Increasing Career Center Accessibility for the Blind

To improve career planning services for visually impaired persons, the career center at Florida State University developed a self-directed program. This article describes strategies for making career information materials and resources more accessible to the blind.     

Enhancing the mental representations of space used by blind pedestrians, based on an image schemata model

The configuration of mental representation of space plays a major role in successful navigational activities. Therefore, navigational assistance for pedestrians who are blind should help them to better configure their mental representation of the environment. In this paper, we propose and exploit a computational model for the mental representation of urban areas as an aid to orientation and navigation for visually impaired pedestrians. Our model uses image schemata to capture the spatial semantics and configural elements of urban space necessary for this purpose. These image schemata are schematic structures that are continually requested by individuals in their perception, bodily movement and interaction with surrounding objects. Our proposed model also incorporates a hierarchical structure to provide different levels of detail tied to appropriate spatial perspectives at each scale. We presume that such computational model will help us to develop an appropriate structure of spatial data used to assist the target population. At the end of the paper, we illustrate the utility of our configural model by developing a typical scenario for the navigation of a blind pedestrian in an urban area.     

The importance of alignment in blind subjects' use of tactual maps

An experiment was conducted to test for the presence of alignment effects (previously found in sighted map users) in blind and visually impaired subjects using tactual maps. The term 'alignment effects' refers to the fact that when points represented as further up on a map do not correspond to points forward from the user in the environment, errors in the directional judgments made by subjects are greatly increased. The results show that alignment effects do exist in blind and visually impaired map users. Blind subjects encoded maps using the 'up equals forward' rule, and demonstrated some similarity to sighted subjects in the types of errors made. There was also some indication of improved performance over repeated trials. Differences between blind and sighted subjects were also found and were tentatively attributed to visual experience with object transformations and/or representational variables. Subject background variables were also investigated and some relationships between background of the subject and performance were drawn.     

Most earcons do not interfere with spoken passage comprehension

A cross‐modal dual attention experiment was completed by 198 undergraduates in three blocks that each consisted of an orientation task and a concurrent listening task. For the orientation task, participants located regions on an LCD that were cued by speech or one of four types of symbolic auditory cues (i.e. earcons); the concurrent task required participants to listen to and answer questions about GRE sample test passages. Results indicated the orientation task had no effect on comprehension of the passages compared to a passage‐only control for four of the five auditory cue types. All auditory cues resulted in high performance for the orientation task, with speech and complex sounds exhibiting the highest performance. Implications for auditory display design and for assistive technologies for visually impaired persons are discussed. Copyright © 2008 John Wiley & Sons, Ltd.     

Using traffic light information as navigational cues: implications for navigation system design

There are compelling research findings that using landmarks such as traffic lights as navigation cues can enhance the acceptability, usability and safety of vehicle navigation systems. In this study, 30 participants undertook an on-road trial using simulated navigation instructions that omitted any reference to distance-to-turn, and instead incorporated information requiring drivers to count traffic lights and pedestrian lights. The study results confirmed that traffic lights can be used as navigation cues even when the density of traffic lights along a stretch of road is high and that the term “set of traffic lights” results in slightly better performance than “traffic lights” alone. Factors other than density were found to have an effect on navigation performance. More errors were made if the target turn was at a pedestrian light and if the turn was visually complex or concealed. In the absence of a navigation task, most drivers did not differentiate between traffic and pedestrian lights when counting the occurrences and only experienced difficulty in counting when the number exceeded 4. Implications for the design of future navigation systems are highlighted.     

Haptic perception of the horizontal by blind and low-vision individuals.

We examined haptic perception of the horizontal in visually impaired people. Blind people (late blind and congenitally blind), persons with very low vision, and blindfolded sighted individuals felt raised-line drawings of jars at four angles. They had to demonstrate their understanding that water remains horizontal, despite jar tilt, by selecting the correct raised-line drawing given four choices. Low-vision subjects, with near perfect scores, performed significantly better than the other groups of subjects. While the late-blind and blindfolded sighted subjects performed slightly better than the congenitally blind participants, the difference between the late-blind and congenitally blind groups was nonsignificant. The performance of the congenitally blind subjects indicates that visual experience is not necessary for the development of an understanding that water level stays horizontal, given container tilt.     

Computer use by the visually impaired

Several recent developments have made computers accessible to the blind and partially sighted: hard-copy (paper) and softcopy (raised-pin) braille output, magnified high-resolution characters, and synthetic speech. We report survey data on these users’ computer education, tasks, and goals; their hardware uses and preferences, particularly for special-purpose I/O devices; and seven classes of human-factors problems that affect the use of these I/O devices by the visually impaired.     

