Invisible Boundary Research Articles

Eye movements and display change detection during reading.

In the boundary change paradigm (Rayner, 1975), when a reader's eyes cross an invisible boundary location, a preview word is replaced by a target word. Readers are generally unaware of such changes due to saccadic suppression. However, some readers detect changes on a few trials and a small percentage of them detect many changes. Two experiments are reported in which we combined eye movement data with signal detection analyses to investigate display change detection. On each trial, readers had to indicate if they saw a display change in addition to reading for meaning. On half the trials the display change occurred during the saccade (immediate condition); on the other half, it was slowed by 15-25 ms (delay condition) to increase the likelihood that a change would be detected. Sentences were presented in an alternating case fashion allowing us to investigate the influence of both letter identity and case. In the immediate condition, change detection was higher when letters changed than when case changed corroborating findings that word processing utilizes abstract (case independent) letter identities. However, in the delay condition (where d' was much higher than the immediate condition), detection was equal for letter and case changes. The results of both experiments indicate that sensitivity to display changes was related to how close the eyes were to the invalid preview on the fixation prior to the display change, as well as the timing of the completion of this change relative to the start of the post-change fixation.

Unexpected changes in direction of motion attract attention

Under some circumstances, moving objects capture attention. Whether a change in the direction of a moving object attracts attention is still unexplored. We investigated this using a continuous tracking task. In Experiment 1, four grating patches changed smoothly and semirandomly in their positions and orientations, and observers attempted to track the orientations of two of them. After the stimuli disappeared, one of the two target gratings was queried and observers reported its orientation; hence direction of the gratings' motion across the screen was an irrelevant feature. Despite the irrelevance of its motion, when the nonqueried grating had collided with an invisible boundary within the last 200 msec of the trial, accuracy reporting the queried grating was worse than when it had not. Attention was likely drawn by the unexpected nature of these changes in direction of motion, since the effect was eliminated when the boundaries were visible (Experiment 2). This tendency for unexpected motion changes to attract attention has important consequences for the monitoring of objects in everyday environments.

Preview fixation duration modulates identical and semantic preview benefit in Chinese reading

Semantic preview benefit from parafoveal words is critical for proposals of distributed lexical processing during reading. Semantic preview benefit has been demonstrated for Chinese reading with the boundary paradigm in which unrelated or semantically related previews of a target word N + 1 are replaced by the target word once the eyes cross an invisible boundary located after word N (Yan et al., 2009); for the target word in position N + 2, only identical compared to unrelated-word preview led to shorter fixation times on the target word (Yan et al., in press). A reanalysis of these data reveals that identical and semantic preview benefits depend on preview duration (i.e., the fixation duration on the preboundary word). Identical preview benefit from word N + 1 increased with preview duration. The identical preview benefit was also significant for N + 2, but did not significantly interact with preview duration. The previously reported semantic preview benefit from word N + 1 was mainly due to single- or first-fixation durations following short previews. We discuss implications for notions of serial attention shifts and parallel distributed processing of words during reading.

Shopping in the Public Realm: A Law of Place

Through a case study based in Bristol, this article explores how the ‘law of place’ has transformed multiple heterogeneous city centre spaces into a single homogeneous and commodified privately owned retail site. Drawing on de Certeau, Lefebvre, and humanistic geographers including Tuan, the article explores how law facilitates spatial and temporal enclosure through conventional understandings of private property, relying on techniques of masterplanning, compulsory purchase, and stopping up highways. It suggests that the law of place draws on binary spatial and conceptual distinctions to apparently separate places from spaces, applying different legal rules either side of an often invisible boundary line. The article questions this legally facilitated spatial and conceptual enclosure, particularly as it restricts spatial practices within the public realm. It concludes by rejecting an urban ‘right to roam’ as insufficiently transformative, calling for a broader interpretation of Lefebvre's ‘right to the city’ instead.

