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- Keyword
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- FMRI (5)
- Autism (4)
- Face recognition (4)
- Neuropsychology (4)
- Prosopagnosia (4)
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- Pure alexia (4)
- Adolescent (3)
- Hemispatial neglect (3)
- Parietal cortex (3)
- Path integration (3)
- Vision (3)
- Visual agnosia (3)
- Agnosia (2)
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- Brain Mapping (2)
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- Eye movements (2)
- Face perception (2)
- Face processing (2)
- Faces (2)
- Fusiform gyrus (2)
- Humans (2)
- Locomotion (2)
- Neglect (2)
- Object-based attention (2)
- Reading (2)
- Recognition (Psychology) (2)
- Spatial attention (2)
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Articles 1 - 30 of 77
Full-Text Articles in Social and Behavioral Sciences
Location, Location, Location: Alterations In The Functional Topography Of Face- But Not Object- Or Place-Related Cortex In Adolescents With Autism, K. Suzanne Scherf, Beatriz Luna, Nancy Minshew, Marlene Behrmann
Location, Location, Location: Alterations In The Functional Topography Of Face- But Not Object- Or Place-Related Cortex In Adolescents With Autism, K. Suzanne Scherf, Beatriz Luna, Nancy Minshew, Marlene Behrmann
Marlene Behrmann
In autism, impairments in face processing are a relatively recent discovery, but have quickly become a widely accepted aspect of the behavioral profile. Only a handful of studies have investigated potential atypicalities in autism in the development of the neural substrates mediating face processing. High-functioning individuals with autism (HFA) and matched typically developing (TD) controls watched dynamic movie vignettes of faces, common objects, buildings, and scenes of navigation while undergoing an fMRI scan. With these data, we mapped the functional topography of category-selective activation for faces bilaterally in the fusiform gyrus, occipital face area, and posterior superior temporal sulcus. Additionally, …
Perceptual Grouping Operates Independently Of Attentional Selection: Evidence From Hemispatial Neglect, Sarah Shomstein, Ruth Kimchi, Maxim Hammer, Marlene Behrmann
Perceptual Grouping Operates Independently Of Attentional Selection: Evidence From Hemispatial Neglect, Sarah Shomstein, Ruth Kimchi, Maxim Hammer, Marlene Behrmann
Marlene Behrmann
To what extent can human observers process visual information that is not currently the focus of attention? We evaluated the extent to which unattended visual information (i.e., that which appears on the neglected side of space in individuals with hemispatial neglect) is perceptually organized and influences the perceptual processing of information on the attended side. To examine this, patients (and matched controls) judged whether successive, complex checkerboard stimuli (targets), presented entirely to their intact side of space, were the same or different. Concurrent with this demanding task, irrelevant distractor elements appeared on the unattended side and either changed or retained …
Neuropsychological Approaches To Perceptual Organization, Marlene Behrmann
Neuropsychological Approaches To Perceptual Organization, Marlene Behrmann
Marlene Behrmann
This chapter takes a neuropsychological perspective on questions concerning analytic and holistic processing. It examines the behavior of seven brain-damaged patients who have problems with perceptual organization. These “integrative agnostic” patients seem to be disproportionately impaired on tasks tapping holistic configural processes compared to part-based processes. The first section of this chapter outlines three main empirical issues falling under the domain of perceptual organization: figure-ground organization, visual interpolation, and grouping. The second section contains a description of the patients. The third section examines the nature of the impairment in perceptual organization, in relation to figure-ground organization, visual interpolation, and grouping.
