Optic Stimuli Research Articles

The effect of diabetic retinopathy on standing posture during optic flow stimulation

BackgroundDiabetic retinopathy is a principal cause of visual damage and blindness, in which laser treatment offers proven therapy. The progressive degeneration of the retina, secondary to diabetes, is believed to cause postural instability although this is not well documented. The aim of this research was to assess how optic flow stimuli contribute to the control of stance in people with impaired retinal functions. Research questionDoes the different retinal functionality correspond to different specific patterns of movements and muscles recruitment? MethodsPostural mechanisms and motor strategies were measured by testing subjects in quiet stance on a force platform with surface electromyography under different optic flow stimulations. Root mean square values of the center of pressure time-varying signals and normalized EMG values were used to evaluate the postural sway. ResultsPeople with diabetic retinopathy, and to a greater extent laser group, were more unstable than healthy subjects. The greater amplitude of the body sway observed in the retinopathy group, and especially in the laser group, could be an expression of the difficulty for this population in processing this kind of visual information. SignificanceThe increase in muscle activity indicates that there are musculoskeletal and postural changes in the lower limb musculature with increasing severity of diabetic retinopathy. An impaired retinal function might negatively affect postural control in a way that is dependent on the severity of retinal damage.

Multisensory Interactions in Virtual Reality: OpticFlowReduces Vestibular Sensitivity, butOnlyforCongruent Planes of Motion.

During exposure to Virtual Reality (VR) a sensory conflict may be present, whereby the visual system signals that the user is moving in a certain direction with a certain acceleration, while the vestibular system signals that the user is stationary. In order to reduce this conflict, the brain may down-weight vestibular signals, which may in turn affect vestibular contributions to self-motion perception. Here we investigated whether vestibular perceptual sensitivity is affected by VR exposure. Participants' ability to detect artificial vestibular inputs was measured during optic flow or random motion stimuli on a VR head-mounted display. Sensitivity to vestibular signals was significantly reduced when optic flow stimuli were presented, but importantly this was only the case when both visual and vestibular cues conveyed information on the same plane of self-motion. Our results suggest that the brain dynamically adjusts the weight given to incoming sensory cues for self-motion in VR; however this is dependent on the congruency of visual and vestibular cues.

A Causal Role of Area hMST for Self-Motion Perception in Humans.

Previous studies in the macaque monkey have provided clear causal evidence for an involvement of the medial-superior-temporal area (MST) in the perception of self-motion. These studies also revealed an overrepresentation of contraversive heading. Human imaging studies have identified a functional equivalent (hMST) of macaque area MST. Yet, causal evidence of hMST in heading perception is lacking. We employed neuronavigated transcranial magnetic stimulation (TMS) to test for such a causal relationship. We expected TMS over hMST to induce increased perceptual variance (i.e., impaired precision), while leaving mean heading perception (accuracy) unaffected. We presented 8 human participants with an optic flow stimulus simulating forward self-motion across a ground plane in one of 3 directions. Participants indicated perceived heading. In 57% of the trials, TMS pulses were applied, temporally centered on self-motion onset. TMS stimulation site was either right-hemisphere hMST, identified by a functional magnetic resonance imaging (fMRI) localizer, or a control-area, just outside the fMRI localizer activation. As predicted, TMS over area hMST, but not over the control-area, increased response variance of perceived heading as compared with noTMS stimulation trials. As hypothesized, this effect was strongest for contraversive self-motion. These data provide a first causal evidence for a critical role of hMST in visually guided navigation.

Limits of subjective and objective vection for ultra-high frame rate visual displays

Large-field optic flow generates the illusory percept of self-motion, termed ‘vection’. Smoother visual motion displays generate a more compelling subjective sense of vection and objective postural responses, as well as a greater sense of immersiveness for the user observing the visual display. Research suggests that the function linking frame rate and vection asymptotes at 60 frames per second (FPS), but previous studies have used only moderate frame rates that do not approach the limits of human perception. Here, we measure vection using subjective and objective (mean frequency and path length of postural centre-of-pressure (COP) excursions) responses following the presentation of high-contrast optic flow stimuli at slow and fast speeds and low and ultra-high frame rates. We achieve this using a novel rendering method implemented with a projector capable of sub-millisecond temporal resolution in order to simulate refresh rates ranging from very low (15 FPS) to ultra-high frame rates (480 FPS). The results suggest that subjective vection was experienced most strongly at 60 FPS. Below and above 60 FPS, subjective vection is generally weaker, shorter, and starts later, although this pattern varied slightly according to the speed of stimuli. For objective measures, while the frequency of postural sway was unaffected by frame rate, COP path length was greatest for 480 FPS stimuli. Together, our results support diminishing returns for vection above 60 FPS and provide insight into the use of high frame rate for enhancing the user experience in visual displays.

