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PubMed2001

How close is too close? A comparison of proxemic reactions of Singaporean Chinese to male intruders of four ethnicities.

Cultural and ethnic influence on proxemic behavior and invasions of personal space were investigated. 173 Chinese Singaporean undergraduates rated minimum interpersonal distance for perceived male intruders from four ethnic groups in Singapore--Malay, Indian, Chinese, and Caucasian. Rated distance scores ranked from "most distant" Indian Chinese dyads decreasing (in order of minimum distance) through Malay-Chinese. Caucasian-Chinese, and Chinese-Chinese dyads, independent of sex.

Adult↗
PubMed2002

Horizontal-vertical illusion: continuous decrement or the deviant first guess?

Numerous studies have reported that repetitive or extensive inspection leads to short-term decrement of the horizontal-vertical illusion. The present experiment explored whether this decrement reflects a gradual decline, as previously assumed, or is better described as a singular drop-off beyond the initial evaluation. 111 student participants adjusted vertical or horizontal lines such that they appeared equally long with a perpendicular standard. There were 8 successive adjustment trials for each subject. The results suggest that a substantial component of the illusion depends on the first impression assessment. The earlier anatomical and cognitive theories of the horizontal-vertical illusion cannot incorporate this datum. However, recent findings suggest that a motor theory of illusion might accommodate the observed one-step decrement in the illusion.

Adult↗
PubMed2002

Rehearsal of task variations and contextual interference effect in a field setting.

The present study showed a consistent pattern with a typical contextual interference effect in motor skill learning (N=38 adults). Individuals trained under the high contextual interference condition may receive greater learning benefits than those under the low contextual interference condition during the rehearsal of task variations of a single motor skill in a field setting.

Adolescent↗
PubMed2002

Velocity, occlusion, and sex of subjects in coincidence of anticipation.

The purpose of this study was to assess effects of velocity, occlusion distance, and sex on coincidence of anticipation. The Bassin anticipation timer was used to test 25 men and 25 women when velocity was .69 m/sec. and 1.38 m/sec. or "slow" and "fast", and occlusion distances of zero, 1.06 m and 2.12 m were "zero," "small," and "large" on a 4.25-m length of track. There were six test conditions. Analysis showed that increased occlusion distances produced increased absolute, constant, and variable error scores. A significant interaction of velocity and occlusion appeared for all error measures. With an increase in occlusion distance at the slow velocity constant error increased in the positive direction or early response while at the fast velocity a similar increase in constant errors was seen but in the negative direction or late response. Under zero occlusion the expectation that performance at the fast velocity would be more accurate and show less variability than at the slow velocity was not supported. Also, sex did not significantly affect anticipation time in any condition or on any error measures.

Acceleration↗
PubMed2002

Viewing distance and estimates of duration.

28 students reproduced the durations of 12- and 18-sec. intervals, which were defined by a moving stimulus on a computer monitor. The monitor was viewed from a distance of either .4 or 2.5 m. Temporal reproductions were significantly greater for the far than for the near distance conditions. Results are considered from the perspective of the change models of timing.

Distance Perception↗
PubMed2002

Differences in kata performance time and distance from a marker for experienced Shotokan karateka under normal sighted and blindfolded conditions.

10 experienced Shotokan karateka were tested on performance time and distance from a marker on the five Heian kata under normal sighted and blind-folded conditions. Whilst each kata's line of movement is different, it is the intention to start and finish at the same location. Analysis showed that despite an average of 16.8 yr. of training, whilst timing was not significantly affected on four of the kata by subjects being deprived of the visual sense, the group's mean change in distance from an original marker was significant for performances on three of the kata.

Adult↗
PubMed2002

Observation distance and recognition of photographs of celebrities' faces.

Subjects were tested to assess the distance at which they could recognize the faces of celebrities (more specifically, a set of 44 portrait photographs of movie and television actors). The set of test photographs was shown initially at a distance of 200 ft. and then closer in increments of 20 ft. When the actor in a given photograph was identified, either by name, character role, or by the movie or television show in which the actor had starred, the recognition-distance was recorded and the photograph was removed from the test set. Those which were not recognized (even at the closest distance) were not included in the data summaries or statistical analysis. In calculating recognition-distance for each photograph, the values were adjusted to reflect the distance at which recognition would have occurred if all the faces were of normal size. The upper limit for recognition, as defined by the distance above which only 10% of the faces are identified, was just over 160 ft. for women, and just under 200 ft. for men. There was also a significant difference in mean recognition distance between women and men. The large range of recognition-distance (across photographs and across subjects) argues that the distance is not controlled primarily by the feature detail provided in a given photograph or by the discrimination and recall skills of the observer. More likely it is a function of diverse memory associations, so that the distance at which each photograph is recognized will depend on such factors as frequency and recency of exposure, perceived attractiveness, and how much the subject admires the celebrity.

