The independence of size perception and distance perception

Abstract

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.

Observing and engaging in purposeful actions with objects influences estimates of their size

“…As Haber and Levin (2001) have pointed out, use of memory data for assessment of the size of familiar objects is logically compatible with the function of the ventral stream. We believe, however, that the system does not rigidly employ stored size data.…”

“…We were interested to see whether experience also would influence size estimates when the object was present. If hypotheses that posit that estimates of the size of familiar objects use size estimates stored in memory (Haber & Levin, 2001;Wesp et al, 2000) are correct, the errors we showed in Experiments 1 and 2 should also occur when the object is present. We replicated the procedures we used in the experiment in which the participants threw darts (Experiment 2), but the participants judged the size of the target while the target was visible.…”

“…At least two recent reports (Haber & Levin, 2001;Wesp, Peckyno, McCall, & Peters, 2000) have proposed that size estimates of familiar objects are not dependent on on-line information about retinal size and distance but, instead, are driven by higher order memory processes. Haber and Levin showed higher accuracy for size estimates of familiar objects that tend not to vary in size from a prototype than for estimates of the size of objects for which there is a wider range of sizes.…”

The effects of size changes on haptic object recognition

“…Distance cues and retinal size both contribute to the visually perceived size of an object (Haber & Levin, 2001); visual estimation of physical size occurs automatically (Goldfarb & Tzelgov, 2005) and begins in early visual cortex (Murray, Boyaci, & Kersten, 2006). However, whereas vision combines both direct, objectspecific cues and indirect, environmental cues, haptic size is normally perceived only through direct contact.…”

Distance perception in a natural outdoor setting: is there a developmental trend to overconstancy?

“…One of them was 14.7 × 13.0 cm (base × height) and was placed at physical distances of 1.0, 2.0, and 4.0 m; another was 19.0 × 17.0 cm, and was placed at 8.0 and 16.0 m; a third one was 52 × 45 cm, and was placed at 32.0 and 64.0 m; a fourth one was 59.5 × 52.0 cm, and was placed at 128.0 m; and the last one was 105.0 × 120.0 cm, and was placed at distances 256.0 and 296.0 m. These triangles were built following findings of Rozestraten and Da Silva (1977). Nevertheless, small differences in visual angles are not relevant to distance perception, either because of the absence of size constancy (Teghtsoonian & Beckwith, 1976), or because (egocentric) distance perception is considered an independent process of size perception (although the opposite is not true; that is, size perception requires knowing the egocentric distance to the perceived object) (Gogel, 1993;Haber & Levin, 2001).…”