20 Optic Flow Stimuli Effects on Standing Balance in Young and Older People with Low and High Fall Risk

Abstract Introduction Optic flow stimuli can destabilise postural control, especially those with increased visual field dependence. This study aimed to examine the effects of optic flow stimuli on postural stability between: 1) younger and older adults; and 2) low-falls-risk and high-falls-risk older adults. Methods 76 participants were grouped into ‘young’ (20-40 years, n=25), and ‘old’ (≥65 years, n=51); the latter was further stratified into ‘old-LFR’ (low fall risk, n=27) and ‘old-HFR’ (high fall risk, n=24). Participants stood on a force platform in a dark room with motion capture markers on the head, torso and lower limb. Optic flow stimuli were projected on a large screen encompassing the field of view as moving white dots for 30 seconds in four different conditions: radial expansion, radial contraction, circular (roll vection) anticlockwise and circular clockwise. Postural control was calculated from center of pressure (COP) and lower limb joint and trunk angles; changes between baseline (static dots) and optic flow conditions were compared between groups. Results Optic flow stimuli led young and older participants to shift their COP in the expected direction for each stimulus condition (forward for expansion, backward for contraction, left for anticlockwise, right for clockwise). For radial expansion, significantly increased anteroposterior sway was found in old-LFR and old-HFR (p≤0.001) but not \young (p≥0.17). Similar results were seen for radial contraction. For circular clockwise, significantly increase mediolateral sway was found in old-HFR (p=0.002) but not young (p=0.912) or old-LFR (p=0.749). Results differed for circular anticlockwise, with greater changes seen in anteroposterior sway compared with mediolateral, particularly in old-HFR. No stimuli by group interaction effects were seen in body kinematics. Conclusions Optic flow stimuli have a more destabilising effect on balance in older than younger adults, particularly those at increased risk of falling.

Distinct forms of motion sensitivity impairments in Alzheimer\u2019s disease

Motion sensitivity impairment in Alzheimer’s disease (AD) is often characterized as elevated coherence threshold. An alternative way to measure motion sensitivity is the direction threshold, i.e., the minimal angle of motion direction that can be discriminated. So far, it is less clear whether and how the direction threshold is altered in AD. Here we asked a group of AD patients and two control groups of healthy participants (young and elderly adults) to judge their perceived heading direction based on a field of optic flow stimuli simulating a forward translation in the environment. We manipulated the heading direction and the coherence of the optic flow independently and measured the direction and coherence thresholds from each participant. We found that the direction threshold increased significantly in AD patients as compared to healthy controls, like the coherence threshold. Yet, the elevation in the direction threshold was less pronounced than the coherence threshold. Moreover, the magnitudes of the direction and coherence thresholds in AD patients were not correlated. Our results suggest that coherence and direction impairments are two distinct forms of motion deficits in AD patients which might be associated with independent neural mechanisms.

Shift in lateralization during illusory self‐motion: EEG responses to visual flicker at 10 Hz and frequency‐specific modulation by tACS

Self-motion perception is a key aspect of higher vestibular processing, suggested to rely upon hemispheric lateralization and alpha-band oscillations. The first aim of this study was to test for any lateralization in the EEG alpha band during the illusory sense of self-movement (vection) induced by large optic flow stimuli. Visual stimuli flickered at alpha frequency (approx. 10Hz) in order to produce steady state visually evoked potentials (SSVEPs), a robust EEG measure which allows probing the frequency-specific response of the cortex. The first main result was that differential lateralization of the alpha SSVEP response was found during vection compared with a matched random motion control condition, supporting the idea of lateralization of visual-vestibular function. Additionally, this effect was frequency-specific, not evident with lower frequency SSVEPs. The second aim of this study was to test for a causal role of the right hemisphere in producing this lateralization effect and to explore the possibility of selectively modulating the SSVEP response. Transcranial alternating current stimulation (tACS) was applied over the right hemisphere simultaneously with SSVEP recording, using a novel artefact removal strategy for combined tACS-EEG. The second main result was that tACS enhanced SSVEP amplitudes, and the effect of tACS was not confined to the right hemisphere. Subsequent control experiments showed the effect of tACS requires the flicker frequency and tACS frequency to be closely matched and tACS to be of sufficient intensity. Combined tACS-SSVEPs are a promising method for future investigation into the role of neural oscillations and for optimizing tACS.

