PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 8036122

How accurate is size and distance perception for very far terrestrial objects? Function and causality.

A Higashiyama·K Shimono
View original source ↗Export metadata ↓

Abstract

This study investigated absolute estimation of size and distance for natural and artificial objects at viewing distances of 1.1-15.3 km (Experiments 1 and 2) and 0.4-5.0 m (Experiment 3). The main results were that, regardless of distance range, size and distance estimates (S' and D') were related to objective size and distance (S and D), respectively, by a power function with an exponent of unity, but great individual differences in exponent were obtained for the far objects. The ratio S'/D' was reasonably represented by S'/D' = K theta n and S'/D' = tan(a theta +b), rather than S'/D' = tan theta, where theta is the visual angle. Partial correlations were obtained to examine whether (1) apparent size is determined by taking apparent distance into account or (2) both apparent size and apparent distance are determined directly by external stimuli. The combined data for the far objects and the data for the close objects showed that there were high correlations between S and S' and between D and D' and a low correlation between D' and S'. The data of Experiment 2 showed that both D' and S' were highly correlated with S, D, and theta, and there was a high positive correlation between D' and S'. It was suggested that the direct-perception model is valid under some situations, but the taking-into-account model is not supported in any set of data.

Explore related subjects

Distance PerceptionFemaleHumansMalePhotic StimulationSize PerceptionJournal Article

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A Higashiyama, K Shimono. 1994. How accurate is size and distance perception for very far terrestrial objects? Function and causality.. https://doi.org/10.3758/bf03205300

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Spatial and temporal properties of the illusory motion-induced position shift for drifting stimuli.

The perceived position of a stationary Gaussian window of a Gabor target shifts in the direction of motion of the Gabor's carrier stimulus, implying the presence of interactions between the specialized visual areas that encode form, position, and motion. The purpose of this study was to examine the temporal and spatial properties of this illusory motion-induced position shift (MIPS). We measured the magnitude of the MIPS for a pair of horizontally separated (2 or 8deg) truncated-Gabor stimuli (carrier=1 or 4cpd sinusoidal grating, Gaussian envelope SD=18arc min, 50% contrast) or a pair of Gaussian-windowed random-texture patterns that drifted vertically in opposite directions. The magnitude of the MIPS was measured for drift speeds up to 16deg/s and for stimulus durations up to 453ms. The temporal properties of the MIPS depended on the drift speed. At low velocities, the magnitude of the MIPS increased monotonically with the stimulus duration. At higher velocities, the magnitude of the MIPS increased with duration initially, then decreased between approximately 45 and 75ms before rising to reach a steady-state value at longer durations. In general, the magnitude of the MIPS was larger when the truncated-Gabor or random-texture stimuli were more spatially separated, but was similar for the different types of carrier stimuli. Our results are consistent with a framework that suggests that perceived form is modulated dynamically during stimulus motion.

Distance Perception↗
PubMed2006

[On the metric of visual space].

The major aim of this overview was the visual perception of egocentric (distance from an observer to a target) and exocentric distance (distance between two targets). We considered different issues concerning the relationship between perceived distance and physical distance, giving special attention to the theories, to the cues regarding distance, how perceived distances are measured, and the types of visual environments where the measuring of distances occurred. We concluded that the perceived distance does not reflect a simple transformation of its physical counterpart; rather, the mapping between perceived distance and physical distance depends substantially on the type of visual environments where distances are measured, and, on the cue combination available in these environments.

Distance Perception↗
PubMed2006

The impact of object size and rigidity on infant reaching.

Although the changes in kinematics of infant reaching have been studied, few researchers have investigated the improvement of reaching regarding objects of distinct physical properties. The aim of this longitudinal study was to verify the impact of object size and rigidity on the development of reaching in 4-6-month-old infants. Four infants were observed with a motion capture system during trials with four objects of distinct sizes and rigidity. A total of 188 reaches were analyzed by using the 3D movement reconstruction. Our results showed that reaching frequency, mean velocity, and straightness index increased with age. The number of movement units decreased with age and increased for small objects. Rigidity was not shown to affect reaching trajectories. These findings suggest that infants are capable of perceiving the more relevant object properties, thus using their available motor capabilities to modify the essential variables so that they can reach the target more accurately.

Distance Perception↗