Sex and age modulate the visual perception of distance

An experiment was conducted to evaluate the ability of 28 younger and older adults to visually bisect distances in depth both indoors and outdoors; half of the observers were male and half were female. Observers viewed 15-m and 30-m distance extents in four different environmental settings (two outdoor grassy fields and an indoor hallway and atrium) and were required to adjust the position of a marker to place it at the midpoint of each stimulus distance interval. Overall, the observers’ judgments were more accurate indoors than outdoors. In outdoor environments, many individual observers exhibited perceptual compression of farther distances (e.g., these observers placed the marker closer than the actual physical midpoints of the stimulus distance intervals). There were significant modulatory effects of both age and sex upon the accuracy and precision of the observers’ judgments. The judgments of the male observers were more accurate than those of the female observers and they were less influenced by environmental context. In addition, the accuracies of the younger observers’ judgments were less influenced by context than those of the older observers. With regard to the precision of the observers’ judgments, the older females exhibited much more variability across repeated judgments than the other groups of observers (younger males, younger females, and older males). The results of our study demonstrate that age and sex are important variables that significantly affect the visual perception of distance.     

Validity and reliability of a radio positioning system for tracking athletes in indoor and outdoor team sports

Radio-frequency local positioning systems (LPS) have the potential to provide accurate location information about sport players for performance analysis, making available for study the emergent nature of interpersonal coordination and collective decision-making behaviour among players in both indoor and outdoor sports. However, no available publications have validated the performance of LPS for indoor sports. The objective of this study was to validate the performance of an LPS in an indoor venue and to compare it to performance observed in an outdoor venue using static and dynamic measurements. Our results showed that the absolute positioning errors obtained from the static measurements of the LPS were comparable for both indoor and outdoor venues, with mean errors of 12.1?cm outdoors and 11.9?cm indoors. From the dynamic measurements, we analysed the relative position error and the distance estimation performance of the system. The 90th-percentile relative position errors were 28?cm for the indoor venue versus 18?cm for the outdoor venue. On average, the LPS overestimated the distance travelled, and the performance was similar for both indoor and outdoor venues. On a linear course, the mean errors of the distance estimates were 2.2% of the total distance indoors and 1.3% outdoors, and on a nonlinear course, they were 2.7% indoors and 3.2% outdoors.     

Revisiting the effect of quality of graphics on distance judgments in virtual environments: A comparison of verbal reports and blind walking

In immersive virtual environments, judgments of perceived egocentric distance are significantly underestimated, as compared with accurate performance in the real world. Two experiments assessed the influence of graphics quality on two distinct estimates of distance, a visually directed walking task and verbal reports. Experiment 1 demonstrated a similar underestimation of distances walked to previously viewed targets in both low- and high-quality virtual classrooms. In Experiment 2, participants’ verbal judgments underestimated target distances in both graphics quality environments but were more accurate in the high-quality environment, consistent with the subjective impression that high-quality environments seem larger. Contrary to previous results, we suggest that quality of graphics does influence judgments of distance, but only for verbal reports. This behavioral dissociation has implications beyond the context of virtual environments and may reflect a differential use of cues and context for verbal reports and visually directed walking.     

Walk for well-being: The main effects of walking on approach motivation

The purpose of this study was to investigate the role of exercise in the development of self-efficacy and approach motivation. An 8-week blind experimental design was used (N?=?185), with two control and two treatment groups. Already physically active participants were assigned to one control group, while participants that reported a sedentary lifestyle at pretest were randomly assigned to either a sedentary control group or one of two treatment groups that began a brisk walking intervention. Treatment group participants walked either outdoors or indoors for 30 min per day, 4 days per week, for 8 weeks. The indoor/outdoor treatment group assignment was implemented to determine if exercising outdoors enhanced the outcomes. Significant main effects of walking were found for exercise self-efficacy, general self-efficacy and global approach motivation tendencies. Walking outdoors resulted in the greatest gains in general self-efficacy and global approach motivation. Given the alarmingly sedentary nature of American culture, these findings further evidence how simple changes in physical activity may have profound effects on well-being.

