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63
Representation, space and Hollywood Squares: Looking at things that aren’t there anymore
- Cognition
, 2000
"... things that aren't there anymore ..."
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Neural correlates of conceptual knowledge for actions
- Cognitive Neuropsychology
, 2003
"... The neural correlates of conceptual knowledge for actions are not well understood. To begin to address this knowledge gap, we tested the hypothesis that the retrieval of conceptual knowledge for actions depends on neural systems located in higher-order association cortices of left premotor/prefronta ..."
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Cited by 48 (3 self)
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The neural correlates of conceptual knowledge for actions are not well understood. To begin to address this knowledge gap, we tested the hypothesis that the retrieval of conceptual knowledge for actions depends on neural systems located in higher-order association cortices of left premotor/prefrontal, parietal, and posterior middle temporal regions. The investigation used the lesion method and involved 90 subjects with damage to various regions of the left or right hemisphere. The experimental tasks measured retrieval of knowledge for actions, in a nonverbal format: Subjects evaluated attributes of pictured actions, and compared and matched pictures of actions. In support of our hypothesis, we found that the regions of highest lesion overlap in subjects with impaired retrieval of conceptual knowledge for actions were in the left premotor/prefrontal sector, the left parietal region, and in the white matter underneath the left posterior middle temporal region. These sites are partially distinct from those iden-tified previously as being important for the retrieval of words for actions. We propose that a key function of the sites is to operate as two-way intermediaries between perception and concept retrieval, to pro-mote the retrieval of the multidimensional aspects of knowledge that are necessary and sufficient for the mental representation of a concept of a given action.
Three-dimensional object recognition based on the combination of views
- Cognition
, 1998
"... Visual object recognition is complicated by the fact that the same 3D object can give rise to a large variety of projected images that depend on the viewing conditions, such as viewing direction, distance, and illumination. This paper describes a computational approach that uses combinations of a sm ..."
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Cited by 47 (0 self)
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Visual object recognition is complicated by the fact that the same 3D object can give rise to a large variety of projected images that depend on the viewing conditions, such as viewing direction, distance, and illumination. This paper describes a computational approach that uses combinations of a small number of object views to deal with the effects of viewing direction. The first part of the paper is an overview of the approach based on previous work. It is then shown that, in agreement with psychophysical evidence, the view-combinations approach can use views of different class members rather than multiple views of a single object, to obtain class-based generalization. A number of extensions to the basic scheme are considered, including the use of non-linear combinations, using 3D versus 2D information, and the role of coarse classification on the way to precise identification. Finally, psychophysical and biological aspects of the view-combination approach are discussed. Compared with approaches that treat object recognition as a symbolic high-level activity, in the view-combination approach the emphasis is on processes that are simpler and pictorial in nature. © 1998 Elsevier Science B.V. All rights reserved Keywords: Three-dimensional object recognition; View combinations; Classification 1. Recognition and the variability of object views For biological visual systems, visual object recognition is a spontaneous, natural activity. In contrast, the recognition of common objects is still beyond the capabilities of current computer vision systems. In this paper I will examine certain aspects of the recognition problem and outline an approach to recognition based on the
Two is not always better than one: A critical evaluation of twosystem theories
- Perspectives on Psychological Science
, 2009
"... ABSTRACT—Over the past two decades, there has been an upsurge in theoretical frameworks alluding to the exis-tence of two different processing systems that supposedly operate according to different rules. This article critically examines the scientific advance offered by these theories (in particula ..."
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Cited by 40 (3 self)
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ABSTRACT—Over the past two decades, there has been an upsurge in theoretical frameworks alluding to the exis-tence of two different processing systems that supposedly operate according to different rules. This article critically examines the scientific advance offered by these theories (in particular advances in the domains of reasoning, decision making, and social cognition) and questions their theoretical coherence as well as the evidence for their existence. We scrutinize the conceptual underpinnings of two-system models and explicate the assumptions underlying these models to see whether they are reason-able. We also evaluate the empirical paradigms used to validate two-system models and ponder about their explanatory strength and predictive power. Given the popularity of these models, we discuss the appeal of
From Knowing What to Knowing Where: Modeling Object-Based Attention with Feedback Disinhibition of Activiation
, 2001
"... We propose a neural model of visual object-based attention in which the identity of an object is used to select its location in an array of objects. The model is based on neural activity observed in visual search tasks performed by monkeys. In the model, the identity of the object (target) is select ..."
