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Current Biology : CB Oct 2011Attention is crucial for visual perception because it allows the visual system to effectively use its limited resources by selecting behaviorally and cognitively...
Attention is crucial for visual perception because it allows the visual system to effectively use its limited resources by selecting behaviorally and cognitively relevant stimuli from the large amount of information impinging on the eyes. Reflexive, stimulus-driven attention is essential for successful interactions with the environment because it can, for example, speed up responses to life-threatening events. It is commonly believed that exogenous attention operates in the retinotopic coordinates of the early visual system. Here, using a novel experimental paradigm [1], we show that a nonretinotopic cue improves both accuracy and reaction times in a visual search task. Furthermore, the influence of the cue is limited both in space and time, a characteristic typical of exogenous cueing. These and other recent findings show that many more aspects of vision are processed nonretinotopically than previously thought.
Topics: Attention; Cues; Humans; Pattern Recognition, Visual; Space Perception; Visual Perception
PubMed: 22000104
DOI: 10.1016/j.cub.2011.08.059 -
The Journal of Physiology Nov 2016
Topics: Animals; Grid Cells; Humans; Models, Neurological; Movement; Neurons; Space Perception
PubMed: 27870122
DOI: 10.1113/JP273087 -
Scientific Reports Jan 2023Several spaces around the body have been described, contributing to interactions with objects (peripersonal) or people (interpersonal and personal). The sensorimotor and...
Several spaces around the body have been described, contributing to interactions with objects (peripersonal) or people (interpersonal and personal). The sensorimotor and multisensory properties of action peripersonal space are assumed to be involved in the regulation of social personal and interpersonal spaces, but experimental evidence is tenuous. Hence, the present study investigated the relationship between multisensory integration and action and social spaces. Participants indicated when an approaching social or non-social stimulus was reachable by hand (reachable space), at a comfortable distance to interact with (interpersonal space), or at a distance beginning to cause discomfort (personal space). They also responded to a tactile stimulation delivered on the trunk during the approach of the visual stimulus (multisensory integration space). Results showed that participants were most comfortable with stimuli outside reachable space, and felt uncomfortable with stimuli well inside it. Furthermore, reachable, personal and interpersonal spaces were all positively correlated. Multisensory integration space extended beyond all other spaces and correlated only with personal space when facing a social stimulus. Considered together, these data confirm that action peripersonal space contributes to the regulation of social spaces and that multisensory integration is not specifically constrained by the spaces underlying motor action and social interactions.
Topics: Humans; Touch; Personal Space; Touch Perception; Emotions; Hand; Space Perception
PubMed: 36604525
DOI: 10.1038/s41598-023-27514-6 -
Journal of Vision May 2019Spatial summation of luminance contrast signals has historically been psychophysically measured with stimuli isolated in spatial frequency (i.e., narrowband). Here, we...
Spatial summation of luminance contrast signals has historically been psychophysically measured with stimuli isolated in spatial frequency (i.e., narrowband). Here, we revisit the study of spatial summation with noise patterns that contain the naturalistic 1/fα distribution of contrast across spatial frequency. We measured amplitude spectrum slope (α) discrimination thresholds and verified if sensitivity to α improved according to stimulus size. Discrimination thresholds did decrease with an increase in stimulus size. These data were modeled with a summation model originally designed for narrowband stimuli (i.e., single detecting channel; Baker & Meese, 2011; Meese & Baker, 2011) that we modified to include summation across multiple-differently tuned-spatial frequency channels. To fit our data, contrast gain control weights had to be inversely related to spatial frequency (1/f); thus low spatial frequencies received significantly more divisive inhibition than higher spatial frequencies, which is a similar finding to previous models of broadband contrast perception (Haun & Essock, 2010; Haun & Peli, 2013). We found summation across spatial frequency channels to occur prior to summation across space, channel summation was near linear and summation across space was nonlinear. Our analysis demonstrates that classical psychophysical models can be adapted to computationally define visual mechanisms under broadband visual input, with the adapted models offering novel insight on the integration of signals across channels and space.
Topics: Contrast Sensitivity; Female; Humans; Inhibition, Psychological; Male; Psychophysics; Sensory Thresholds; Space Perception; Young Adult
PubMed: 31100132
DOI: 10.1167/19.5.16 -
Frontiers in Neural Circuits 2020
Topics: Animals; Behavior; Humans; Motion Perception; Neurons; Orientation, Spatial; Space Perception
PubMed: 33324174
DOI: 10.3389/fncir.2020.619073 -
Psychoneuroendocrinology Aug 2022Peripersonal space is the representation of the space near the body. It is implemented by a dedicated multisensory-motor network, whose purpose is to predict and plan...
Peripersonal space is the representation of the space near the body. It is implemented by a dedicated multisensory-motor network, whose purpose is to predict and plan interactions with the environment, and which can vary depending on environmental circumstances. Here, we investigated the effect on the PPS representation of an experimentally induced stress response and compared it to a control, non-stressful, manipulation. We assessed PPS representation in healthy humans, before and after a stressful manipulation, by quantifying visuotactile interactions as a function of the distance from the body, while monitoring salivary cortisol concentration. While PPS representation was not significantly different between the control and experimental group, a relation between cortisol response and changes in PPS emerged within the experimental group. Participants who showed a cortisol stress response presented enhanced visuotactile integration for stimuli close to the body and reduced for far stimuli. Conversely, individuals with a less pronounced cortisol response showed a reduced difference in visuotactile integration between the near and the far space. In our interpretation, physiological stress resulted in a freezing-like response, where multisensory-motor resources are allocated only to the area immediately surrounding the body.
