Search

• Combine binocular adding and subtracting channels with binocularity theory. • Dynamic weight is used for binocular fusion with the energy map. • Natural scene statistics feature is extracted to describe stereo image quality. • Achieve the balance between accuracy and timeliness. • The proposed algorithm has high performance on public datasets. Stereoscopic image quality evaluation is extremely significance as a performance evaluator of modern 3D display technology. Due to the complexity of human visual system (HVS) and the incomprehensive study of stereoscopic perception of human eyes, stereoscopic image quality assessment (SIQA) is still a challenging task. In this paper, combining binocular characteristics, we propose an efficient no-reference stereoscopic image quality assessment according to binocular adding and subtracting channels. Distinguished from other SIQA methods, which pay attention to complex binocular visual properties, the visual information which is closely bound up with image distortion from adding and subtracting channels to describe ocular dominance (alternate name binocularity) is proposed. To estimate the contribution of each channel in SIQA, a dynamic weighting system is proposed for binocular fusion according to local energy. Furthermore, quality awareness features based on multi-scale and multi-orientation are extracted to describe visual degradation. Comparing with existing methods, experimental results on public 3D image databases demonstrate the proposed framework achieves high consistent with the subjective quality scores. [ABSTRACT FROM AUTHOR]

The visual system is organized in a parallel and hierarchical architecture. However, the plasticity in hierarchical neural networks is controversial across different response features and at different levels. In this study, we recorded areas 17 and 21a, earlier and intermediate stages of the visual cortex in the cat, respectively, by single-unit recording and intrinsic-signal optical imaging. We found that ocular dominance (OD) plasticity evoked by monocular deprivation (MD) was stronger in area 21a than in area 17 in the critical period (CP), and this plasticity became weaker but still persisted in area 21a while it disappeared in area 17 beyond the CP. These results suggest a diversified functional plasticity along the visual information processing pathways in a hierarchical neural network. [ABSTRACT FROM AUTHOR]

The fact that seeing with two eyes is universal among vertebrates raises a problem that has long challenged vision scientists: how do animals with overlapping visual fields combine non-identical right and left eye images to achieve fusion and the perception of depth that follows? Most theories address this problem in terms of matching corresponding images on the right and left retinas. Here we suggest an alternative theory of binocular vision based on anatomical correspondence that circumvents the correspondence problem and provides a rationale for ocular dominance. [ABSTRACT FROM AUTHOR]

Purpose: To assess spectacle independence and patient satisfaction with pseudophakic mini-monovision in patients undergoing routine bilateral cataract surgery with implantation of an aspherical aberration-free intraocular lens (Akreos AO, Bausch and Lomb, USA). Methods: This study was a retrospective analysis that included 60 eyes of 30 consecutive patients between 2016 and 2018. The included patients had undergone sequential bilateral routine phacoemulsification after choosing the mini-monovision option. Test for ocular dominance was done using a sighting test. Emmetropia was aimed at in the dominant eye, while in the non-dominant eye the aim was myopia between −1 D and −1.5 D. The main outcome parameters were uncorrected distance visual acuity (UDVA), uncorrected near visual acuity (UNVA), and data reported from a questionnaire given to the patients at 3 months postoperative visit. Results: The study included 60 eyes of 30 consecutive patients. The mean binocular UDVA was 0.09 ± 0.07 logMAR. Twenty-eight patients (93%) had binocular UDVA of 0.2 logMAR or better. The mean binocular uncorrected intermediate distance visual acuity (at 65 cm) was 0.16 ± 0.12 logMAR. Twenty-six patients (87%) had binocular uncorrected intermediate distance visual acuity of 0.2 logMAR or better. The mean binocular UNVA (at 35 cm) was 0.30 ± 0.21 logMAR. Fourteen patients (47%) had binocular UNVA of 0.2 logMAR or better. The patients score in the questionnaire was significantly higher in far and intermediate vision than near vision (p = 0.022). The patients score was significantly higher in day vision than night vision (p = 0.031). The mean overall patient satisfaction was good (9.1 ± 1.54). Twenty-eight patients (93%) reported high spectacle independence for far vision (score 8, 9, or 10). Conclusion: Pseudophakic mini-monovision shows good results for spectacle independence and high patient satisfaction. It is a safe and inexpensive option after bilateral cataract surgery for correcting distance and intermediate vision. However, it might show lower results with near and night vision which is generally acceptable. Using aberration-free monofocal IOL allows for the residual normal positive corneal aberration that may augment the effect of monovision. [ABSTRACT FROM AUTHOR]

