scholarly journals Visual field map clusters in human frontoparietal cortex

eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Wayne E Mackey ◽  
Jonathan Winawer ◽  
Clayton E Curtis

The visual neurosciences have made enormous progress in recent decades, in part because of the ability to drive visual areas by their sensory inputs, allowing researchers to define visual areas reliably across individuals and across species. Similar strategies for parcellating higher-order cortex have proven elusive. Here, using a novel experimental task and nonlinear population receptive field modeling, we map and characterize the topographic organization of several regions in human frontoparietal cortex. We discover representations of both polar angle and eccentricity that are organized into clusters, similar to visual cortex, where multiple gradients of polar angle of the contralateral visual field share a confluent fovea. This is striking because neural activity in frontoparietal cortex is believed to reflect higher-order cognitive functions rather than external sensory processing. Perhaps the spatial topography in frontoparietal cortex parallels the retinotopic organization of sensory cortex to enable an efficient interface between perception and higher-order cognitive processes. Critically, these visual maps constitute well-defined anatomical units that future studies of frontoparietal cortex can reliably target.

2016 ◽  
Author(s):  
Wayne E. Mackey ◽  
Jonathan Winawer ◽  
Clayton E. Curtis

SUMMARYThe visual neurosciences have made enormous progress in recent decades, in part because of the ability to drive visual areas by their sensory inputs, allowing researchers to reliably define visual areas across individuals and across species. Similar strategies for parceling higher-order cortex have proven elusive. Here, using a novel experimental task and nonlinear population receptive field modeling we map and characterize the topographic organization of several regions in human frontoparietal cortex. We discover maps of both polar angle and eccentricity that are organized into clusters, similar to visual cortex, where multiple maps of polar angle of the contralateral visual field share a confluent fovea. This is striking because neural activity in frontoparietal cortex is believed to reflect higher-order cognitive functions rather than external sensory processing. Perhaps the spatial topography in frontoparietal cortex parallels the retinotopic organization of sensory cortex to enable an efficient interface between perception and higher-order cognitive processes. Critically, these visual maps constitute well-defined anatomical units that future study of frontoparietal cortex can reliably target.


2007 ◽  
Vol 24 (6) ◽  
pp. 857-874 ◽  
Author(s):  
THOMAS FITZGIBBON ◽  
BRETT A. SZMAJDA ◽  
PAUL R. MARTIN

The thalamic reticular nucleus (TRN) supplies an important inhibitory input to the dorsal thalamus. Previous studies in non-primate mammals have suggested that the visual sector of the TRN has a lateral division, which has connections with first-order (primary) sensory thalamic and cortical areas, and a medial division, which has connections with higher-order (association) thalamic and cortical areas. However, the question whether the primate TRN is segregated in the same manner is controversial. Here, we investigated the connections of the TRN in a New World primate, the marmoset (Callithrix jacchus). The topography of labeled cells and terminals was analyzed following iontophoretic injections of tracers into the primary visual cortex (V1) or the dorsal lateral geniculate nucleus (LGNd). The results show that rostroventral TRN, adjacent to the LGNd, is primarily connected with primary visual areas, while the most caudal parts of the TRN are associated with higher order visual thalamic areas. A small region of the TRN near the caudal pole of the LGNd (foveal representation) contains connections where first (lateral TRN) and higher order visual areas (medial TRN) overlap. Reciprocal connections between LGNd and TRN are topographically organized, so that a series of rostrocaudal injections within the LGNd labeled cells and terminals in the TRN in a pattern shaped like rostrocaudal overlapping “fish scales.” We propose that the dorsal areas of the TRN, adjacent to the top of the LGNd, represent the lower visual field (connected with medial LGNd), and the more ventral parts of the TRN contain a map representing the upper visual field (connected with lateral LGNd).