     

The influence of restricted viewing conditions on egocentric distance perception: implications for real and virtual indoor environments

We carried out three experiments to examine the influence of field of view and binocular viewing restrictions on absolute distance perception in real-world indoor environments. Few of the classical visual cues provide direct information for accurate absolute distance judgments to points in the environment beyond about 2 m from the viewer. Nevertheless, in previous work it has been found that visually directed walking tasks reveal accurate distance estimations in full-cue real-world environments to distances up to 20 m. In contrast, the same tasks in virtual environments produced with head-mounted displays (HMDs) show large compression of distance. Field of view and binocular viewing are common limitations in research with HMDs, and have been rarely studied under full pictorial-cue conditions in the context of distance perception in the real-world. Experiment 1 showed that the view of one's body and feet on the floor was not necessary for accurate distance perception. In experiment 2 we manipulated the horizontal and the vertical field of view along with head rotation and found that a restricted field of view did not affect the accuracy of distance estimations when head movement was allowed. Experiment 3 showed that performance with monocular viewing was equal to that with binocular viewing. These results have implications for the information needed to scale egocentric distance in the real-world and reduce the support for the hypothesis that a limited field of view or imperfections in binocular image presentation are the cause of the underestimation seen with HMDs.     

Meditating selflessly at the dawn of a new millennium

Increasingly open to question are the efficacies and timing of some traditional, conventional and current meditative techniques. Recent brain research emphasizes that it is important to distinguish between the Self-centred (egocentric) and other-centred (allocentric) streams of processing. It also proves useful to view as complementary the assets of the concentrative and receptive styles of meditation, especially when one's practices cultivate an appropriate balance between their top-down and bottom-up systems of attentive processing. From this neural perspective, Part I ventures a small sample of empirical suggestions. Some of these could help practitioners engage in more open, effortless, choiceless, varieties of receptive meditation–indoors and outdoors. Part II discusses recent research that illuminates issues arising at the interface between Self and other. The evidence suggests how a balanced attentiveness might enable long-term meditators to enhance mindfulness of the present moment, while simultaneously becoming much less fearful and, ultimately, freer to openly express their most objective, innate instincts of selfless compassion.

The art of Progress is to preserve order amid change and to preserve change amid order. (Alfred North Whitehead 1861–1947)     

The underestimation of egocentric distance: evidence from frontal matching tasks

There is controversy over the existence, nature, and cause of error in egocentric distance judgments. One proposal is that the systematic biases often found in explicit judgments of egocentric distance along the ground may be related to recently observed biases in the perceived declination of gaze (Durgin & Li, Attention, Perception, & Psychophysics, in press), To measure perceived egocentric distance nonverbally, observers in a field were asked to position themselves so that their distance from one of two experimenters was equal to the frontal distance between the experimenters. Observers placed themselves too far away, consistent with egocentric distance underestimation. A similar experiment was conducted with vertical frontal extents. Both experiments were replicated in panoramic virtual reality. Perceived egocentric distance was quantitatively consistent with angular bias in perceived gaze declination (1.5 gain). Finally, an exocentric distance-matching task was contrasted with a variant of the egocentric matching task. The egocentric matching data approximate a constant compression of perceived egocentric distance with a power function exponent of nearly 1; exocentric matches had an exponent of about 0.67. The divergent pattern between egocentric and exocentric matches suggests that they depend on different visual cues.     

Seeing beyond the target: environmental context affects distance perception

It is commonly assumed that perceived distance in full-cue, ecologically valid environments is redundantly specified and approximately veridical. However, recent research has called this assumption into question by demonstrating that distance perception varies in different types of environments even under full-cue viewing conditions. We report five experiments that demonstrate an effect of environmental context on perceived distance. We measured perceived distance in two types of environments (indoors and outdoors) with two types of measures (perceptual matching and blindwalking). We found effects of environmental context for both egocentric and exocentric distances. Across conditions, within individual experiments, all viewer-to-target depth-related variables were kept constant. The differences in perceived distance must therefore be explained by variations in the space beyond the target.     

Using verbal and blind-walking distance estimates to investigate the two visual systems hypothesis

Verbal estimates of egocentric distance are usually too short at distances greater than several meters, yet blindfolded walking to previously viewed targets can be surprisingly accurate. We present evidence from three experiments for the existence of two visual pathways with differentencodings of perceived egocentric distance. We found that (1) blind-walking estimates of egocentric distance are consistently more accurate than verbal reports; (2) an indoor versus outdoor environment selectively influences verbal reports; and (3) wearing prism lenses, which displace the visual field vertically, selectively influences the blind-walking estimates. We interpret these results in terms of the two visual systems hypothesis.     

Moving beyond counselling and psychotherapy as it currently is – taking therapy outside

Research was undertaken by the author in order to describe, interpret and explain what happens when counsellors and psychotherapists who have been trained to work indoors with their therapy clients take their therapy practice into outdoor natural spaces. A central research question addressed ‘What happens when counsellors and psychotherapists, who have been trained to work indoors with their therapy clients, take their therapy practice in to outdoor natural spaces?’ Semi-structured interviews were undertaken with therapists who practised outdoors. Three dominant themes emerged critiquing aspects of current counselling and psychotherapy practice. These were related to the unfolding ecological crisis, the context of the work and moving beyond current conceptions of distress and the role of therapy in addressing this.     

