Binocular depth perception following early experience with interocular torsional disparity

1992 ◽  
Vol 9 (3-4) ◽  
pp. 303-312 ◽  
Author(s):  
Paul G. Shinkman ◽  
Brian Timney ◽  
Michael R. Isley
Keyword(s):  
Visual Acuity ◽  
Visual Cortex ◽  
Depth Perception ◽  
Visual Experience ◽  
Early Experience ◽  
Field Orientation ◽  
Visual Exposure ◽  
The Mean ◽  
The Relationship ◽  
Binocular Depth

AbstractThe relationship between the behavioral and physiological consequences of rearing with optically induced cyclotropia was assessed. Beginning at the age of 4 weeks, kittens wore goggles that rotated the visual field in opposite directions in each eye for several hours each day over a period of several weeks. The amounts of interocular rotation were 0 deg (control), 16 deg, and 32 deg. Subsequently, they were tested to determine their monocular and binocular depth thresholds and, in some cases, visual acuity. In several kittens recordings were also made from the visual cortex. Binocular performance of all kittens in the 0-deg condition and three out of six kittens in the 16-deg condition was comparable to, although slightly lower than, that of normally reared kittens. In contrast, none of the 32-deg kittens showed any evidence of the binocular superiority that would suggest the presence of stereopsis. Extracellular unit recordings from the visual cortex confirmed our earlier results with goggle-reared kittens. In 16-deg kittens, the distribution of the cells' preferred interocular disparities (IOD) in receptive-field orientation showed a compensating shift so that the mean matched the experienced rotational disparity. In the 32-deg kittens, binocularity was greatly disrupted and there was no compensatory shift in the IOD distribution. Two 32-deg kittens were afforded 3 years of subsequent normal visual experience. Both the behavioral and the physiological findings were unaffected by normal visual exposure in adulthood. Control measurements of acuity indicated that any deficits in depth perception were not due to reduced spatial-resolution abilities. The data indicate that the kitten visual system is able to maintain functional binocularity sufficient to subserve a moderate level of stereoacuity with interocular rotations of up to at least 16 deg.

scholarly journals Association of foveal avascular zone with the metamorphopsia in epiretinal membrane

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Hideki Shiihara ◽  
Hiroto Terasaki ◽  
Shozo Sonoda ◽  
Naoko Kakiuchi ◽  
Hidetaka Yamaji ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Superficial Layer ◽  
University Hospital ◽  
Foveal Avascular Zone ◽  
Service Unit ◽  
Corrected Visual Acuity ◽  
Avascular Zone ◽  
The Mean ◽  
The Relationship ◽  
Best Corrected Visual Acuity

Abstract This study was to investigate the relationship between the metamorphopsia and foveal avascular zone (FAZ) parameter in eyes with epiratinal membrane (ERM). We studied patients with an ERM visited retinal service unit at the Kagoshima University Hospital or Shirai Hospital. The best-corrected visual acuity (BCVA), and the degree of metamorphopsia by M -CHARTS™ were evaluated. The 3 × 3 mm optical coherence tomography angiography (OCTA) images of the superficial layer were obtained. Area (mm2), the circularity, eigen value were calculated using ImageJ software. The relationship between visual function, such as best corrected visual acuity (BCVA) and metamorphopsia, and FAZ parameters were studied by Pearson’s correlational coefficient. Fifty-four eyes of 51 patients (24 men and 27 women) with an ERM were studied. The mean age of the patients was 69.6 ± 8.20 years. The mean BCVA and metamorphopsia score was 0.31 ± 0.29 logMAR units and 0.49 ± 0.42. There was no significant relationship between BCVA and FAZ parameters. While, metamorphopsia score was significantly and negatively correlated with all of FAZ parameters (area R = − 0.491, P < 0.001; circularity R = − 0.385, P = 0.004; eigenvalue ratio R = − 0.341; P = 0.012). Multiple regression analysis showed the FAZ area was solely and significantly correlated with metamorphopsia score (β − 0.479, P < 0.001). The size but not the shape of the FAZ was significantly correlated with the degree of metamorphopsia suggesting that it could be an objective parameter of metamorphopsia in ERM patients.

scholarly journals Improvement of Visual Acuity in Partially and Fully Sighted Subjects as a Function of Practice, Feedback, and Instructional Techniques

1978 ◽  
Vol 46 (3) ◽  
pp. 815-822 ◽  
Author(s):  
Olga Overbury ◽  
Michael Bross
Keyword(s):  
Visual Acuity ◽  
Theoretical Model ◽  
Depth Perception ◽  
Optic Atrophy ◽  
Unexpected Finding ◽  
Testing Session ◽  
Vernier Acuity ◽  
The Third ◽  
Visual Improvement ◽  
Binocular Depth

Three experiments were conducted to examine improvement of partially (20/200 or 6/60) and normally (20/20 or 6/6) sighted adults. Measures of resolution and vernier acuity were examined in the first two experiments to determine whether practice, feedback, and instructions would have differential effects on the degree of visual improvement achieved in a 20-min. testing session. The results indicated extensive visual work to be the important factor in the improvement of impaired vision. The third experiment compared monocular and binocular depth perception of individuals with unilateral optic atrophy. The results yielded an unexpected finding where binocular depth perception was, in most cases, inferior to that of the strong eye alone. The first two experiments demonstrated the possibility of improving impaired visual functions and the third experiment suggests important implications for a theoretical model of depth perception with limited vision.