Missing The Big Picture: Impaired Development Of Global Shape Processing In Autism, K. Suzanne Scherf, Beatriz Luna, Ruth Kimchi, Nancy Minshew, Marlene Behrmann
Missing The Big Picture: Impaired Development Of Global Shape Processing In Autism, K. Suzanne Scherf, Beatriz Luna, Ruth Kimchi, Nancy Minshew, Marlene Behrmann
Marlene Behrmann
Individuals with autism exhibit hypersensitivity to local elements of the input, which may interfere with the ability to group visual elements perceptually. We investigated the development of perceptual grouping abilities in high-functioning individuals with autism (HFA) across a wide age range (8–30 years) using a classic compound letter global/local (GL) task and a more fine-grained microgenetic prime paradigm (MPP), including both few- and many-element hierarchical displays. In the GL task, contrary to the typically developing (TD) controls, HFA participants did not develop an increasing sensitivity to the global information with age. In the MPP, like the TD controls, individuals with …
Congenital Prosopagnosia: Face-Blind From Birth, Marlene Behrmann, Galia Avidan
Congenital Prosopagnosia: Face-Blind From Birth, Marlene Behrmann, Galia Avidan
Marlene Behrmann
Congenital prosopagnosia refers to the deficit in face processing that is apparent from early childhood in the absence of any underlying neurological basis and in the presence of intact sensory and intellectual function. Several such cases have been described recently and elucidating the mechanisms giving rise to this impairment should aid our understanding of the psychological and neural mechanisms mediating face processing. Fundamental questions include: What is the nature and extent of the face-processing deficit in congenital prosopagnosia? Is the deficit related to a more general perceptual deficit such as the failure to process configural information? Are any neural alterations …
Cued Visual Attention Does Not Distinguish Between Occluded And Occluding Objects, Craig Haimson, Marlene Behrmann
Cued Visual Attention Does Not Distinguish Between Occluded And Occluding Objects, Craig Haimson, Marlene Behrmann
Marlene Behrmann
Does visual attention spread from the cued end of an occluded object to locations occupied by inferred portions of that object? We investigated this question by using a probe detection paradigm with two-dimensional (2-D) displays of occluded objects. Probes could appear in occluded or nonoccluded locations on either a cued or noncued object. Participants responded faster to probes appearing within the region of space occupied by the cued object. This was true not only when the probe appeared in positions separated from the cued location by an occluder (as demonstrated by Moore, Yantis, & Vaughan, 1998), but also when it …
Distributed Circuits, Not Circumscribed Centers, Mediate Visual Recognition, Marlene Behrmann, David Plaut
Distributed Circuits, Not Circumscribed Centers, Mediate Visual Recognition, Marlene Behrmann, David Plaut
Marlene Behrmann
Increasingly, the neural mechanisms that support visual cognition are being conceptualized as a distributed but integrated system, as opposed to a set of individual, specialized regions that each subserve a particular visual behavior. Consequently, there is an emerging emphasis on characterizing the functional, structural, and computational properties of these broad networks. We present a novel theoretical perspective, which elucidates the developmental emergence, computational properties, and vulnerabilities of integrated circuits using face and word recognition as model domains. Additionally, we suggest that, rather than being disparate and independent, these neural circuits are overlapping and subject to the same computational constraints. Specifically, …
A Detailed Investigation Of Facial Expression Processing In Congenital Prosopagnosia As Compared To Acquired Prosopagnosia, Kate Humphreys, Galia Avidan, Marlene Behrmann
A Detailed Investigation Of Facial Expression Processing In Congenital Prosopagnosia As Compared To Acquired Prosopagnosia, Kate Humphreys, Galia Avidan, Marlene Behrmann
Marlene Behrmann
Whether the ability to recognize facial expression can be preserved in the absence of the recognition of facial identity remains controversial. The current study reports the results of a detailed investigation of facial expression recognition in three congenital prosopagnosic (CP) participants, in comparison with two patients with acquired prosopagnosia (AP) and a large group of 30 neurologically normal participants, including individually age- and gender-matched controls. Participants completed a fine-grained expression recognition paradigm requiring a six-alternative forced-choice response to continua of morphs of six different basic facial expressions (e.g. happiness and surprise). Accuracy, sensitivity and reaction times were measured. The performance …
Emergence Of Global Shape Processing Continues Through Adolescence, K. Suzanne Scherf, Marlene Behrmann, Ruth Kimchi, Beatriz Luna
Emergence Of Global Shape Processing Continues Through Adolescence, K. Suzanne Scherf, Marlene Behrmann, Ruth Kimchi, Beatriz Luna
Marlene Behrmann
The developmental trajectory of perceptual organization in humans is unclear. This study investigated perceptual grouping abilities across a wide age range (8–30 years) using a classic compound letter global/local (GL) task and a more fine-grained microgenetic prime paradigm (MPP) with both few- and many-element hierarchical displays. In the GL task, contrary to adults, both children and adolescents exhibited a classic local bias. In the MPP, all 3 age groups evinced a bias to individuate the few-element displays; however, the ability to encode the global shape of the many-element displays at the short prime durations increased with age. These results indicate …
