perception After Occipital Cortex Lesions

Background: Occipital cortex lesions (OCLs) typically result in visual field defects (VFDs) contralateral to the damage. VFDs are usually mapped with perimetry involving the detection of point targets. This, however, ignores the important role of integration of visual information across locations in many tasks of everyday life. Here, we ask whether standard perimetry can fully characterize the consequences of OCLs. We compare performance on a rapid scene discrimination task of OCL participants and healthy observers with simulated VFDs. While the healthy observers will only suffer the loss of part of the visual scene, the damage in the OCL participants may further compromise global visual processing.Methods: VFDs were mapped with Humphrey perimetry, and participants performed two rapid scene discrimination tasks. In healthy participants, the VFDs were simulated with hemi- and quadrant occlusions. Additionally, the GIST model, a computational model of scene recognition, was used to make individual predictions based on the VFDs.Results: The GIST model was able to predict the performance of controls regarding the effects of the local occlusion. Using the individual predictions of the GIST model, we can determine that the variability between the OCL participants is much larger than the extent of the VFD could account for. The OCL participants can further be categorized as performing worse, the same, or better as their VFD would predict.Conclusions: While in healthy observers the extent of the simulated occlusion accounts for their performance loss, the OCL participants’ performance is not fully determined by the extent or shape of their VFD as measured with Humphrey perimetry. While some OCL participants are indeed only limited by the local occlusion of the scene, for others, the lesions compromised the visual network in a more global and disruptive way. Yet one outperformed a healthy observer, suggesting a possible adaptation to the VFD. Preliminary analysis of neuroimaging data suggests that damage to the lateral geniculate nucleus and corpus callosum might be associated with the larger disruption of rapid scene discrimination. We believe our approach offers a useful behavioral tool for investigating why similar VFDs can produce widely differing limitations in everyday life.

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Refixation Patterns of Mind-wandering during Real-world Scene Perception

10.31234/osf.io/ezaxc ◽

2020 ◽

Author(s):

Han Zhang ◽

Nicola C Anderson ◽

Kevin Miller

Keyword(s):

Eye Movements ◽

Cognitive Processing ◽

Real World ◽

Visual Processing ◽

Visual Information ◽

Scene Perception ◽

Mind Wandering ◽

Quantification Analysis ◽

The Difference ◽

Thought Probes

Recent studies have shown that mind-wandering (MW) is associated with changes in eye movement parameters, but have not explored how MW affects the sequential pattern of eye movements involved in making sense of complex visual information. Eye movements naturally unfold over time and this process may reveal novel information about cognitive processing during MW. The current study used Recurrence Quantification Analysis (Anderson, Bischof, Laidlaw, Risko, & Kingstone, 2013) to describe the pattern of refixations (fixations directed to previously-inspected regions) during MW. Participants completed a real-world scene encoding task and responded to thought probes assessing intentional and unintentional MW. Both types of MW were associated with worse memory of the scenes. Importantly, RQA showed that scanpaths during unintentional MW were more repetitive than during on-task episodes, as indicated by a higher recurrence rate and more stereotypical fixation sequences. This increased repetitiveness suggests an adaptive response to processing failures through re-examining previous locations. Moreover, this increased repetitiveness contributed to fixations focusing on a smaller spatial scale of the stimuli. Finally, we were also able to validate several traditional measures: both intentional and unintentional MW were associated with fewer and longer fixations; Eye-blinking increased numerically during both types of MW but the difference was only significant for unintentional MW. Overall, the results advanced our understanding of how visual processing is affected during MW by highlighting the sequential aspect of eye movements.