Prospective memory in a language-trained chimpanzee (Pan troglodytes)

Prospective memory involves the encoding, retention, and implementation of an intended future action. Although humans show many forms of prospective memory, less is known about the future oriented processes of nonhuman animals, or their ability to use prospective memory. In this experiment, a chimpanzee named Panzee, who had learned to associate geometric forms called lexigrams with real-world referents, was given a prospective memory test. Panzee selected between two foods the one she wanted to receive more immediately. That food was scattered in an outdoor yard where she could forage for it. Also outdoors were lexigram tokens, one of which represented the food item that remained indoors throughout a 30 min period, and that could be obtained if Panzee brought in the token that matched that food item. After foraging for the selected food item, Panzee consistently remembered to retrieve and return the correct token when food was available indoors, whereas on control trials involving no indoor food she rarely returned a token. This indicated that Panzee encoded information relevant to the future action of token retrieval after extended delays for one type of food, even when a more immediately preferred food was available.     

The effect of feedback training on distance estimation in virtual environments

It is often noted that distances are significantly underestimated in computer‐simulated (virtual) environments. Two experiments examine observers' ability to use error corrective feedback to improve the accuracy of judgments of egocentric and exocentric distances. In Experiment 1, observers viewed objects in an immersive virtual environment and estimated their distance through a blindfolded walking task. Different groups received feedback on either egocentric, exocentric or none of these judgments. Receiving feedback improved observers' ability to estimate only those distances for which feedback was provided. These effects persisted for at least 1 week. In Experiment 2, observers estimated egocentric distance by means of both a direct and indirect walking task. Receiving feedback on the direct walking task predominantly improved direct estimates and not indirect estimates. These findings suggest that although feedback training offers a relatively straightforward and immediate way of overcoming problems of distance estimation, its effects are specific to both the type of judgment and the type of response. Copyright © 2005 John Wiley & Sons, Ltd.     

Influence of Levels of Abstractness on Reasoning Ability

Judgment by students of faculty effectiveness have relied, for the most part, on subjectively expressed responses to a series of “effectiveness traits” (cues). Simple averaging schemes have summarized the aggregate judgments, often resulting in (a) treating all cues as if they were of equal importance, and (b) inattention to the effects or measurement of individual differences of judges.

Multiple regression was used in this study to derive (empirically) individual cue utilization patterns (i.e., weights) for 10 effectiveness traits. Ss were compared to their subjectively expressed judgment scheme. Results indicate that Ss were moderately successful in expressing their actual cue utilization patterns; however, different judgment schemes were clearly observed.     

Developmental Changes in Young Children's Spatial Memory and Language in Relation to Landmarks

Two experiments investigated how young children and adults understand whether objects are by a landmark and remember their locations. Three- and 4-year-old children and adults were asked to judge whether several blocks were by a landmark. The blocks were arranged so that their absolute and relative distances from the landmark varied. Later, the blocks were removed, and participants were asked to place them in their original locations. All ages relied on relative distance between objects and a landmark when making by judgments; however, older children and adults showed systematic judgments. Relative distance also affected block placement, and systematicity increased across development. Children's understanding of the relative nature of by and their ability to remember locations precisely increased during the preschool years, indicating developmental changes in the adaptive combination of location cues for spatial language and memory.     

Cycling outdoors facilitates external thoughts and endurance

ObjectivesThe aims of this study were twofold: (a) to compare the effects of indoor and outdoor environments on cycling endurance and thought dynamics, (b) to investigate a possible link between cycling endurance and the adherence to task-unrelated thoughts (TUT) in both environments. Design: An experimental, within-subject design with two-trial random assignment was used.MethodsParticipants (n = 13) cycled at constant power until volitional exhaustion while imposing TUT. They reported thought changes using self-selected key words that were subsequently classified based on task-relatedness (TUT, and task-related thoughts (TRT)) and direction (internal, external). Mean values of relative time spent in TUT and TRT categories were computed and compared for 5 equal time intervals. The association between cycling endurance and time spent at each thought-related category was analyzed.ResultsAnalyses revealed a decrease of TUT and an increase of TRT as a function of time (spent cycling) in both environments. Three qualitative thought phases emerged: an initially stable TUT phase was followed by a metastable phase characterized by shifts between TUT and TRT, and a final stable TRT phase appeared nearing exhaustion. Participants cycled longer outdoors than indoors M_outdoors = 12.54 min, SEM = 2.17 s, M_indoors = 11.35 min, SEM = 1.52 s (Z = −2.27, p < 0.05, d(95% CI) = 0.56 (−0.80, 3.07)), with a dominance of external thought categories. Cycling endurance seemed to be facilitated by TUT-E outdoors and TRT-I in both types of environments.ConclusionOutdoor environment resulted in improved cycling endurance and greater use of external thoughts (i.e., dissociative attentional strategy) relative to indoor environment. The effectiveness of thought categories seemed contingent upon their stability, which in turn depended on effort accumulation.     

