Representation and perception of scenic layout

This paper presents a cognitive approach to on-line spatial perception within scenes. A theoretical framework is developed, based on the idea that experience with a scene can activate a complex representation of layout that facilitates subsequent processing of spatial relations within the scene. The representations integrate significant, relevant scenic information and are substantial in amount or extent. The representations are active across short periods of time and across changes in the retinal position of the image. These claims were supported in a series of experiments in which pictures of scenes (primes) facilitated subsequent spatial relations processing within the scenes. The prime-induced representations integrated object identity and layout, were broad in scope, involved both foreground and background information, and were effective across changes in image position.     

Processing spatial layout by perception and sensorimotor interaction

Everyone has the feeling that perception is usually accurate - we apprehend the layout of the world without significant error, and therefore we can interact with it effectively. Several lines of experimentation, however, show that perceived layout is seldom accurate enough to account for the success of visually guided behaviour. A visual world that has more texture on one side, for example, induces a shift of the body's straight ahead to that side and a mislocalization of a small target to the opposite side. Motor interaction with the target remains accurate, however, as measured by a jab with the finger. Slopes of hills are overestimated, even while matching the slopes of the same hills with the forearm is more accurate. The discrepancy shrinks as the estimated range is reduced, until the two estimates are hardly discrepant for a segment of a slope within arm's reach. From an evolutionary standpoint, the function of perception is not to provide an accurate physical layout of the world, but to inform the planning of future behaviour. Illusions - inaccuracies in perception - are perceived as such only when they can be verified by objective means, such as measuring the slope of a hill, the range of a landmark, or the location of a target. Normally such illusions are not checked and are accepted as reality without contradiction.     

The ground dominance effect in the perception of 3-D layout

The relative effectiveness of the ground surface and other environmental surfaces (the ceiling and sidewalls) in determining perceived layout was investigated in five experiments and a real-world demonstration. In the first three experiments, two vertical or horizontal posts were positioned between two surfaces (ground and ceiling in all three experiments, left wall and right wall in Experiment 1), and optical contact was manipulated so that the two surfaces provided contradictory information about the relative distances of the posts. Observers judged which of the two posts appeared to be closer. In Experiment 4, to control the height on the posts at which the distance judgments were made, a blue dot was attached to both vertical posts at varying heights and observers judged which dot appeared closer. In Experiment 5, the posts were replaced by two gray ellipses to eliminate the effects of the regular shape and texture. Our findings were that (1) among all four surfaces tested, observers showed a preference to respond according to the optical contact information provided by the ground surface--a ground dominance effect, (2) this effect did not depend on the height of the posts in the image, (3) as the scene was tilted away from a ground/ceiling orientation, the ground dominance effect decreased, and (4) this effect was not due to the location of the judgment.     

The independence of size perception and distance perception

Research on distance perception has focused on environmental sources of information, which have been well documented; in contrast, size perception research has focused on familiarity or has relied on distance information. An analysis of these two parallel bodies of work reveals their lack of equivalence. Furthermore, definitions of familiarity need environmental grounding, specifically concerning the amount of size variation among different tokens of an object. To demonstrate the independence of size and distance perception, subjects in two experiments were asked to estimate the sizes of common objects from memory and then to estimate both the sizes and the distances of a subset of such objects displayed in front of them. The experiments found that token variation was a critical variable in the accuracy of size estimations, whether from memory or with vision, and that distance had no impact at all on size perception. Furthermore, when distance information was good, size had no effect on distance estimation; in contrast, at far distances, the distances to token variable or unknown objects were estimated with less accuracy. The results suggest that size perception has been misconceptualized, so that the relevant research to understand its properties has not been undertaken. The size-distance invariance hypothesis was shown to be inadequate for both areas of research.     

Odors and the perception of hygiene

Although certain odors, such as lemon, are commonly associated with cleanliness and positive hygiene, empirical assessment of such associations for other odors and attributes is generally lacking. Moreover, differences between men and women in such associations have not been established. In this study of lemon, onion, pine, and smoke odors, ratings were obtained from 142 men and 336 women (M age= 30.1 yr., SD = 12.3) for odor intensity, gender association (masculine/feminine), and the success, sociability, intelligence, cleanliness, and attractiveness of a hypothetical person whose clothes smell like the odor in question. Ratings of the pleasantness or unpleasantness one would attribute to each odor in various rooms of the home were obtained, as well as a specification of whether such ratings are influenced by laundry habits, e.g., whether laundry is smelled before or after washing. Numerous associations were found. For example, a hypothetical person whose clothes smell of pine was rated as relatively more successful, intelligent, sociable, sanitary, and attractive than one whose clothes smelled of lemon, onion, or smoke. Sex differences, as well as differences between people who reported smelling their own laundry, were also found.     

Attitude and the perception of faces

To assess the effects of affective orientation on the judgment of facial attriutes, 165 subjects were asked to make judgments of the attributes of each of two faces. For each face, subjects were either given no information about the person in the photo, or were given biographical information connoting either a favorable or unfavorable personality. It was predicted that when subjects make judgments along dimensions that were evaluatively loaded (e.g., smilling vs frowning mouth), manipulated attitude would influence these judgments. For the seven dimensions rated by the subjects, four dimensions showed the predicted effect. The other three dimensions, which did not show the effect, were the only ones that showed a significant effect due to the face itself. It was concluded that for dimensions that are not highly structured by the characteristics of the face, attitude can significantly influence judgments of facial attributes.     