The competitive and inhibitory interactions between the two eyes' images are a pervasive aspect of binocular vision. Over the last decade, our understanding of the neural processes underpinning binocular rivalry (BR) and continuous flash suppression (CFS) has increased substantially, but we still have little understanding of the relationship between these two effects and their variation in the general population. Studies that pool data across individuals and eyes risk masking substantial variations in binocular vision that exist in the general population. To investigate this issue we compared the depth of inter-ocular suppression evoked by BR with that elicited by CFS, in a group (N = 25) of visually normal individuals. A noise pattern (either static for BR or dynamic for CFS) was presented to one eye and its suppressive influence on a probe grating presented simultaneously to the other eye was measured. We found substantial individual differences in the magnitude of suppression (a 10-fold variation in probe detection threshold) evoked by each task, but performance on BR was a significant predictor of performance on the CFS task. However many individuals showed marked asymmetries between the two eyes' ability to detect a suppressed target, that were not necessarily the same for the two tasks. There was a tendency for the magnitude of the asymmetry to increase as the refresh rate of the dynamic noise increased. The results suggest a common underlying mechanism is likely to be responsible, at least in part, for driving inter-ocular suppression under BR and CFS. The marked asymmetries in inter-ocular suppression at higher noise refresh rates, may be indicative of a difference in temporal processing between the eyes. [ABSTRACT FROM AUTHOR]

The ocular dominance shift observed after short-term monocular deprivation is a widely used measure of visual homeostatic plasticity in adult humans. Binocular rivalry and binocular combination techniques are used interchangeably to characterize homeostatic plasticity, sometimes leading to contradictory results. Here we directly compare the effect of short-term monocular deprivation on ocular dominance measured by either binocular rivalry or binocular combination and its dependence on the duration of deprivation (15 or 120 min) in the same group of participants. Our results show that both binocular rivalry and binocular combination provide reliable estimates of ocular dominance, which are strongly correlated across techniques both before and after deprivation. Moreover, while 15 min of monocular deprivation induce a larger shift of ocular dominance when measured using binocular combination compared to binocular rivalry, for both techniques, the shift in ocular dominance exhibits a strong dependence on the duration of monocular deprivation, with longer deprivation inducing a larger and longer-lasting shift in ocular dominance. Taken together, our results indicate that both binocular rivalry and binocular combination offer very consistent and reliable measurements of both ocular dominance and the effect short-term monocular deprivation. [ABSTRACT FROM AUTHOR]

A few hours of monocular deprivation with a diffuser eye patch temporarily strengthens the contribution of the deprived eye to binocular vision. This shift in favor of the deprived eye is characterized as a form of adult visual plasticity. Studies in animal and human models suggest that neuromodulators can enhance adult brain plasticity in general. Specifically, acetylcholine has been shown to improve certain aspects of visual function and plasticity in adulthood. We investigated whether a single administration of donepezil (a cholinesterase inhibitor) could further augment the temporary shift in perceptual eye dominance that occurs after 2 h of monocular patching. Twelve healthy adults completed two experimental sessions while taking either donepezil (5 mg, oral) or a placebo (lactose) pill. We measured perceptual eye dominance using a binocular phase combination task before and after 2 h of monocular deprivation with a diffuser eye patch. Participants in both groups demonstrated a significant shift in favor of the patched eye after monocular deprivation, however our results indicate that donepezil significantly reduces the magnitude and duration of the shift. We also investigated the possibility that donepezil reduces the amount of time needed to observe a shift in perceptual eye dominance relative to placebo control. For this experiment, seven subjects completed two sessions where we reduced the duration of deprivation to 1 h. Donepezil reduces the magnitude and duration of the patching-induced shift in perceptual eye dominance in this experiment as well. To verify whether the effects we observed using the binocular phase combination task were also observable in a different measure of sensory eye dominance, six subjects completed an identical experiment using a binocular rivalry task. These results also indicate that cholinergic enhancement impedes the shift that results from short-term deprivation. In summary, our study demonstrates that enhanced cholinergic potentiation interferes with the consolidation of the perceptual eye dominance plasticity induced by several hours of monocular deprivation.