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Contrasting Cortical Activity Associated with Category Memory and Recognition Memory

Learning & Memory ◽

10.1101/lm.5.6.420 ◽

1998 ◽

Vol 5 (6) ◽

pp. 420-428 ◽

Cited By ~ 2

Author(s):

Paul J. Reber ◽

Craig E.L. Stark ◽

Larry R. Squire

Keyword(s):

Recognition Memory ◽

Visual Processing ◽

Functional Neuroimaging ◽

Brain Activity ◽

Recognition Task ◽

Occipital Cortex ◽

Fmri Data ◽

Categorization Task ◽

Neuroimaging Data ◽

Familiar Stimuli

We collected functional neuroimaging data while volunteers performed similar categorization and recognition memory tasks. In the categorization task, volunteers first studied a series of 40 dot patterns that were distortions of a nonstudied prototype dot pattern. After a delay, while fMRI data were collected, they categorized 72 novel dot patterns according to whether or not they belonged to the previously studied category. In the recognition task, volunteers first studied five dot patterns eight times each. After a delay, while fMRI data were collected, they judged whether each of 72 dot patterns had been studied earlier. We found strikingly different patterns of brain activity in visual processing areas for the two tasks. During the categorization task, the familiar stimuli were associated with decreased activity in posterior occipital cortex, whereas during the recognition task, the familiar stimuli were associated with increased activity in this area. The findings indicate that these two types of memory have contrasting effects on early visual processing and reinforce the view that declarative and nondeclarative memory operate independently.

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Transcranial Magnetic Stimulation to the Transverse Occipital Sulcus Affects Scene but Not Object Processing

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00372 ◽

2013 ◽

Vol 25 (6) ◽

pp. 961-968 ◽

Cited By ~ 32

Author(s):

Rachel E. Ganaden ◽

Caitlin R. Mullin ◽

Jennifer K. E. Steeves

Keyword(s):

Scene Perception ◽

Occipital Cortex ◽

Control Site ◽

Image Features ◽

Retrosplenial Cortex ◽

Scene Recognition ◽

Scene Categorization ◽

Object Processing ◽

Inhibitory Mechanisms ◽

Scene Processing

Traditionally, it has been theorized that the human visual system identifies and classifies scenes in an object-centered approach, such that scene recognition can only occur once key objects within a scene are identified. Recent research points toward an alternative approach, suggesting that the global image features of a scene are sufficient for the recognition and categorization of a scene. We have previously shown that disrupting object processing with repetitive TMS to object-selective cortex enhances scene processing possibly through a release of inhibitory mechanisms between object and scene pathways [Mullin, C. R., & Steeves, J. K. E. TMS to the lateral occipital cortex disrupts object processing but facilitates scene processing. Journal of Cognitive Neuroscience, 23, 4174–4184, 2011]. Here we show the effects of TMS to the transverse occipital sulcus (TOS), an area implicated in scene perception, on scene and object processing. TMS was delivered to the TOS or the vertex (control site) while participants performed an object and scene natural/nonnatural categorization task. Transiently interrupting the TOS resulted in significantly lower accuracies for scene categorization compared with control conditions. This demonstrates a causal role of the TOS in scene processing and indicates its importance, in addition to the parahippocampal place area and retrosplenial cortex, in the scene processing network. Unlike TMS to object-selective cortex, which facilitates scene categorization, disrupting scene processing through stimulation of the TOS did not affect object categorization. Further analysis revealed a higher proportion of errors for nonnatural scenes that led us to speculate that the TOS may be involved in processing the higher spatial frequency content of a scene. This supports a nonhierarchical model of scene recognition.

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Alpha fluctuations regulate the accrual of visual information to awareness

10.1101/2020.09.16.298166 ◽

2020 ◽

Author(s):

Mireia Torralba ◽

Alice Drew ◽

Alba Sabaté San José ◽

Luis Morís Fernández ◽

Salvador Soto-Faraco

Keyword(s):

