Reliability analysis of individual visual P1 and N1 maps indicates the heterogeneous topographies involved in early visual processing among human subjects

Performance of human subjects in a wide variety of early visual processing tasks improves with practice. HyperBF networks (Poggio and Girosi 1990) constitute a mathematically well-founded framework for understanding such improvement in performance, or perceptual learning, in the class of tasks known as visual hyperacuity. The present article concentrates on two issues raised by the recent psychophysical and computational findings reported in Poggio et al. (1992b) and Fahle and Edelman (1992). First, we develop a biologically plausible extension of the HyperBF model that takes into account basic features of the functional architecture of early vision. Second, we explore various learning modes that can coexist within the HyperBF framework and focus on two unsupervised learning rules that may be involved in hyperacuity learning. Finally, we report results of psychophysical experiments that are consistent with the hypothesis that activity-dependent presynaptic amplification may be involved in perceptual learning in hyperacuity.

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Measuring and modeling selective attention in early visual processing

PsycEXTRA Dataset ◽

10.1037/e536982012-174 ◽

1997 ◽

Cited By ~ 1

Author(s):

George Sperling ◽

Shui-I. Shih

Keyword(s):

Selective Attention ◽

Visual Processing ◽

Early Visual Processing

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Directional selectivity and its use in early visual processing

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1981.0001 ◽

1981 ◽

Vol 211 (1183) ◽

pp. 151-180 ◽

Cited By ~ 348

Keyword(s):

Visual Processing ◽

Visual Motion ◽

Time Derivative ◽

Receptive Fields ◽

Specific Model ◽

Zero Crossings ◽

Second Stage ◽

Early Visual Processing ◽

Local Direction ◽

Zero Values

The construction of directionally selective units, and their use in the processing of visual motion, are considered. The zero crossings of ∇ 2 G(x, y) ∗ I(x, y) are located, as in Marr & Hildreth (1980). That is, the image is filtered through centre-surround receptive fields, and the zero values in the output are found. In addition, the time derivative ∂[∇ 2 G(x, y) ∗ l(x, y) ]/∂ t is measured at the zero crossings, and serves to constrain the local direction of motion to within 180°. The direction of motion can be determined in a second stage, for example by combining the local constraints. The second part of the paper suggests a specific model of the information processing by the X and Y cells of the retina and lateral geniculate nucleus, and certain classes of cortical simple cells. A number of psychophysical and neurophysiological predictions are derived from the theory.

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Effects of emotional conditioning on early visual processing: Temporal dynamics revealed by ERP single-trial analysis

Human Brain Mapping ◽

10.1002/hbm.21259 ◽

2011 ◽

Vol 33 (4) ◽

pp. 909-919 ◽

Cited By ~ 10

Author(s):

Yuelu Liu ◽

Andreas Keil ◽

Mingzhou Ding

Keyword(s):

Visual Processing ◽

Temporal Dynamics ◽

Single Trial ◽

Single Trial Analysis ◽

Early Visual Processing ◽

Trial Analysis ◽

Emotional Conditioning

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Wide-Field Feedback Neurons Dynamically Tune Early Visual Processing

Neuron ◽

10.1016/j.neuron.2014.04.023 ◽

2014 ◽

Vol 82 (4) ◽

pp. 887-895 ◽

Cited By ~ 35

Author(s):

John C. Tuthill ◽

Aljoscha Nern ◽

Gerald M. Rubin ◽

Michael B. Reiser

Keyword(s):

Visual Processing ◽

Wide Field ◽

Early Visual Processing

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Priming from the Attentional Blink: A Failure to Extract Visual Tokens but Not Visual Types

Psychological Science ◽

10.1111/j.1467-9280.1997.tb00689.x ◽

1997 ◽

Vol 8 (2) ◽

pp. 95-100 ◽

Cited By ~ 134

Author(s):

Kimron Shapiro ◽

Jon Driver ◽

Robert Ward ◽

Robyn E. Sorensen

Keyword(s):

Attentional Blink ◽

Semantic Priming ◽

Visual Processing ◽

Visual Representation ◽

Stimulus Processing ◽

Visual Events ◽

Early Visual Processing ◽

Location Detection ◽

Subsequent Target ◽

Initial Target

When people must detect several targets in a very rapid stream of successive visual events at the same location, detection of an initial target induces misses for subsequent targets within a brief period. This attentional blink may serve to prevent interruption of ongoing target processing by temporarily suppressing vision for subsequent stimuli. We examined the level at which the internal blink operates, specifically, whether it prevents early visual processing or prevents quite substantial processing from reaching awareness. Our data support the latter view. We observed priming from missed letter targets, benefiting detection of a subsequent target with the same identity but a different case. In a second study, we observed semantic priming from word targets that were missed during the blink. These results demonstrate that attentional gating within the blink operates only after substantial stimulus processing has already taken place. The results are discussed in terms of two forms of visual representation, namely, types and tokens.

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Spatial frequency analsis in early visual processing

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1980.0079 ◽

1980 ◽

Vol 290 (1038) ◽

pp. 11-22 ◽

Cited By ~ 54

Keyword(s):

Spatial Frequency ◽

Visual Processing ◽

Spatial Information ◽

Multiple Channels ◽

Low Contrast ◽

Local Sign ◽

Early Visual Processing ◽

Low Luminance ◽

Lowered Sensitivity ◽

Prior Adaptation

The existence of multiple channels, or multiple receptive field sizes, in the visual system does not commit us to any particular theory of spatial encoding in vision. However, distortions of apparent spatial frequency and width in a wide variety of conditions favour the idea that each channel carries a width- or frequency-related code or ‘label’ rather than a ‘local sign’ or positional label. When distortions of spatial frequency occur without prior adaptation (e.g. at low contrast or low luminance) they are associated with lowered sensitivity, and may be due to a mismatch between the perceptual labels and the actual tuning of the channels. A low-level representation of retinal space could be constructed from the spatial information encoded by the channels, rather than being projected intact from the retina.

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