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Cited by 34 (9 self)
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We propose a neural model of visual object-based attention in which the identity of an object is used to select its location in an array of objects. The model is based on neural activity observed in visual search tasks performed by monkeys. In the model, the identity of the object (target) is selected in the higher areas of the ventral stream by means of a cue. Feedback activation from these higher areas carries information about the identity of the target to the (lower) retinotopic areas of the ventral stream. In these areas, the feedback activation interacts with feedforward activation produced by the object array. The interaction occurs in local microcircuits, and results in a selective activation on locations in the retinotopic areas of the visual stream that correspond to the location of the target in the object array. The selective activation consists of a form of gain control, produced by disinhibition. Transmitted to the dorsal stream, this activation directs spatial attention to the location of the target. In this way, an action directed at the target can be generated.
Foveated Shot Detection for Video Segmentation
- IEEE Transactions on Circuits and Systems for Video Technology
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Does selecting one visual object from several require inhibition of the actions associated with nonselected objects
- Journal of Experimental Psychology: Human Perception and Performance
, 2007
"... Four experiments are described in which 1 visual object (the target) was selected from another (the distractor) according to its color (Experiments 1, 2, and 4) or its relative location (Experiment 3) and then was classified according to a simple geometric property. Object classification was signale ..."
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Cited by 21 (1 self)
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Four experiments are described in which 1 visual object (the target) was selected from another (the distractor) according to its color (Experiments 1, 2, and 4) or its relative location (Experiment 3) and then was classified according to a simple geometric property. Object classification was signaled as fast as possible by a precision or power grip response, and this grip was either compatible or incompatible with either object. When targets were selected by color, target-compatible grip responses were facilitated, but distractor-compatible grip responses were impaired. When targets were selected by location, similar results were obtained for target-compatible grip responses, but not distractor-compatible grip responses. These data are explained in terms of the involvement of action codes in object-level selection.
Action comprehension: Deriving spatial and functional relations
- J. Exp. Psych. Human Perception and Performance
"... A perceived action can be understood only when information about the action carried out and the objects used are taken into account. It was investigated how spatial and functional information contributes to establishing these relations. Participants observed static frames showing a hand wielding an ..."
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Cited by 12 (0 self)
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A perceived action can be understood only when information about the action carried out and the objects used are taken into account. It was investigated how spatial and functional information contributes to establishing these relations. Participants observed static frames showing a hand wielding an instrument and a potential target object of the action. The 2 elements could either match or mismatch, spatially or functionally. Participants were required to judge only 1 of the 2 relations while ignoring the other. Both irrelevant spatial and functional mismatches affected judgments of the relevant relation. Moreover, the functional relation provided a context for the judgment of the spatial relation but not vice versa. The results are discussed in respect to recent accounts of action understanding.
Impaired Perceptual Memory of Locations across Gaze-shifts in Patients with Unilateral Spatial Neglect
"... & Right hemisphere lesions often lead to severe disorders in spatial awareness and behavior, such as left hemispatial neglect. Neglect involves not only pathological biases in attention and exploration but also deficits in internal representations of space and spatial working memory. Here we des ..."
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Cited by 9 (0 self)
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& Right hemisphere lesions often lead to severe disorders in spatial awareness and behavior, such as left hemispatial neglect. Neglect involves not only pathological biases in attention and exploration but also deficits in internal representations of space and spatial working memory. Here we designed a new paradigm to test whether one potential component may involve a failure to maintain an updated representation of visual locations across delays when a gaze-shift intervenes. Right hemisphere patients with varying severity of left spatial neglect had to encode a single target location and retain it across an interval of 2 or 3 sec, during which the target was transiently removed, before a subsequent probe appeared for a same/ different location judgment. During the delay, gaze could have to shift to either side of the remembered location, or no gazeshift
Gaze-eccentricity effects on road position and steering
- Journal of Experimental Psychology: Applied
, 2002
"... The effects of gaze eccentricity on the steering of an automobile were studied. Drivers performed an attention task while attempting to drive down the middle of a straight road in a simulation. Steering was biased in the direction of fixation, and deviation from the center of the road was proportion ..."
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Cited by 9 (0 self)
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The effects of gaze eccentricity on the steering of an automobile were studied. Drivers performed an attention task while attempting to drive down the middle of a straight road in a simulation. Steering was biased in the direction of fixation, and deviation from the center of the road was proportional to the gaze direction until saturation at approximately 15 ° gaze-angle from straight ahead. This effect remains when the position of the head was controlled and a reverse-steering task was used. Furthermore, the effect was not dependent on speed but reversed when the forward movement of the driver was removed from the simulation. Thus, small deviations in a driver’s gaze can lead to significant impairments of the ability to drive a straight course. Human beings who are active in the environment need to know where they are headed, accurately judge their progress toward a goal, and adapt to unexpected changes in the environment to reach that goal. When one considers tasks of applied navigation such as driving, however, one may be struck by the remarkable automa-ticity with which such behaviors are performed. Because of the confidence many people have in their ability to navigate effec-