Experience-dependent plasticity in the adult visual system is generally thought of as a cortical process. However, several recent studies have shown that perceptual learning or monocular deprivation can also induce plasticity in the adult dorsolateral geniculate nucleus (dLGN) of the thalamus. How plasticity in the thalamus and cortex interact in the adult visual system is ill-understood. To assess the influence of thalamic plasticity on plasticity in primary visual cortex (V1), we made use of our previous finding that during the critical period ocular dominance (OD) plasticity occurs in dLGN and requires thalamic synaptic inhibition. Using multielectrode recordings we find that this is also true in adult mice, and that in the absence of thalamic inhibition and plasticity, OD plasticity in adult V1 is absent. To study the influence of V1 on thalamic plasticity, we silenced V1 and show that during the critical period, but not in adulthood, the OD shift in dLGN is partially caused by feedback from V1. We conclude that during adulthood the thalamus plays an unexpectedly dominant role in experience-dependent plasticity in V1. Our findings highlight the importance of considering the thalamus as a potential source of plasticity in learning events that are typically thought of as cortical processes., Competing Interests: YQ, MA, SS, PN, Ld, JH, CL No competing interests declared, (© 2023, Qin et al.)

Purpose: In binocular vision, there is a dominant eye and a nondominant eye, a phenomenon termed ocular dominance. This study determined the differences and associations of the ocular blood flow parameters between dominant and nondominant eyes in healthy Japanese subjects., Methods: This cross-sectional study included 128 eyes of 64 subjects (13 male and 51 female) aged ≥ 20 years. The ocular blood flow parameters were assessed using laser speckle flowgraphy (LSFG), and software was used to calculate the mean blur rate (MBR), which reflects the blood flow velocity., Results: There were no significant differences in axial length (AL), spherical equivalent (SE), intraocular pressure (IOP), uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), or ocular blood flow parameters between the dominant and nondominant eyes. The ocular blood flow parameters of the dominant eye were significantly and positively correlated with those of the nondominant eye (all P < 0.001)., Conclusions: No significant differences in ocular blood flow parameters exist between the dominant and nondominant eyes in healthy subjects. The ocular blood flow parameters in the dominant eye are associated with those in the nondominant eye., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2023, Nakaniida et al.)

The capacity for neural plasticity in the mammalian central visual system adheres to a temporal profile in which plasticity peaks early in postnatal development and then declines to reach enduring negligible levels. Early studies to delineate the critical period in cats employed a fixed duration of monocular deprivation to measure the extent of ocular dominance changes induced at different ages. The largest deprivation effects were observed at about 4 weeks postnatal, with a steady decline in plasticity thereafter so that by about 16 weeks only small changes were measured. The capacity for plasticity is regulated by a changing landscape of molecules in the visual system across the lifespan. Studies in rodents and cats have demonstrated that the critical period can be altered by environmental or pharmacological manipulations that enhance plasticity at ages when it would normally be low. Immersion in complete darkness for long durations (dark rearing) has long been known to alter plasticity capacity by modifying plasticity-related molecules and slowing progress of the critical period. In this study, we investigated the possibility that brief darkness (dark exposure) imposed just prior to the critical period peak can enhance the level of plasticity beyond that observed naturally. We examined the level of plasticity by measuring two sensitive markers of monocular deprivation, namely, soma size of neurons and neurofilament labeling within the dorsal lateral geniculate nucleus. Significantly larger modification of soma size, but not neurofilament labeling, was observed at the critical period peak when dark exposure preceded monocular deprivation. This indicated that the natural plasticity ceiling is modifiable and also that brief darkness does not simply slow progress of the critical period. As an antecedent to traditional amblyopia treatment, darkness may increase treatment efficacy even at ages when plasticity is at its highest. [ABSTRACT FROM AUTHOR]

Short-term monocular deprivation strengthens the contribution of the deprived eye to binocular vision. This change has been observed in adults with normal vision or amblyopia. The change in ocular dominance is transient and recovers over approximately one hour. This shift has been measured with various visual tasks, including binocular rivalry and binocular combination. We investigated whether the ocular dominance shift could be accumulated across multiple periods of monocular deprivation over consecutive days. We used a binocular phase combination task to measure the shift in eye dominance. We patched the dominant eye of ten adults with normal vision for two hours across five consecutive days. Our results show no cumulative effect after repeated sessions of short-term monocular deprivation. [ABSTRACT FROM AUTHOR]

