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The aim of the present research is to test whether resilience in a motor task enhances or diminishes when encountering stressors. We conducted a lateral movement task during which we induced stressors and tracked the movement accuracy of each participant over time. Stressors corresponded to organismic constraints (i.e., visual occlusion), task constraints (i.e., movement sensitivity), or both types of constraints in an alternating pattern. In order to determine resilience, we introduced a measure combining the strength of a stressor and the relaxation time. Across the three conditions, we found that resilience was enhanced rather than diminished over time. This supports the notion that stressors in the form of constraint alterations can be beneficial to human motor performance.

Highway navigation is often affected by complex topography, and the flat curve plays an important role in the horizontal alignment design of a highway. Many curves are formed, where visibility could be decreased. Thus, the indicative function of a traffic sign plays a crucial role in ensuring driving safety at the curve. Due to the blocked visibility, the probability of the traffic sign occlusion at the curve of operating highways is quite high. It is urgent to consider the clearing obstructions around traffic signs at curves during highway construction. In this study, the potential of visual occlusion for traffic signs on curved highways was investigated. Firstly, the driver’s visibility window that contains traffic signs was defined and criteria of visual occlusion were proposed. Secondly, a geometric occlusion design formula was established to mimic the visual recognition process of traffic signs on a curved highway, yielding the formula to calculate the visibility window. Finally, the occlusion design formula was applied into a case study of the Beijing-Hong Kong-Macau Expressway (Hunan section), in which visibility windows were calculated and analyzed. The obtained results verified the correctness and effectiveness of the occlusion design formula developed in this study.

Visibility can be identified as one of the critical determinants for the safety performance of autonomous vehicles (AVs) on unsignalized mid-block crosswalks (UMC), which may be significantly influenced by build-up environment and surrounding vehicles. This study investigates the safety performance when AVs interact with pedestrians approaching from far-side sidewalks to UMCs considering the visual occlusion of opposing vehicles. A mathematical model is proposed for judging the visibilities of objects from observers’ location under the impact of visual obstacles and is embedded into an agent-based pedestrian-vehicle interaction framework. Two yielding decision modules is assumed for AVs: The normal decision module implements the pedestrian priority rule simply based on the current detectable information, whereas the memory aid decision module extends AVs’ detection abilities by incorporating the memory data. Through simulation experiments, it is found that the percentages of short post encroachment time (%SPET) between AVs and far-side pedestrians reach peaks when the pedestrian flow rate is 300–400 ped/h. When opposing vehicles are in stationary queue conditions, %SPETs are only sensitive to the net distance between the last opposing vehicles in the queue and crosswalks (Dqueue). As the Dqueue decreases to lower than 15 m, %SPETs start to increase drastically. However, when opposing vehicles are in free flow conditions, %SPETs are influenced by multiple factors such as pedestrians’ crossing decisions, sizes and flow rates of opposing vehicles. Furthermore, only when opposing vehicles are in free flow conditions, memory aid AVs can significantly eliminate the impacts of opposite vehicles. Finally, several countermeasures are developed to enhance the visibility and safety at UMCs based on the findings of this study. The Qatar–Japan Research Collaboration Application Award [M-QJRC-2020-8] from Qatar University. This research is supported by The Kurata Grants No. 1397 of Hitachi Global Foundation.

When symmetry is present in the retinal image, a symmetry-sensitive network in the extrastriate visual areas activates, and response magnitude scales with degree of regularity. Is this activation driven by the regularity in the image, or can the network recover regularity of an object? We investigated whether the network responds to bilateral symmetry for dynamically occluded shapes, and thus responds to symmetry in the object. The stimulus was an irregular shape partly occluded by a rectangle. After 500 ms, the rectangle was displaced to the other side, occluding the previously visible half, and revealing the other half for 1000 ms. Therefore, no symmetry was present in the image at any point in time. Exp.1 and Exp.2 used vertical and horizontal axis of reflection, and in Exp. 3 there was no occluder. Participants could detect symmetry with >80% accuracy. More importantly, ERP analysis showed a symmetry-specific response from ∼300 ms after presentation of the second half of the shape. When integration was made from halves of asymmetric whole shapes (Exp.4), and when symmetry was not task-relevant (Exp.5), no symmetry response was recorded. The results show, for the first time, an electrophysiological evidence of symmetry representation in the brain obtained by assembling information over time into a unitary gestalt. The integration process occurs when observers look for symmetric matches between the parts, and only if these are perceived as belonging to the same object.