Aging and the perception of speed

Two experiments were conducted to explore the potential effects of aging upon the perception and discrimination of speed. In the first experiment, speed difference thresholds were obtained for younger and older observers for a variety of standard speeds ranging from slow to fast. The second experiment was designed to evaluate the observers' ability to discriminate differences in the speed of moving patterns in the presence of significant amounts of noise (the noise was manipulated by limiting the lifetimes of individual moving stimulus elements). The results of both experiments revealed a significant deterioration in the ability of the older observers to perceive or detect differences in speed. While the presence of noise was found to affect the observers' discrimination performance, it affected both younger and older observers' thresholds in a proportionally equivalent manner-the older observers were no more affected by noise than the younger observers.     

Routine and the perception of time

The authors investigated the influence of routine on people's estimation of time, testing the hypothesis that duration is remembered as being shorter when time is spent in a routine activity. In 4 experiments and 2 field studies, the authors compared time estimations in routine and nonroutine conditions. Routine was established by a sequence of markers (Study 1), variation of the task (Studies 2 and 3), or the number of repetitive blocks (Study 4). As hypothesized, the duration of the task was remembered as being shorter in routine conditions than in nonroutine ones. This trend was reversed in experienced (prospective) judgments when participants were informed beforehand of the duration-judgment task (Study 3). In Studies 5 and 6, the authors examined remembered duration judgments of vacationers and kibbutz members, which provided further support for the main hypothesis.     

Causality and the perception of time

Does our perception of when an event occurs depend on whether we caused it? A recent study suggests that when we perceive our actions to cause an event, it seems to occur earlier than if we did not cause it.     

Language and the perception of emotion

Three studies assessed the relationship between language and the perception of emotion. The authors predicted and found that the accessibility of emotion words influenced participants' speed or accuracy in perceiving facial behaviors depicting emotion. Specifically, emotion words were either primed or temporarily made less accessible using a semantic satiation procedure. In Studies 1 and 2, participants were slower to categorize facial behaviors depicting emotion (i.e., a face depicting anger) after an emotion word (e.g., "anger") was satiated. In Study 3, participants were less accurate to categorize facial behaviors depicting emotion after an emotion word was satiated. The implications of these findings for a linguistically relative view of emotion perception are discussed.     

The independence of size perception and distance perception.

Research on distance perception has focused on environmental sources of information, which have been well documented; in contrast, size perception research has focused on familiarity or has relied on distance information. An analysis of these two parallel bodies of work reveals their lack of equivalence. Furthermore, definitions of familiarity need environmental grounding, specifically concerning the amount of size variation among different tokens of an object. To demonstrate the independence of size and distance perception, subjects in two experiments were asked to estimate the sizes of common objects from memory and then to estimate both the sizes and the distances of a subset of such objects displayed in front of them. The experiments found that token variation was a critical variable in the accuracy of size estimations, whether from memory or with vision, and that distance had no impact at all on size perception. Furthermore, when distance information was good, size had no effect on distance estimation; in contrast, at far distances, the distances to token variable or unknown objects were estimated with less accuracy. The results suggest that size perception has been misconceptualized, so that the relevant research to understand its properties has not been undertaken. The size-distance invariance hypothesis was shown to be inadequate for both areas of research.     

Personality and the perception of TV violence

An experiment was carried out to investigate relationships between individuals' personality characteristics and their perceptions of violent TV portrayals. A panel of 40 viewers rated brief violent episodes from five categories of programming, contemporary British crime-detective series, American police series, westerns, science-fiction series and cartoons on eight scales. These responses were then related to viewers' scores on the N, E and P dimensions of the EPQ. Results showed that violent scores from contemporary settings were rated as more serious than scores from non-contemporary and fantastic settings. In addition, viewers exhibited individual differences in ratings of TV violence which were related to certain of their EPQ scores. In particular, high N scorers tended to perceive violence generally, but especially that from contemporary British drama, as more serious than did low N scorers. This study indicates the need to include personality measures in the analysis of audience reactions to TV violence.     

Bilingualism and the perception of professional concepts

A selected set of professional concepts was subjected to analysis through two separate multidimensional scaling techniques, the INDSCAL and TORSCA models, to evaluate the intergroup perceptual differences of four experimental groups, made up of unilingual French, unilingual English and bilingual students. The linguistic relativism thesis provided the research hypotheses on the relationship between language access and usage and concept perception. The multidimensional scaling techniques were applied to the matrix of subjects' similarity judgments on pairs of concepts, thus enabling the identification of three dimensions. The dimensions were labelled as conjunctive, relational and disjunctive, and were assumed to be related to the criteria employed by the subjects in their similarity rankings. An analysis of variance of the individual saliences on each dimension provided evidence of linguistic relativism for both the relational and disjunctive dimensions. These findings support the contention that unilingual speakers of separate languages differ from each other and from bilingual speakers in their perception of professional concepts.