Binocular rivalry (BR) is a dynamic visual illusion that provides insight into the cortical mechanisms of visual awareness, stimulus selection, and object identification. When dissimilar binocular images cannot be fused, perception switches every few seconds between the left and right eye images. The speed at which individuals switch between alternatives is a stable, partially heritable trait. In order to isolate the monocular and binocular processes that determine the speed of rivalry, we presented stimuli tagged with a different flicker frequency in each eye and applied stimulus-phase locked MEG source imaging. We hypothesized that the strength of the evoked fundamental or intermodulation frequencies would vary when comparing Fast and Slow Switchers. Ten subjects reported perceptual alternations, with mean dominance durations between 1.2–4.0 sec. During BR, event-related monocular input in V1, and broadly in higher-tier ventral temporal cortex, waxed and waned with the periods of left or right eye dominance/suppression. In addition, we show that Slow Switchers produce greater evoked intermodulation frequency responses in a cortical network composed of V1, lateral occipital, posterior STS, retrosplenial & superior parietal cortices. Importantly, these dominance durations were not predictable from the brain responses to either of the fundamental tagging frequencies in isolation, nor from any responses to a pattern rivalry control condition, or a non-rivalrous control. The novel cortical network isolated, which overlaps with the default-mode network, may contain neurons that compute the level of endogenous monocular difference, and monitor accumulation of this conflict over extended periods of time. These findings are the first to relate the speed of rivalry across observers to the ‘efficient coding’ theory of computing binocular differences that may apply to binocular vision generally. [ABSTRACT FROM AUTHOR]

Objectives To study, whether there are associations between chewing side preference and other lateralities, whether there is a genetic origin for preferred chewing side (PCS), relations to sex, birth order and orthodontic treatment. Materials and Methods The study included 113 twin pairs, 57 pairs monozygotic, 47 pairs same sex dizygotic and 9 pairs of opposite sex. The lateralities of preferred chewing side, footedness and eyedness were assessed by functional tests and handedness was checked by asking. Results Right-handed, -footed and -eyed as separated groups, and true-right sided (combined), were evenly distributed by preferred chewing side. By contrast, left-handed, -footed, -eyed and non-right sided used more left or both sides when chewing. Birth order affected preferred chewing side among monozygotic: the first-born twin was more likely to have the preferred chewing side on the non-right, whereas second-born twins used right side. Gender, zygosity and orthodontic treatment were not statistically significant factors. Limitations Examination of chewing sidedness could have been done in several different ways to provide a definite result. Sample size of opposite sex twins was very small. Conclusions Preferred chewing side generally seemed to follow the side where other lateralities occur; however, monozygotic twins seemed to be more receptive to it. True-right sided were more evenly distributed than non-right sided by the preferred chewing side. [ABSTRACT FROM AUTHOR]

It is well established across many species that neurons in the primary visual cortex (V1) display preference for visual input from one eye or the other, which is termed ocular dominance (OD). In rodents, V1 neurons exhibit a strong bias toward the contralateral eye. Molecular mechanisms of how OD is established and later maintained by plastic changes are largely unknown. Here we report a novel role of an activity-dependent immediate early gene Homer1a (H1a) in these processes. Using both sexes of H1a knock-out (KO) mice, we found that there is basal reduction in the OD index of V1 neurons measured using intrinsic signal imaging. This was because of a reduction in the strength of inputs from the contralateral eye, which is normally dominant in mice. The abnormal basal OD index was not dependent on visual experience and is driven by postnatal expression of H1a. Despite this, H1a KOs still exhibited normal shifts in OD index following a short-term (2-3 d) monocular deprivation (MD) of the contralateral eye with lid suture. However, unlike wild-type counterparts, H1a KOs continued to shift OD index with a longer duration (5- 6 d) of MD. The same phenotype was recapitulated in a mouse model that has reduced Homerl binding to metabotropic glutamate receptor 5 (mGluR5). Our results suggest a novel role of H1a and its interaction with mGluR5 in strengthening contralateral eye inputs during postnatal development to establish normal contralateral bias in mouse V1 without much impact on OD shift with brief MD. [ABSTRACT FROM AUTHOR]

Animals, from invertebrates to humans, stabilize the panoramic optic flow through compensatory movements of the eyes, the head or the whole body, a behavior known as optomotor response (OR). The same optic flow moved clockwise or anticlockwise elicits equivalent compensatory right or left turning movements, respectively. However, if stimulated monocularly, many animals show a unique effective direction of motion, i.e., a unidirectional OR. This phenomenon has been reported in various species from mammals to birds, reptiles, and amphibious, but among invertebrates, it has only been tested in flies, where the directional sensitivity is opposite to that found in vertebrates. Although OR has been extensively investigated in crabs, directional sensitivity has never been analyzed. Here, we present results of behavioral experiments aimed at exploring the directional sensitivity of the OR in two crab species belonging to different families: the varunid mud crab Neohelice granulata and the ocypode fiddler crab Uca uruguayensis. By using different conditions of visual perception (binocular, left or right monocular) and direction of flow field motion (clockwise, anticlockwise), we found in both species that in monocular conditions, OR is effectively displayed only with progressive (front-to-back) motion stimulation. Binocularly elicited responses were directional insensitive and significantly weaker than monocular responses. These results are coincident with those described in flies and suggest a commonality in the circuit underlying this behavior among arthropods. Additionally, we found the existence of a remarkable eye dominance for the OR, which is associated to the size of the larger claw. This is more evident in the fiddler crab where the difference between the two claws is huge. [ABSTRACT FROM AUTHOR]

