Surface perception in pictures.

Subjects adjusted a local gauge figure such as to perceptually "fit" the apparent surfaces of objects depicted in photographs. We obtained a few hundred data points per session, covering the picture according to a uniform lattice. Settings were repeated 3 times for each of 3 subjects. Almost all of the variability resided in the slant; the relative spread in the slant was about 25% (Weber fraction). The tilt was reproduced with a typical spread of about 10 degrees. The rank correlation of the slant settings of different observers was high, thus the slant settings of different subjects were monotonically related. The variability could be predicted from the scatter in repeated settings by the individual observers. Although repeated settings by a single observer agreed within 5%, observers did not agree on the value of the slant, even on the average. Scaling factors of a doubling in the depth dimension were encountered between different subjects. The data conformed quite well to some hypothetical fiducial global surface, the orientation of which was "probed" by the subject's local settings. The variability was completely accounted for by single-observer scatter. These conclusions are based upon an analysis of the internal structure of the local settings. We did not address the problem of veridicality, that is, conformity to some "real object."     

On the nature and accuracy of attributions that change over time

“Actor” subjects engaged in a brief getting-acquainted conversation while “observer” subjects watched. Ratings of and causal attributions for behavior during the conversation were obtained immediately upon its conclusion and three weeks later from the same subjects and from an independent group of subjects not asked for immediate attributions. Comparison between immediate and the independent, “postponed” assessments showed that attributions by actors and observers tended to emphasize situational factors more over time, and personal factors less. Attributions by the “repeated assessment” subjects did not show a significant change over time, but their delayed attributions were significantly less likely to emphasize situational factors than were the delayed attributions of the “postponed assessment” group. The relative accuracy of these attributions could not, of course, be directly assessed. However, valid attributions presumably must be based upon valid perceptions or memories of the behaviors they seek to explain, and reliable criterion ratings of behaviors in the present study could be obtained from the experimenters. Actors' and observers' delayed behavior ratings agreed less with these criteria than did their immediate ratings, an indirect indication that attributions do not increase, and may decrease, in accuracy over time.     

Correspondence in pictorial space

ATR Human Information Processing Research Laboratories, Kyoto, Japan We have investigated psychophysically determined image correspondences between pairs of photographs of a single three-dimensional (3-D) object in various poses. These correspondences were obtained by presenting the pictures simultaneously, side by side, and letting the subject match a marker in one picture with a marker (under manual control) in the other picture. Between poses, the object was rotated about a fixed vertical axis; thus, the shifts of the veridical correspondences (with respect to the surface of the object) were very nearly horizontal. In fact, the subjects produced appreciable scatter in both horizontal and vertical directions. The scatter in repeated sessions and between data depends on the local (landmarks) and global (interpolation) structure of the pictures. Since the object was fairly smooth (white semigloss finish) and nontextured, the only way to establish the correspondence is by way of the “pictorial relief.” The relief is some largely unknown function of the image structure and the observer. Apparently, more immediate entities (e.g., the shading or the contour) cannot be used as such, since they vary with the pose. We compare these data with results obtained with a surface attitude probe on a single picture. We studied various measures of consistency both within a single method and between methods. We found that subjects were confident in establishing correspondences, but results scattered appreciably in a way that depended on both global and local image structure. Correspondence results for various pose angles were mutually very consistent, but only to a minor extent with results of attitude measurements. The main finding was that subjects could establish correspondence on the basis of their 3-D interpretation (pictorial relief), even if the 2-D graytone distributions are quite different.     

The within-subjects design in the study of facial expressions

The common within-subjects design of studies on the recognition of emotion from facial expressions allows the judgement of one face to be influenced by previous faces, thus introducing the potential for artefacts. The present study (N=344) showed that the canonical “disgust face” was judged as disgusted, provided that the preceding set of faces included “anger expressions”, but was judged as angry when the preceding set of faces excluded anger but instead included persons who looked sad or about to be sick. Chinese observers showed lower recognition of the “disgust face” than did American observers. Chinese observers also showed lower recognition of the “fear face” when responding in Chinese than in English.     