Object-Based Attention: Strength Of Object Representation And Attentional Guidance, Sarah Shomstein, Marlene Behrmann
Object-Based Attention: Strength Of Object Representation And Attentional Guidance, Sarah Shomstein, Marlene Behrmann
Marlene Behrmann
Two or more features belonging to a single object are identified more quickly and more accurately than are features belonging to different objects—a finding attributed to sensory enhancement of all features belonging to an attended or selected object. However, several recent studies have suggested that this “single-object advantage” may be a product of probabilistic and configural strategic prioritizations rather than of object-based perceptual enhancement per se, challenging the underlying mechanism that is thought to give rise to object-based attention. In the present article, we further explore constraints on the mechanisms of object-based selection by examining the contribution of the strength …
The Functional Neuroanatomy Of Object Agnosia: A Case Study, Christina Konen, Marlene Behrmann, Mayu Nishimura, Sabine Kastner
The Functional Neuroanatomy Of Object Agnosia: A Case Study, Christina Konen, Marlene Behrmann, Mayu Nishimura, Sabine Kastner
Marlene Behrmann
Cortical reorganization of visual and object representations following neural injury was examined using fMRI and behavioral investigations. We probed the visual responsivity of the ventral visual cortex of an agnosic patient who was impaired at object recognition following a lesion to the right lateral fusiform gyrus. In both hemispheres, retinotopic mapping revealed typical topographic organization and visual activation of early visual cortex. However, visual responses, object-related, and -selective responses were reduced in regions immediately surrounding the lesion in the right hemisphere, and also, surprisingly, in corresponding locations in the structurally intact left hemisphere. In contrast, hV4 of the right hemisphere …
Updating Of Locations During Whole-Body Rotations In Patients With Hemispatial Neglect, John Philbeck, Marlene Behrmann, Jack Loomis
Updating Of Locations During Whole-Body Rotations In Patients With Hemispatial Neglect, John Philbeck, Marlene Behrmann, Jack Loomis
Marlene Behrmann
Posterior parietal cortex lesions have been associated with both hemispatial neglect and spatialupdating deficits. Currently, the relation between these processes remains poorly understood. We tested the ability of parietal patients with neglect to update remembered target locations during passive whole-body rotations. The rotations and manual pointing responses were executed with and without vision. During the rotation, the remembered location stayed on the same side of the body midline or crossed the midline. Parietal patients generally underestimated rotations, as compared with control groups, but updated targets equally well on either side of the body midline, regardless of the amount of updating …
Normal Movement Selectivity In Autism, Ilan Dinstein, Cibu Thomas, Kate Humphreys, Nancy Minshew, Marlene Behrmann, David Heeger
Normal Movement Selectivity In Autism, Ilan Dinstein, Cibu Thomas, Kate Humphreys, Nancy Minshew, Marlene Behrmann, David Heeger
Marlene Behrmann
It has been proposed that individuals with autism have difficulties understanding the goals and intentions of others because of a fundamental dysfunction in the mirror neuron system. Here, however, we show that individuals with autism exhibited not only normal fMRI responses in mirror system areas during observation and execution of hand movements but also exhibited typical movement-selective adaptation (repetition suppression) when observing or executing the same movement repeatedly. Movement selectivity is a defining characteristic of neurons involved in movement perception, including mirror neurons, and, as such, these findings argue against a mirror system dysfunction in autism.
Top-Down And Bottom-Up Attentional Guidance: Investigating The Role Of The Dorsal And Ventral Parietal Cortices, Sarah Shomstein, Jeongmi Lee, Marlene Behrmann
Top-Down And Bottom-Up Attentional Guidance: Investigating The Role Of The Dorsal And Ventral Parietal Cortices, Sarah Shomstein, Jeongmi Lee, Marlene Behrmann
Marlene Behrmann
Recent neuroimaging studies suggest that the superior parietal lobule (SPL) of the human cortex mediates goal-directed attentional orienting, while the temporo-parietal junction (TPJ) mediates stimulus-driven attentional orienting. Here, we investigated these brain-behavior correspondences by examining the performance of patients with an attentional deficit following a right hemisphere lesion. Patients completed two tasks, one sensitive to stimulus-driven attentional orienting and the other to goal-directed attentional orienting. Based on the behavioral profiles obtained on each task, patients were assigned to different groups and their lesion overlap explored. Patients who exhibited difficulties with goal-directed attentional orienting and showed concurrent “hyper-capture” presented with lesion …
What Is 'Left' When All Is Said And Done? Spatial Coding And Hemispatial Neglect, Marlene Behrmann, Joy Geng
What Is 'Left' When All Is Said And Done? Spatial Coding And Hemispatial Neglect, Marlene Behrmann, Joy Geng
Marlene Behrmann
Moving one's eyes to view a fly sitting on one's forearm requires that one know the spatial position of the fly. However, the process of spatial representation is fraught with problems.