The maturation of GABAergic inhibitory circuits is necessary for the onset of the critical period for ocular dominance plasticity (ODP) in the postnatal visual cortex (Hensch, 2005; Espinosa and Stryker, 2012). When it is deficient, the critical period does not start. When inhibitory maturation or signaling is precocious, it induces a precocious critical period. Heterochronic transplantation of GABAergic interneuron precursors derived from the medial ganglionic eminence (MGE) can induce a second period of functional plasticity in the visual cortex (Southwell et al., 2010). Although the timing of MGE transplantation-induced plasticity is dictated by the maturation of the transplanted cells, its mechanisms remain largely unknown. Here, we sought to test the effect of blocking vesicular GABA loading and subsequent release by transplanted interneurons on the ability to migrate, integrate, and induce plasticity in the host circuitry. We show that MGE cells taken from male and female donors that lack vesicular GABA transporter (Vgat) expression disperse and differentiate into somatostatin- and parvalbumin-expressing interneurons upon heterochronic transplantation in the postnatal mouse cortex. Although transplanted Vgat mutant interneurons come to express mature interneuron markers and display electrophysiological properties similar to those of control cells, their morphology is significantly more complex. Significantly, Vgat mutant MGE transplants fail to induce ODP, demonstrating the pivotal role of vesicular GABAergic transmission for MGE transplantation-induced plasticity in the postnatal mouse visual cortex. [ABSTRACT FROM AUTHOR]

How to precisely quantify the binocular eye balance (i.e., the contribution that each eye makes to the binocular percept) across a range of spatial frequencies using a binocular combination task, is an important issue in both clinical and basic research. In this study, we aimed to compare the precision of a binocular orientation combination paradigm with that of the standard binocular phase combination paradigm in measuring the binocular eye balance at low to high spatial frequencies. Nine normal adults (average age: 24.6 ± 2.0 years old) participated. Subjects viewed an LED screen dichoptically with polarized glasses in a dark room. The method of constant stimuli was used to quantitatively assess the point of subjective equality (PSE), i.e., the interocular contrast ratio when two eyes are balanced in binocular combination, for stimulus spatial frequencies from 0.5 to 8 cycles/degree. Precision was quantified by the variance [i.e., standard error (SE), obtained from 100 bootstrap estimates] associated to the PSE. Using stimuli whose interocular phase difference at the edge of the gratings was matched at 45°, we found that the orientation paradigm provides more precision than the standard binocular phase combination paradigm, especially at high frequencies (Experiment 1). Such differences remained when using stimuli that had three times larger interocular phase difference (Experiment 2) or displayed at four times higher stimuli resolution (Experiment 3). Our results indicate that a binocular combination tasked based on orientation rather than phase, provides a more precise estimate of binocular eye balance in human adults at high spatial frequencies, thus allowing a binocular balance to be assessed within the spatial region where amblyopes are most defective (i.e., high spatial frequencies). [ABSTRACT FROM AUTHOR]

Ocular dominance plasticity is a well-documented phenomenon allowing us to study properties of cortical maturation. Understanding this maturation might be an important step towards unravelling how cortical circuits function. However, it is still not fully understood which mechanisms are responsible for the opening and closing of the critical period for ocular dominance and how changes in cortical responsiveness arise after visual deprivation. In this article, we present a theory of ocular dominance plasticity. Following recent experimental work, we propose a framework where a reduction in inhibition is necessary for ocular dominance plasticity in both juvenile and adult animals. In this framework, two ingredients are crucial to observe ocular dominance shifts: a sufficient level of inhibition as well as excitatory-to-inhibitory synaptic plasticity. In our model, the former is responsible for the opening of the critical period, while the latter limits the plasticity in adult animals. Finally, we also provide a possible explanation for the variability in ocular dominance shifts observed in individual neurons and for the counter-intuitive shifts towards the closed eye. [ABSTRACT FROM AUTHOR]

