Size-distance Invariance Research Articles

Instructions and Knowledge of the Situation in Brightness Perception

The influence of information and instructions on brightness perception was investigated under conditions where either ratio or retinal matches were possible. Unlike most earlier studies, this one found no effect of experience: both trained and control groups showed identical ratio responses. The importance of obtaining perceptual rather than cognitive reports is emphasized in accounting for the contradictions in the literature. Experience and training have been shown to influence the perception of shape, size, and brightness.1 It is of particular note that constancy for each has also been shown to be affected by instructions requiring observers to make retinal rather than phenomenal reports of their observations.2 The susceptibility of such basic phenomena to learning has been argued strenuously by the transactionalists and to a lesser degree, by gestaltists as well.3 But it is Received for publication July 22, 1969. 1 On shape, see P. K. Leppmann and R. B. Mefferd, Jr., Validity of perceptual reports of experienced and inexperienced observers, Percept. mot. Skills, 26, 1968, 1167-1172; R. B. Mefferd, Jr., Betty A. Wieland, D. G. Greenstein, and P. K. Leppman, Effects of pretraining and instructions on validity of perceptual reports by inexperienced observers, Percept. mot. Skills, 27, 1968, 1003-1006. On size, see H. R. Schiffman, Size-estimation of familiar objects under informative and reduced conditions of viewing, this JOURNAL, 80, 1967, 229-235. On brightness, see R. G. Hopkinson, An experiment on the assessment of brightness under 'free-choice' and 'forced-choice' conditions by a group of observers, Ergonomics, 3, 1960, 44-50. 2 A. A. Landauer, The effect of instructions on the judgment of brightness, Quart. J. exp. Psychol., 16, 1964, 23-29; A. A. Landauer and R. S. Rodger, Effect of apparent instructions on brightness judgments, J. exp. Psychol., 68, 1964, 80-84; M. Parrish and K. Smith, Simultaneous brightness contrast as a function of perceptual set, Psychon. Sci., 7, 1967, 155-156; A. A. Landauer, Influence of instructions on judgments of unfamiliar shapes, J. exp. Psychol., 79, 1969, 129-132; W. H. Lichte and C. R. Borresen, Influence of instructions on degree of shape constancy, J. exp. Psychol., 74, 1967, 538-542; V. R. Carlson and E. P. Tassone, Size-constancy judgments at equal distances, Percept. mot. Skills, 27, 1968, 193-194. The terms used in the instructions of these studies to contrast the two attitudes have included: analytic, critical, objective, physical, projective, real, vs. apparent, immediate, naive, perceived, synthetic, whole. 3 On the transactionalists, see W. H. Ittelson, The constancies in perceptual theory, Psychol. Rev., 58, 1951, 285-294; W. H. Ittelson and F. P. Kilpatrick, Experiments in perception, Sci. Amer., 185, 1951, 50-55; F. P. Kilpatrick and W. H. Ittelson, The size-distance invariance hypothesis, Psychol. Rev., 60, 1953, This content downloaded from 157.55.39.114 on Mon, 25 Apr 2016 06:56:53 UTC All use subject to http://about.jstor.org/terms NOTES AND DISCUSSION 131 surprising to find brightness included among those phenomena shown to be affected by experience. MacLeod's early investigation did not find it so, nor would such an effect seem consistent with the great body of work which places brightness perception within a psychophysical framework.4 Furthermore, in contrast to shape and size, brightness is thought of as being more stimulus-bound and dependent upon retinal factors. Thus, the treatment of brightness and brightness constancy as a function of ratios of intensities explicitly rules out the traditional explanation of 'taking illumination into account,' i.e. denies the role of knowledge. Finally, everyday observations of objects in different illuminations (and the observations in the Gelb and Katz demonstrations) do not appear to be events easily amenable to phenomenal change as a result of knowledge of the situation or of conscious attempts to reverse one's percept.7 The purpose of this study was to investigate whether maximizing observers' critical understanding and approach to a brightnessperception task would indeed lead to a change in the outcome. To this end, two groups differing in their knowledge of the situation and in their instructions were asked to make brightness matches under ratio conditions of illumination. Thus, the structural factors thought responsible for brightness perception would be shown to persist if observers made ratio rather than retinal matches despite circumstances which favored the opposite result.

Size-distance judgments with random letter stereoarams

Using random letter stereograms, the size-distance relationship was investigated in the absence of a number of distance cues that are typically present when objects and drawings are used as stimuli. With depth differences signaled only by differences in binocular disparity, Ss reported that the apparently farther of two equal-sized stereoscopic images appeared larger as predicted by the size-distance invariance hypothesis. However, distance judgments of equally displaced figures were largely independent of relative size variations. Order of report of relative size and relative distance, figure placement with respect to the ground, and relative matrix densities of figures and ground did not reliably affect judgments.

The sensing of retinal size

This study examines the interpretation that under reduced conditions of observation the perceived size of an object is the result of a direct response to retinal size. In opposition to this interpretation is the size-distance invariance hypothesis stating that a perceived size results from a retinal size only when an appropriate perceived distance is also present. Four experiments were conducted. The first two experiments indicate that in the absence of distance cues, perceived size is proportional to retinal size. The last two experiments suggest that this result is a consequence of the tendency, under reduced conditions, to perceive the objects at a common (specific) distance. The results support the size-distance invariance hypothesis and are in opposition to the direct perception of retinal size. The possible significance of the specific distance tendency is discussed for binocular as well as monocular conditions of observation.

The influence of haptic size information upon visual judgments of absolute distance

When O views a blank triangle of light under completely reduced conditions, he is able to use information about the size of this visual stimulus conveyed via the haptic modality when he is attempting to judge the absolute distance of the visual stimulus. However, distance is consistently underesti-mated in this situation. When haptically-indicated size is held constant, judged distance varies inversely with retinalsubtense, even though the different retinal subtenses are viewed by different Os. A variant of the size-distance invariance hypothesis also appears to hold in these circumstances.