Looking across the Hearing Line?: Exploring Young Deaf People’s Use of Web 2.0

Looking across the Hearing Line?: Exploring Young Deaf People’s Use of Web 2.0

La transparencia y la exclusión: ver pero no estar

This paper reflects upon the paradox created by transparency in architecture. The glass plane is a strategy used in modern architecture to delimit a space and at the same time to keep a continuous, instantaneous, and permanent visual relationship with the exterior environment to which it is oriented. However, despite its reflectivity and absolute transparency, the glass plane serves a second paradoxical purpose. The exterior appears actually exposed and configured through the transparent plane, but the integration of interior and exterior is only a simulation. Even though invisible, the boundary is always present. Creating a “continuous” space through an invisible boundary is hence an unattainable objective. The analysis of a scene from the film “The Wings of Desire” (Wenders, 1987) serves as a metaphor clearly showing the duality of the architectural transparency. The film characters are two angels inside a car-dealer showroom, looking at humans walking on the street outside. The showroom is designed to produce total and unobstructed visibility. Even tough everything is set up to allow the characters to encounter and feel visually integrated with the humans outside, they are helplessly apart from them. When observed through the scene, such a relationship – the interaction between people and their environment, promised by the transparency in architecture – results in ambiguity: the glass is never invisible enough to erase the separation for those who are behind it. Key words: transparency, modern architecture, film.

Parafoveal-on-foveal Interactions in Normal Chinese Reading

How much information can be acquired from a single fixation in normal reading-Whether words in a sentence are processed one by one (serially),or two or more words are processed in parallel,is a major dispute between serial attention shift (SAS) and distributed lexical processing models (SWIFT) of eye movement control.Assessing which type of model is more consistent with empirical data has become a hot topic in research examining eye movements during reading.The main purpose of the present study was to determine how processing of characters in the parafovea affects foveal inspection time during Chinese sentence reading.The boundary paradigm (Rayner,1975) was used in two experiments designed to examine whether processing of the fixated character was affected by the frequency of the character to the right of fixation.An invisible boundary was positioned between the two characters (N and N-1).Once the reader's eyes crossed the boundary,the incorrect preview of N was changed to the correct character,ensuring that the preview character was only available for parafoveal processing.In Experiment 1,30 university students were asked to read 48 sentences.There were two types of preview characters (high-or low-frequency),both of which were congruent with the context.When the eyes crossed the invisible boundary,both previews were changed to the same target character,which was also congruent with the context.In Experiment 2,34 university students were asked to read 76 sentences.Again,the frequency of the preview character was manipulated (high or low).Both of the two preview characters were incongruent with the sentence context,but the target character was congruent with the context.In Experiment 1,the results showed that first fixation durations and gaze durations on character n were longer with low-frequency previews than with high-frequent previews.In contrast,first fixation durations and gaze durations on character n-2 were longer in the condition where a high-frequency preview of n was being presented compared to a low-frequency preview.In Experiment 2,there were no significant differences for first fixation durations and gaze durations on character n between high or low frequency preview conditions.However,first fixation durations and gaze durations on character n-2 were longer in the condition where a low-frequency preview of n was being presented compared to a high-frequent preview-the opposite pattern observed in Experiment 1.The results showed that information about character frequency can be accessed in parafoveal preview.Furthermore,this preview information can affect processing of the currently fixated character to some extent (the results showed a strong preview effect but less stable parafoveal-on-foveal effects).The data from these experiments fit better with the theoretical assumptions of parallel processing models of eye movement control in reading.