In this experimental study, we tested whether athletes’ judgments of affordances and of environmental features vary with psychological momentum (PM). We recruited golf, hockey, and tennis players, who were assigned to a positive or negative momentum condition. We designed a golf course on which participants made practice putts, after which they were asked to place the ball at their maximum “puttable” distance and to judge the hole size. Next, participants played a golf match against an opponent, in which the first to take a lead of 5 points would win the match. Participants were told that they could win a point by making the putt or by being closest to the hole. They wore visual occlusion goggles to prevent them from seeing the actual result, and the experimenter manipulated the scoring pattern to induce positive or negative PM. Participants in the positive momentum condition came back from a four-point lag to a four-point lead, whereas those in the negative momentum condition underwent the opposite scenario. We then asked the participants again to indicate their maximum puttable distance from the hole and to judge the hole size. After the manipulation, participants judged the maximum puttable distance to be longer in the positive momentum condition and shorter in the negative momentum condition. For the hole-size judgments, there were no significant effects. These results provide first indications for the idea that athletes’ affordances change when they experience positive PM compared to negative PM. This sheds a new light on the dynamics of perception-action processes and PM in sports.

Tactile sensing is critical for robotic grasping and manipulation of objects under visual occlusion. However, in contrast to simulations of robot arms and cameras, current simulations of tactile sensors have limited accuracy, speed, and utility. In this work, we develop an efficient 3D finite element method (FEM) model of the SynTouch BioTac sensor using an open-access, GPU-based robotics simulator. Our simulations closely reproduce results from an experimentally-validated model in an industry-standard, CPU-based simulator, but at 75x the speed. We then learn latent representations for simulated BioTac deformations and real-world electrical output through self-supervision, as well as projections between the latent spaces using a small supervised dataset. Using these learned latent projections, we accurately synthesize real-world BioTac electrical output and estimate contact patches, both for unseen contact interactions. This work contributes an efficient, freely-accessible FEM model of the BioTac and comprises one of the first efforts to combine self-supervision, cross-modal transfer, and sim-to-real transfer for tactile sensors., To be published in Proc. IEEE International Conference on Robotics and Automation (ICRA)

In humans, extrastriate visual areas are strongly activated by symmetry. However, perfect symmetry is rare in natural visual images. Recent findings showed that when parts of a symmetric shape are presented at different points in time the process relies on a perceptual memory buffer. Does this temporal integration need a retinotopic reference frame? For the first time we tested integration of parts both in the temporal and spatial domain, using a non-retinotopic frame of reference. In Experiment 1, an irregular polygonal shape (either symmetric or asymmetric) was partly occluded by a rectangle for 500 ms (T1). The rectangle moved to the opposite side to reveal the other half of the shape, whilst occluding the previously visible half (T2). The reference frame for the object was static: the two parts stimulated retinotopically corresponding receptive fields (revealed over time). A symmetry-specific ERP response from ~300 ms after T2 was observed. In Experiment 2 dynamic occlusion was combined with an additional step at T2: the new half-shape and occluder were rotated by 90°. Therefore, there was a moving frame of reference and the retinal correspondence between the two parts was disrupted. A weaker but significant symmetry-specific response was recorded. This result extends previous findings: global symmetry representation can be achieved in extrastriate areas non-retinotopically, through integration in both temporal and spatial domain.

Redirect walking is a technique that aims to manipulate the walking trajectories in immersive virtual reality settings by inducing unnoticeable displacements of the virtual environment. Taking into advantage the change blindness phenomenon, visual occlusion during eye blinks has been recently proposed to perform those displacements. This study determined the maximum unnoticeable displacement that can be performed in practical scenario, which proved to be near 0.8° of occlusion and disocclusion in both horizontal and vertical axes.

Flash bursts relay around vegetation across the swarm, illuminating the role of the environment in shaping self-organization., Fireflies flashing in unison is a mesmerizing manifestation of animal collective behavior and an archetype of biological synchrony. To elucidate synchronization mechanisms and inform theoretical models, we recorded the collective display of thousands of Photinus carolinus fireflies in natural swarms, and provide the first spatiotemporal description of the onset of synchronization. At low firefly density, flashes appear uncorrelated. At high density, the swarm produces synchronous flashes within periodic bursts. Using three-dimensional reconstruction, we demonstrate that flash bursts nucleate and propagate across the swarm in a relay-like process. Our results suggest that fireflies interact locally through a dynamic network of visual connections defined by visual occlusion from terrain and vegetation. This model illuminates the importance of the environment in shaping self-organization and collective behavior.