There is convincing evidence that the deprivation of one sense can lead to adaptive neuronal changes in spared primary sensory cortices. However, the repercussions of late-onset sensory deprivations on functionality of the remaining sensory cortices are poorly understood. Using repeated intrinsic signal imaging we investigated the effects of whisker or auditory deprivation (WD or AD, respectively) on responsiveness of the binocular primary visual cortex (V1) in fully adult mice. The binocular zone of mice is innervated by both eyes, with the contralateral eye always dominating V1 input over ipsilateral eye input, the normal ocular dominance (OD) ratio. Strikingly, we found that 3 days of WD or AD induced a transient shift of OD, which was mediated by a potentiation of V1 input through the ipsilateral eye. This cross-modal effect was accompanied by strengthening of layer 4 synapses in V1, required visual experience through the ipsilateral eye and was mediated by an increase of the excitation/inhibition ratio in V1. Finally, we demonstrate that both WD and AD induced a long-lasting improvement of visual performance. Our data provide evidence that the deprivation of a non-visual sensory modality cross-modally induces experience dependent V1 plasticity and improves visual behavior, even in adult mice. [ABSTRACT FROM AUTHOR]

Objectives: The aim of this study was to investigate whether short‐term inverse occlusion, combined with moderate physical exercise, could promote the recovery of visual acuity and stereopsis in a group of adult anisometropic amblyopes. Methods: Ten adult anisometropic patients underwent six brief (2 h) training sessions over a period of 4 weeks. Each training session consisted in the occlusion of the amblyopic eye combined with physical exercise (intermittent cycling on a stationary bike). Visual acuity (measured with ETDRS charts), stereoacuity (measured with the TNO test), and sensory eye dominance (measured with binocular rivalry) were tested before and after each training session, as well as in follow‐up visits performed 1 month, 3 months, and 1 year after the end of the training. Results: After six brief (2 h) training sessions, visual acuity improved in all 10 patients (0.15 ± 0.02 LogMar), and six of them also recovered stereopsis. The improvement was preserved for up to 1 year after training. A pilot experiment suggested that physical activity might play an important role for the recovery of visual acuity and stereopsis. Conclusions: Our results suggest a noninvasive training strategy for adult human amblyopia based on an inverse‐occlusion procedure combined with physical exercise. [ABSTRACT FROM AUTHOR]

A few hours of monocular deprivation with a diffuser eye patch temporarily strengthens the contribution of the deprived eye to binocular vision. This shift in favor of the deprived eye is characterized as a form of adult visual plasticity. Studies in animal and human models suggest that neuromodulators can enhance adult brain plasticity in general. Specifically, acetylcholine has been shown to improve certain aspects of visual function and plasticity in adulthood. We investigated whether a single administration of donepezil (a cholinesterase inhibitor) could further augment the temporary shift in perceptual eye dominance that occurs after 2 h of monocular patching. Twelve healthy adults completed two experimental sessions while taking either donepezil (5 mg, oral) or a placebo (lactose) pill. We measured perceptual eye dominance using a binocular phase combination task before and after 2 h of monocular deprivation with a diffuser eye patch. Participants in both groups demonstrated a significant shift in favor of the patched eye after monocular deprivation, however our results indicate that donepezil significantly reduces the magnitude and duration of the shift. We also investigated the possibility that donepezil reduces the amount of time needed to observe a shift in perceptual eye dominance relative to placebo control. For this experiment, seven subjects completed two sessions where we reduced the duration of deprivation to 1 h. Donepezil reduces the magnitude and duration of the patching-induced shift in perceptual eye dominance in this experiment as well. To verify whether the effects we observed using the binocular phase combination task were also observable in a different measure of sensory eye dominance, six subjects completed an identical experiment using a binocular rivalry task. These results also indicate that cholinergic enhancement impedes the shift that results from short-term deprivation. In summary, our study demonstrates that enhanced cholinergic potentiation interferes with the consolidation of the perceptual eye dominance plasticity induced by several hours of monocular deprivation. [ABSTRACT FROM AUTHOR]

Highlights • Whisker deprivation restores "adult-like" ocular dominance plasticity in the primary visual cortex of fully adult mice. • This is accompanied with reduced GABA levels in the visual cortex. • However, re-increasing GABA levels with diazepam does not abolish reactivated ocular dominance plasticity. • Strikingly, this treatment changes the signature of visual cortex plasticity from "adult-like" to "juvenile-like". • This cross-modally restored "juvenile-like" plasticity is NMDA receptor dependent. Abstract In juvenile and young adult mice monocular deprivation (MD) shifts the ocular dominance (OD) of binocular neurons in the primary visual cortex (V1) away from the deprived eye. However, OD plasticity is completely absent in mice older than 110 days, but can be reactivated by treatments which decrease GABA levels in V1. Typically, these OD shifts can be prevented by increasing GABAergic transmission with diazepam. We could recently demonstrate that both bilateral whisker and auditory deprivation (WD, AD), can also restore OD plasticity in mice older than 110 days, since MD for 7 days in WD mice caused a potentiation of V1 input through the ipsilateral (open) eye, the characteristic feature of OD plasticity of "young adult" mice. Here we examined whether WD for 7 days also decreases GABA levels. For this, we performed post mortem HPLC analysis of V1 tissue. Indeed, we found that WD significantly decreased GABA levels in V1. Surprisingly, enhancing GABAergic inhibition by diazepam did not abolish OD shifts in WD mice, as revealed by repeated intrinsic signal imaging. On the contrary, this treatment led to a depression of V1 input through the previously closed contralateral eye, the characteristic signature of OD plasticity in juvenile mice during the critical period. Interestingly, the same result was obtained after AD. Taken together, these results suggest that cross-modally restored OD plasticity does not only depend on reduction of GABA levels in V1, but also requires other, so far unknown mechanisms. [ABSTRACT FROM AUTHOR]