Egomotion-related visual areas respond to active leg movements.

Monkey neurophysiology and human neuroimaging studies have demonstrated that passive viewing of optic flow stimuli activates a cortical network of temporal, parietal, insular, and cingulate visual motion regions. Here, we tested whether the human visual motion areas involved in processing optic flow signals simulating self-motion are also activated by active lower limb movements, and hence are likely involved in guiding human locomotion. To this aim, we used a combined approach of task-evoked activity and resting-state functional connectivity by fMRI. We localized a set of six egomotion-responsive visual areas (V6+, V3A, intraparietal motion/ventral intraparietal [IPSmot/VIP], cingulate sulcus visual area [CSv], posterior cingulate sulcus area [pCi], posterior insular cortex [PIC]) by using optic flow. We tested their response to a motor task implying long-range active leg movements. Results revealed that, among these visually defined areas, CSv, pCi, and PIC responded to leg movements (visuomotor areas), while V6+, V3A, and IPSmot/VIP did not (visual areas). Functional connectivity analysis showed that visuomotor areas are connected to the cingulate motor areas, the supplementary motor area, and notably to the medial portion of the somatosensory cortex, which represents legs and feet. We suggest that CSv, pCi, and PIC perform the visual analysis of egomotion-like signals to provide sensory information to the motor system with the aim of guiding locomotion.

Investigating the Crucial Role of Optic Flow in Postural Control: Central vs. Peripheral Visual Field

Optic flow stimuli are crucial for the control of stance in the upright position. The visual control of posture has recently received a lot of interest from several researchers. One of the most intriguing aspects is the contribution of the different parts of the visual field in the control of stance. Here we reviewed the results of several studies performed with different methodologies that tried to determine the effect of optic flow on postural control, by analyzing the role of the central and peripheral visual fields. Although the results were controversial, the majority of these studies agreed to assign the most important role in postural control to the peripheral retina. However, these studies were performed using different approaches and different definitions of the central and peripheral visual fields. The choice of the exact portion of the retina to be stimulated is crucial given that the stimulation of the central and the peripheral parts of the retina leads to the activation of different geniculo-cortical pathways and results in different cortical processing of information.

Study on predicted reaching position of moving body using video stimulus

Remote-controlled robots, which are expected to perform useful tasks, are required to move as intended by operators. The information used to perceive the remote environment including the robot is limited and the operators usually have to perceive or predict motions of the robot through visual information included in a video image. The limitation makes the remote operation difficult. In order to investigate influences of the limitation, we measured operator’s predictions about a position of a remote robot. We had operators do tasks where they navigate the robot to a target. The task is divided into two parts. In the first part, the operators are requested to start the robot to move and given video or non-video stimuli. In the latter part, they are requested to stop the robot at the target without any visual information and the reaching position at which the robot has stopped is measured. Consequently, it was shown that the video stimuli modulate the reaching position of the robot. This means the operators' predictions are modulated. This effect should be caused by the difference between the velocity of the robot on the video stimuli and that on the non-video stimuli. In addition, we investigated influences of optic flows related to robots' motions by a similar task to the prior one. We gave the operators optic flow stimuli during the latter part of the task, while the video stimuli are given during the first part. Then, it was shown that the optic flow stimuli have additional effect on modulating the predicted reaching position which is already modulated by the video stimuli in the first part. It seemed that optic flows related to a robot's motion navigated in a remote environment may modulate a prediction of its operator. We may use this effect well when we operate robots remotely.