Objective The aim of this review is to identify how visual occlusion contributes to our understanding of attentional demand and spare visual capacity in driving and the strengths and limitations of the method. Background The occlusion technique was developed by John W. Senders to evaluate the attentional demand of driving. Despite its utility, it has been used infrequently in driver attention/inattention research. Method Visual occlusion studies in driving published between 1967 and 2020 were reviewed. The focus was on original studies in which the forward visual field was intermittently occluded while the participant was driving. Results Occlusion studies have shown that attentional demand varies across situations and drivers and have indicated environmental, situational, and inter-individual factors behind the variability. The occlusion technique complements eye tracking in being able to indicate the temporal requirements for and redundancy in visual information sampling. The proper selection of occlusion settings depends on the target of the research. Conclusion Although there are a number of occlusion studies looking at various aspects of attentional demand, we are still only beginning to understand how these demands vary, interact, and covary in naturalistic driving. Application The findings of this review have methodological and theoretical implications for human factors research and for the development of distraction monitoring and in-vehicle system testing. Distraction detection algorithms and testing guidelines should consider the variability in drivers’ situational and individual spare visual capacity.

The fiber surface generalizes the popular isosurface to multi-fields, so that pre-images can be visualized as surfaces. As with the isosurface, however, the fiber surface suffers from visual occlusion. We propose to avoid such occlusion by restricting the components to only the relevant ones with a new component-wise flexing algorithm. The approach, flexible fiber surface, generalizes the manipulation idea found in the flexible isosurface for the fiber surface. The flexible isosurface in the original form, however, relies on the contour tree. For the fiber surface, this corresponds to the Reeb space, which is challenging for both the computation and user interaction. We thus take a Reeb-free approach, in which one does not compute the Reeb space. Under this constraint, we generalize a few selected interactions in the flexible isosurface and discuss the implication of the restriction.

Free kicks are an important goal scoring opportunity in football. It is an unwritten rule that the goalkeeper places a wall of defending players with the aim of making scoring harder for the attacking team. However, the defensive wall can occlude the movements of the kicker, as well as the initial part of the ball trajectory. Research on one-handed catching suggests that a ball coming into view later will likely delay movement initiation and possibly affect performance. Here, we used virtual reality to investigate the effect of the visual occlusion of the initial ball trajectory by the wall on the performance of naïve participants and skilled goalkeepers. We showed that movements were initiated significantly later when the wall was present, but not by the same amount as the duration of occlusion (~200ms, versus a movement delay of ~70-90ms); movements were thus initiated sooner after the ball came into view, based on less accumulated information. For both naïve participants and skilled goalkeepers this delayed initiation significantly affected performance (i.e., 3.6cm and 1.5cm larger spatial hand error, respectively, not differing significantly between the groups). These performance reductions were significantly larger for shorter flight times, reaching increased spatial errors of 4.5cm and 2.8cm for both groups, respectively. Further analyses showed that the wall-induced performance reduction did not differ significantly between free kicks with and without sideward curve. The wall influenced early movement biases, but only for free kicks with curve in the same direction as the required movement; these biases were away from the final ball position, thus hampering performance. Our results cannot suggest an all-out removal of the wall–this study only considered one potential downside–but should motivate goalkeepers to continuously evaluate whether placing a wall is their best option. This seems most pertinent when facing expert free kick takers for whom the wall does not act as a block (i.e., whose kicks consistently scale the wall).

Visual distraction by secondary in-car tasks is a major contributing factor in traffic incidents. In-car user interface design may mitigate these negative effects but to accomplish this, design factors’ visual distraction potential should be better understood. The effects of touch screen size, user interface design, and subtask boundaries on in-car task's visual demand and visual distraction potential were studied in two driving simulator experiments with 48 participants. Multilevel modeling was utilized to control the visual demands of driving and individual differences on in-car glance durations. The 2.5” larger touch screen slightly decreased the in-car glance durations and had a diminishing impact on both visual demand and visual distraction potential of the secondary task. Larger relative impact was discovered concerning user interface design: an automotive-targeted application decreased the visual demand and visual distraction potential of the in-car tasks compared to the use of regular smartphone applications. Also, impact of subtask boundaries was discovered: increase in the preferred number of visual or visual-manual interaction steps during a single in-car glance (e.g., pressing one button vs. typing one word) increased the duration of the in-car glance and its visual distraction potential. The findings also emphasize that even if increasing visual demand of a task – as measured by in-car glance duration or number of glances – may increase its visual distraction potential, these two are not necessarily equal. peerReviewed