Binocular Rivalry ◽

Visual Information ◽

Brain Activity ◽

Visual Awareness ◽

Sensory Information ◽

Occipital Cortex ◽

Visual Inputs ◽

Perceptual Alternation ◽

Eeg Recordings ◽

The Individual

AbstractEndogenous brain processes play a paramount role in shaping up perceptual phenomenology, as illustrated by the alternations experienced by humans (and other animals) when watching perceptually ambiguous, static images. Here, we hypothesised that endogenous alpha fluctuations in the visual cortex pace the accumulation of sensory information leading to perceptual outcomes. We addressed this hypothesis using binocular rivalry combined with visual entrainment and electroencephalography in humans (42 female, 40 male). The results revealed a correlation between the individual frequency of alpha oscillations in the occipital cortex and perceptual alternation rates experienced during binocular rivalry. In subsequent experiments we show that regulating endogenous brain activity via entrainment produced corresponding changes in perceptual alternation rate, which were observed only in the alpha range but not at lower entrainment frequencies. Overall, rhythmic alpha stimulation resulted in faster perceptual alternation rates, compared to arrhythmic or no stimulation. These findings support the notion that visual information is accumulated via alpha cycles to promote the emergence of conscious perceptual representations. We suggest that models of binocular rivalry incorporating posterior alpha as a pacemaker can provide an important advance in the comprehension of the dynamics of visual awareness.Significance statementMainstream theories in cognitive neuroscience agree that endogenous brain processes play a paramount role in shaping our perceptual experience of sensory inputs. In vision, endogenous fluctuations in the alpha rhythm have been pointed out to regulate visual inputs to perception. In support of this hypothesis, here we used EEG recordings and visual entrainment to demonstrate that inter-individual differences in the speed of endogenous alpha fluctuations in the brain are causally related to the accrual of visual information to awareness. These findings provide, for the first time, evidence for alpha-gated regulation of the dynamics of alternations in conscious visual perception.

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SELF-PRESERVATION OF THE PHYSICAL HEALTH OF STUDENTS IN THE VIEW OF THEIR PROFESSIONAL AND LABOR COMPETENCIES

Global problems of modernity ◽

10.26787/nydha-2713-2048-2020-1-10-11-12-31-40 ◽

2020 ◽

pp. 31-40

Author(s):

Pavlov B.S. ◽

Sentyurina L.B. ◽

Pronina E.I. ◽

Pavlov D.B. ◽

Saraikin D.A.

Keyword(s):

Physical Health ◽

Everyday Life ◽

Healthy Lifestyle ◽

Leisure Activities ◽

Physical Culture ◽

Federal Districts ◽

The Individual ◽

Effective Use ◽

Academy Of Sciences ◽

Labor Potential

The state policy of health preservation of Russians and the process of introducing a healthy lifestyle into their everyday life is hampered by the lack of sufficient self-activity and purposefulness of the individual ecological and valeological behavior of representatives of various population groups. According to the authors of the article, one of the important indicators of the maturity of professional and labor competencies of school and student youth is their readiness and desire for permanent self-preserving behavior. “With numbers in hand,” the authors show the scale of deviant deviations and the phenomena of spontaneous irresponsibility in the educational and leisure activities of students, hindering the preservation and development of physical culture, the accumulation and effective use of their psychophysiological and labor potential. The conclusions of the proposal of the authors of the article are based on the results of a number of sociological surveys conducted in 2000-2020. at the Institute of Economics of the Ural Branch of the Russian Academy of Sciences in a number of secondary schools and universities of the Ural and Volga Federal Districts.

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Effects of Symbol Structure on Visual Information Processing

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193128302700503 ◽

1983 ◽

Vol 27 (5) ◽

pp. 354-354

Author(s):

Bruce W. Hamill ◽

Robert A. Virzi

Keyword(s):

Information Processing ◽

Visual Processing ◽

Visual Information ◽

Context Effects ◽

Response Times ◽

Search Time ◽

Visual Information Processing ◽

Array Size ◽

Serial Search ◽

Feature Structure

This investigation addresses the problem of attention in the processing of symbolic information from visual displays. Its scope includes the nature of attentive processes, the structural properties of stimuli that influence visual information processing mechanisms, and the manner in which these factors interact in perception. Our purpose is to determine the effects of configural feature structure on visual information processing. It is known that for stimuli comprising separable features, one can distinguish between conditions in which only one relevant feature differs among stimuli in the array being searched and conditions in which conjunctions of two (or more) features differ: Since the visual process of conjoining separable features is additive, this fact is reflected in search time as a function of array size, with feature conditions yielding flat curves associated with parallel search (no increase in search time across array sizes) and conjunction conditions yielding linearly increasing curves associated with serial search. We studied configural-feature stimuli within this framework to determine the nature of visual processing for such stimuli as a function of their feature structure. Response times of subjects searching for particular targets among structured arrays of distractors were measured in a speeded visual search task. Two different sets of stimulus materials were studied in array sizes of up to 32 stimuli, using both tachistoscope and microcomputer-based CRT presentation for each. Our results with configural stimuli indicate serial search in all of the conditions, with the slope of the response-time-by-array-size function being steeper for conjunction conditions than for feature conditions. However, for each of the two sets of stimuli we studied, there was one configuration that stood apart from the others in its set in that it yielded significantly faster response times, and in that conjunction conditions involving these particular stimuli tended to cluster with the feature conditions rather than with the other conjunction conditions. In addition to these major effects of particular targets, context effects also appeared in our results as effects of the various distractor sets used; certain of these context effects appear to be reversible. The effects of distractor sets on target search were studied in considerable detail. We have found interesting differences in visual processing between stimuli comprising separable features and those comprising configural features. We have also been able to characterize the effects we have found with configural-feature stimuli as being related to the specific feature structure of the target stimulus in the context of the specific feature structure of distractor stimuli. These findings have strong implications for the design of symbology that can enhance visual performance in the use of automated displays.

