Positional acuity with chromatic stimuli

Morgan, Michael J.; Aiba, Thomas S.

doi:10.1016/0042-6989(85)90175-0

Cited by 66 publications

(33 citation statements)

References 12 publications

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“…Although it is not possible to completely isolate M and P responses, the luminance CS measured in this way at threshold can be expected to predominantly reflect the sensitivity of the M pathway and the color CS that of the P pathway. 13 Thus it is reasonable to infer that sensitivity of the P pathway is reduced in relation to that of the M pathway for amblyopic and fellow eyes. Some previous studies have described an increase in achromatic CS in the fellow eye of amblyopes with strabismus compared with control eyes, 19,20 whereas others have described reduced function.…”

Section: Discussionmentioning

confidence: 99%

Differential Changes of Magnocellular and Parvocellular Visual Function in Early- and Late-Onset Strabismic Amblyopia

Davis

Sloper

Neveu

et al. 2006

Invest. Ophthalmol. Vis. Sci.

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PURPOSE.Studies in nonhuman primates show that monocular visual deprivation starting at different ages has different effects on cells in the parvocellular and magnocellular laminae of the lateral geniculate nucleus. The present study used color and luminance contrast sensitivity (CS) measurements to look for differences in parvocellular-and magnocellular-related visual function in human subjects with strabismic amblyopia. METHODS. Fifteen subjects with early-and 14 with late-onset strabismic amblyopia and similar ranges of visual acuity were studied, together with 15 subjects with normal vision. Contrast sensitivities were measured to an equiluminant (L-M conemodulated) grating with slow onset and an achromatic (LϩM cone-modulated) 0.8-cpd grating with rapid onset using an adaptive method. RESULTS. Luminance and color CS were lower in the amblyopic eyes than in the fellow eyes of all amblyopes. For luminance CS, this was due both to an increase in sensitivity of the fellow eye and to a reduction in sensitivity in the amblyopic eye. Color CS was greatly reduced in the amblyopic and fellow eyes of subjects with strabismic amblyopia of early-and late onset compared with subjects with normal vision. The reduction in color CS compared with luminance CS was significantly greater in eyes with late-rather than early-onset amblyopia. CONCLUSIONS. Parvocellular and magnocellular function are differentially affected in the amblyopic and fellow eyes of subjects with strabismic amblyopia. The difference is more marked in late-onset amblyopia than in early-onset amblyopia. (Invest Ophthalmol Vis Sci. 2006;47:4836 -4841)

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Section: Discussionmentioning

confidence: 99%

Differential Changes of Magnocellular and Parvocellular Visual Function in Early- and Late-Onset Strabismic Amblyopia

Davis

Sloper

Neveu

et al. 2006

Invest. Ophthalmol. Vis. Sci.

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“…The fact that spatially distant nonoriented color cells are strongly correlated suggests a possible role for these interactions in the propagation of fill-in of color as a surface property. Not only would color-matching be important for the "coloring in" of a bounded surface, but a high degree of spatial precision would not be necessary (Morgan and Aiba 1985). In contrast, spatial overlap is apparently crucial for the interaction between nonoriented V1 cells and oriented V2 cells.…”

Section: Color Visionmentioning

confidence: 99%

Specificity of Color Connectivity Between Primate V1 and V2

Roe

Ts’o

1999

Journal of Neurophysiology

103

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Roe, Anna Wang and Daniel Y. Ts'o. Specificity of color connectivity between primate V1 and V2. J. Neurophysiol. 82: 2719Neurophysiol. 82: -2730Neurophysiol. 82: , 1999. To examine the functional interactions between the color and form pathways in the primate visual cortex, we have examined the functional connectivity between pairs of color oriented and nonoriented V1 and V2 neurons in Macaque monkeys. Optical imaging maps for color selectivity, orientation preference, and ocular dominance were used to identify specific functional compartments within V1 and V2 (blobs and thin stripes). These sites then were targeted with multiple electrodes, single neurons isolated, and their receptive fields characterized for orientation selectivity and color selectivity. Functional interactions between pairs of V1 and V2 neurons were inferred by cross-correlation analysis of spike firing. Three types of color interactions were studied: nonoriented V1/nonoriented V2 cell pairs, nonoriented V1/oriented V2 cell pairs, and oriented V1/nonoriented V2 cell pairs. In general, interactions between V1 and V2 neurons are highly dependent on color matching. Different cell pairs exhibited differing dependencies on spatial overlap. Interactions between nonoriented color cells in V1 and V2 are dependent on color matching but not on receptive field overlap, suggesting a role for these interactions in coding of color surfaces. In contrast, interactions between nonoriented V1 and oriented V2 color cells exhibit a strong dependency on receptive field overlap, suggesting a separate pathway for processing of color contour information. Yet another pattern of connectivity was observed between oriented V1 and nonoriented V2 cells; these cells exhibited interactions only when receptive fields were far apart and failed to interact when spatially overlapped. Such interactions may underlie the induction of color and brightness percepts from border contrasts. Our findings thus suggest the presence of separate color pathways between V1 and V2, each with differing patterns of convergence and divergence and distinct roles in color and form vision. I N T R O D U C T I O NCross-correlation techniques have been used to reveal the cooperative computations between groups of neurons both within and between areas. In the case of the lateral geniculate nucleus and primary visual cortex (V1), correlated firing reveals pairs of neurons with overlapping receptive fields, i.e., computation of spatial similarity (Reid and Alonso 1995; Tanaka 1985). Within V1, correlated firing is found between neurons with matching orientation and color preferences (Ts'o and Gilbert 1988;Ts'o et al. 1986). Thus far, little is known about the computations performed in V2 nor the relationship of the functional maps to those computations. By studying pairs of V1-V2 neurons, identified according to anatomic location and classified by color and orientation, we have begun to address the question of what the relevant computations between V1 and V2 may be.Within the primate visual pathway,...

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“…Similar to perceptual phenomena (e.g., vernier acuity; Morgan & Aiba, 1985), the capture of attention by certain visual events is also compromised if the inducing stimulus is not accompanied by a luminance change. For instance, employing a variant of the precueing paradigm discussed above, Cole, Kentridge, and Heywood (2005) presented a colour change to one of two objects located in a visual display.…”

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confidence: 99%

Non-transient luminance changes do not capture attention

Cole

Kuhn

Skarratt

2011

Atten Percept Psychophys

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The processing of luminance change is a ubiquitous feature of the human visual system and provides the basis for the rapid orienting of attention to potentially important events (e.g., motion onset, object onset). However, despite its importance for attentional capture, it is not known whether a luminance change attracts attention solely because of its status as a sensory transient or can attract attention at a relatively high cognitive level. In a series of six experiments, we presented visual displays in which a single object underwent a luminance change that was either visible or obscured by a mask. A target then appeared either at the change location or elsewhere. The results showed that the luminance change attracted attention only in the visible condition. This was even observed with the largest change we could generate (> 75 cd/m 2 ). These data suggest that the importance of a luminance change is only in its status as a low-level sensory transient.

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Positional acuity with chromatic stimuli

Cited by 66 publications

References 12 publications

Differential Changes of Magnocellular and Parvocellular Visual Function in Early- and Late-Onset Strabismic Amblyopia

Differential Changes of Magnocellular and Parvocellular Visual Function in Early- and Late-Onset Strabismic Amblyopia

Specificity of Color Connectivity Between Primate V1 and V2

Non-transient luminance changes do not capture attention

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