Topics: Humans; Hydrocortisone; Personal Space; Space Perception
PubMed: 35605473
DOI: 10.1016/j.psyneuen.2022.105790 -
Neuron Mar 2014Two reports in this issue of Neuron, Hsieh et al. (2014) and Ezzyat and Davachi (2014), describe fMRI activity patterns in the human hippocampus that correlate with...
Two reports in this issue of Neuron, Hsieh et al. (2014) and Ezzyat and Davachi (2014), describe fMRI activity patterns in the human hippocampus that correlate with memory for temporal context. Analogous activity of neural ensembles recorded from the rodent hippocampus suggests a general model for remembering episodes.
Topics: Female; Form Perception; Hippocampus; Humans; Learning; Male; Memory, Episodic; Pattern Recognition, Visual; Space Perception; Time Perception; Visual Cortex
PubMed: 24607222
DOI: 10.1016/j.neuron.2014.02.034 -
Psychological Bulletin Nov 2015The action-specific perception account holds that people perceive the environment in terms of their ability to act in it. In this view, for example, decreased ability to... (Review)
Review
The action-specific perception account holds that people perceive the environment in terms of their ability to act in it. In this view, for example, decreased ability to climb a hill because of fatigue makes the hill visually appear to be steeper. Though influential, this account has not been universally accepted, and in fact a heated controversy has emerged. The opposing view holds that action capability has little or no influence on perception. Heretofore, the debate has been quite polarized, with efforts largely being focused on supporting one view and dismantling the other. We argue here that polarized debate can impede scientific progress and that the search for similarities between 2 sides of a debate can sharpen the theoretical focus of both sides and illuminate important avenues for future research. In this article, we present a synthetic review of this debate, drawing from the literatures of both approaches, to clarify both the surprising similarities and the core differences between them. We critically evaluate existing evidence, discuss possible mechanisms of action-specific effects, and make recommendations for future research. A primary focus of future work will involve not only the development of methods that guard against action-specific postperceptual effects but also development of concrete, well-constrained underlying mechanisms. The criteria for what constitutes acceptable control of postperceptual effects and what constitutes an appropriately specific mechanism vary between approaches, and bridging this gap is a central challenge for future research.
Topics: Attitude; Cues; Humans; Perception; Space Perception
PubMed: 26501227
DOI: 10.1037/a0039738 -
NeuroImage Feb 2021The perception and measurement of spatial and temporal dimensions have been widely studied. Yet, whether these two dimensions are processed independently is still being...
The perception and measurement of spatial and temporal dimensions have been widely studied. Yet, whether these two dimensions are processed independently is still being debated. Additionally, whether EEG components are uniquely associated with time or space, or whether they reflect a more general measure of magnitude quantity remains unknown. While undergoing EEG, subjects performed a virtual distance reproduction task, in which they were required to first walk forward for an unknown distance or time, and then reproduce that distance or time. Walking speed was varied between estimation and reproduction phases, to prevent interference between distance or time in each estimate. Behaviorally, subject performance was more variable when reproducing time than when reproducing distance, but with similar patterns of accuracy. During estimation, EEG data revealed the contingent negative variation (CNV), a measure previously associated with timing and expectation, tracked the probability of the upcoming interval, for both time and distance. However, during reproduction, the CNV exclusively oriented to the upcoming temporal interval at the start of reproduction, with no change across spatial distances. Our findings indicate that time and space are neurally separable dimensions, with the CNV both serving a supramodal role in temporal and spatial expectation, yet an exclusive role in preparing duration reproduction.
Topics: Adolescent; Adult; Brain; Contingent Negative Variation; Electroencephalography; Female; Humans; Male; Space Perception; Time Perception; Young Adult
PubMed: 33290808
DOI: 10.1016/j.neuroimage.2020.117607 -
Spatial Vision 1995This paper reviews empirical evidence for the detection of visual symmetries and explanatory theories and models of symmetry detection. First, mirror symmetry is... (Review)
Review
This paper reviews empirical evidence for the detection of visual symmetries and explanatory theories and models of symmetry detection. First, mirror symmetry is compared to other types of symmetry. The idea that symmetry detection is preattentive is then discussed and other roles that attention might play in symmetry detection are considered. The major part of the article consists of a critical examination of the extensive literature about the effects on symmetry detection of several major factors such as the orientation of the symmetry axis, the location of the stimulus in the visual field, grouping, and perturbations. Constraints on plausible models of symmetry detection are derived from this rich database and several proposals are evaluated against it. As a result of bringing this research together, open questions and remaining gaps to be filled by future research are identified.
Topics: Animals; Attention; Form Perception; Humans; Models, Biological; Orientation; Pattern Recognition, Visual; Psychophysics; Space Perception
PubMed: 7626549
DOI: 10.1163/156856895x00098