Depth, size and distance in stereoscopic vision

Evidence is presented to show that in stereoscopic vision a constant ratio of perceived size to perceived distance corresponds to a constant visual angle (the size-distance invariance hypothesis). The functions relating the size/ distance ratio to visual angle and the depth/distance ratio to disparity are determined for three as using the methods of magnitude estimation and magnitude production. The results for each a may be represented by power functions, the depth/ distance function having the higher exponent. These scales are used to predict the outcome of an experiment in which depth is matched to size. The agreement of predictions with results is good for the combined data of the group, but significant deviations occur from curves predicted for individual as. An experiment in which an oblique line is matched to a frontal extent yields data consistent with Luneburg’s hypothesis that the intrinsic geometry of visual space is non-Euclidean. The indicated curvature is negative for two as and varying from positive to negative for the third.

The Size-Distance Invariance Hypothesis: A Reply to Cook

The Size-Distance Invariance Hypothesis: A Reply to Cook

Effect of Speed of Movement on Tactual-Kinesthetic Perception of Extent

The analysis of perception of extent in the visual modality has been largely restricted to a static, geometric characterization in terms of the dependency of retinal size on the physical size and distance of an object from the retinal plane (size-distance invariance hypothesis).' In contrast, analysis of perception of extent in the tactual-kinesthetic modality provides the basis for a dynamic analysis of the relation between quality of organismic activity (e.g., speed of movement) involved in perception, and object properties (e.g. size, extent) which are perceived through such activity. It is assumed that variation in quality of activity (e.g. fast vs. slow rate of traversing a given physical extent) makes for a difference in perceived extent.

Analysis of perspective reversal and associated apparent motions using a perspective-bound movement illusion.

The nature of perspective reversal was examined using among other techniques a previously undescribed movement illusion specific to the non-veridical perception of actual depth. The apparent movement of the illusion proved to be veridical parallax movement displaced spatially. Apparent changes in direction of rotation and apparent oscillation were shown to be consequences of perspective. Objects seen in reversed perspective illustrated spectacularly the size-distance invariance. Detailed analysis revealed that depth perception per se is veridical, and only the apparent relocations of parts are involved in perspective reversal. When a perspective reverses, O misperceives the location of the near and far parts of the object, but those parts “reverse” about the veridical center in situ and on a strictly 1:1 depth basis. Perspective changes occur only at a plane perpendicular to O in the depth dimension—never in the horizontal-vertical plane. Parts of a single figure may reverse independently of others, thereby forming a separate perceptual unit, the configuration of which is determined by O‘s position rather than by properties of the stimulus. More complex figures (e.g., a rectangular prism composed of three cubes), may be perceived as an entire Gestalt, or as various smaller independent units each reversing perspective independently as verified by the movement illusion. The analysis of the nature of perspective reversal suggests that depth perception is composed of at least two processes: first, the perception of absolute depth, and second, the spatial ordering of objects or points on objects. The first process seems not to be related to perspective reversal, but the second seems to be implicated as the critical one. The depth dimension necessarily is represented nonveridically as a flat projection on the retina, while those parts of the visual field that are perpendicular to O are represented veridically. When O “reconstructs” the depth dimension from this flat retinal image (whether the depth is real or only apparent in the stimulus), depending on how he interprets the order of the corresponding parts, he will perceive the object in true or false perspective.

Size-Distance Invariance and Perceptual Constancy

Koffka's concept of perceptual invariants appeared for a time to offer at least a useful simplification for the description of a number of perceptual phenomena.' His hypothesis of invariants in the relationships of perceived size and distance, shape and slant and the like, would still seem to be implicit in a number of discussions of the perceptual constancies.2 For the case of size and distance, the hypothesis commonly takes the form: A retinal projection or visual angle of given size determines a unique ratio of apparent size to apparent distance.3 As soon, however, as we attempt to express this proposition in terms of laboratory-operations, difficulties arise are due to the sheer variety of psychophysical procedures and instructional sets may be used in obtaining explicit judgments of size and distance. It cannot be expected different psychophysical methods for obtaining explicit judgments, under different instructional sets, will be in one-to-one correspondence with each other. Hence, it can hardly be assumed any one of these procedures will be in perfect quantitative correspondence with 'apparent' size or distance. It is really not surprising, then, a good deal of evidence has been accumulated by now which shows the invariance-hypothesis is by no means universally valid. The field has been well reviewed recently by Epstein, Park, and Casey.4 In many ways, the most convincing type of evidence bearing on the invariance-hypothesis comes from experimental situations in which stimulus-correlates of one perceived attribute are manipulated experimentally, and explicit judgments of the other attribute are studied as a result of these variations. This type of procedure is described by Epstein et al. as an attempt to show that a variable having a consistent influence on sizejudgments has no consistent influence on distance-judgments or vice versa.5 Their review cites four such studies yielding results contrary to the

Attitudes of judgment and the size-distance invariance hypothesis.

Attitudes of judgment and the size-distance invariance hypothesis.

A test of the size-distance invariance hypothesis.

Abstract : The size-distance invariance hypothesis was tested using three magnitudes of effective interpupillary distance (base). Devices providing an increased, normal, or decreased base were used to view targets at 5, 10, 15, or 20 ft. Both perceived relative and perceived absolute sizedistance invariance hypothesis which states that, for an object of constant angular size, the ratio of perceived absolute siznce is a constant. It was found that while perceived absolute size and perceived absolute distance were related, the ratio of the two varied significantly as a function of both physical distance and base. (Author)