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The Neurophysiology of Backward Visual Masking: Information Analysis

Journal of Cognitive Neuroscience ◽

10.1162/089892999563409 ◽

1999 ◽

Vol 11 (3) ◽

pp. 300-311 ◽

Cited By ~ 127

Author(s):

Edmund T. Rolls ◽

Martin J. Tovée ◽

Stefano Panzeri

Keyword(s):

Visual Processing ◽

Visual Information ◽

Computational Models ◽

Direct Evidence ◽

Visual Masking ◽

Neuronal Response ◽

Short Soas ◽

Stimulus Onset ◽

Backward Masking ◽

Neuronal Responses

Backward masking can potentially provide evidence of the time needed for visual processing, a fundamental constraint that must be incorporated into computational models of vision. Although backward masking has been extensively used psychophysically, there is little direct evidence for the effects of visual masking on neuronal responses. To investigate the effects of a backward masking paradigm on the responses of neurons in the temporal visual cortex, we have shown that the response of the neurons is interrupted by the mask. Under conditions when humans can just identify the stimulus, with stimulus onset asynchronies (SOA) of 20 msec, neurons in macaques respond to their best stimulus for approximately 30 msec. We now quantify the information that is available from the responses of single neurons under backward masking conditions when two to six faces were shown. We show that the information available is greatly decreased as the mask is brought closer to the stimulus. The decrease is more marked than the decrease in firing rate because it is the selective part of the firing that is especially attenuated by the mask, not the spontaneous firing, and also because the neuronal response is more variable at short SOAs. However, even at the shortest SOA of 20 msec, the information available is on average 0.1 bits. This compares to 0.3 bits with only the 16-msec target stimulus shown and a typical value for such neurons of 0.4 to 0.5 bits with a 500-msec stimulus. The results thus show that considerable information is available from neuronal responses even under backward masking conditions that allow the neurons to have their main response in 30 msec. This provides evidence for how rapid the processing of visual information is in a cortical area and provides a fundamental constraint for understanding how cortical information processing operates.

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The Rapid Extraction of Gist—Early Neural Correlates of High-level Visual Processing

Journal of Cognitive Neuroscience ◽

10.1162/jocn_a_00100 ◽

2012 ◽

Vol 24 (2) ◽

pp. 521-529 ◽

Cited By ~ 13

Author(s):

Frank Oppermann ◽

Uwe Hassler ◽

Jörg D. Jescheniak ◽

Thomas Gruber

Keyword(s):