Previous research on skill acquisition has shown that learners seem to prefer receiving knowledge of results (KR) about those trials in which they have performed more accurately. In the present study, we assessed whether this preference leads to an advantage in terms of skill acquisition, transfer, and retention of their capacity to extrapolate the motion of decelerating objects during periods of visual occlusion. Instead of questionnaires, we adopted a more direct approach to investigate learners' preferences for KR. Participants performed 90 trials of a motion extrapolation task (acquisition phase) in which, every three trials, they could decide between receiving KR about their best or worst performance. Retention and transfer tests were carried out 24 hr after the acquisition phase, without KR, to examine the effects of the self-selected KR on sensorimotor learning. Consistent with the current literature, a preference for receiving KR about the most accurate performance was observed. However, participants' preferences were not consistent throughout the experiment as less than 10% (N = 40) selected the same type of KR in all their choices. Importantly, although preferred by most participants, KR about accurate performances had detrimental effects on skill acquisition, suggesting that learners may not always choose the KR that will maximize their learning experiences and skill retention. (PsycINFO Database Record

Our interaction with objects is facilitated by the availability of visual feedback. Here, we investigate how and when visual feedback affects the way we grasp an object. Based on the main views on grasping (reach-and-grasp and double-pointing views), we designed four experiments to test: (1) whether the availability of visual feedback influences the digits independently, and (2) whether the absence of visual feedback affects the initial part of the movement. Our results show that occluding (part of) the hand’s movement path influences the movement trajectory from the beginning. Thus, people consider the available feedback when planning their movements. The influence of the visual feedback depends on which digit is occluded, but its effect is not restricted to the occluded digit. Our findings indicate that the control mechanisms are more complex than those suggested by current views on grasping.

OCCUPATIONAL APPLICATIONS Our study examined the influences of visual occlusion on healthy adults during the performance of hand coordination tasks. We found that central vision occlusion, similar ...

Objective To assess the attentional demand of different contextual factors in driving. Background The attentional demand on the driver varies with the situation. One approach for estimating the attentional demand, via spare capacity, is to use visual occlusion. Method Using a 3 × 5 within-subjects design, 33 participants drove in a fixed-base simulator in three scenarios (i.e., urban, rural, and motorway), combined with five fixed occlusion durations (1.0, 1.4, 1.8, 2.2, and 2.6 s). By pressing a microswitch on a finger, the driver initiated each occlusion, which lasted for the same predetermined duration within each trial. Drivers were instructed to occlude their vision as often as possible while still driving safely. Results Stepwise logistic regression per scenario indicated that the occlusion predictors varied with scenario. In the urban environment, infrastructure-related variables had the biggest influence, whereas the distance to oncoming traffic played a major role on the rural road. On the motorway, occlusion duration and time since the last occlusion were the main determinants. Conclusion Spare capacity is dependent on the scenario, selected speed, and individual factors. This is important for developing workload managers, infrastructural design, and aspects related to transfer of control in automated driving. Application Better knowledge of the determinants of spare capacity in the road environment can help improve workload managers, thereby contributing to more efficient and safer interaction with additional tasks.

Background Response inhibition involves suppressing automatic, but unwanted action, which allows for behavioral flexibility. This capacity could theoretically contribute to fall prevention, especially in the cluttered environments we face daily. Although much has been learned from cognitive psychology regarding response inhibition, it is unclear if such findings translate to the intensified challenge of coordinating balance recovery reactions. Research question Is the ability to stop a prepotent response preserved when comparing performance on a standard test of response inhibition versus a reactive balance test where compensatory steps must be occasionally suppressed? Methods Twelve young adults completed a stop signal task and reactive balance test separately. The stop signal task evaluates an individual’s ability to quickly suppress a visually-cued button press upon hearing a ‘stop’ tone, and provides a measure of the speed of response inhibition called the Stop Signal Reaction Time (SSRT). Reactive balance was tested by releasing participants from a supported lean position, in situations where the environment was changed during visual occlusion. Upon receiving vision, participants were required to either step to regain balance following cable release (70% of trials), or suppress a step if an obstacle was present (30% of trials). The early muscle response of the stepping leg was compared between the ‘step blocked’ and ‘step allowed’ trials to quantify step suppression. Results SSRT was correlated with muscle activation of the stepping leg when sufficient time was provided to view the response environment (400 ms). Individuals with faster SSRTs exhibited comparably less leg muscle activity when a step was blocked, signifying a superior ability to inhibit an unwanted step. Significance Performance on a standardized test of response inhibition is related to performance on a reactive balance test where automated stepping responses must occasionally be inhibited. This highlights a generalizable neural mechanism for stopping action across different behavioral contexts.

