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At least 1,711 records · Page 95Linked to original sources
PubMed2002

Separate sources of spatial information for distance and location in rapid aiming movements.

The purpose of this research was to examine the role of distance and location information in the production of rapid aiming movements. Participants performed an aiming task consisting of horizontal left-handed elbow flexion movements that translated to movements of a cursor on an oscilloscope screen. The location of the home position and the target on the oscilloscope screen were fixed but the initial angle of the elbow was varied randomly. Participants were informed that the required distance was always constant. Initial impulse and error correction phases were analyzed to examine whether separate spatial codes for distance and position were used in the control of these two movement phases. The results indicated that initial impulse endpoints and the final positions of the limb overshot the target from the leftmost starting positions, while they undershot the target from the rightmost starting positions. Also, varying the initial angle of the elbow had a greater influence on the final position of the limb than initial impulse endpoints.

Biomechanical Phenomena↗
PubMed2006

Neural correlates of the dependence of compensatory eye movements during translation on target distance and eccentricity.

To stabilize objects of interest on the fovea during translation, vestibular-driven compensatory eye movements [translational vestibulo-ocular reflex (TVOR)] must scale with both target distance and eccentricity. To identify the neural correlates of these properties, we recorded from different groups of eye movement-sensitive neurons in the prepositus hypoglossi and vestibular nuclei of macaque monkeys during lateral and fore-aft displacements. All neuron types exhibited some increase in modulation amplitude as a function of target distance during high-frequency (4 Hz) lateral motion in darkness, with slopes that were correlated with the cell's pursuit gain, but not eye position sensitivity. Vergence angle dependence was largest for burst-tonic (BT) and contralateral eye-head (EH) neurons and smallest for ipsilateral EH and position-vestibular-pause (PVP) cells. On the other hand, the EH and PVP neurons with ipsilateral eye movement preferences exhibited the largest vergence-independent responses, which would be inappropriate to drive the TVOR. In addition to target distance, the TVOR also scales with target eccentricity, as evidenced during fore-aft motion, where eye velocity amplitude exhibits a "V-shaped " dependence and phase shifts 180 degrees for right versus left eye positions. Both the modulation amplitude and phase of BT and contralateral EH cells scaled with eye position, similar to the evoked eye movements during fore-aft motion. In contrast, the response modulation of ipsilateral EH and PVP cells during fore-aft motion was characterized by neither the V-shaped scaling nor the phase reversal. These results show that distinct premotor cell types carry neural signals that are appropriately scaled by vergence angle and eye position to generate the geometrically appropriate compensatory eye movements in the translational vestibulo-ocular reflex.

Accommodation, Ocular↗
PubMed1990

Visibility distance of highway signs among young, middle-aged, and older observers: icons are better than text.

The visibility distances for young, middle-aged, and elderly observers of text and icon versions of four different highway signs were compared under day and dusk lighting conditions. No age differences were observed. Icon signs, however, were visible at much greater distances than were text signs for all three age groups, a difference that was more pronounced under dusk conditions. There were no age differences in the comprehension of icon signs, but there was considerable variability from one icon sign to another in the degree to which they were comprehended. Acuity was found to be a better predictor of the visibility distance of text signs in both day and dusk conditions than it was of icon signs. To the degree that they are comprehended, icon signs appear to offer drivers of all ages almost twice as much time in which to respond to them.

Adult↗
PubMed1992

Distance and organization in multifunction displays.

One approach to organizing information in a multifunction display (MFD) is to place related screens of information closer to each other. This study identified three metrics that could be used to operationalize the concept of distance in an MFD. The proposed distance metrics-navigational (the number of choice points lying between two screens), organizational (the hierarchical structure of the data base), and the cognitive (the user's perception of relationships among screens)-were empirically examined by using a simulated, hierarchically arranged, menu-driven MFD in an aviation context. Subjects engaged in two tasks that required them to access different target screens from various starting screens in a 290-screen MFD. The tasks differed in the navigational mechanisms subjects were allowed to use to navigate around the MFD and the relationships between the starting and target screens. The results suggest that the three distance metrics are meaningful within the context of a multifunction display.

Adult↗
PubMed2006

Distance learning for communicating cancer, culture, and literacy: a model for cancer control advancement.

BACKGROUND: Successful cancer control communications and research must reflect an understanding and appreciation of the importance of cultural, linguistic, and literacy needs of diverse audiences. The Cancer, Culture and Literacy Institute, a National Cancer Institute-funded R25 educational project, blends traditional learning approaches with distance learning methodologies to reach demographically dispersed cancer control researchers with new knowledge and skills on culture and literacy. We report here the distance learning component of the project. METHODS: A Web-based learning management system was developed that consisted of three elements: (1) educational modules, (2) communications, and (3) resources. RESULTS: Results from 64 doctorally prepared participants demonstrated high satisfaction with the content, high usefulness of materials, and very good to excellent stimulation of thinking. CONCLUSIONS: Distance learning offers a promising and appealing vehicle for communicating cancer control skills, interventions, and best practices, and thus has the potential to impact the appropriateness of cancer communications, research, and education.