Technologies of Nonlinear Stimulation: Role in the Treatment of Diseases of the Brain and the Potential Applications in Healthy Individuals

In 2015, the theory was proposed that links the development and maintenance of the typical in norm complex structure of neural networks and the activity of the brain with the complexity of visual and other sensory environmental signals that affect the person during the life. Simplification of the temporal structure of environmental cues is associated with abnormal development and aging of the central nervous system. As well, the use of fractal optic stimulation and complex aperiodic stimuli of other modalities may enhance the effectiveness of strategies for a recovery in the structure and function of the retina and brain, including neurodegenerative pathology, by reactivation of neuroplasticity. In the spectrum of nonlinear stimulating therapy techniques, different variants of mono- and multimodal fractal stimulation should be used, as well as their combinations with white noise, music therapy, cognitive, and physical training. We believe that using of non-linear stimulation technologies in a healthy person may be important in a variety of situations that lead to the simplification of the networks and dynamics of the activity of the brain. Application of physiologically adequate nonlinear stimuli is promising to slow and prevent age-related cognitive impairment in the elderly, in rehabilitation and recovery programs for healthy individuals of certain professions associated with physical or psychological stress, and athletes.

Modulation of complex spike activity differs between zebrin-positive and -negative Purkinje cells in the pigeon cerebellum.

The cerebellum is organized into parasagittal zones defined by its climbing and mossy fiber inputs, efferent projections, and Purkinje cell (PC) response properties. Additionally, parasagittal stripes can be visualized with molecular markers, such as heterogeneous expression of the isoenzyme zebrin II (ZII), where sagittal stripes of high ZII expression (ZII+) are interdigitated with stripes of low ZII expression (ZII-). In the pigeon vestibulocerebellum, a ZII+/- stripe pair represents a functional unit, insofar as both ZII+ and ZII- PCs within a stripe pair respond best to the same pattern of optic flow. In the present study, we attempted to determine whether there were any differences in the responses between ZII+ and ZII- PCs within a functional unit in response to optic flow stimuli. In pigeons of either sex, we recorded complex spike activity (CSA) from PCs in response to optic flow, marked recording sites with a fluorescent tracer, and determined the ZII identity of recorded PCs by immunohistochemistry. We found that CSA of ZII+ PCs showed a greater depth of modulation in response to the preferred optic flow pattern compared with ZII- PCs. We suggest that these differences in the depth of modulation to optic flow stimuli are due to differences in the connectivity of ZII+ and ZII- PCs within a functional unit. Specifically, ZII+ PCs project to areas of the vestibular nuclei that provide inhibitory feedback to the inferior olive, whereas ZII- PCs do not. NEW & NOTEWORTHY Although the cerebellum appears to be a uniform structure, Purkinje cells (PCs) are heterogeneous and can be categorized on the basis of the expression of molecular markers. These phenotypes are conserved across species, but the significance is undetermined. PCs in the vestibulocerebellum encode optic flow resulting from self-motion, and those that express the molecular marker zebrin II (ZII+) exhibit more sensitivity to optic flow than those that do not express zebrin II (ZII-).

Topographic Organization of Inferior Olive Projections to the Zebrin II Stripes in the Pigeon Cerebellar Uvula.

This study was aimed at mapping the organization of the projections from the inferior olive (IO) to the ventral uvula in pigeons. The uvula is part of the vestibulocerebellum (VbC), which is involved in the processing of optic flow resulting from self-motion. As in other areas of the cerebellum, the uvula is organized into sagittal zones, which is apparent with respect to afferent inputs, the projection patterns of Purkinje cell (PC) efferents, the response properties of PCs and the expression of molecular markers such as zebrin II (ZII). ZII is heterogeneously expressed such that there are sagittal stripes of PCs with high ZII expression (ZII+), alternating with sagittal stripes of PCs with little to no ZII expression (ZII−). We have previously demonstrated that a ZII+/− stripe pair in the uvula constitutes a functional unit, insofar as the complex spike activity (CSA) of all PCs within a ZII+/− stripe pair respond to the same type of optic flow stimuli. In the present study we sought to map the climbing fiber (CF) inputs from the IO to the ZII+ and ZII− stripes in the uvula. We injected fluorescent Cholera Toxin B (CTB) of different colors (red and green) into ZII+ and ZII− bands of functional stripe pair. Injections in the ZII+ and ZII− bands resulted in retrograde labeling of spatially separate, but adjacent regions in the IO. Thus, although a ZII+/− stripe pair represents a functional unit in the pigeon uvula, CF inputs to the ZII+ and ZII− stripes of a unit arise from separate regions of the IO.

Integration of visual and tactile information in reproduction of traveled distance.