The acceleration of the evolution of economic culture through scientific development affords the opportunity to re-examine cross-domain dialogue and research in Buddhism and other disciplines. The concepts of threefold training in Buddhism (i.e. precepts, samadhi, and wisdom) were used as data items to generate data values and thereby convey the semantic nature of these terms. A systems analysis approach that can adequately incorporate hermeneutics into management science was employed to present the research topic. This study illustrates the relationship between a management activity (i.e. its effectiveness and efficiency, and the mechanism used) and a Buddhist activity (i.e. threefold training). This relationship was used to establish a body- and mind-transcending system comprising two subsystems: a service subsystem that adopts the perspective of management science by emphasising the 'way of things' and a submission subsystem that adopts a Buddhist perspective by stressing the 'way of people'. The main finding of this study is that the two subsystems are characterised by identical Buddhist concepts. [ABSTRACT FROM AUTHOR]

Neurons in the primate primary visual cortex (V1) combine left- and right-eye information to form a binocular output. Controversy surrounds whether ocular dominance, the preference of these neurons for one eye over the other, is functionally relevant. Here, we demonstrate that ocular dominance impacts gain control during binocular combination. We recorded V1 spiking activity while monkeys passively viewed grating stimuli. Gratings were either presented to one eye (monocular), both eyes with the same contrasts (binocular balanced), or both eyes with different contrasts (binocular imbalanced). We found that contrast placed in a neuron's dominant eye was weighted more strongly than contrast placed in a neuron's non-dominant eye. This asymmetry covaried with neurons' ocular dominance. We then tested whether accounting for ocular dominance within divisive normalization improves the fit to neural data. We found that ocular dominance significantly improved model performance, with interocular normalization providing the best fits. These findings suggest that V1 ocular dominance is relevant for response normalization during binocular stimulation. [Display omitted] • V1 dichoptic responses are weighted more by contrast placed in the dominant eye • Asymmetry of V1 dichoptic responses correlates with neurons' ocular dominance • Ocular dominance can be parameterized within a divisive normalization framework • Interocular normalization weighted by OD best explains V1 dichoptic responses Some cortical neurons exhibit a response preference for one eye or the other. Mitchell et al. report that this ocular dominance (OD) indicates the level of gain control exerted on the non-preferred eye during binocular contrast combination. Incorporating OD into models of binocular contrast combination improves model performance. [ABSTRACT FROM AUTHOR]

In this paper, we present a multi-layer, activity-dependent model for the joint development of ocular dominance (OD) columns and cytochrome oxidase (CO) blobs in primate V1. For simplicity, we focus on layers 4C and 2/3 with both layers receiving direct thalamic inputs and layer 4C sending vertical projections to layer 2/3. Both the thalamic and the vertical connections are taken to be modifiable by activity. Using a correlation-based Hebbian learning rule with subtractive normalization, we show how the formation of an OD map in layer 4C is inherited by layer 2/3 via the vertical projections. Competition between these feedforward projections and the direct thalamic input to layer 2/3 then results in the formation of CO blobs superimposed upon the ocular dominance map. The spacing of the OD columns is determined by the spatial profile of the intralaminar connections within layer 4, while the spacing of CO blobs depends both on the width of the OD columns inherited from layer 4 and the spatial distribution of intralaminar connections within the superficial layer. The resulting CO blob distribution is shown to be consistent with experimental data. In addition, we numerically simulate monocular deprivation and find that while the CO blob distribution is unaltered, the OD pattern undergoes modification. The OD stripes of the deprived eye narrow, whereas the OD stripes for the remaining open eye widen. • Hebbian learning model on multiple cortical laminae during development of V1. • Turing mechanism within layer 4C yields the OD pattern, then inherited in layer 2/3 • Alignment of CO blobs in center of OD stripes determined by leading order behavior. • Another Turing mechanism in layer 2/3 results in formation of CO blobs. • Spacing of CO blob distribution set by shape of lateral circuitry within layer 2/3. distribution influence by lateral circuitry of layer 2/3. [ABSTRACT FROM AUTHOR]