Objective: We studied the utility of occlusion distance as a function of task-relevant event density in realistic traffic scenarios with self-controlled speed. Background: The visual occlusion technique is an established method for assessing visual demands of driving. However, occlusion time is not a highly informative measure of environmental task-relevant event density in self-paced driving scenarios because it partials out the effects of changes in driving speed. Method: Self-determined occlusion times and distances of 97 drivers with varying backgrounds were analyzed in driving scenarios simulating real Finnish suburban and highway traffic environments with self-determined vehicle speed. Results: Occlusion distances varied systematically with the expected environmental demands of the manipulated driving scenarios whereas the distributions of occlusion times remained more static across the scenarios. Systematic individual differences in the preferred occlusion distances were observed. More experienced drivers achieved better lane-keeping accuracy than inexperienced drivers with similar occlusion distances; however, driving experience was unexpectedly not a major factor for the preferred occlusion distances. Conclusion: Occlusion distance seems to be an informative measure for assessing task-relevant event density in realistic traffic scenarios with self-controlled speed. Occlusion time measures the visual demand of driving as the task-relevant event rate in time intervals, whereas occlusion distance measures the experienced task-relevant event density in distance intervals. Application: The findings can be utilized in context-aware distraction mitigation systems, human–automated vehicle interaction, road speed prediction and design, as well as in the testing of visual in-vehicle tasks for inappropriate in-vehicle glancing behaviors in any dynamic traffic scenario for which appropriate individual occlusion distances can be defined.

Background: In persons with Parkinson&rsquo, s disease (pwPD) any additional somatosensory or distractor interference can influence the posture. When deprivation of vision and dual-task are associated, the effect on biomechanical performance is less consistent. The aim of this study was to evaluate the role of the visual deprivation and a cognitive task on the static balance in earlier stage PD subjects. Methods: Fifteen off-medication state pwPD (9 women and 6 men), 67.7 &plusmn, 7.3 years old, diagnosed PD since 5.4 &plusmn, 3.4 years, only Hoehn and Yahr state 2 and fifteen young control adults (7 women and 8 men) aged 24.9 &plusmn, 4.9 years, performed semi-tandem task under four randomized experimental conditions: eyes opened single-task, eyes closed single-task, eyes opened dual-task and eyes closed dual-task. The center of pressure (COP) was measured using a force plate and electromyography signals (EMG) of the ankle/hip muscles were recorded. Traditional parameters, including COP pathway length, ellipse area, mediolateral/anteroposterior root-mean-square and non-linear measurements were computed. The effect of vision privation, cognitive task, and vision X cognitive was investigated by a 2 (eyes opened/eyes closed) &times, 2 (postural task alone/with cognitive task) repeated-measures ANOVA after application of a Bonferroni pairwise correction for multiple comparisons. Significant interactions were further analyzed using post-hoc tests. Results: In pwPD, both COP pathway length (p &lt, 0.01), ellipse area (p &lt, 0.01) and mediolateral/anteroposterior root-mean-square (p &lt, 0.01) were increased with the eyes closed, while the dual-task had no significant effect when compared to the single-task condition. Comparable results were observed in the control group for who COP pathway was longer in all conditions compared to eyes opened single-task (p &lt, 0.01) and longer in conditions with eyes closed compared to eyes opened dual-task (p &lt, 0.01). Similarly, all differences in EMG activity of pwPD were exclusively observed between eyes opened vs. eyes closed conditions, and especially for the forward leg&rsquo, s soleus (p &lt, 0.01) and backward tibialis anterior (p &lt, 0.01). Conclusions: These results in pwPD without noticeable impairment of static balance encourage the assessment of both visual occlusion and dual-task conditions when the appearance of significant alteration during the dual-task could reveal the subtle worsening onset of the balance control.