In the natural world, self-motion always stimulates several different sensory modalities. Here we investigated the interplay between a visual optic flow stimulus simulating self-motion and a tactile stimulus (air flow resulting from self-motion) while human observers were engaged in a distance reproduction task. We found that adding congruent tactile information (i.e., speed of the air flow and speed of visual motion are directly proportional) to the visual information significantly improves the precision of the actively reproduced distances. This improvement, however, was smaller than predicted for an optimal integration of visual and tactile information. In contrast, incongruent tactile information (i.e., speed of the air flow and speed of visual motion are inversely proportional) did not improve subjects' precision indicating that incongruent tactile information and visual information were not integrated. One possible interpretation of the results is a link to properties of neurons in the ventral intraparietal area that have been shown to have spatially and action-congruent receptive fields for visual and tactile stimuli.NEW & NOTEWORTHY This study shows that tactile and visual information can be integrated to improve the estimates of the parameters of self-motion. This, however, happens only if the two sources of information are congruent-as they are in a natural environment. In contrast, an incongruent tactile stimulus is still used as a source of information about self-motion but it is not integrated with visual information.

Angle of gaze and optic flow direction modulate body sway

Optic flow is a crucial signal in maintaining postural stability. We sought to investigate whether the activity of postural muscles and body sway was modulated by eye position during the view of radial optic flow stimuli. We manipulated the spatial distribution of dot speed and the fixation point position to simulate specific heading directions combined with different gaze positions. The experiments were performed using stabilometry and surface electromyography (EMG) on 24 right-handed young, healthy volunteers. Center of pressure (COP) signals were analyzed considering antero-posterior and medio-lateral oscillation, COP speed, COP area, and the prevalent direction of oscillation of body sway. We found a significant main effect of body side in all COP parameters, with the right body side showing greater oscillations. The different combinations of optic flow and eye position evoked a non-uniform direction of oscillations in females. The EMG analysis showed a significant main effect for muscle and body side. The results showed that the eye position modulated body sway without changing the activity of principal leg postural muscles, suggesting that the extraretinal input regarding the eye position is a crucial signal that needs to be integrated with perceptual optic flow processing in order to control body sway.

Descending Neurons in Drosophila: Bridging the Gap between Vision and Action.

Each time we move our eyes or rotate our head, the whole visual field moves across our retinas. Such optic flow stimuli are contingent on the course of our movements and thus can be used to monitor self-movements. Many animals with image-forming eyes, from Drosophila to humans, seem to use optic

Differential processing of the direction and focus of expansion of optic flow stimuli in areas MST and V3A of the human visual cortex.

Human neuropsychological and neuroimaging studies have raised the possibility that different attributes of optic flow stimuli, namely radial direction and the position of the focus of expansion (FOE), are processed within separate cortical areas. In the human brain, visual areas V5/MT+ and V3A have been proposed as integral to the analysis of these different attributes of optic flow stimuli. To establish direct causal relationships between neural activity in human (h)V5/MT+ and V3A and the perception of radial motion direction and FOE position, we used transcranial magnetic stimulation (TMS) to disrupt cortical activity in these areas while participants performed behavioral tasks dependent on these different aspects of optic flow stimuli. The cortical regions of interest were identified in seven human participants using standard functional MRI retinotopic mapping techniques and functional localizers. TMS to area V3A was found to disrupt FOE positional judgments but not radial direction discrimination, whereas the application of TMS to an anterior subdivision of hV5/MT+, MST/TO-2 produced the reverse effects, disrupting radial direction discrimination but eliciting no effect on the FOE positional judgment task. This double dissociation demonstrates that FOE position and radial direction of optic flow stimuli are signaled independently by neural activity in areas hV5/MT+ and V3A.NEW & NOTEWORTHY Optic flow constitutes a biologically relevant visual cue as we move through any environment. With the use of neuroimaging and brain-stimulation techniques, this study demonstrates that separate human brain areas are involved in the analysis of the direction of radial motion and the focus of expansion in optic flow. This dissociation reveals the existence of separate processing pathways for the analysis of different attributes of optic flow that are important for the guidance of self-locomotion and object avoidance.

Convergence of visual and whisker responses in the primary somatosensory thalamus (ventral posterior medial region) of the mouse.