Spatial Probability As An Attentional Cue In Visual Search, Joy Geng, Marlene Behrmann
Spatial Probability As An Attentional Cue In Visual Search, Joy Geng, Marlene Behrmann
Marlene Behrmann
We investigated the role of spatial probabilities in target location during participants’ performance of a visual search task. Experiments 1 and 2 demonstrated that spatial probabilities could serve as a powerful attentional bias that produced faster detection of targets in high-probability locations than of those in low- or random-probability locations. The effect could not be explained by repetition priming alone. Moreover, responses to targets in low-probability locations were slowed only when a distractor was present in the high-probability location. In Experiments 3–5, we compared the effects of spatial probability with an explicit endogenous cue and a salient exogenous cue. Facilitation …
Co-Analysis Of Brain Structure And Function Using Fmri And Diffusion-Weighted Imaging, Jeffrey Phillips, Adam Greenberg, John Pyles, Sudhir Pathak, Marlene Behrmann, Walter Schneider, Michael Tarr
Co-Analysis Of Brain Structure And Function Using Fmri And Diffusion-Weighted Imaging, Jeffrey Phillips, Adam Greenberg, John Pyles, Sudhir Pathak, Marlene Behrmann, Walter Schneider, Michael Tarr
Marlene Behrmann
The study of complex computational systems is facilitated by network maps, such as circuit diagrams. Such mapping is particularly informative when studying the brain, as the functional role that a brain area fulfills may be largely defined by its connections to other brain areas. In this report, we describe a novel, non-invasive approach for relating brain structure and function using magnetic resonance imaging (MRI). This approach, a combination of structural imaging of long-range fiber connections and functional imaging data, is illustrated in two distinct cognitive domains, visual attention and face perception. Structural imaging is performed with diffusion-weighted imaging (DWI) and …
Perceiving Parts And Shapes From Concave Surfaces, Anthony Cate, Marlene Behrmann
Perceiving Parts And Shapes From Concave Surfaces, Anthony Cate, Marlene Behrmann
Marlene Behrmann
“A hole is nothing at all, but it can break your neck.” In a similar fashion to the danger illustrated by this folk paradox, concave regions pose difficulties to theories of visual shape perception. We can readily identify their shapes, but according to principles of how observers determine part boundaries, concavities in a planar surface should have very different figural shapes from the ones that we perceive. In three experiments, we tested the hypothesis that observers perceive local image features differently in simulated 3-D concave and convex regions but use them to arrive at similar shape percepts. Stimuli were shape-from-shading …
Impaired Holistic Processing In Congenital Prosopagnosia, Galia Avidan, Michal Tanzer, Marlene Behrmann
Impaired Holistic Processing In Congenital Prosopagnosia, Galia Avidan, Michal Tanzer, Marlene Behrmann
Marlene Behrmann
It has long been argued that face processing requires disproportionate reliance on holistic or configural processing, relative to that required for non-face object recognition, and that a disruption of such holistic processing may be causally implicated in prosopagnosia. Previously, we demonstrated that individuals with congenital prosopagnosia (CP) did not show the normal face inversion effect (better performance for upright compared to inverted faces) and evinced a local (rather than the normal global) bias in a compound letter global/local (GL) task, supporting the claim of disrupted holistic processing in prosopagnosia. Here, we investigate further the nature of holistic processing impairments in …
Cortical Patterns Of Category-Selective Activation For Faces, Places And Objects In Adults With Autism, Kate Humphreys, Uri Hasson, Galia Avidan, Nancy Minshew, Marlene Behrmann