Unprompted recall and reporting of hidden objects by a chimpanzee (Pan troglodytes) after extended delays

The ability to recall features of environments not present to the senses is important in human thinking, planning, and communication, but to date there are almost no data on recall capabilities in nonverbal animals. In this study, the author used symbol knowledge as a tool to study chimpanzee memory. An 11-year-old female chimpanzee (Pan troglodytes) that had already learned a large number of arbitrarily designated geometric forms (lexigrams) watched as an experimenter hid an object in the woods outside her outdoor enclosure. The type and location of the object varied across trials. After an imposed delay of up to 16 h, the chimpanzee could interact indoors with a person who did not know that an object had been hidden, let alone the type or location of the object. A keyboard in the indoor cage displayed 256 lexigrams. From Trial 1, the chimpanzee seemed to do whatever it took to catch the person's attention and then touched the lexigram corresponding to the type of object hidden, pointed outdoors, went outdoors (if followed), and continued to point manually toward the object and vocalize until the person found the object. The subject indicated nonfood objects as well as more than 20 food types.     

More than just perception–action recalibration: Walking through a virtual environment causes rescaling of perceived space

Egocentric distances in virtual environments are commonly underperceived by up to 50 % of the intended distance. However, a brief period of interaction in which participants walk through the virtual environment while receiving visual feedback can dramatically improve distance judgments. Two experiments were designed to explore whether the increase in postinteraction distance judgments is due to perception–action recalibration or the rescaling of perceived space. Perception–action recalibration as a result of walking interaction should only affect action-specific distance judgments, whereas rescaling of perceived space should affect all distance judgments based on the rescaled percept. Participants made blind-walking distance judgments and verbal size judgments in response to objects in a virtual environment before and after interacting with the environment through either walking (Experiment 1) or reaching (Experiment 2). Size judgments were used to infer perceived distance under the assumption of size–distance invariance, and these served as an implicit measure of perceived distance. Preinteraction walking and size-based distance judgments indicated an underperception of egocentric distance, whereas postinteraction walking and size-based distance judgments both increased as a result of the walking interaction, indicating that walking through the virtual environment with continuous visual feedback caused rescaling of the perceived space. However, interaction with the virtual environment through reaching had no effect on either type of distance judgment, indicating that physical translation through the virtual environment may be necessary for a rescaling of perceived space. Furthermore, the size-based distance and walking distance judgments were highly correlated, even across changes in perceived distance, providing support for the size–distance invariance hypothesis.     

Addiction as an indicator of vulnerability: The case of indoor tanning

Research concerning the marketing of potentially harmful products to vulnerable consumer segments reveals difficulties in identifying vulnerable consumers. Businesses must be able to identify such segments if they are to avoid regulation and consumer activism. Whether a measure of nonsubstance addiction is an appropriate indicator of vulnerability is examined here in the context of indoor tanning. Three studies of young adult tanners indicate that (a) a modified alcohol addiction scale, the CAGE index, can be used to measure other addictions; (b) addicted indoor tanners have high motivation to meet social appearance norms and to experience the feeling of tanning, which may make them susceptible to marketing cues for indoor tanning; and (3) addicted and nonaddicted indoor tanners are similar in their knowledge of the dangers of indoor tanning, thus supporting the assertion that addicted tanners' decisions to tan indoors are likely more influenced by addiction than by informed decision making.     

Skiing and its Discontents: Assessing the Turist Experience from a Psychoanalytical,a Neuroscientific and a Sport Philosophical Perspective

Abstract

This article addresses the question whether skiing as a nature sport enables practitioners to develop a rapport with nature, or rather estranges and insulates them from their mountainous ambiance. To address this question, I analyse a recent skiing movie (Turist, 2014) from a psychoanalytical perspective (skiing as a quest for self-knowledge and as therapy) and from a neuro-scientific perspective (ski resorts as laboratory settings for testing physical and psychic responses to a variety of cues). I conclude that Jean-Paul Sartre’s classical but egocentric account of his skiing experiences disavows the technicity involved in contemporary skiing as a sportive practice for the affluent masses, which actually represents an urbanisation of the sublime, symptomatic for the current era (the anthropocene).