On the perception of symmetrical and repeated patterns

Four experiments investigated rapid perceptual judgments about tachistoscopically presented patterns that were either symmetrical about or repeated across a vertical axis. The same patterns were presented under two different instructional conditions; some Ss were to judge the two halves of each pattern “same” or “mirror,” others were to judge each pattern as a whole “symmetrical” or “asymmetrical.” With dot patterns, RTs were faster for symmetrical than for repeated patterns when the two halves were close together, but not when they were separated, regardless of instructions. With simpler patterns made up of arrowheads and C-shapes, however, “same” RTs were faster than “mirror,” but “asymmetrical” RTs were marginally slower than “symmetrical,” regardless of spatial separation. The advantage of “same” over “mirror” did not seem to be simply a labeling effect. The results suggest that left-right symmetry is perceptually more salient than left-right repetition when the patterns are perceived holistically. By contrast, distinct patterns can be matched more rapidly when they are the same than when they are left-right mirror images.     

Two memories for geographical slant: Separation and interdependence of action and awareness

The present study extended previous findings of geographical slant perception, in which verbal judgments of the incline of hills were greatly overestimated but motoric (haptic) adjustments were much more accurate. In judging slant from memory following a brief or extended time delay, subjects’ verbal judgments were greater than those given when viewing hills. Motoric estimates differed depending on the length of the delay and place of response. With a short delay, motoric adjustments made in the proximity of the hill did not differ from those evoked during perception. When given a longer delay or when taken away from the hill, subjects’ motoric responses increased along with the increase in verbal reports. These results suggest two different memorial influences on action. With a short delay at the hill, memory for visual guidance is separate from the explicit memory informing the conscious response. With short or long delays away from the hill, short-term visual guidance memory no longer persists, and both motor and verbal responses are driven by an explicit representation. These results support recent research involving visual guidance from memory, where actions become influenced by conscious awareness, and provide evidence for communication between the “what” and “how” visual processing systems.     

Aging and the perception of slant from optical texture, motion parallax, and binocular disparity

The ability of younger and older observers to perceive surface slant was investigated in four experiments. The surfaces possessed slants of 20°, 35°, 50°, and 65°, relative to the frontoparallel plane. The observers judged the slants using either a palm board (Experiments 1, 3, and 4) or magnitude estimation (Experiment 2). In Experiments 1–3, physically slanted surfaces were used (the surfaces possessed marble, granite, pebble, and circle textures), whereas computer-generated 3-D surfaces (defined by motion parallax and binocular disparity) were utilized in Experiment 4. The results showed that the younger and older observers' performance was essentially identical with regard to accuracy. The younger and older age groups, however, differed in terms of precision in Experiments 1 and 2: The judgments of the older observers were more variable across repeated trials. When taken as a whole, the results demonstrate that older observers (at least through the age of 83 years) can effectively extract information about slant in depth from optical patterns containing texture, motion parallax, or binocular disparity.     

Using Cognitive Dissonance to Encourage Water Conservation1

In a field experiment on water conservation, we aroused dissonance in patrons of the campus recreation facility by making them feel hypocritical about their showering habits. Using a 2 × 2 factorial design, we manipulated subjects “‘mindfulness” that they had sometimes wasted water while showering, and then varied whether they made a “public commitment” urging other people to take shorter showers. The “hypocrisy” condition-in which subjects made the public commitment after being reminded of their past behavior-was expected to be dissonance-arousing, thereby motivating subjects to increase their efforts to conserve water. The results were consistent with this reasoning. Compared to controls, subjects in the hypocrisy condition took significantly shorter showers. Subjects who were merely reminded that they had wasted water, or who only made the public commitment, did not take shorter showers than control subjects. The findings have implications for using cognitive dissonance as means of changing behavior in applied settings, especially those in which people already support the desired goal, but their behavior is not consistent with those beliefs.     

The visual contour in depth

We asked subjects to match points on the surface of a smooth three-dimensional (3-D) shape with points on the surface of another object that was geometrically identical to the first object but was placed in a different pose, was differently textured, and was differently shaded. In all cases, the fiducial point was on the rim of one of the objects (i.e., the boundary of the visible region of the surface), whereas the matching point was well within the silhouette of the other object. This allowed us to draw (preliminary) conclusions concerning the way monocular human observers are able to handle the neighborhood of the rim, where the local slant assumes arbitrarily high values. All experiments were done in real space with real objects (no computer-simulated scenes), the points being indicated with laser beam illumination. The subject was given control over the direction of the laser beams and was thus able to perform the task by adjustment from the vantage position. We studied both consistency (whether the subject’s judgments were invariant against changes of relative pose) and veridicality (whether the depth of the visual contour as calculated from the settings agreed with the true distance as measured by mechanical means). Subjects caught much of the 3-D structure of the contour but did deviate appreciably and apparently idiosyncratically from the true geometry.     