Cortical Patterns Of Category-Selective Activation For Faces, Places And Objects In Adults With Autism, Kate Humphreys, Uri Hasson, Galia Avidan, Nancy Minshew, Marlene Behrmann
Marlene Behrmann
Autism is associated with widespread atypicalities in perception, cognition and social behavior. A crucial question concerns how these atypicalities are reflected in the underlying brain activation. One way to examine possible perturbations of cortical organization in autism is to analyze the activation of category-selective ventral visual cortex, already clearly delineated in typical populations. We mapped out the neural correlates of face, place and common object processing, using functional magnetic resonance imaging (fMRI), in a group of high-functioning adults with autism and a typical comparison group, under both controlled and more naturalistic, viewing conditions. There were no consistent group differences in …
Attending To The Parts Of A Single Object: Part-Based Selection Limitations, Shaun Vecera, Marlene Behrmann, Joseph Filapek
Attending To The Parts Of A Single Object: Part-Based Selection Limitations, Shaun Vecera, Marlene Behrmann, Joseph Filapek
Marlene Behrmann
Studies of object-based attention have demonstrated poorer performance in dividing attention between two objects in a scene than in focusing attention on a single object. However, objects often are composed of several parts, and parts are central to theories of object recognition. Are parts also important for visual attention? That is, can attention be limited in the number of parts processed simultaneously? We addressed this question in four experiments. In Experiments 1 and 2, participants reported two attributes that appeared on the same part or on different parts of a single multipart object. Participants were more accurate in reporting the …
Face-Space Architectures: Evidence For The Use Of Independent Color-Based Features, Adrian Nestor, David Plaut, Marlene Behrmann
Face-Space Architectures: Evidence For The Use Of Independent Color-Based Features, Adrian Nestor, David Plaut, Marlene Behrmann
Marlene Behrmann
The concept of psychological face space lies at the core of many theories of face recognition and representation. To date, much of the understanding of face space has been based on principal component analysis (PCA); the structure of the psychological space is thought to reflect some important aspects of a physical face space characterized by PCA applications to face images. In the present experiments, we investigated alternative accounts of face space and found that independent component analysis provided the best fit to human judgments of face similarity and identification. Thus, our results challenge an influential approach to the study of …
Complementary Neural Representations For Faces And Words: A Computational Exploration, David Plaut, Marlene Behrmann
Complementary Neural Representations For Faces And Words: A Computational Exploration, David Plaut, Marlene Behrmann
Marlene Behrmann
A key issue that continues to generate controversy concerns the nature of the psychological, computational, and neural mechanisms that support the visual recognition of objects such as faces and words. While some researchers claim that visual recognition is accomplished by category-specific modules dedicated to processing distinct object classes, other researchers have argued for a more distributed system with only partially specialized cortical regions. Considerable evidence from both functional neuroimaging and neuropsychology would seem to favour the modular view, and yet close examination of those data reveals rather graded patterns of specialization that support a more distributed account. This paper explores …
Pure Alexia, Marie Montant, Marlene Behrmann
Pure Alexia, Marie Montant, Marlene Behrmann
Marlene Behrmann
Pure alexia is a reading disorder that occurs in literate individuals secondary to a lesion in the left occipito-temporal region.