scholarly journals Closing the Critical Period Is Required for the Maturation of Binocular Integration in Mouse Primary Visual Cortex

2021 ◽  
Vol 15 ◽  
Author(s):  
Jiangping Chan ◽  
Xiangwen Hao ◽  
Qiong Liu ◽  
Jianhua Cang ◽  
Yu Gu
Keyword(s):  
Visual Cortex ◽  
Mouse Model ◽  
Primary Visual Cortex ◽  
Depth Perception ◽  
Critical Period ◽  
Visual Experience ◽  
Extracellular Recording ◽  
Molecular Assay ◽  
Binocular Matching

Binocular matching of orientation preference between the two eyes is a common form of binocular integration that is regarded as the basis for stereopsis. How critical period plasticity enables binocular matching under the guidance of normal visual experience has not been fully demonstrated. To investigate how critical period closure affects the binocular matching, a critical period prolonged mouse model was constructed through the administration of bumetanide, an NKCC1 transporter antagonist. Using acute in vivo extracellular recording and molecular assay, we revealed that binocular matching was transiently disrupted due to heightened plasticity after the normal critical period, together with an increase in the density of spines and synapses, and the upregulation of GluA1 expression. Diazepam (DZ)/[(R, S)-3-(2-carboxypiperazin-4-yl) propyl-1-phosphonic acid (CPP)] could reclose the extended critical period, and rescue the deficits in binocular matching. Furthermore, the extended critical period, alone, with normal visual experience is sufficient for the completion of binocular matching in amblyopic mice. Similarly, prolonging the critical period into adulthood by knocking out Nogo-66 receptor can prevent the normal maturation of binocular matching and depth perception. These results suggest that maintaining an optimal plasticity level during adolescence is most beneficial for the systemic maturation. Extending the critical period provides new clues for the maturation of binocular vision and may have critical implications for the treatment of amblyopia.

Functional and Morphologic Outcomes after Reoperation for Persistent Idiopathic Macular Hole

2016 ◽  
Vol 27 (2) ◽  
pp. 231-234 ◽  
Author(s):  
Akira Hagiwara ◽  
Takayuki Baba ◽  
Tomoaki Tatsumi ◽  
Eiju Sato ◽  
Toshiyuki Oshitari ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Macular Hole ◽  
Internal Limiting Membrane ◽  
Visual Recovery ◽  
Ilm Peeling ◽  
Tomographic Images ◽  
Initial Surgery ◽  
Second Surgery ◽  
The Mean ◽  
The Relationship

Purpose To determine the relationship between preoperative and postoperative characteristics and visual outcomes after successful surgery for unclosed macular hole (MH). Methods The medical charts of 166 eyes of 161 patients who underwent vitrectomy for a MH were reviewed. The MH was not closed in 9 eyes of 9 patients after the initial surgery. The second vitrectomy with additional internal limiting membrane (ILM) peeling and gas tamponade was performed. The preoperative and postoperative best-corrected visual acuity (BCVA), optical coherence tomographic images, MH size, duration of MH before the first operation, and area of ILM peeling were studied. Results The MH was closed in all eyes after the second surgery. The BCVA significantly improved from 0.77 to 0.25 logMAR units (20/118 to 20/36, p = 0.002). The postoperative subfoveal ellipsoid zone (EZ) was distinct and continuous in 3 eyes with good visual recovery. The final BCVA was not significantly correlated with the baseline characteristics and area of ILM peeling but was correlated with the postoperative status of the EZ. Conclusions All MHs were closed and the mean postoperative visual acuity was significantly improved. The reason for poor visual recovery was the reduced microstructural recovery after the second surgery.

scholarly journals TrkB Activation During a Critical Period Mimics the Protective Effects of Early Visual Experience on Perception and the Stability of Receptive Fields in Adult Superior Colliculus

2018 ◽  
Author(s):  
David B. Mudd ◽  
Timothy S. Balmer ◽  
So Yeon Kim ◽  
Noura Machhour ◽  
Sarah L. Pallas
Keyword(s):  
Visual Acuity ◽  
Visual Cortex ◽  
Receptive Field ◽  
Superior Colliculus ◽  
Spontaneous Activity ◽  
Signaling Pathway ◽  
Critical Period ◽  
Visual Experience ◽  
Receptive Fields ◽  
Trkb Receptors

