scholarly journals Linked changes in visual acuity, cortical population receptive field size, visual field map size, and retinal thickness in healthy human aging

2021 ◽  
Author(s):  
Maria Fatima Silva ◽  
Ben Harvey ◽  
Lília Jorge ◽  
Nádia Canário ◽  
Fátima Machado ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Receptive Field ◽  
Retinal Thickness ◽  
Field Size ◽  
Human Aging ◽  
Healthy Human ◽  
Field Representation ◽  
Surface Areas ◽  
Retinal Structure

Abstract Healthy human aging is associated with a deterioration of visual acuity, retinal thinning, visual field map shrinkage and increasing population receptive field sizes. Here we ask how these changes are related to each other in a cross-sectional sample of fifty healthy adults aged 20-80 years. We therefore hypothesized that age-related loss of macular retinal ganglion cells may lead to decreased visual field map sizes, and both may lead to increased pRF sizes in the cortical central visual field representation. We measured our participants’ perceptual corrected visual acuity using standard ophthalmological letter charts. We then measured their early visual field map (V1, V2 and V3) functional population receptive field (pRF) sizes and structural surface areas using fMRI, and their retinal structure using high-definition optical coherence tomography. With increasing age visual acuity decreased, pRF sizes increased, visual field maps surface areas decreased, and retinal thickness decreased. Among these measures, only functional pRF sizes predicted perceptual visual acuity, and Bayesian statistics support a null relationship between visual acuity and cortical or retinal structure. However, pRF sizes were in turn predicted by cortical structure only (visual field map surface areas), which were only predicted by retinal structure (thickness). These results suggest that linked disruptions of neural structure and function throughout the early visual system underlie the deterioration of perceptual visual acuity in healthy aging.

scholarly journals Simultaneous changes in visual acuity, cortical population receptive field size, visual field map size, and retinal thickness in healthy human aging

2021 ◽  
Author(s):  
Maria Fatima Silva ◽  
Ben M. Harvey ◽  
Lília Jorge ◽  
Nádia Canário ◽  
Fátima Machado ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Receptive Field ◽  
Retinal Thickness ◽  
Field Size ◽  
Human Aging ◽  
Healthy Human ◽  
Field Representation ◽  
Surface Areas ◽  
Retinal Structure

AbstractHealthy human aging is associated with a deterioration of visual acuity, retinal thinning, visual field map shrinkage and increasing population receptive field sizes. Here we ask how these changes are related to each other in a cross-sectional sample of fifty healthy adults aged 20–80 years. We hypothesized that age-related loss of macular retinal ganglion cells may lead to decreased visual field map sizes, and both may lead to increased pRF sizes in the cortical central visual field representation. We measured our participants’ perceptual corrected visual acuity using standard ophthalmological letter charts. We then measured their early visual field map (V1, V2 and V3) functional population receptive field (pRF) sizes and structural surface areas using fMRI, and their retinal structure using high-definition optical coherence tomography. With increasing age visual acuity decreased, pRF sizes increased, visual field maps surface areas (but not whole-brain surface areas) decreased, and retinal thickness decreased. Among these measures, only functional pRF sizes predicted perceptual visual acuity, and Bayesian statistics support a null relationship between visual acuity and cortical or retinal structure. However, pRF sizes were in turn predicted by cortical structure only (visual field map surface areas), which were only predicted by retinal structure (thickness). These results suggest that simultaneous disruptions of neural structure and function throughout the early visual system may underlie the deterioration of perceptual visual acuity in healthy aging.

scholarly journals Linked deterioration of early visual perception, function and structure in healthy human aging

2020 ◽  
Author(s):  
Maria Fatima Silva ◽  
Ben M Harvey ◽  
Lília Jorge ◽  
Nádia Canário ◽  
Fátima Machado ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Visual Perception ◽  
Healthy Aging ◽  
Healthy Human ◽  
Cortical Structure ◽  
Surface Areas ◽  
Structural Deterioration ◽  
Age Related ◽  
Retinal Structure

SummaryLow-level visual perception deteriorates during healthy aging. We hypothesized that age-related retinal and cortical structure deteriorations affect perception through specific disruptions of neural function. We measured perceptual visual acuity in fifty healthy adults aged 20-80 years. We then measured these participants’ early visual field map (V1, V2 and V3) functional population receptive field (pRF) sizes and structural surface areas using fMRI, and their retinal structure using high-definition optical coherence tomography. With increasing age visual acuity decreased, pRF sizes increased, visual field maps surface areas decreased, and retinal thickness decreased. Among these measures, only functional pRF sizes predicted perceptual visual acuity. PRF sizes were in turn predicted by cortical structure only (surface areas), which were only predicted by retinal structure (thickness). We propose that age-related retinal structural deterioration disrupts cortical structure, thereby disrupting cortical functional neural interactions that normally sharpen visual position selectivity: the resulting functional disruption underlies age-related perceptual deterioration.