盲人建构陌生环境空间表征的策略及其作用

空间表征对于盲人定向行走具有重要意义。以往研究者集中探讨早期视觉经验缺失对于盲人空间表征的影响, 较少探究空间表征建构的过程性因素, 即探路策略对于盲人空间表征的影响。本研究采用现场实验的方法探究了盲人建构陌生环境空间表征采用的策略及其作用。结果发现：视觉经验缺失对盲人陌生环境空间表征能力造成了不利影响, 然而, 被试运用有效的策略可以弥补视觉缺失带来的损失, 且利用空间关系策略的个体所建构的空间表征更为精确, 定向行走效率也更高。     

How do people with cognitive functional limitations post-stroke manage the use of buses in local public transport?

People with cognitive functional limitations (CFLs) have rarely been the focus of research dealing with road users and their needs. The aim of the present study was to describe how people with CFL post-stroke manage in their use of buses in the framework of their outdoor mobility, and to find out what difficulties, but also what opportunities, they experienced when moving from origin to destination using buses in public transport. Semi-structured interviews combined with participant observations during bus trips with eight persons were performed. Several barriers that have the potential to restrict autonomous outdoor mobility were identified. These barriers were not only represented by well-known infrastructure problems (high pavement curbs, etc.) or ergonomic shortcomings in the buses but, even more so, by specific issues relevant for persons with CFL, e.g. having to cross a road on their way to the bus stop, which poses problems of interaction with fast-moving car traffic. Obtaining all the necessary information prior to and during the trip is difficult and produces insecurity. Often, communication with the bus drivers, not least in connection with the search for information, causes extra stress. Lack of self-confidence and feelings of inferiority add to these problems. Measures to control vehicle speeds, to optimise the communication style of bus drivers with their customers, and to improve customers’ access to information are recommended. Training measures to reassure persons with CFL in connection with their use of the public space are suggested.     

Indirect interception actions by blind and visually impaired perceivers: Echolocation for interceptive actions

Vernat, J.-P. & Gordon, M. S. (2010). Indirect interception actions by blind and visually impaired perceivers: Echolocation for interceptive actions. Scandinavian Journal of Psychology, 51, 75–83.
This research examined the acoustic information used to support interceptive actions by the blind. Congenitally blind and severely visually impaired participants (all wearing an opaque, black eye-mask) were asked to listen to a target ball rolling down a track. In response, participants rolled their own ball along a perpendicular path to intercept the target. To better understand what information was used the echoic conditions and rolling dynamics of the target were varied across test sessions. In addition the rolling speed of the target and the distance of the participant from the target were varied across trials. Results demonstrated that participants tended to perform most accurately at moderate speeds and distances, overestimating the target's arrival at the fastest speed, and underestimating it at the slowest speed. However, changes to the target's dynamics, that is, the amount of deceleration it underwent on approach, did not strongly influence performance. Echoic conditions were found to affect performance, as participants were slightly more accurate in conditions with faster, higher-intensity echoes. Based on these results blind individuals in this research seemed to be using spatial and temporal cues to coordinate their interceptive actions.     

Mental imagery,reasoning, and blindness

Although reasoning seems to be inextricably linked to seeing in the “mind's eye”, the evidence is equivocal. In three experiments, sighted, blindfolded sighted, and congenitally totally blind persons solved deductive inferences based on three sorts of relation: (a) visuo-spatial relations that are easy to envisage either visually or spatially, (b) visual relations that are easy to envisage visually but hard to envisage spatially, and (c) control relations that are hard to envisage both visually and spatially. In absolute terms, congenitally totally blind persons performed less accurately and more slowly than the sighted on all such tasks. In relative terms, however, the visual relations in comparison with control relations impeded the reasoning of sighted and blindfolded participants, whereas congenitally totally blind participants performed the same with the different sorts of relation. We conclude that mental images containing visual details that are irrelevant to an inference can even impede the process of reasoning. Persons who are blind from birth—and who thus do not tend to construct visual mental images—are immune to this visual-impedance effect.     

Mental imagery, reasoning, and blindness

Although reasoning seems to be inextricably linked to seeing in the “mind's eye”, the evidence is equivocal. In three experiments, sighted, blindfolded sighted, and congenitally totally blind persons solved deductive inferences based on three sorts of relation: (a) visuo-spatial relations that are easy to envisage either visually or spatially, (b) visual relations that are easy to envisage visually but hard to envisage spatially, and (c) control relations that are hard to envisage both visually and spatially. In absolute terms, congenitally totally blind persons performed less accurately and more slowly than the sighted on all such tasks. In relative terms, however, the visual relations in comparison with control relations impeded the reasoning of sighted and blindfolded participants, whereas congenitally totally blind participants performed the same with the different sorts of relation. We conclude that mental images containing visual details that are irrelevant to an inference can even impede the process of reasoning. Persons who are blind from birth—and who thus do not tend to construct visual mental images—are immune to this visual-impedance effect.     