Whatever You Want? Beyond the Patient in Medical Law

Simon Woods proposes that we ought to re-orientate clinical decisions at the end of life back towards the patient, so as to honour his or her account of their "global" interests. Woods condemns the current medico-legal approach for remaining too closely tethered to the views of doctors. In this response, I trace the story of Mrs Kelly Taylor, who sought to be sedated and have life-sustaining treatment withdrawn, and I do so in order to show not only why Woods is right to detect an asymmetry in the law but also why there is more to the legal landscape than first appears. I argue that patient choice is indeed bounded--most obviously by the views of the doctors (and the judges), but no less significantly by so-called "public interest" concerns. Woods' proposal implicitly, and rightly, forces reconsideration of these public interest dimensions of medico-legal decision-making. This often invisible boundary is not presently granted the attention it deserves (not least by the judges themselves). However, as soon as we delve into the ethical values at stake, then it becomes apparent that there are many more questions to be asked regarding their meaning and interaction before we can determine the appropriate ethical prism through which to view the health care endeavour in English medical law.

Writing Deafness: The Hearing Line in Nineteenth‐Century American Literature by Christopher Krentz

Writing Deafness: The Hearing Line in Nineteenth-Century American Literature Christopher Krentz. Chapel Hill, NC: University of North Carolina Press, 2007. Christopher Krentz in Writing Deafness: The Hearing Line in Nineteenth-Century American Literature looks at deafness in the context of how Americans have formed personal identity. Krentz began to lose his at the age of nine. He found his way to the after college. He learned American Sign Language and came to proudly identify as deaf (xi). Writing Deafness illustrates what he means by this in its explication of how deaf authors and nineteenthcentury American canon authors addressed the hearing line, that invisible boundary separating deaf and (p2). He uses the terminology of hearing line in ways that are similar to W.E.B. DuBois' discussion of the color line. Krentz initially addresses the work of deaf writers who published in the early 180Os: Laurent Clerc (who co-founded the first school for the deaf in the United States with Thomas Hopkins Gallaudet), James Nack (publishing the first book in America by a deaf person), and John R. Burnet (publishing a book on poetry). The work of these authors allowed deaf people to gain more control over their representation, to prove their reason and humanity, and to combat prejudice (26). He emphasizes the struggle of deaf authors to write using the English language slightly differently in order that it had a distinctly deaf tinge that would communicate their unique experience (45). In re-examining some of the canon authors of American in the early nineteenth century, he argues that just as Toni Morrison looked at the national literature from the point of view of how it negotiates racial identity he looks at the works of such authors as Washington Irving and James Fennimore Cooper in terms of how they effectively construct and probe the line (64). Krentz chiefly finds that the authors express both horror and admiration for deaf characters and ultimately associate deafness with unfathomable silence, powerful nonvocal communication, and the vast natural (97). As the nineteenth century progressed, Krentz argues, American writers chiefly employed deaf characters in their works as a way to express their own anxieties and desires and to attempt to demarcate their identities as (100). One example is Lydia Huntley Sigourney, a well-known mid-nineteenth-century poet who wrote on religious themes, expressing horror, condescension, and pity toward deaf characters while at the same time as she esteemed, idealized, and romanticized them. Mark Twain, Ambrose Bierce, Herman Melville, and Sigourney generally incorporated deaf characters in their work as children and women with passive natures. Not developing fully realized adult characters, canon authors objectified the deaf and were never quite able to humanize deaf characters. But, Krentz argues they at least attacked the old notion that deafness is a mark of evil and raised consciousness of deaf people in mainstream (129). Deaf authors writing in English expressed concerns about how the deaf experienced a persistent sense of two-ness in their efforts to live in American society. They took pride in a deaf community that was able to build and grow schools and associations, support heroic figures who represented the community, and develop American sign language. At the same time, deaf authors expressed the difficulties of living in a world and not being able to withstand feelings of inferiority and marginalization (139). Deaf authors suggested a variety of directions that the deaf could take to achieve the best possible outcomes for the community in American society. Laurent Clerc argued that segregated deaf schools were the best strategy. John Jacobs Flournoy argued that deaf people should separate from the larger American society by forming their communities in a state or territory that would provide complete segregation until society was more just and accessible (156). …

The fuzzy-boundary arena—A method for constraining an animal's range in spatial experiments without using walls