学前儿童对“知道”和“会”的认知

72名3至5岁儿童接受了陈述性知识和程序性知识的学习任务,探查他们在获得新知识前后对自己是否“知道”和 “会”的认知和知识获取方式的认知 。结果显示,有部分学前儿童在不知道或不会的情况下报告自己“知道”或“会”,对自己的判断倾向于作出肯定回答;在学习新知识之后,学前儿童对自己是否“知道”的认识要比是否“会”的认知准确;儿童对陈述性知识的获取方式的认识好于程序性知识,3岁儿童对知识获取方式的认识存在困难。     

The perception of 3-D structure from contradictory optical patterns

Two experiments investigated observers’ perceptions of 3-D structure when optical sources of information were contradictory. When motion and stereoscopic disparities specified different surfaces, the perceptual outcome depended strongly on the direction of curvature present within each modality. Previous research has shown that the perception of surface slant and curvature is anisotropic for both motion and stereo and that it depends on the direction in which it takes place. In the present experiments, the modality with the “effective” direction of curvature tended to dominate or suppress the perception of surfaces in the other modality with less effective curvatures. The results have implications for models which attempt to combine 3-D data from different optical sources.     

Variability of timing in expressive piano performance increases with interval duration

In simple motor tasks such as finger tapping at different constant rates, within-trial variability of response interonset intervals (IOIs) increases with IOI duration (which varies between trials). In expressive piano performance, the rate of key depressions is not constant, in part due to compositional structure and in part due to expressive timing, so that IOIs of many different durations occur within a single “trial.” Nevertheless, across repeated performances of the same music (Schumann’s “Träumerei” and Debussy’s “La fille aux cheveux de lin”) at the same intended tempo, the standard deviations of individual IOIs tend to increase linearly with their average duration. This is also true when the variation is due to expressive timing alone and when unintended differences in basic tempo between performances are taken into account. In the music studied here, at least, there was no evidence of compensatory timing. The results suggest that the pianists employed a continuously variable tempo governed by a flexible internal timekeeper whose variability follows a generalized Weber’s law (for IOIs longer than about 300 msec).     

Problems in the neighbourhood: Formulating noise complaints across dispute resolution services

When people are in dispute with their neighbours, there are multiple routes to resolution, and different services have a range of remits to support it. This article explores how noise complaints are reported to dispute resolution mediation and local council environmental services in the United Kingdom. A collection of 315 recorded telephone calls were transcribed and analysed using discursive psychology, underpinned by conversation analytic methods. Analysis focused on how the same kinds of noise complaint were formulated for the remit and provision of the service called. In mediation calls, callers directly attributed the source of the noise to the agent of its production (e.g., “it's about the neighbour”). However, reference to “the neighbour” was typically omitted (at least initially) in calls to environmental health services (e.g., “I need to speak to someone about disturbance”). This comparative analysis of different settings reveals the significance of service remit for the design of complaints and the relevance of attributing cause in making a case for aid. Comparing two settings provides a propitious opportunity to demonstrate that noise is not a physically objective phenomenon or neutral category but institutionally formulated social conduct.     

The dilution effect: Nondiagnostic information weakens the implications of diagnostic information

In a series of studies, subjects were asked to make predictions about target individuals. Some subjects were given information about the target which pretest subjects had judged to be “diagnostic”—that is, had judged to be usefully predictive of the outcome. Other subjects were given a mix of information judged to be diagnostic and information judged to be “nondiagnostic” by pretest subjects—that is, judged to be of little value for predicting the outcome. Subjects given mixed information made much less extreme predictions than did subjects given only diagnostic information. It was argued that this “dilution effect” occurs because people make predictions by making simple similarity judgments. That is, they compare the information they have about the target with their conception of outcome categories. The presence of individuating but nondiagnostic information about the target reduces the similarity between the target and those outcomes that are suggested by the diagnostic information. One of the major implications is that stereotypes and other “social knowledge structures” may be applied primarily to abstract, undifferentiated individuals and groups and may be largely set aside when judgments are made about concrete, individuated people.     