scholarly journals Visual performance in behaving cats after prenatal unilateral enucleation

1993 ◽  
Vol 90 (23) ◽  
pp. 11142-11146 ◽  
Author(s):  
S Bisti ◽  
C Trimarchi
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Receptive Field ◽  
Receptive Fields ◽  
Direction Selectivity ◽  
Visual Performance ◽  
Field Size ◽  
Electrophysiological Recordings ◽  
Severe Impairment ◽  
Orientation Columns

Prenatal unilateral enucleation in mammals causes an extensive anatomical reorganization of visual pathways. The remaining eye innervates the entire extent of visual subcortical and cortical areas. Electrophysiological recordings have shown that the retino-geniculate connections are retinotopically organized and geniculate neurones have normal receptive field properties. In area 17 all neurons respond to stimulation of the remaining eye and retinotopy, orientation columns, and direction selectivity are maintained. The only detectable change is a reduction in receptive field size. Are these changes reflected in the visual behavior? We studied visual performance in cats unilaterally enucleated 3 weeks before birth (gestational age at enucleation, 39-42 days). We tested behaviorally the development of visual acuity and, in the adult, the extension of the visual field and the contrast sensitivity. We found no difference between prenatal monocularly enucleated cats and controls in their ability to orient to targets in different positions of the visual field or in their visual acuity (at any age). The major difference between enucleated and control animals was in contrast sensitivity:prenatal enucleated cats present a loss in sensitivity for gratings of low spatial frequency (below 0.5 cycle per degree) as well as a slight increase in sensitivity at middle frequencies. We conclude that prenatal unilateral enucleation causes a selective change in the spatial performance of the remaining eye. We suggest that this change is the result of a reduction in the number of neurones with large receptive fields, possibly due to a severe impairment of the Y system.

scholarly journals Visual Field Representation in Striate and Prestriate Cortices of a Prosimian Primate (Galago garnetti)

1997 ◽  
Vol 77 (6) ◽  
pp. 3193-3217 ◽  
Author(s):  
Marcello G. P. Rosa ◽  
Vivien A. Casagrande ◽  
Todd Preuss ◽  
Jon H. Kaas
Keyword(s):  
Visual Field ◽  
Receptive Field ◽  
Field Size ◽  
Horizontal Meridian ◽  
Magnification Factor ◽  
Field Representation ◽  
Lower Quadrant ◽  
Visual Areas ◽  
Area Centralis ◽  
Order Representation

Rosa, Marcello G. P., Vivien A. Casagrande, Todd Preuss, and Jon H. Kaas. Visual field representation in striate and prestriate cortices of a prosimian primate ( Galago garnetti). J. Neurophysiol. 77: 3193–3217, 1997. Microelectrode mapping techniques were used to study the visuotopic organization of the first and second visual areas (V1 and V2, respectively) in anesthetized Galago garnetti, a lorisiform prosimian primate. 1) V1 occupies ∼200 mm2 of cortex, and is pear shaped, rather than elliptical as in simian primates. Neurons in V1 form a continuous (1st-order) representation of the visual field, with the vertical meridian forming most of its perimeter. The representation of the horizontal meridian divides V1 into nearly equal sectors representing the upper quadrant ventrally, and the lower quadrant dorsally. 2) The emphasis on representation of central vision is less marked in Galago than in simian primates, both diurnal and nocturnal. The decay of cortical magnification factor with increasing eccentricity is almost exactly counterbalanced by an increase in average receptive field size, such that a point anywhere in the visual field is represented by a compartment of similar diameter in V1. 3) Although most of the cortex surrounding V1 corresponds to V2, one-quarter of the perimeter of V1 is formed by agranular cortex within the rostral calcarine sulcus, including area prostriata. Although under our recording conditions virtually every recording site in V2 yielded visually responsive cells, only a minority of those in area prostriata revealed such responses. 4) V2 forms a cortical belt of variable width, being narrowest (∼1 mm) in the representation of the area centralis and widest (2.5–3 mm) in the representation of the midperiphery (>20° eccentricity) of the visual field. V2 forms a second-order representation of the visual field, with the area centralis being represented laterally and the visual field periphery medially, near the calcarine sulcus. Unlike in simians, the line of field discontinuity in Galago V2 does not exactly coincide with the horizontal meridian: a portion of the lower quadrant immediately adjacent to the horizontal meridian is represented at the rostral border of ventral V2, instead of in dorsal V2. Despite the absence of cytochrome oxidase stripes, the visual field map in Galago V2 resembles the ones described in simians in that the magnification factor is anisotropic. 5) Receptive field progressions in cortex rostral to dorsal V2 suggest the presence of a homologue of the dorsomedial area, including representations of both quadrants of the visual field. These results indicate that many aspects of organization of V1 and V2 in simian primates are shared with lorisiform prosimians, and are therefore likely to have been present in the last common ancestor of living primates. However, some aspects of organization of the caudal visual areas in Galago are intermediate between nonprimates and simian primates, reflecting either an intermediate stage of differentiation or adaptations to a nocturnal niche. These include the shape and the small size of V1 and V2, the modest degree of emphasis on central visual field representation, and the relatively large area prostriata.