Computer-Assisted Instruction↗
PubMed2004

Overview of geriatric distance education for academic courses and continuing education.

Distance education technologies may be applied to academic settings, continuing education/continuing medical education settings or in combination to both. This article provides an overview of what we have learned about academic and continuing education/continuing medical education in geriatrics and gerontology. It includes information on the scope of distance education, the strengths and challenges of distance education, and discusses issues related to technology, intellectual property, instructional design and curriculum development, collaborative effort, marketing, evaluation, and research.

Certification↗
PubMed2005

Delivering distance training to rural health care professionals.

This article reports on a project that delivers distance training to rural health care professionals. Traveling to provide training on information-seeking skills to rural health professionals is time consuming and costly. In addition to face-to-face training, the University of South Alabama Biomedical Library's SAMNet project seeks to deliver multimedia training to rural health care professionals. The project uses information technology to package training courses combining PowerPoint slides and video instructions. This article describes the rationale, training module design and development, and the information technology and software used in the project. Multimedia packaged distance training courses provide a practical alternative to on-site training for rural health care professionals. It enables librarians to provide training without traveling long distance, thus saving time and money. Additionally, rural health care professionals may access the modules at a time convenient to them and proceed at a pace suitable to their learning style.

Academic Medical Centers↗
PubMed2006

Let's reach all of the market for health administration education: design, development, and delivery issues in distance delivery.

Web-based distance learning is an up and coming form of education. Web-based education delivered via a Web browser through the Internet has been found to be less expensive, more efficient, and sometimes more effective than classroom training. In the distance learning environment, the traditional "lecture and chalkboard" classroom pedagogy is completely absent. The virtual classroom becomes an "active learning" environment in which students, while utilizing technology, are able to discuss health administration concepts, analyze cases, work exercises, and discuss and share these interactively with both the instructor and fellow classmates. This method of Health Administration Education encourages students to learn from each other and promotes the open exchange of ideas and experiences. It does not require working students to put their careers on hold while they continue their studies. In this paper, we explore the opportunities and challenges of delivering web-based Health Administration courses via the Internet. Included is a discussion of the design, development, and delivery of a distance learning, web-based Health Administration Education system.

Adult↗
PubMed2004

False consensus in social context: differential projection and perceived social distance.

The study implicates the notion of perceived social distance as an explanation of why ingroup false consensus exceeds outgroup false consensus. Whilst previous demonstrations are best understood from social identity perspectives, the findings reported here suggest that self-group as well as inter-group comparisons can underlie such effects. In particular, perceived social distance was shown to mediate the effect of social categorisation: ingroup false consensus was greater because more social distance was perceived with the outgroup. The findings also extended to non-student samples and generalised across both opinion and ability items. In addition, examining the effect of item type in conjunction with social categorisation seriously challenged the generality of the false consensus effect.

Adult↗
PubMed1985

Distance perception with holographically reconstructed objects.

It has been assumed that a holographically reconstructed object is seen as though it is the actual object, including that it is seen at the distance of the actual object when it was holographed. A psychophysical experiment was carried out with seven subjects to test this assumption. The results clearly show that the perceived distances of holographically reconstructed objects are not equivalent to the perceived distances of actual objects. Thus a fundamental assumption in holography has not been supported by experimental data.

Distance Perception↗
PubMed2005

Improving access to services and interactions with clients in Guatemala: the value of distance learning.

OBJECTIVE: To develop and test a distance-learning programme to improve the quality and efficiency of family planning services in Guatemala. METHODS: The setting was rural family planning services in Guatemala. The study design was quasi-experimental with one intervention and one control group and with pre- and post-intervention measures. Two staff members from each of 20 randomly selected health districts were trained as leaders of the training programme. In turn, the 40 trainers trained a total of 240 service providers, under the supervision of four health area facilitators. The results were compared with 20 randomly selected control health districts. The intervention was a distance-learning programme including 40 in-class hours followed by 120 inservice practice hours spread over a 4-month period. Distinctively, the programme used a cascade approach to training, intensive supervision, and close monitoring and evaluation. Patient flow analysis was used to determine number of contacts, waiting times, and the interaction time between service providers and clients. Consultation observations were used to assess the quality and completeness of reproductive health information and services received by clients. RESULTS: The intervention showed a positive impact on reducing the number of contacts before the consultation and client waiting times. More complete services and better quality services were provided at intervention clinics. Some, but not all, of the study objectives were attained. The long-term impact of the intervention is as yet unknown. CONCLUSION: Distance-learning programmes are an effective methodology for training health professionals in rural areas.