The stereoscopic anisotropy: individual differences and underlying mechanisms

Observers are more sensitive to variations in the depth of stereoscopic surfaces in a vertical than in a horizontal direction; however, there are large individual differences in this anisotropy. The authors measured discrimination thresholds for surfaces slanted about a vertical axis or inclined about a horizontal axis for 50 observers. Orientation and spatial frequency discrimination thresholds were also measured. For most observers, thresholds were lower for inclination than for slant and lower for orientation than for spatial frequency. There was a positive correlation between the 2 anisotropies, resulting from positive correlations between (a) orientation and inclination thresholds and (b) spatial frequency and slant thresholds. These results support the notion that surface inclination and slant perception is in part limited by the sensitivity of orientation and spatial frequency mechanisms.     

Visual orientation by motion-produced blur patterns: Detection of divergence

Blur patterns are physiological “streaks” of photochemical and neural activity that occur whenever an observer and his visual environment are in relative motion. When retinal velocities are high, the impression of visual “flow” gives way to one of a field of “blur lines” whose patterns are rich with information about the motions and the optical textures that produced them. Simulated blur patterns were produced and thresholds measured for the detection of divergence at nine retinal loci. Sensitivity was somewhat greater in the central retina. Thresh-olds remained the same despite variations in pattern velocity, number of elements, and the presence or absence of an internal velocity gradient. Observers were able to orient above-threshold patterns, but consistently underestimated the amount of slant.     

Parents' disclosure of their own concerns to their adolescent children

This study examines middle-aged parents' disclosure about their own lives and current concerns, with their late-adolescent children. Three hundred seventy-two parents of college freshmen, averaging 47 years of age, participated by filling out an anonymous questionnaire that asked about 28 topics, varying in intimacy, of concern to adults. The subjects indicated whether they had discussed each topic with their child, and, if they had, the motivations that prompted them to do so. The data revealed that mothers disclosed more than did fathers, and they were more likely to cite “venting,”“asking advice,” and “seeking emotional support” as reasons for disclosure; fathers were more likely to cite “trying to change his/her behavior” as a rationale for disclosure. Child's gender did not affect disclosure rates, but sons and daughters were disclosed to for different reasons. Divorced parents disclosed more than did parents from continuously intact families, and they cited somewhat different reasons for disclosure.     

The determination of perceived tridimensional orientation by minimum criteria

The hypothesis investigated is that the perceived tridimensional orientation of an object is determined, in monocular vision, by tendencies to make the perceived object as simple as possible. Line drawings seen as “boxes” were viewed by Os who judged the slant fangle with frontal plane) of various edges. For every such edge, there is a determinate hypothetical slant consistent with perfect homogeneity of values on one or more of three variables (angle, length, and slope) Perceived slant was highly predictable from hypothetical slant, though always with some regression to the frontal plane. Results add support to aPrägnanz or minimum-principle theory of space perception.     

Measuring the visual angle of the mind's eye

People in these experiments claimed to be able to imagine moving only a given distance toward some imaged object before it seemed to “overflow,” not remaining all visible at once in their mental images. In addition, the larger the imaged object, the further away it seemed at the point of overflow. Although the angle subtended by the imaged objects at the point of overflow did not vary systematically with the size of the object, it did vary with different stimuli and instructions. These disparities in the size of the angle estimated seemed partly due to differences in criterion of “overflow”: Images seem to fade off gradually toward the periphery and not to occur in a spatial medium with sharply defined edges. When subjects were given a relatively strict definition of “overflow,” similar estimates of the “visual angle of the mind's eye” were obtained with three distinct methods: (1) Asking subjects to estimate the apparent distance at which an imaged horizontal ruler began to overflow; (2) Measuring how much time subjects required to scan across each degree of an imaged line, and then inferring the maximal angle from the time required to scan an image of a longest nonoverflowing line; and, (3) Simply asking subjects to hold up their hands to indicate the subjective size of an image of the longest possible nonoverflowing line. Finally, the maximal subjective size of images seemed related to the scope of “focal” vision, and images tended to be constructed spontaneously at about the maximal size.