A method is described for confining an animal within an experimenter-defined area without the use of physical boundaries. The area of exploration is constrained by the presence of an aversive noise, triggered whenever the animal steps across a computer-controlled boundary. The radius of the invisible boundary is constantly reset so that the boundary becomes “fuzzy” and the animal cannot use it as a spatial localizing cue. The effectiveness of this technique is demonstrated both with behavioural data confirming reliable confinement, and also recordings of hippocampal place cells made from rats exploring the arena. The place cell data reveal that indeed, the cells did not appear to be controlled by the fuzzy boundary, in contrast with the strong control normally exerted by fixed boundaries. This technique is thus promising for studies of spatial behaviour in which the strong influence of walls needs to be removed in order to allow the study of more subtle processes such as landmark use and path integration.

Boundary Conditions in Particle Swarm Optimization Revisited

In order to enforce particles to search inside the solution space of interest during the optimization procedure, various boundary conditions are currently used in particle swarm optimization (PSO) algorithms. The performances, however, vary considerably with the dimensionality of the problem and the location of the global optimum in the solution space. In this paper, different boundary conditions are categorized into two groups, namely, restricted and unrestricted, according to whether the errant particles are relocated inside the allowable solution space or not. Moreover, efforts are made to explore different hybrid unrestricted boundary conditions by introducing the favorable characteristics of the reflecting and damping boundary conditions into the existing invisible boundary condition. The performances of the boundary conditions are tested based on both mathematical benchmark functions and a real-world electromagnetic problem: the optimization of a 2-D 16-element array antenna. Simulation results are examined from both the effectiveness and efficiency of the algorithm. Comparisons show that the unrestricted boundary conditions are more efficient when the global optimum is inside the boundary of the solution space, and the damping boundary condition is more robust and consistent when the global optimum is close to the boundary

Eye Movements and Phonological Parafoveal Preview: Effects of Reading Skill.

Eye movements of skilled and less skilled readers were monitored as they read sentences containing a target word. The boundary paradigm was used such that when their eyes crossed an invisible boundary location, a preview word changed to the target word. The preview could either be identical to the target word (beach as a preview for beach), a homophone of the target word (beech as a preview for beach), an orthographic control (bench as a preview for beach), or an unrelated consonant string (jfzrp as a preview for beach). Consistent with prior research, skilled readers obtained more preview benefit from the homophone preview than from the orthographic preview. The less skilled readers, however, did not show such an effect. The results indicate that less skilled readers do not use phonological codes to integrate information across eye movements. Indeed, the results also indicate that less skilled readers do not show normal preview benefit effects.

Are long compound words identified serially via their constituents? Evidence from an eye-movement-contingent display change study.

The processing of two-constituent 12- to 18-letter Finnish compound nouns was studied by using an eye-movement-contingent display change technique. In the display change condition, all but the first 2 letters of the second constituent were replaced by visually similar letters until the eyes moved across an invisible boundary. When the eyes crossed the boundary, the second constituent was changed to its intended form. In the control condition, there was no display change. The frequency of the first constituent was also varied. The major findings were that (1) fixation time on the first constituent was strongly affected by the frequency of the first constituent but was not at all affected by whether the second constituent was visible, but (2) fixation time on the word subsequent to the first constituent's having been left was strongly affected by the display change. These results are most parsimoniously explained by the serial access of the two constituents for these long compound words.

Life on the Margins of a Florida Retirement Community: The Experience of Snowbirds, Newcomers, and Widowed Persons

This article adds to research on retirement communities, which has primarily looked at them at one stage in their development and assumed that a homogeneous population as a background variable contributes to high levels of social integration and a strong sense of community. It presents the situation of three groups who live in a 10-year-old Florida retirement community—snowbirds, newcomers, and widows and widowers. Members of these three groups live on the social margins of the community. The article examines both the structures within the community and the social processes that create an invisible boundary that puts marginal residents on the outside. It concludes that increasing diversity is inevitable and that homogeneity or lack thereof is in the eye of the beholder. Findings are based on participant observation and in-depth interviews.