即时通讯软件使用动机的探讨

鉴于当前流行的即时通讯软件(instant messaging,IM)既广泛集成了互联网的功能和服务,又包含了其独特的功能和服务,笔者借鉴互联网使用动机的研究,提出了两个基于IM环境的用户使用动机的假设模型:其一是包含人际沟通、娱乐休闲、自我展示和信息获取动机的四因素模型;其二是包含人际沟通、娱乐休闲和信息获取动机的三因素模型。本研究以主流的大学生IM用户为对象,通过验证性因素分析的检验结果发现,大学生IM用户使用IM主要在于满足其人际沟通、娱乐休闲和信息获取三种动机。进一步的二阶验证性因素分析表明,首要动机是人际沟通,次要动机是娱乐休闲与信息获取。基于上述结果,笔者提出了关于IM产品设计的建议。     

Visualizing individual differences in Web navigation: STRATDYN, a tool for analyzing navigation patterns

Navigational behavior on the Web can be analyzed with different methods. Log file data are an important source of behavioral traces of navigation. In this paper, we first discuss existing approaches to the classification and visualization of movement sequences that are important for understanding Web navigation. We then present STRATDYN, a tool that provides meaningful quantitative and qualitative measures from server-generatedlog files, as well as easy-to-follow visualizations of navigational paths of individual users. We demonstrate the usefulness of this new approach by reporting the results of two studies (with 44 students in education and vocational training), which show that navigational effectiveness is positively related to the ability to concentrate and selectivelyfocus attention, as measuredby the D2 Test of Attention and the FWIT, a German version of the Stroop test. Finally, we discuss implications for further research in this area and for the continuing development of the approach presented.     

Neue Medien für die gesundheitliche Versorgung

The rapid development of information and communication technologies and their broad availability open up new opportunities for psychosocial service provision. Information materials provided via the internet have the potential to improve users’ competences and thus influence their health care utilisation by allowing for more active participation. Furthermore, a great variety of e-health interventions have been developed to improve care. These interventions are not limited to specific areas of service provision but span the whole range from prevention to aftercare programs. It has been shown that such technology-enhanced interventions can help to bridge gaps in health care services in an effective way.     

The generation of vibrotactile patterns on a linear array: influences of body site, time, and presentation mode

In order to provide information regarding orientation or direction, a convenient code employs vectors (lines) because they have both length and direction. Potential users of such information, encoded tactually, could include persons who are blind, as well as pilots, astronauts, and scuba divers, all of whom need to maintain spatial awareness in their respective unusual environments. In these situations, a tactile display can enhance environmental awareness. In this study, optimal parameters were explored for lines presented dynamically to the skin with vibrotactile arrays on three body sites, with veridical and saltatory presentation modes. Perceived length, straightness, spatial distribution, and smoothness were judged while the durations of the discrete taps making up the "drawn" dotted lines and the times between them were varied. The results indicate that the two modes produce equivalent sensations and that similar sets of timing parameters, within the ranges tested, result in "good" lines at each site.     

Spatial asymmetries in tactile discrimination of line orientation: a comparison of the sighted, visually impaired, and blind

Thresholds for tactile discrimination of stimulus orientation discrepancy from standard or referent vertical, horizontal, and diagonal orientations were determined for sighted, visually impaired, and blind subject groups. The stimuli were presented to the ventral distal portion of the tip of the subject's left index finger via an Optacon. Although the subject groups did not differ in overall discrimination accuracy, for each group the deviations from vertical and horizontal standard orientations were discriminated reliably more accurately than the deviations from standard diagonals, ie the oblique effect was obtained. The bases for this tactual spatial anisotrophic effect appear to reflect both sensory--neurological and experiential factors.     

Memory for movement in blind children: the role of previous visual experience

The role of previous visual experience in the reproduction of a criterion movement was examined in sighted, late-blinded, and congenitally blind children. Results showed that the congenitally blind reproduce movements at a low level of accuracy compared with the other two groups. Detailed analysis showed that although the congenitally blind could reproduce the extent of the movement accurately, the movement was poorly reproduced in terms of its orientation to the criterion movement and its orientation from a reference point. The role of prior vision in establishing a frame of reference is discussed.     

Reduced Attention and the Performance of “Automated” Movements

3 repetitive movements were studied. These were a blind movement between 2 stops, a visually guided movement to a line and a blind movement which had to be terminated at a previously learned position. Previous work had shown that the first of the three caused no interference with RT to a secondary signal presented during the movement, while the other two did interfere. Ss either performed the movement task alone, together with an attention demanding key positioning task, or under an instruction to think about something else. The variability of movement and pause time was used to score the movement tasks. When the movement was performed alone, variability was least for the blind movement between stops and most for the blind movement with a remembered target All tasks showed increased variability when performed with the subsidiary key task. The instruction to think about something else generally increased variability but not significantly. The task component showing the least influence of the secondary task was the variability of movement distance in the blind task without stops.