scholarly journals Effect of smoking on macular function and retinal structure in retinitis pigmentosa

2020 ◽  
Vol 2 (2) ◽  
Author(s):  
Akio Oishi ◽  
Kazunori Noda ◽  
Johannes Birtel ◽  
Masahiro Miyake ◽  
Atsuyasu Sato ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Visual Field ◽  
Retinitis Pigmentosa ◽  
Retinal Thickness ◽  
Central Retinal Thickness ◽  
Smoking History ◽  
Macular Function ◽  
Ellipsoid Zone ◽  
Zone Width ◽  
Age And Sex

Abstract Retinitis pigmentosa is an inherited neurodegenerative disease of the retina. We investigated smoking as a modifiable environmental factor for the progression of this currently untreatable disease. Clinical data, smoking history, macular function and morphology including visual acuity, visual field sensitivity, ellipsoid zone width and central retinal thickness were investigated. Association between pack × years and these parameters were evaluated using generalized estimating equation models to adjust confounding factors such as age and sex. A total of 410 patients with retinitis pigmentosa (≥20 years old; 209 female) were included, 164 had a smoking history. Patients without smoking history revealed a better visual acuity than smokers (0.39 versus 0.57, P = 0.001). The pack × years index was associated with worse visual acuity and thinner central retinal thickness after adjusting for age and sex (P = 0.0047 and 0.0099, respectively). Visual field and ellipsoid zone width showed a non-significant decline with increasing pack × years. This study indicates an association of smoking with worse macular function and structural integrity in retinitis pigmentosa patients, and hence a potential detrimental effect of smoking on the disease course.

Visual receptive-field properties of single neurons in cat's ventral lateral geniculate nucleus

1977 ◽  
Vol 40 (2) ◽  
pp. 390-409 ◽  
Author(s):  
P. D. Spear ◽  
D. C. Smith ◽  
L. L. Williams
Keyword(s):  
Visual Field ◽  
Receptive Field ◽  
Lateral Geniculate Nucleus ◽  
Receptive Fields ◽  
Field Size ◽  
Dorsal Lateral Geniculate Nucleus ◽  
Lower Visual Field ◽  
Visual Receptive Field ◽  
Lateral Geniculate ◽  
Receptive Field Properties

1. Visual receptive-field characteristics were determined for 154 cells in the ventral lateral geniculate nucleus (VLG) of cats anesthetized with nitrous oxide. All cells were verified histologically to be within the VLG. Responses of 182 cells from laminae A and A1 of the dorsal lateral geniculate nucleus (DLG) were tested for comparison. 2. The VLG cells could be grouped into one of seven classes according to their responses to light stimulation. Twenty-seven percent of the cells had uniform receptive fields. They responded maximally to stationary stimuli flashed on or off anywhere within the receptive field and showed no evidence for antagonistic surround mechanisms. About 19.5% of the VLG cells had concentric receptive fields. They were similar to the uniform type, with the addition of a concentric inhibitory surround. Eight percent of the VLG cells had ambient receptive fields. These cells were characterized by an unusually regular maintained discharge which varied in rate in relation to the level of receptive-field illumination or of full-field ambient illumination. About 4% of the VLG cells were movement sensitive. They gave little or no response to stationary stimuli flashed on or off in the receptive field, and responded best to a contour moving across the receptive field in any direction. An additional 2.5% of the VLG cells were direction sensitive. Their response was dependent on the direction of stimulus movement through the receptive field. Sixteen percent of the VLG cells had indefinite receptive fields. They responded to whole-eye illumination or to localized visual-field stimulation; however, specific receptive-field properties could not be adequately defined. Approximately 23% of the VLG cells studied gave no convincing response to visual stimulation. 3. Responses of DLG cells agreed with those reported in previous studies. Almost all (97%) had concentric receptive fields, and a few (3%) had uniform receptive fields with no apparent antagonistic surround. None of the DLG cells had receptive fields like those in the other classes found for VLG cells. 4. The VLG cells tended to have large receptive fields; mean diameter was 10.6 degrees of visual arc. This was substantially larger than the diameter of receptive fields for DLG cells. In addition, VLG cells generally required larger stimuli than DLG cells to respond. There was no consistent relationship between receptive-field size and visual-field eccentricity for VLG cells, in contrast to the DLG. Most (57%) VLG cells were driven only by the contralateral eye, 30% were binocularly driven, and 13% were driven only by the ipsilateral eye. 5. A systematic visuotopic organization was present in the VLG. The lower visual field was represented anteriorly in the nucleus and the upper visual field posteriorly. The vertical meridian was represented along the dorsomedial border of the VLG where it abuts the DLG, and the temporal periphery was represented ventrolaterally. 6. Responses to electrical stimulation of the optic chiasm were studied for 55 VLG cells...

