A dissociation between object manipulation spatial ability and spatial orientation ability

We developed psychometric tests of spatial orientation ability, in which people are shown a two-dimensional array of objects, imagine taking a perspective within the array, and indicate the direction to a target object from this perspective. Patterns of errors on these tests were consistent with experimental studies of perspective taking. Characteristic errors and verbal protocols supported the validity of the perspective-taking tests, suggesting that people encoded the objects in the display with respect to a body-centered coordinate system when the imagined perspective was more than 90 degrees different from the orientation of the display. By comparing alternative models in a confirmatory factor analysis, we found that the ability to mentally rotate and manipulate an imagined object (as measured by tests of spatial visualization and spatial relations) and the ability to reorient the imagined self (as measured by the perspective-taking tests) are separable spatial abilities.     

The modified star graph and the petal diagram: two new visual aids for discrete alternative multicriteria decision making

Many studies have looked into the provisions of visual aids to multicriteria decision making. However, most of them have separated the display of alternative profiles and criteria weight information into two displays. This makes the analysis of the relationship between the criteria and alternatives and the effect of changing the criteria weights on the decision difficult. In this study, displays that can incorporate the display of both alternative profiles and criteria weight information for discrete alternative multicriteria decision-making problems are examined. The simple additive model is the multicriteria analysis method used. The result is two new visual aids for representing data of multicriteria decision-making problems, the modified star graph and the petal diagram. This paper discusses the two displays and compares their strengths and weaknesses. The results of a preliminary test conducted to evaluate the effectiveness of the displays are also included. © 1998 John Wiley & Sons, Ltd.     

Animal experimentation: The legacy of Claude Bernard

Claude Bernard, the father of scientific physiology, believed that if medicine was to become truly scientific, it would have to be based on rigorous and controlled animal experiments. Bernard instituted a paradigm which has shaped physiological practice for most of the twentieth century. In this paper we examine how Bernard's commitment to hypothetico‐de‐ductivism and determinism led to (a) his rejection of the theory of evolution; (b) his minimalization of the role of clinical medicine and epidemiological studies; and (c) his conclusion that experiments on non‐human animals were, “entirely conclusive for the toxicology and hygiene of man”. We examine some negative consequences of Bernardianism for twentieth century medicine, and argue that physiology's continued adherence to Bernardianism has caused it to diverge from the other biological sciences which have become increasingly infused with evolutionary theory.     

It takes two: the interpersonal nature of empathic accuracy

Although current theories suggest that affective empathy (perceivers' experience of social targets' emotions) should contribute to empathic accuracy (perceivers' ability to accurately assess targets' emotions), extant research has failed to consistently demonstrate a correspondence between them. We reasoned that prior null findings may be attributable to a failure to account for the fundamentally interpersonal nature of empathy, and tested the prediction that empathic accuracy may depend on both targets' tendency to express emotion and perceivers' tendency to empathically share that emotion. Using a continuous affect-rating paradigm, we found that perceivers' trait affective empathy was unrelated to empathic accuracy unless targets' trait expressivity was taken into account: Perceivers' trait affective empathy predicted accuracy only for expressive targets. These data suggest that perceivers' self-reported affective empathy can indeed predict their empathic accuracy, but only when targets' expressivity allows their thoughts and feelings to be read.     

A comparison of methods for estimating directions in egocentric space

A central issue for researchers of human spatial knowledge, whether focused on perceptually guided action or cognitive-map acquisition, is knowledge of egocentric directions, directions from the body to objects and places. Several methods exist for measuring this knowledge. We compared two particularly important methods, manual pointing with a dial and whole-body rotation (body heading), under various conditions of sensory or memory access to targets. In two experiments, blindfolded body rotation resulted in the greatest variability of performance (variable error), while the manual dial resulted in greater consistent bias (constant error). The variability of performance with body rotation was no greater than that of the dial when subjects' memory loads for directions to targets was reduced by allowing them to peek at targets in between trials, point to concurrent auditory targets, or point with their eyes open. In both experiments, errors with the manual dial were greater for directions to targets that were further from the closest orthogonal axis (ahead, behind, right, left), while errors with body rotation with restricted perceptual access were greater for directions to targets that were further from an axis straight ahead of subjects. This suggests that the two methods will produce evidence of different organizational frameworks for egocentric spatial knowledge. Implications for the structures and processes that underlie egocentric spatial knowledge, and are involved in estimating directions, are discussed, as is the value of decomposing absolute errors into variable and constant errors.     

Choosing and using geospatial displays: effects of design on performance and metacognition

Interactive display systems give users flexibility to tailor their visual displays to different tasks and situations. However, in order for such flexibility to be beneficial, users need to understand how to tailor displays to different tasks (to possess "metarepresentational competence"). Recent research suggests that people may desire more complex and realistic displays than are most effective (Smallman & St. John, 2005). In Experiment 1, undergraduate students were tested on a comprehension task with geospatial displays (weather maps) that varied in the number of extraneous variables displayed. Their metacognitive judgments about the relative effectiveness of the displays were also solicited. Extraneous variables slowed response time and increased errors, but participants favored complex maps that looked more realistic about one third of the time. In Experiment 2, the eye fixations of undergraduate students were monitored as they performed the comprehension task. Complex maps that looked more realistic led to more eye fixations on both task-relevant and task-irrelevant regions of the displays. Experiment 3 compared performance of experienced meteorologists and undergraduate students on the comprehension and metacognitive tasks. Meteorologists were as likely as undergraduate students to prefer geographically complex (realistic) displays and more likely than undergraduates to opt for displays that added extraneous weather variables. However, meteorologists were also slower and less accurate with complex than with simple displays. This work highlights the importance of empirically testing principles of visual display design and suggests some limits to metarepresentational competence.     

Vision and intelligence at age 83 in the Lothian Birth Cohort 1921

The extent to which visual function, measured as near and distant visual acuity and contrast sensitivity, is correlated with concurrently measured cognitive function and prior intellectual ability was investigated in a narrow age range group known as the Lothian Birth Cohort of 1921 (LBC1921). Participants were aged ~ 83 years at the time of testing (N = 321). A well-fitting structural equation model highlighted a significant contribution of a latent visual trait to a general fluid intelligence factor in old age, independent of the contribution from childhood intelligence. Additionally, childhood intelligence made a significant contribution to the general visual factor in old age. However, the model fitted equally well when the fluid intelligence factor is assumed to be a cause of the visual function latent trait, in which case childhood intelligence does not significantly influence vision in old age. We discuss these results with respect to four possible mechanisms by which vision and cognition can come to be correlated over the lifecourse.     

Sleep-related attentional bias in good, moderate, and poor (primary insomnia) sleepers

Evidence was sought of an attentional bias toward a highly representative object of the bedroom environment in good, moderate, and poor (primary insomnia) sleepers. Using a flicker paradigm for inducing change blindness, the authors briefly presented a single scene comprising a group of bedroom environment and neutral objects to participants and then briefly replaced this scene with an identical scene containing a change made to either a bedroom environment or a neutral object. In a 3 x 2 entirely between-participants design, change-detection latencies revealed a sleep-related attentional bias in poor sleepers but not in good sleepers. A possible bias in moderate sleepers was also revealed. It is suggested that attentional bias has a role in the perpetuation and possibly precipitation of primary insomnia.