This study investigated the influence of age and visual occlusion on fast reach-to-grasp movements. The effect of visual occlusion on reach-to-grasp movement was examined using a task that heavily relies on feed-forward control. Three groups of healthy adults aged 22, 49 and 65 on average performed fast reach-to-grasp movements with full visual and partial visual occlusion conditions of the hand during the initial part of movement. Regarding the effect of age, the all parameters of reach-to-grasp movement were deteriorated with age, except relative time to maximum velocity and spatial coordination. Regarding the effect of visual condition, participants reached with prolonged movement time, lower peak velocity, and later occurrences of peak velocity and peak aperture, as well as decrease in spatial coordination. Regarding the effect of age on visual condition, visual occlusion resulted in a longer movement time and delayed time to maximum velocity in middle-aged and older groups compared to full vision, but the difference was not observed in the younger groups. Conclusion: Reach-to-grasp performance deteriorated with age and the performance was affected when vision of the hand at initial movement was occluded. Overall, movement performance in middle-aged and older adults was affected by visual occlusion, whereas it was unaffected in younger adults. The results indicate that visual feedback of the hand at initial movement is important to control reach-to-grasp movement of middle-aged and older adults during real tasks.

PurposeDespite its well-known importance in sports, agility is ambiguously defined and lack of research. Shuttle Run (SR) is commonly used to improve the on-court agility of badminton players. Reactive Initiation Training (RIT) contrasts SR in that it only demands rapid generation of initiation step toward the direction of shuttlecock. The current study compared SR with RIT to determine which one is more effective for improving on-court agility of novice badminton players.Method20 novice badminton players were split in half to receive either RIT or SR on court for five days. Before and after training, participants were assessed on their ability to intercept the shuttlecocks randomly thrown by a coach to six corners of the court with and without visual occlusion of the coach. All trials of interception were recorded for video analysis of initiation time, running time and total time.ResultsThe mean total times were greater with visual occlusion and varied systematically with the position of interception. Both training methods shortened the mean running time, however, only RIT additionally reduced the initiation time and its proportion on those time-consuming positions in the occluded condition.ConclusionRIT is more effective than SR to improve the on-court agility of novice badminton players.

Aging causes the detriment of sensory information that reflects the quality of postural control. The use of light touch has been suggested as a strategy to reduce postural sway even in the absence of vision. However, the effects of this strategy in unstable situations on the support base are unclear. The aim of this study was to analyze the effects of visual occlusion and light touch on the balance of elderly and young adult women on an unstable platform. Twenty elderly women (69.4±6.7 years) and twenty young adult women (20.6±3.2years) performed three attempts at the task which consisted of maintaining balance on an unstable platform on a bipedal base for twenty seconds, with medial-lateral perturbation, in four conditions. The Mann-Whitney U test showed that the elderly women presented worse balance compared to the young adult women in all conditions (p

Besides motorists, also motorcyclists need safer user interfaces to interact with useful applications on the road. In this paper, distraction effects of in-vehicle tasks conducted with a head-up display (HUD) for motorcyclists were compared to smartphone tasks with 24 participants in a driving simulator. Compared to the smartphone tasks, the head-up display tasks decreased the percentage of inappropriately long glances by 45 percent. The head-up display tasks were also experienced as less demanding than the smartphone tasks. Additionally, the use of head-up display for navigation did not lead to gaze concentration effects compared to baseline driving. The head-up display is concluded to be a safer option for the tested tasks for motorcyclists than a smartphone. Based on earlier research, we assume that the use of peripheral vision allowed drivers to better maintain situational awareness during the head-up display tasks compared to the head-down smartphone tasks. In addition, the easy-to-learn haptic design of the head-up display handlebar controller could be used without vision. peerReviewed

Infants possess the remarkable capacity to perceive occluded movements as ongoing and coherent. Little is known about the neural mechanisms that enable internal representation of conspecifics' and inanimate objects' movements during visual occlusion. In this study, 10-month-old infants watched briefly occluded human and object movements. Prior to occlusion, continuous and distorted versions of the movement were shown. EEG recordings were used to assess neural activity assumed to relate to processes of attention (occipital alpha), memory (frontal theta), and sensorimotor simulation (central alpha) before, during, and after occlusion. Oscillatory activity was analyzed using an individualized data approach taking idiosyncrasies into account. Results for occipital alpha were consistent with infants' preference for attending to social stimuli. Furthermore, frontal theta activity was more pronounced when tracking distorted as opposed to continuous movement, and when maintaining object as opposed to human movement. Central alpha did not discriminate between experimental conditions. In sum, we conclude that observing occluded movements recruits processes of attention and memory which are modulated by stimulus and movement properties.