Effects of Vision Restoration Training on Early Visual Cortex in Patients With Cerebral Blindness Investigated With Functional Magnetic Resonance Imaging

2011 ◽  
Vol 105 (2) ◽  
pp. 872-882 ◽  
Author(s):  
M. Raemaekers ◽  
D. P. Bergsma ◽  
R. J. A. van Wezel ◽  
G. J. van der Wildt ◽  
A. V. van den Berg
Keyword(s):  
Magnetic Resonance Imaging ◽  
Visual Cortex ◽  
Magnetic Resonance ◽  
Visual Field ◽  
Receptive Field ◽  
Field Size ◽  
Functional Magnetic Resonance ◽  
Resonance Imaging ◽  
Retinotopic Maps ◽  
Early Visual Cortex

Cerebral blindness is a loss of vision as a result of postchiasmatic damage to the visual pathways. Parts of the lost visual field can be restored through training. However, the neuronal mechanisms through which training effects occur are still unclear. We therefore assessed training-induced changes in brain function in eight patients with cerebral blindness. Visual fields were measured with perimetry and retinotopic maps were acquired with functional magnetic resonance imaging (fMRI) before and after vision restoration training. We assessed differences in hemodynamic responses between sessions that represented changes in amplitudes of neural responses and changes in receptive field locations and sizes. Perimetry results showed highly varied visual field recovery with shifts of the central visual field border ranging between 1 and 7°. fMRI results showed that, although retinotopic maps were mostly stable over sessions, there was a small shift of receptive field locations toward a higher eccentricity after training in addition to increases in receptive field sizes. In patients with bilateral brain activation, these effects were stronger in the affected than in the intact hemisphere. Changes in receptive field size and location could account for limited visual field recovery (±1°), although it could not account for the large increases in visual field size that were observed in some patients. Furthermore, the retinotopic maps strongly matched perimetry measurements before training. These results are taken to indicate that local visual field enlargements are caused by receptive field changes in early visual cortex, whereas large-scale improvement cannot be explained by this mechanism.

Superimposed maps of the monocular visual fields in the caudolateral optic tectum in the frog, Rana pipiens

2005 ◽  
Vol 22 (1) ◽  
pp. 101-109 ◽  
Author(s):  
DANIEL E. WINKOWSKI ◽  
EDWARD R. GRUBERG
Keyword(s):  
Visual Field ◽  
Receptive Field ◽  
Optic Tectum ◽  
Visual Stimulation ◽  
Visual Fields ◽  
Nucleus Isthmi ◽  
Individual Layer ◽  
Functional Connection ◽  
Field Representation ◽  
Contralateral Eye

The superficial layers of the frog optic tectum receive a projection from the contralateral eye that forms a point-to-point map of the visual field. The monocular part of the visual field of the contralateral eye is represented in the caudolateral region of the tectum while the binocular part of the visual field is represented in the rostromedial tectum. Within the representation of the binocular field (rostromedial tectum), the maps of visual space from each eye are aligned. The tectal representation of the binocular visual field of the ipsilateral eye is mediated through a crossed projection from the midbrain nucleus isthmi. This isthmotectal projection also terminates in the caudolateral region of the optic tectum, yet there has been no indication that it forms a functional connection. By extracellular recording in intermediate layer 7 of the caudolateral tectum, we have discovered electrical activity driven by visual stimulation in the monocular visual field of the ipsilateral eye. The units driven from the ipsilateral eye burst upon initial presentation of the stimulus. At individual layer 7 recording sites in the caudolateral tectum, the multiunit receptive field evoked from the ipsilateral eye is located at the mirror image spatial location to the multiunit receptive field driven by the contralateral eye. Thus, as revealed electrophysiologically, there are superimposed topographic maps of the monocular visual fields in the caudolateral tectum. The ipsilateral eye monocular visual field representation can be abolished by electrolytic ablation of contralateral nucleus isthmi.

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