Author(s):  
Xiaolian Li ◽  
Qi Zhu ◽  
Wim Vanduffel

AbstractThe visuotopic organization of dorsal visual cortex rostral to area V2 in primates has been a longstanding source of controversy. Using sub-millimeter phase-encoded retinotopic fMRI mapping, we recently provided evidence for a surprisingly similar visuotopic organization in dorsal visual cortex of macaques compared to previously published maps in New world monkeys (Zhu and Vanduffel, Proc Natl Acad Sci USA 116:2306–2311, 2019). Although individual quadrant representations could be robustly delineated in that study, their grouping into hemifield representations remains a major challenge. Here, we combined in-vivo high-resolution myelin density mapping based on MR imaging (400 µm isotropic resolution) with fine-grained retinotopic fMRI to quantitatively compare myelin densities across retinotopically defined visual areas in macaques. Complementing previously documented differences in populational receptive-field (pRF) size and visual field signs, myelin densities of both quadrants of the dorsolateral posterior area (DLP) and area V3A are significantly different compared to dorsal and ventral area V3. Moreover, no differences in myelin density were observed between the two matching quadrants belonging to areas DLP, V3A, V1, V2 and V4, respectively. This was not the case, however, for the dorsal and ventral quadrants of area V3, which showed significant differences in MR-defined myelin densities, corroborating evidence of previous myelin staining studies. Interestingly, the pRF sizes and visual field signs of both quadrant representations in V3 are not different. Although myelin density correlates with curvature and anticorrelates with cortical thickness when measured across the entire cortex, exactly as in humans, the myelin density results in the visual areas cannot be explained by variability in cortical thickness and curvature between these areas. The present myelin density results largely support our previous model to group the two quadrants of DLP and V3A, rather than grouping DLP- with V3v into a single area VLP, or V3d with V3A+ into DM.


2021 ◽  
pp. 155982762110428
Author(s):  
Purva Jain ◽  
Jonathan T. Unkart ◽  
Fabio B. Daga ◽  
Linda Hill

Limited research exists examining self-perceived vision and driving ability among individuals with glaucoma, and this study assessed the relationship between glaucoma, visual field, and visual acuity with driving capability. 137 individuals with glaucoma and 75 healthy controls were asked to evaluate self-rated vision, self-perceived driving ability, and self-perceived distracted driving. Visual acuity and visual field measurements were also obtained. Multivariable linear regressions were run to test each visual measure with driving outcomes. The average age was 72.2 years, 57.3% were male, and 72.5% were White. There were significant associations for a one-point increase in visual field and quality of corrected vision (RR = 1.06; 95% CI = 1.03–1.10), day vision (RR = 1.05; 95% CI = 1.03–1.08), night vision (RR = 1.08; 95% CI = 1.05–1.13), visual acuity score and higher quality of corrected of vision (RR = .41; 95% CI = .22-.77), day vision (RR = .39; 95% CI=.22–.71), and night vision (RR = .41; 95% CI = .18–.94); visual acuity score and ability to drive safely compared to other drivers your age (RR = .53; 95% CI = .29–.96). Individuals with poorer visual acuity and visual fields rate their vision and ability to drive lower than those with better vision, and this information will allow clinicians to understand where to target interventions to enhance safe driving practices.


2010 ◽  
Vol 104 (4) ◽  
pp. 2075-2081 ◽  
Author(s):  
Lars Strother ◽  
Adrian Aldcroft ◽  
Cheryl Lavell ◽  
Tutis Vilis

Functional MRI (fMRI) studies of the human object recognition system commonly identify object-selective cortical regions by comparing blood oxygen level–dependent (BOLD) responses to objects versus those to scrambled objects. Object selectivity distinguishes human lateral occipital cortex (LO) from earlier visual areas. Recent studies suggest that, in addition to being object selective, LO is retinotopically organized; LO represents both object and location information. Although LO responses to objects have been shown to depend on location, it is not known whether responses to scrambled objects vary similarly. This is important because it would suggest that the degree of object selectivity in LO does not vary with retinal stimulus position. We used a conventional functional localizer to identify human visual area LO by comparing BOLD responses to objects versus scrambled objects presented to either the upper (UVF) or lower (LVF) visual field. In agreement with recent findings, we found evidence of position-dependent responses to objects. However, we observed the same degree of position dependence for scrambled objects and thus object selectivity did not differ for UVF and LVF stimuli. We conclude that, in terms of BOLD response, LO discriminates objects from non-objects equally well in either visual field location, despite stronger responses to objects in the LVF.