Adult↗
PubMed2002

Do landmarks help or hinder women in route learning?

Previous research on route learning has demonstrated that men learn routes faster and with fewer errors than women, whereas women are able to recall more landmarks along the route. The present study was aimed at investigating whether landmarks help or hinder women when they learn a route. 47 female and 37 male undergraduate students were randomly assigned to one of two conditions, in which they learned a route on a map with landmarks (the Landmark condition) or with no landmarks (the No-Landmark condition). Men outperformed women in the Landmark condition, learning the route in less time, with fewer errors, and in fewer trials than women did. In contrast, in the No-Landmark condition, no significant differences were found between men and women on the route-learning measures. Men learned the route faster and more accurately when landmarks were present than when they were not, but the performance of women was not affected by the presence or absence of landmarks. These results suggest that men and women may employ landmarks differently when learning a route. Men may use the positions of landmarks to make distance and direction judgments, whereas women may label the landmarks and memorize these labels, which interferes with learning the route.

Adult↗
PubMed2002

Influence of stimulus distance in implicit learning of spatial and nonspatial event sequences.

The serial reaction time task has been widely used to investigate implicit learning mechanisms. In the present study, we investigated the effect of stimulus distance on learning of a spatial sequence independent of a sequence of responses. Participants had to respond to objects appearing at four different locations. The objects were presented in a sequence of nine elements, whereas the location at which an object was presented followed a sequence of eight elements. Thus, the spatial and the object sequences were independent of each other. Four groups of subjects for whom the distances of the locations chosen to present objects on the computer screen (3 cm, 6 cm, 12 cm, or 22 cm) differed were tested. Only the nonspatial sequence was learned as indicated by enhanced response latencies in nonsequenced random blocks. Stimulus distance had no effect on the amount of sequence learning. Additional analyses for subgroups of subjects who did not show explicit knowledge of the sequences after completion of the task indicated that for implicit learners also, sequence learning was not influenced by stimulus distance. The results are discussed with respect to current theories of implicit serial learning.

Adolescent↗
PubMed2003

Sex differences in landmark learning by children aged 5 to 12 years.

Previous research has shown that men and boys learn routes faster and with fewer errors than do women and girls. Research with adults suggests that men use Euclidean cues when learning a route, whereas women use landmark-based strategies. The strategies used by children have received little study. In Exp. 1, 50 boys and girls, ages 5 to 12 years, were shown a map that contained only landmarks (no streets or roads) and were asked to learn a route consisting of 23 of the landmarks. The children used a pointer to trace the route on the map to a criterion of two successive trials without errors. The performance of boys and girls did not differ significantly on this route-learning task on three measures (number of trials to reach criterion, total time to reach criterion, and total number of errors). In Exp. 2, 52 boys and girls, ages 5 to 12 years, were shown the same map as in Exp. 1 and were asked to learn a route consisting of 12 landmarks. The children traced the route by picking pictures of landmarks in the correct order from a stack of cards with pictures of landmarks on them. Girls made significantly fewer errors than boys on this route-learning task in Exp. 2, and a significantly larger number of girls than boys completed the task. None of the boys in the 5- to 6-yr.-old age group learned the route. When Euclidean cues were minimized in Exp. 2, boys made more errors and took as much time as girls to reach the criterion of two successive correct trials.

Child↗
PubMed2004

Effect of deception of distance on prolonged cycling performance.

This study examined the effect of deception of distance end-point on prolonged cycling performance. 21 subjects were randomly allocated to three groups (n = 7 per group). Each group completed three self-paced time-trials separated by one day. Subjects were told that each trial was a 30-km time-trial and were required to complete the distance in the fastest time possible. Following the initial trial of 30 km, one group completed Trial 2 with a longer distance (long distance group; 36 km), another group with a shorter distance (24 km; short distance group), and the third group as control (30 km; control). Each group then completed a third time-trial of 30 km. At no time was the deception of distance in Trial 2 disclosed to the subjects, and all sources of physiological and mechanical feedback were withheld during the trials. Data from Trials 1 and 3 were analysed by repeated-measures analysis of covariance. Time to complete Trial 1 was similar among groups (approximately 65 min.). Following the deception in Trial 2 the time to complete the 30 km in Trial 3 was increased for the short distance group, decreased for the long distance group, whilst the time for the control group remained unchanged. The times to complete the 30 km on Trials 1 and 3 were matched by changes in power output throughout the trials. It is concluded that subjects deceived of the actual distance completed will complete the subsequent performance trial based on perceived effort rather than on actual distance.

Adult↗
PubMed2002

Judgments about length, weight, and width covariation as a function of intelligence and depth of processing in elementary school children: a preliminary study.