Now Voyager

Deep in space, more than 20 years after its launch on September 5, 1977, and long after most people have forgotten about it, Voyager I will take over the mantle as the most distant human‐made object in the solar system on February 15, according to the Jet Propulsion Laboratory (JPL). Somewhere beyond 10 billion km from Earth, the spacecraft finally will outdistance Pioneer 10.Voyager I, racing through the solar system at 17.4 km/s, is expected to reach another milestone in about the year 2003, when it passes through the “termination shock” on its way to the heliopause. That invisible boundary separates our solar system from interstellar space and marks the outermost edge of the Sun's magnetic field.

Off Cue: Women who play pool

Pool halls in Australia, as in most English-speaking coun tries, are largely male preserves, and most pool players aremen. This paper explores some of the factors underlying why comparatively few women play pool, and what happens to those women who do breach the invisible boundary thatmarks off the pool halls as male territory. Using observations and interviews conducted in an Australian university union bar, this study suggest that pool playing serves to confirm certain forms of masculinity. Sexual harassment and other forms of intimidating behaviour are used to exclude women from playing pool. Furthermore, those women who are admitted to pool playing are accepted on terms (such as having a male sponsor) that minimise the intrusion and pre serve male power and control over the space.

Peculiarities of the quantum interchannel motion: Why the quantum lattice wave does not slide down the potential slope

Unlike classical and quantum particles rolling down a potential slope, quantum waves on a lattice are confined in bound states on the potential hill. For the linear potential there is an equidistant spectrum of these states. The well-known Bessel functions ${\mathit{J}}_{\mathrm{\ensuremath{\alpha}}}$(kr) with the integer index \ensuremath{\alpha} as a discrete spatial coordinate (not r as usual) play the part of the bound-state wave functions---standing waves between the potential hill and the invisible boundary of the upper forbidden zone. This exactly solvable model elucidates some peculiar features of more realistic systems, particularly, the interchannel wave motion where \ensuremath{\alpha} means the discrete channel number.

Segmental lineage restrictions in the chick embryo spinal cord depend on the adjacent somites

We have investigated whether the developing spinal cord is intrinsically segmented in its rostrocaudal (anteroposterior) axis by mapping the spread of clones derived from single labelled cells within the neural tube of the chick embryo. A single cell in the ventrolateral neural tube of the trunk was marked in situ with the fluorescent tracer lysinated rhodamine dextran (LRD) and its descendants located after two days of further incubation. We find that clones derived from cells labelled before overt segmentation of the adjacent mesoderm do not respect any boundaries within the neural tube. Those derived from cells marked after mesodermal segmentation, however, never cross an invisible boundary aligned with the middle of each somite, and tend to be elongated along the mediolateral axis of the neural tube. When the somite pattern is surgically disturbed, neighbouring clones derived from neuroectodermal cells labelled after somite formation behave like clones derived from younger cells: they no longer respect any boundaries, and are not elongated mediolaterally. These results indicate that periodic lineage restrictions do exist in the developing spinal cord of the chick embryo, but their maintenance requires the presence of the adjacent somite mesoderm.

Spectral lines: Enlarging the circle

A few years back we wrote about individuals' ?circles of concern,? suggesting that each human being is surrounded by an invisible boundary that defines his or her interests. The circles may be small or large.

High-pressure phase equilibria for the methanol-ethylene system at 25.DEG.C and 40.DEG.C.

Isothermal phase equilibria for the system methanol-ethylene were measured at 25°C and 40°C by a static method. At each temperature, an invisible boundary in a high-pressure equilibrium region was found by gas chromatographic analysis. For studying the phase behavior of the methanol-ethylene system, the critical loci for the system were estimated by using the Soave-Redlich-Kwong equation of state. The calculation shows that an isothermal phase equilibrium of the methanol-ethylene system exhibits one to three critical points.