1993 ◽  
Vol 10 (1) ◽  
pp. 131-158 ◽  
Author(s):  
Helen Sherk ◽  
Kathleen A. Mulligan

AbstractLateral suprasylvian visual cortex in the cat has been studied extensively, but its retinotopic organization remains controversial. Although some investigators have divided this region into many distinct areas, others have argued for a simpler organization. A clear understanding of the region’s retinotopic organization is important in order to define distinct areas that are likely to subserve unique visual functions. We therefore reexamined the map of the lower visual field in the striate-recipient region of lateral suprasylvian cortex, a region we refer to as the lateral suprasylvian area, LS.A dual mapping approach was used. First, receptive fields were plotted at numerous locations along closely spaced electrode penetrations; second, different anterograde tracers were injected at retinotopically identified sites in area 17, yielding patches of label in LS. To visualize the resulting data, suprasylvian cortex was flattened with the aid of a computer.Global features of the map reported in many earlier studies were confirmed. Central visual field was represented posteriorly, and elevations generally shifted downward as one moved anteriorly. Often (though not always) there was a progression from peripheral locations towards the vertical meridian as the electrode moved down the medial suprasylvian bank.The map had some remarkable characteristics not previously reported in any map in the cat. The vertical meridian’s representation was split into two pieces, separated by a gap, and both pieces were partially internalized within the map. Horizontal meridian occupied the gap. The area centralis usually had a dual representation along the posterior boundary of the lower field representation, and other fragments of visual field were duplicated as well. Finally, magnification appeared to change abruptly and unexpectedly, so that compressed regions of representation adjoined expanded regions. Despite its complexity, we found the map to be more orderly than previously thought. There was no clearcut retinotopic basis on which to subdivide LS’s lower field representation into distinct areas.


i-Perception ◽  
2020 ◽  
Vol 11 (4) ◽  
pp. 204166952093840
Author(s):  
Li Zhaoping

Consider a gray field comprising pairs of vertically aligned dots; in each pair, one dot is white the other black. When viewed in a peripheral visual field, these pairs appear horizontally aligned. By the Central-Peripheral Dichotomy, this flip tilt illusion arises because top-down feedback from higher to lower visual cortical areas is too weak or absent in the periphery to veto confounded feedforward signals from the primary visual cortex (V1). The white and black dots in each pair activate, respectively, on and off subfields of V1 neural receptive fields. However, the sub-fields’ orientations, and the preferred orientations, of the most activated neurons are orthogonal to the dot alignment. Hence, V1 reports the flip tilt to higher visual areas. Top-down feedback vetoes such misleading reports, but only in the central visual field.


1990 ◽  
Vol 4 (3) ◽  
pp. 205-216 ◽  
Author(s):  
W. Fries

AbstractThe projection from striate and prestriate visual cortex to the pontine nuclei has been studied in the macaque monkey by means of anterograde tracer techniques in order to assess the contribution of anatomically and functionally distinct visual cortical areas to the cortico-ponto-cerebellar loop. No projection to the pons was found from central or paracentral visual-field representations of V1 (striate cortex) or prestriate visual areas V2, and V4. Small patches of terminal labeling occurred after injections of tracer into more peripheral parts of V1, V2 and V3, and into V3A. The terminal fields were located most dorsolaterally in the anterior to middle third of the pons and were quite restricted in their rostro-caudal extent. Injections of V5, however, yielded substantial terminal labeling, stretching longitudinally throughout almost the entire pons. This projection could be demonstrated to arise from parts of V5 receiving input from central visual-field representations of striate cortex, whereas parts of V4 receiving similarly central visual-field input had no detectable projection to the pons. Its distribution may overlap to a large extent with the termination of tecto-pontine fibers and with the termination of fibers from visual areas in the medial bank (area V6 or P0) and lateral bank (area LIP) of the intraparietal sulcus, as well as from frontal eye fields (FEF). It appears that the main information relayed to the cerebellum by the visual corticopontine projection is related to movement in the field of view.


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