The integration of hypotheses from Eye-Movement Desensitization and Reprocessing (EMDR) and Saccade Induced Retrieval Enhancement (SIRE), both of which have been met with considerable skepticism, may lead to significant gains in both domains. Cognitive accounts of EMDR, the orienting response (OR) and working memory (WM) hypotheses, and of SIRE, the interhemispheric interaction (IHI) and the top-down attentional control (TDAC) hypotheses, are discussed. The accounts show several blind spots and frictions, for instance, on re-imagining during EMs, on hemispheric lateralization, and on emotional influences of eye movements. The failure to consider these factors across and within domains may well explain the many disparate findings. This perspective aims to remove the artificial separation and seeks a theoretical integration of the domains. It combines elements of OR and TDAC into a new dopaminergic regulation hypothesis while replacing affective (i.e., positive vs. negative) by motivational mechanisms (i.e., fostering approach and recoding). EMs are posited to result in a short-latency, targeted release of dopamine, which is the central neuromodulator in approach tendencies. According to this hypothesis, the largest effects are obtained in individuals with collateralized eye dominance and dopamine dominance. Concrete suggestions are made to improve research conditions and therapeutic efficacy. • The perspective synthesizes hypotheses from EMDR and SIRE into the dopaminergic regulation hypothesis. • Eye movements elicit a dopamine signal from Superior Colliculus to Substantia Nigra. • The signal causes approach to, enhancement, and regulation of negative memories. • Eye movements are most effective with collateralized eye and dopamine dominance. • Optimizations for EMDR and SIRE are suggested. [ABSTRACT FROM AUTHOR]

• Red and near-infrared intrinsic signal optical imaging show similar contralateral ocular dominance. • Near-infrared rather than red light reveals the early-stage ocular dominance shift in adult mice, but both similarly detect the saturated ocular dominance shift. • Neurons in deep layers of the visual cortex shift ocular dominance earlier than neurons in superficial layers during deprivation. • The early phase of adult ocular dominance plasticity depends on the activation of N-methyl-D-aspartic acid (NMDA) receptors. Long term monocular deprivation is considered to be necessary for the induction of significant ocular dominance plasticity in the adult visual cortex. In this study, we subjected adult mice to monocular deprivation for various durations and screened for changes in ocular dominance using dual-wavelength intrinsic signal optical imaging. We found that short-term deprivation was sufficient to cause a shift in ocular dominance and that these early-stage changes were detected only by near-infrared illumination. In addition, single-unit recordings showed that these early-stage changes primarily occurred in deep cortical layers. This early-stage ocular dominance shift was abolished by the blockade of NMDA receptors. In summary, our findings reveal an early phase of adult ocular dominance plasticity and provide the dynamics of adult plasticity. [ABSTRACT FROM AUTHOR]

Pinakin Gunvant Davey, Silverio D Alvarez, Jessica Y Lee College of Optometry, Western University of Health Sciences, Pomona, CA, USA Purpose: To evaluate short-term repeatability, intereye correlation, and effect of ocular dominance on macular pigment optical density (MPOD) measurements obtained using the QuantifEye Heterochromatic Flicker Photometer.Patients and methods: A total of 72 study participants were enrolled in this prospective, cross-sectional study. Participants underwent a comprehensive ocular evaluation, including visual acuity, evaluation of ocular dominance, slit lamp examination, intraocular pressure measurement, and optic nerve head and macula analysis using optical coherence tomography and fundus photography. All study participants after initial training underwent MPOD measurement twice in both eyes in a randomized sequence. The repeatability was tested using Altman and Bland plots for first measurements with the second measurements for right eye and left eye and additionally by grouping eyes as a function of ocular dominance. The Pearson correlation coefficient was performed to assess the intereye correlation of MPOD values.Results: The mean age of study participants was 35.5 years (range 22–68 years). The mean MPOD measurements for OD (right eye) and OS (left eye) were 0.47 and 0.48, respectively, which followed a normal distribution (Shapiro–Wilk test, P=0.6 and 0.2). The 95% limits of agreement of Altman and Bland plots for the first and second measurements were -0.12 to +0.11 and -0.13 to +0.12 for OD and OS, respectively. The correlation coefficient of mean MPOD measurements of OD and OS was r statistic =0.94 (Pearson correlation coefficient P