Community Health Workers↗
PubMed2000

Effects of traditional classroom and distance continuing education: a theory-driven evaluation of a vaccine-preventable diseases course.

OBJECTIVES: This study evaluated the effects of a major federal immunization continuing education course, delivered in both traditional classroom and satellite broadcast versions, on public health professionals' knowledge, agreement, self-efficacy, and adherence in practice to recommendations. METHODS: The study used a comparative time series design to determine whether the course influenced participants' knowledge, agreement, self-efficacy, and adherence in practice to general and polio-specific recommendations as measured immediately and 3 months after the course. It also compared the effects of the classroom and satellite broadcast versions and used path analysis to show how the outcomes were related to one another. RESULTS: Both versions significantly improved knowledge, agreement, self-efficacy, and adherence. Knowledge and agreement were significant predictors of self-efficacy, which directly predicted adherence. Vaccine availability and supportive clinic policies were also important adherence predictors. CONCLUSIONS: A well-designed training update can change provider knowledge, agreement, self-efficacy, and adherence. Traditional classroom and distance training can have comparable effects. The findings support incorporation of distance learning in national public health training, if the distance learning is used wisely in relation to training needs, goals, and practice contexts.

Analysis of Variance↗
PubMed1983

Scaling apparent distance in a large open field: some new data.

Judged distance in a large open field, scaled by the method of magnitude estimation, is related to physical distance by a power function with an exponent smaller than unity. The exponents obtained with two ranges of distance were not affected by the availability of a standard. The mean exponent for all 80 individual power functions was 0.86, with a standard deviation of 0.11.

Adolescent↗
PubMed1991

Preferred sound intensity increase for sensation of half distance.

Two experiments are reported that examine the preferred increase in intensity for creating a percept of half auditory distance from a reference. The results of both experiments indicate that the use of an inverse square law (increments of 6 dB) is not the best signal-processing method for this purpose. The application of the results is potentially useful towards the software design of 3-D auditory display systems that manipulate the perceived distance of auditory inputs in relationships to actual distances of physical objects.

Adult↗
PubMed1991

Differences in interpersonal distance among nonoffenders as a function of perceived violence of offenders.

A group of 39 female and 15 male undergraduate students took part in a study of the relationship between perceived violence of criminal offenders and interpersonal distance preferred by nonoffenders. Preferred interpersonal distance, measured for subjects informed that the person with whom they would be sitting in a room was either a violent offender, nonviolent offender, or nonoffender, was the number of seats subjects chose to sit from the person. Analysis of variance shows subjects preferred significantly less mean distance in the nonoffender condition versus either the nonviolent or violent offender conditions.

Adolescent↗
PubMed1995

On the focal distance of the eye during sighting in pistol shooting.

We measured the focal distance and pupil diameter on the eyes of 11 marksmen sighting a pistol target at 23 m distance. Both upon the focal distance and pupil diameter of the subjects, we estimated the point at which they were looking during sighting. Calculation based on depth of field which can be divided from the pupil diameter of 4.5 mm suggested that the subjects were looking at the foresight of the pistol approximately 80 cm in front of the eye during sighting.

Adult↗
PubMed1999

Shadows as sources of cues for distance of shadow-casting objects.

Shadows are neglected sources of information about shadow-casting objects' distance (location). In an experiment using real shadows, participants judged the distance of two rods, either with shadows (illumination from the left) or without shadows. Without shadows, a thin rod raised slightly above the surface was incorrectly judged to be more distant than a thick rod, but with shadows the thin rod was accurately judged to be closer. For judgments to be correct, shadows had to overwhelm competing height and stimulus-size cues. Exp. II involved nonoverlapping shadows produced by a light placed in front of the rods. Again, without shadows the thin-elevated rod was incorrectly judged to be more distant, but with shadows it was correctly judged to be closer. Exp. III involved two sets of thick and thin elevated rods and frontal lighting. Judgments were accurate when shadows were present but inaccurate when shadows were absent. Experiments conducted through the American Psychological Society Web-research site replicated results of Exp. I, II, and III. A final Web experiment replicated results of the others, but with shadows produced by illumination from the right. Three properties of shadows--angles, interposition, and positioning--are possible sources of distance information associated with cast shadows.

Cues↗
PubMed2001

The Poggendorff illusion: effect of distance between the parallel lines.

43 subjects observed Poggendorff figures with transverse line segments at a constant distance while the parallels were positioned closer or farther apart. At closer distances, no illusion occurred; at farther distances, the illusion diminished. The illusion no longer occurred when the parallels were located beyond the outside end of the transverse lines. Since illusions occurred only when the parallels physically touched the transverse line, this research emphasizes the importance of the intersection of figural elements in the production of the Poggendorff illusion.

Cues↗