Visual Processing ◽

Time Course ◽

Occipital Cortex ◽

Stimulus Onset ◽

Gamma Band ◽

Oscillatory Activity ◽

Rapid Extraction ◽

The Right ◽

High Level ◽

Individual Objects

The human cognitive system is highly efficient in extracting information from our visual environment. This efficiency is based on acquired knowledge that guides our attention toward relevant events and promotes the recognition of individual objects as they appear in visual scenes. The experience-based representation of such knowledge contains not only information about the individual objects but also about relations between them, such as the typical context in which individual objects co-occur. The present EEG study aimed at exploring the availability of such relational knowledge in the time course of visual scene processing, using oscillatory evoked gamma-band responses as a neural correlate for a currently activated cortical stimulus representation. Participants decided whether two simultaneously presented objects were conceptually coherent (e.g., mouse–cheese) or not (e.g., crown–mushroom). We obtained increased evoked gamma-band responses for coherent scenes compared with incoherent scenes beginning as early as 70 msec after stimulus onset within a distributed cortical network, including the right temporal, the right frontal, and the bilateral occipital cortex. This finding provides empirical evidence for the functional importance of evoked oscillatory activity in high-level vision beyond the visual cortex and, thus, gives new insights into the functional relevance of neuronal interactions. It also indicates the very early availability of experience-based knowledge that might be regarded as a fundamental mechanism for the rapid extraction of the gist of a scene.

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CNTM-03. Functional connectivity networks in patients with brain tumors and vascular lesions in the occipital cortex

Neuro-Oncology ◽

10.1093/neuonc/noab196.901 ◽

2021 ◽

Vol 23 (Supplement_6) ◽

pp. vi224-vi225

Author(s):

Katharina Rosengarth ◽

Katharina Hense ◽

Tina Plank ◽

Mark Greenlee ◽

Christina Wendl ◽

...

Keyword(s):

Functional Connectivity ◽

Brain Tumors ◽

Visual Processing ◽

Network Connectivity ◽

Occipital Cortex ◽

Brain Lesions ◽

Vascular Lesions ◽

Surrounding Tissue ◽

Tumor Patients ◽

Default Mode

Abstract OBJECTIVE Space-occupying brain lesions as brain tumors in the occipital lobe have only been sparsely investigated so far, as this localization is extremely rare with only 1% of cases. It is still unclear how this affects the overall organization of the visual system. We investigated functional connectivity of functional networks associated with higher visual processing between patients with occipital space-occupying lesion in the occipital cortex and healthy controls. METHODS 12 patients with brain tumors, 7 patients with vascular lesions in the occipital cortex and 19 healthy subjects matched for age and sex were included. During functional MRI patients and subjects performed a visual excentricity mapping task. Data analysis was done using CONN toolbox based on Matlab. See-to-ROI connectivities of 23 Regions of Interest (ROIs) implemented in the CONN toolbox which were assigned to the Default Mode, Visual, Salience, Dorsal Attention, and Frontoparietal network were assessed. For each subject, connectivity was calculated using Fischer transformed pairwise correlations. These correlations were first considered separately for each group in one-sample analyses and then compared between the groups. RESULTS Main results show, that compared to control subjects and vascular patients, tumor patients showed weaker intra-network connectivity of components of all networks except the default-network. Tumor patients showed even stronger between-network connectivity in the default-mode network compared to the other groups. Weaker connectivity was observed within the salience network in both patient groups compared to controls. CONCLUSION The results indicate that in the course of the disease, compensatory countermeasures take place in the brain against a brain tumor or a space-occupying brain lesion with the aim of maintaining the performance level and cognitive processes for as long as possible. However, more research is needed in this area to understand the mechanisms and effects of brain tumors and space-consuming brain lesions on surrounding tissue.

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An Integrated Approach for Traffic Scene Understanding from Monocular Cameras

10.51202/9783186815125 ◽

2021 ◽

Author(s):

Malte Oeljeklaus

Keyword(s):

Neural Network ◽

Convolutional Neural Network ◽

Scene Perception ◽

Integrated Approach ◽

Image Features ◽

Road Users ◽

Environment Model ◽

Computational Performance ◽

Spatial Reconstruction ◽

The Individual

This thesis investigates methods for traffic scene perception with monocular cameras for a basic environment model in the context of automated vehicles. The developed approach is designed with special attention to the computational limitations present in practical systems. For this purpose, three different scene representations are investigated. These consist of the prevalent road topology as the global scene context, the drivable road area and the detection and spatial reconstruction of other road users. An approach is developed that allows for the simultaneous perception of all environment representations based on a multi-task convolutional neural network. The obtained results demonstrate the efficiency of the multi-task approach. In particular, the effects of shareable image features for the perception of the individual scene representations were found to improve the computational performance. Contents Nomenclature VII 1 Introduction 1 1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 1.2 Outline and contributions . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 2 Related Work and Fundamental Background 8 2.1 Advances in CNN...

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