Key points Using in vivo electrophysiology, we find that a subset of whisker‐responsive neurons in the ventral posterior medial region (VPM) respond to visual stimuli.These light‐responsive neurons in the VPM are particularly sensitive to optic flow.Presentation of optic flow stimuli modulates the amplitude of concurrent whisker responses.Visual information reaches the VPM via a circuit encompassing the visual cortex.These data represent a new example of cross‐modal integration in the primary sensory thalamus. Sensory signals reach the cortex via sense‐specific thalamic nuclei. Here we report that neurons in the primary sensory thalamus of the mouse vibrissal system (the ventral posterior medial region; VPM) can be excited by visual as well as whisker stimuli. Using extracellular electrophysiological recordings from anaesthetized mice we first show that simple light steps can excite a subset of VPM neurons. We then test the ability of the VPM to respond to spatial patterns and show that many units are excited by visual motion in a direction‐selective manner. Coherent movement of multiple objects (an artificial recreation of ‘optic flow’ that would usually occur during head rotations or body movements) best engages this visual motion response. We next show that, when co‐applied with visual stimuli, the magnitude of responses to whisker deflections is highest in the presence of optic flow going in the opposite direction. Importantly, whisker response amplitude is also modulated by presentation of a movie recreating the mouse's visual experience during natural exploratory behaviour. We finally present functional and anatomical data indicating a functional connection (probably multisynaptic) from the primary visual cortex to VPM. These data provide a rare example of multisensory integration occurring at the level of the sensory thalamus, and provide evidence for dynamic regulation of whisker responses according to visual experience.

Grouping of optic flow stimuli during binocular rivalry is driven by monocular information

During binocular rivalry, perception alternates between two dissimilar images, presented dichoptically. Although binocular rivalry is thought to result from competition at a local level, neighboring image parts with similar features tend to be perceived together for longer durations than image parts with dissimilar features. This simultaneous dominance of two image parts is called grouping during rivalry. Previous studies have shown that this grouping depends on a shared eye-of-origin to a much larger extent than on image content, irrespective of the complexity of a static image. In the current study, we examine whether grouping of dynamic optic flow patterns is also primarily driven by monocular (eye-of-origin) information. In addition, we examine whether image parameters, such as optic flow direction, and partial versus full visibility of the optic flow pattern, affect grouping durations during rivalry. The results show that grouping of optic flow is, as is known for static images, primarily affected by its eye-of-origin. Furthermore, global motion can affect grouping durations, but only under specific conditions. Namely, only when the two full optic flow patterns were presented locally. These results suggest that grouping during rivalry is primarily driven by monocular information even for motion stimuli thought to rely on higher-level motion areas.

Visual Rehabilitation in Chronic Cerebral Blindness: A Randomized Controlled Crossover Study.

The treatment of patients suffering from cerebral blindness following stroke is a topic of much recent interest. Several types of treatment are under investigation, such as substitution with prisms and compensation training of saccades. A third approach, aimed at vision restitution is controversial, as a proper controlled study design is missing. In the current study, 27 chronic stroke patients with homonymous visual field defects were trained at home with a visual training device. We used a discrimination task for two types of stimuli: a static point stimulus and a new optic flow-discontinuity stimulus. Using a randomized controlled crossover design, each patient received two successive training rounds, one with high contrast stimuli in their affected hemifield (test) and one round with low-contrast stimuli in their intact hemifield (control). Goldmann and Humphrey perimetry were performed at the start of the study and following each training round. In addition, reading performance was measured. Goldmann perimetry revealed a statistically significant reduction of the visual field defect after the test training, but not after the control training or after no intervention. For both training rounds combined, Humphrey perimetry revealed that the effect of a directed training (sensitivity change in trained hemifield) exceeded that of an undirected training (sensitivity change in untrained hemifield). The interaction between trained and tested hemifield was just above the threshold of significance (p = 0.058). Interestingly, reduction of the field defect assessed by Goldmann perimetry increases with the difference between defect size as measured by Humphrey and Goldmann perimetry prior to training. Moreover, improvement of visual sensitivity measured by Humphrey perimetry increases with the fraction of non-responsive elements (i.e., more relative field loss) in Humphrey perimetry prior to training. Reading speed revealed a significant improvement after training. Our findings demonstrate that our training can result in reduction of the visual field. Improved reading performance after defect training further supports the significance of our training for improvement in daily life activities.