AbstractDuring a critical period in development, spontaneous and evoked retinal activity shape visual pathways in an adaptive fashion. Interestingly, spontaneous activity is sufficient for spatial refinement of visual receptive fields in superior colliculus (SC) and visual cortex (V1), but early visual experience is necessary to maintain inhibitory synapses and stabilize RFs in adulthood (Carrasco et al. 2005, 2011; Carrasco & Pallas 2006; Balmer & Pallas 2015a). In visual cortex (V1), brain-derived neurotrophic factor (BDNF) and its high affinity receptor TrkB are important for development of visual acuity, inhibition, and regulation of the critical period for ocular dominance plasticity (Hanover et al., 1999; Huang et al., 1999; Gianfranceschi et al., 2003). To examine the generality of this signaling pathway for visual system plasticity, the present study examined the role of TrkB signaling during the critical period for RF refinement in SC. Activating TrkB receptors during the critical period (P33-40) in DR subjects produced normally refined RFs, and blocking TrkB receptors in light-exposed animals resulted in enlarged adult RFs like those in DR animals. We also report here that deprivation- or TrkB blockade-induced RF enlargement in adulthood impaired fear responses to looming overhead stimuli, and negatively impacted visual acuity. Thus, early TrkB activation is both necessary and sufficient to maintain visual RF refinement, robust looming responses, and visual acuity in adulthood. These findings suggest a common signaling pathway exists for the maturation of inhibition between V1 and SC.Significance StatementReceptive field refinement in superior colliculus (SC) differs from more commonly studied examples of critical period plasticity in visual pathways in that it does not require visual experience to occur; rather spontaneous activity is sufficient. Maintenance of refinement beyond puberty requires a brief, early exposure to light in order to stabilize the lateral inhibition that shapes receptive fields. We find that TrkB activation during a critical period can substitute for visual experience in maintaining receptive field refinement into adulthood, and that this maintenance is beneficial to visual survival behaviors. Thus, as in some other types of plasticity, TrkB signaling plays a crucial role in RF refinement.

Correlation between topographic progression of geographic atrophy and visual acuity changes

2020 ◽  
Author(s):  
Jong In You ◽  
Do Gyun Kim ◽  
Eung Suk Kim ◽  
Seung-Young Yu ◽  
Kiyoung Kim
Keyword(s):  
Visual Acuity ◽  
Geographic Atrophy ◽  
Circular Area ◽  
Automatic Software ◽  
The Mean ◽  
Concentric Circles ◽  
Foveal Center ◽  
The Relationship ◽  
Doughnut Shape

Abstract Background: To analyze topographic progression of geographic atrophy with different concentric circles centered on the fovea in correlation with decrease of visual acuity. Methods: We retrospectively analysed 36 eyes of 26 patients diagnosed with geographic atrophy and followed at least 1 year. 1mm circular area at the foveal center were defined as Zone 1, and doughnut shape areas from between 1 and 2 mm to between 5 and 6 mm were defined as Zone 2 to Zone 6. Then, changes of geographic atrophy area in each zone were measured with semi-automatic software. Correlation analysis and regression analysis were performed to determine the relationship between changes in visual acuity and atrophic area in each zone. Result: Mean age was 76.9 years and follow-up period were 3.38 years. The mean atrophic area increased from 8.09 to 16.34 mm2 and visual acuity decreased from 0.39 to 0.69 on logMAR. Mean change of total geographic atrophy area was not significantly correlated with visual acuity decrease. While geographic atrophy progression within Zone 1, Zone 2 and Zone 3 showed significant causal relationship with decrease of visual acuity (all p<0.05). Conclusion: In contrast to the total geographic atrophy area, progression of geographic atrophy in parafoveal area was significantly correlated with decrease of visual acuity.

scholarly journals Factors Influencing Contrast Sensitivity Function in Eyes with Mild Cataract

2021 ◽  
Vol 10 (7) ◽  
pp. 1506
Author(s):  
Kazutaka Kamiya ◽  
Fusako Fujimura ◽  
Takushi Kawamorita ◽  
Wakako Ando ◽  
Yoshihiko Iida ◽  
...  
Keyword(s):  
Visual Acuity ◽  
Contrast Sensitivity ◽  
Sensitivity Function ◽  
Contrast Sensitivity Function ◽  
Partial Regression Coefficient ◽  
Explanatory Variables ◽  
Uncorrected Visual Acuity ◽  
The Mean ◽  
The Relationship ◽  
Relevant Factors

This study was aimed to evaluate the relationship between the area under the log contrast sensitivity function (AULCSF) and several optical factors in eyes suffering mild cataract. We enrolled 71 eyes of 71 patients (mean age, 71.4 ± 10.7 (standard deviation) years) with cataract formation who were under surgical consultation. We determined the area under the log contrast sensitivity function (AULCSF) using a contrast sensitivity unit (VCTS-6500, Vistech). We utilized single and multiple regression analyses to investigate the relevant factors in such eyes. The mean AULSCF was 1.06 ± 0.16 (0.62 to 1.38). Explanatory variables relevant to the AULCSF were, in order of influence, logMAR best spectacle-corrected visual acuity (BSCVA) (p < 0.001, partial regression coefficient B = −0.372), and log(s) (p = 0.023, B = −0.032) (adjusted R2 = 0.402). We found no significant association with other variables such as age, gender, uncorrected visual acuity, nuclear sclerosis grade, or ocular HOAs. Eyes with better BSCVA and lower log(s) are more susceptible to show higher AULCSF, even in mild cataract subjects. It is indicated that both visual acuity and intraocular forward scattering play a role in the CS function in such eyes.

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