Shared And Idiosyncratic Cortical Activation Patterns In Autism Revealed Under Continuous Real-Life Viewing Conditions, Uri Hasson, Galia Avidan, Hagar Gelbard, Ignacio Vallines, Michal Harel, Nancy Minshew, Marlene Behrmann
Shared And Idiosyncratic Cortical Activation Patterns In Autism Revealed Under Continuous Real-Life Viewing Conditions, Uri Hasson, Galia Avidan, Hagar Gelbard, Ignacio Vallines, Michal Harel, Nancy Minshew, Marlene Behrmann
Marlene Behrmann
Although widespread alterations in cortical structure have been documented in individuals with autism, the functional implications of these alterations remain to be determined. Here, we adopted a novel inter-subject correlation (inter-SC) and intra-subject correlation (intra-SC) technique to quantify the reliability of the spatio-temporal responses of functional MR activity in adults with autism during free-viewing of a popular audio–visual movie. Whereas these complex stimuli evoke highly reliable shared response time courses in typical individuals, cortical activity was more variable across individuals with autism (low inter-SC). Interestingly, when we measured the responses within an autistic individual across repeated presentations of the movie, …
Active Control Of Locomotion Facilitates Nonvisual Navigation, John W. Philbeck, Roberta L. Klatzky, Marlene Behrmann, Jack M. Loomis, Jeremy Goodridge
Active Control Of Locomotion Facilitates Nonvisual Navigation, John W. Philbeck, Roberta L. Klatzky, Marlene Behrmann, Jack M. Loomis, Jeremy Goodridge
Marlene Behrmann
In some navigation tasks, participants are more accurate if they view the environment beforehand. To characterize the benefits associated with visual previews, 32 blindfolded participants were guided along simple paths and asked to walk unassisted to a specified destination (e.g., the origin). Paths were completed without vision, with or without a visual preview of the environment. Previews did not necessarily improve nonvisual navigation. When previewed landmarks stood near the origin or at off-path locations, they provided little benefit; by contrast, when they specified intermediate destinations (thereby increasing the degree of active control), performance was greatly enhanced. The results suggest that …
Eccentricity Bias As An Organizing Principle For Human High-Order Object Areas, Uri Hasson, Ifat Levy, Marlene Behrmann, Talma Hendler, Rafael Malach
Eccentricity Bias As An Organizing Principle For Human High-Order Object Areas, Uri Hasson, Ifat Levy, Marlene Behrmann, Talma Hendler, Rafael Malach
Marlene Behrmann
We have recently proposed a center-periphery organization based on resolution needs, in which objects engaging in recognition processes requiring central-vision (e.g., face-related) are associated with center-biased representations, while objects requiring large-scale feature integration (e.g., buildings) are associated with periphery-biased representations. Here we tested this hypothesis by comparing the center-periphery organization with activations to five object categories: faces, buildings, tools, letter strings, and words. We found that faces, letter strings, and words were mapped preferentially within the center-biased representation. Faces showed a hemispheric lateralization opposite to that of letter strings and words. In contrast, buildings were mapped mainly to the periphery-biased …
Attentional Control: Temporal Relationships Within The Fronto-Parietal Network, Sarah Shomstein, Dwight Kravitz, Marlene Behrmann
Attentional Control: Temporal Relationships Within The Fronto-Parietal Network, Sarah Shomstein, Dwight Kravitz, Marlene Behrmann
Marlene Behrmann
Selective attention to particular aspects of incoming sensory information is enabled by a network of neural areas that includes frontal cortex, posterior parietal cortex, and, in the visual domain, visual sensory regions. Although progress has been made in understanding the relative contribution of these different regions to the process of visual attentional selection, primarily through studies using neuroimaging, rather little is known about the temporal relationships between these disparate regions. To examine this, participants viewed two rapid serial visual presentation (RSVP) streams of letters positioned to the left and right of fixation point. Before each run, attention was directed to …
Number Reading In Pure Alexia — A Review, Randi Starrfelt, Marlene Behrmann
Number Reading In Pure Alexia — A Review, Randi Starrfelt, Marlene Behrmann
Marlene Behrmann
It is commonly assumed that number reading can be intact in patients with pure alexia, and that this dissociation between letter/word recognition and number reading strongly constrains theories of visual word processing. A truly selective deficit in letter/word processing would strongly support the hypothesis that there is a specialized system or area dedicated to the processing of written words. To date, however, there has not been a systematic review of studies investigating number reading in pure alexia and so the status of this assumed dissociation is unclear. We review the literature on pure alexia from 1892 to 2010, and find …
Probability Cuing Of Target Location Facilitates Visual Search Implicitly In Normal Participants And Patients With Hemispatial Neglect, Joy Geng, Marlene Behrmann
Probability Cuing Of Target Location Facilitates Visual Search Implicitly In Normal Participants And Patients With Hemispatial Neglect, Joy Geng, Marlene Behrmann
Marlene Behrmann
We explored how variability in the probability of target locations affects visual search in normal individuals and in patients with hemispatial neglect, a deficit in attending to the contralesional side of space. Young and elderly normal participants responded faster when targets appeared in the more probable region than when targets appeared in the less probable region. Similarly, patients were sensitive to the distribution of targets, even in the neglected field. Although the attentional gradient that characterizes neglect was not eliminated, the response facilitation due to the probability distribution was proportionate to that of control participants and equal in magnitude across …