Three text entry methods were compared in a driving simulator study with 17 participants. Ninety-seven drivers’ occlusion distance (OD) data mapped on the test routes was used as a baseline to evaluate the methods’ visual distraction potential. Only the voice recognition-based text entry tasks passed the set verification criteria. Handwriting tasks were experienced as the most demanding and the voice recognition tasks as the least demanding. An individual in-car glance length preference was found, but against expectations, drivers’ ODs did not correlate with incar glance lengths or visual short-term memory capacity. The handwriting method was further studied with 24 participants with instructions and practice on writing eyeson-road. The practice did not affect the test results. The findings suggest that handwriting could be visually less demanding than touch screen typing but the reliability of character recognition should be improved or the driver well-experienced with the method to minimize its distraction potential. peerReviewed

Glaucoma is a key cause of peripheral visual field loss and increases risk of a vehicle crash. Patients may be unaware of their visual loss and of hazards in the driving panorama. Standard clinical automated perimetry, the “gold standard” for monitoring glaucoma progression, lacks external validity to evaluate functional effect of visual field loss in driving environments. We developed and piloted a new technique to study the effects of glaucoma in a panoramic (290 forward FOV) simulated driving environment. Preliminary results in 11 drivers (7 with glaucoma and 4 with suspected glaucoma): (1) demonstrate the relationship between standard clinical perimetry and driving simulator visual fields, (2) replicate clinical evidence of glaucoma-related peripheral visual field loss, and (3) show added visual field loss due to visual occlusion by in-cab geometry.

Effect of arm visibility on immediate manual preference was evaluated in 5-month-old infants on the task of reaching for a toy. Manual preference was assessed under full vision, and then in consecutive intervals in which vision of the preferred arm was occluded. Results showed that preferred arm visual occlusion led to reduced frequency of its use, with weakened persistence of that effect in the ensuing reestablishment of full vision. These results reveal that visual contact with the arms modulates their selection to perform reaching movements.

As agrarian practices return to the urban space, a lack of understanding between the urban farmers and local city officials is stunting the development and economic sustainability of urban agriculture. Many promoters of urban agriculture fail to grasp the modern reality of operating a significant venture within a zoned municipal space. A failure to account for all potential stakeholders in the planning of these agricultural projects can cause unforeseen delays in execution and economic disaster. The needs of the agricultural installation must be balanced with the complexities of the city systems, and modern zoning procedures take multiple perspectives into account. There are numerous variables and considerations that must be evaluated in the creation of an urban farm that developers accustomed to working within the rural environment may not naturally include in their thinking. City planning and neighborhood integration must be addressed to ensure smooth geographic transition between the farming operation and further local real estate market development. The urban agricultural project developer will be required to demonstrate that the logistical needs of the enterprise can be accommodated within the existing infrastructure or be willing to upgrade the lacking requirement. Odor abatement and visual occlusion may be required. These complex elements of successfully installing an agricultural enterprise within an urban environment often frustrate successful project managers with agrarian backgrounds and cause them to pay minimal attention to the requirements of urban operation. Unfortunately, it can be clearly demonstrated that to do so is fraught with peril. Without thoughtful design, many urban agriculture efforts have slow growth, and the impact of these design failures on the progression of these enterprises is immense.

Um aspecto de interesse sobre a formação da preferência manual humana em idades precoces é a extensão em que ela é afetada por informações aferentes. O objetivo deste estudo foi investigar o efeito da oclusão visual do braço preferido sobre a preferência manual e desempenho motor em bebês. Participaram cinco bebês com cinco meses de idade, que realizaram alcances com visão plena ou oclusão visual do braço preferido. O desempenho motor foi avaliado por meio de medidas cinemáticas. Os resultados indicaram que a oclusão visual induziu redução da frequência de alcances unimanuais com o braço ocluído durante e imediatamente após a oclusão visual. Oclusão visual não alterou o desempenho motor. Estes resultados indicam que a formação da preferência manual durante o desenvolvimento motor é afetada pela disponibilidade de informação visual dos braços, embora os bebês pareçam ter pouca capacidade de usar a visão para controle motor.