28 elementary school students were assessed for intelligence, then blindfolded and asked to explore objects manually before rendering judgments about how weight and width were related to length. Exploration time for each object was hypothesized to reflect the level of processing engaged in by the participants. It was also predicted that more intelligent children would produce the most accurate judgments. Inconsistent with the predictions, analysis indicated that children of higher intelligence did not produce the most accurate judgments. However, longer exploration times reflected a tendency to refrain from endorsing a negative correlation between length and width. Depth of processing is, therefore, presumed to aid in reasoning about covariation.

Child↗
PubMedDate not supplied

The mechanism of physiological height vertigo. I. Theoretical approach and psychophysics.

A theory is presented supporting a geometrical explanation of physiological height vertigo as a 'distance vertigo' created by visual destabilization of posture when the distance between the observer and visible stationary contrasts becomes critically large. Though height vertigo is generally regarded as a psychopathological process, we hypothesize that it might instead result from an intersensory mismatch when visual information is at variance with vestibular and proprioceptive inputs. Psychophysical experiments confirming the hypothesis revealed that: 1) height vertigo is clearly related to body position, being the greatest in the upright stance; 2) it is the eye-object distance rather than the direction of gaze which is critical; 3) there is a saturation of height vertigo magnitude. Subjective vertigo increases with increasing altitude only below 20 metres. Physiological 'distance vertigo' must be distinguished from psychological 'acrophobia'. Its postural consequences may be ameliorated by strategies gleaned from knowledge of its mechanism such as providing nearby stationary contrasts in the peripheral visual field.

Adult↗
PubMedDate not supplied

The mechanism of physiological height vertigo. II. Posturography.

In order to validate the hypothesis that height vertigo is based on visual destabilization of free stance when the distance between eye and object becomes critically large, several of its consequences were demonstrated in posturographic experiments: (1) Visual signals conflicting with simultaneous vestibular and somatosensory inputs provided by sinusoidally tilting rooms may destabilize postural sway in the fore-aft as well as in the lateral direction. (2) In natural surrounding sway amplitudes increase with increasing eye-object distance up to 5 meters. Thus, teleologically, subjective height vertigo serves as an appropriate warning signal to withdraw the body from a stimulus situation inducing postural imbalance. (3) Postural height vertigo problems can be alleviated (a) by adjusting the head relative to the gravitational vector, and (b) by the presence of nearby stationary contrasts in the visual periphery according to the dominance of retinal periphery for dynamic spatial orientation.

Adult↗
PubMed1995

Influence of target distance and acceleration level on eye movements evoked by lateral acceleration steps.

Lateral eye movements produced by linear acceleration along the inter-aural axis were studied in 6 normal subjects. They were seated upright, whole-body restrained, and were exposed to randomised rightward/leftward steps of 0.05 g. 0.1 g, 0.24 g of 600 ms duration. When viewing earth-fixed targets at 30, 60 or 280 cm from their eyes, mainly pure compensatory slow-phase eye movements were evoked at latencies around 50 ms measured for the closest viewing distances. At onset, slow-phase amplitude was modulated by acceleration and target distance. When the subjects were stationary and pursued moving targets at similar distances and accelerations, latencies around 140 ms were observed, and catch-up saccades were frequently made. From these experiments, we defined the dynamics of the otolith-ocular reflex for various levels of acceleration and viewing distances.

Adult↗
PubMed1983

Recent advances in clinical low-vision care.

In the past decade there has been a growth in the awareness of the impact that low vision has on the individual and on society in general. The clinical eye-care professions have become more conscious of their responsibility to assist partially sighted patients and low-vision care is becoming a specialty area within optometry and ophthalmology. This paper reviews recent advances in the optical devices and prescribing procedures that have contributed to improving the care that is available to assist low-vision patients with distance-vision tasks, near-vision tasks and visual-field problems.

Distance Perception↗
PubMed2004

Cross- and within-cultural variations in children's understanding of distance, time, and speed interrelationships: a follow-up study.

A problem with interpretations of differences in mathematic achievement between students from Asian countries and those from the United States is the seemingly implicit assumption of the cultural homogeneity of Asian societies. Researchers rarely measure the effects of variables within cultures that are hypothesized to be related to differences across cultures. In the present study, the authors examined the effects of socioeconomic status (SES) and quality of instruction on Chinese students' (1st, 3rd, and 5th grades) understanding of distance, time, and speed. The results indicated that (a) low SES in China can impede the development of children's mathematical cognition and (b) higher SES does not guarantee better performance. The implication is that the gap in mathematical performance between socioeconomically advantaged and disadvantaged children can be narrowed or even eliminated through instructional practices that focus on the systematic training of children's mathematical thinking.

Child↗