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PubMed1977

Distance distortions in memory for spatial locations.

The present study examined developmental differences in the effect of route extensity on the memory for the locations of objects in a spatial array. Kindergarten and adult subjects were trained to remember the locations of 4 objects. During this training, objects were either connected by a combination of indirect, looped train tracks and direct train tracks (experimental subjects) or connected by entirely direct train-track routes (control subjects). Analyses of actual interobject distances, from subjects' reproductions of object locations on a response board (without train tracks), revealed that children, but not adults, distort distance in terms of the nature of travel observed between objects. Further testing revealed that differences in the amount of time taken for travel could not account for the results obtained with children.

Adult↗
PubMed1981

Maintenance of orientation during locomotion in unfamiliar environments.

Accuracy of maintenance of orientation during locomotion in unfamiliar environments was investigated by a laboratory procedure in two experiments. In a dark room, subjects were directed to a starting point, shown a target consisting of a point light on the floor, and required to walk straight by following a moving light line (1.18 m/sec) to a stopping point 1.4 to 11.0 m away. From the stopping point, the subjects numerically estimated the direction and distance to the target, which by then was out of sight. In contrast to control conditions with the target visible, the constant and variable errors were larger, and the constant errors varied with locomotion distance in a way that suggested proportional displacements of the target in the same direction as the subjects walked. Forgetting may in part account for the errors, but the main factor was assumed to be accumulated errors in recurrent central processing of the sensory information received about locomotion distance and target location.

Adolescent↗
PubMed1983

Spatial representation of maps.

Two experiments tested the hypothesis that the cognitive representation of spatial relations on a map is primarily a visually keyed process. In Experiment 1, undergraduates studied a labeled map where features were presented either as words alone, as mimetic drawings of the referent, or as geometric symbols. Cued recall data showed that discrete features are best located when they are semantically congruent with the label referent, a fact providing considerable support for the image position. Recognition testing required a set of introspective judgements ordinally related to the interfeature metric on the map. The judgment X distance estimates were highly correlated for all groups, intimating that a high correspondence exists between image distances and the original stimulus metric. Experiment 2 had undergraduates view either a full-scale or a three-quarter reduction of a reference map. Subjects in the reduced version were able to recognize significantly more interfeature comparisons, suggesting a predictable relation between visual and imaginal acuity. The judgement X distance results were essentially the same as in Experiment 1, and the two groups failed to differ in terms of cued recall. Data from both experiments imply that spatial relations are cognitively represented in at least a partially isomorphic fashion, which seems to possess quasi-pictorial qualities.

Cognition↗
PubMed1984

Influence of the target delay and duration on the prediction of a moving stimulus future position.

In a linear-motion prediction study an immobile target with different duration and delay with respect to the onset of the visible motion determined the motion extrapolation distance. The subject's task was to press a key at the moment when the moving stimulus would reach the position of the target if it continued its motion on the screen. The subject's response time was measured between the moment of the moving stimulus disappearance and the moment of key pressing. A linear relationship between the response time and the concealment time was obtained under all experimental conditions. It was demonstrated that the duration of the target did not affect the linear regression equation constants. The delay of the target presentation with respect to the onset of the visible motion was found to influence the free term of the linear relationship. When the target was presented with a great delay (0.56 s before the moving stimulus disappearance) the intercept in the linear relationship significantly decreased. The present results suggest that the organization of the response in the motion prediction conditions influences the temporal characteristics of the subject's performance. This influence is manifested in alternation of the free term in the linear relationship between the response time and concealment time.

Distance Perception↗
PubMed1978

Visually elicited finger movements in infants.

The relationship between visual stimulus intensity and finger movements was examined in infants from 10 to 15 weeks of age and from 20 to 25 weeks of age who were shown a cone that varied in size, brightness, and distance from them. 2 hypotheses derived from Schneirla's approach-withdrawal theory were examined; (1) that responses of the younger infants would be directly related to stimulus intensity, with finger extension (approach) movements elicited by weak stimuli and flexion (withdrawal) movements elicited by more intense stimuli; and (2) that stimulus dimensions such as distance, size, and brightness would make additive contributions to stimulus intensity, so that combinations of weak intensity would elicit finger extension and combinations of strong intensity would elicit flexion. Analyses of variance indicated no significant main effects of distance, size, or brightness, but significant age, intensity, and age x intensity effects. Older infants tended to extend their fingers more than younger infants. However, as intensity increased, the younger infants' responses showed decreases in extension and increases in flexion, while the older infants' responses indicated no clear relationship between intensity and response direction. That younger infants were responsive to the quantitative rather than the qualitative aspects of stimulation has important implications for understanding how various stimulus dimensions affect infant responses.

Age Factors↗
PubMed1983

The moon illusion revisited.

In two experiments, the apparent size of a simulated horizon moon was measured as a function of the location of visible texture in the natural vistas against which it appeared. Size was found to increase as the visible scene extended farther into the distance and to decrease as the moon rose above the vista of surface texture. In the second experiment, the observers' eye accommodation distances to various scenes were also measured with a laser optometer, and after appropriate transformations, size judgments were found to correlate 0.89 with measured accommodation values, thereby suggesting the hypothesis that the fabled moon illusion is mediated by the oculomotor adjustments of visual accommodation.

Accommodation, Ocular↗
PubMed1982

Psychophysical investigations of the temporal modulation sensitivity function in amblyopia: spatiotemporal interactions.

Temporal modulation sensitivity functions were measured in response to counterphase sine-wave gratings of various spatial frequencies in seven strabismic and/or anisometropic amblyopes and in two stimulus-deprivation amblyopes. Both movement/flicker and pattern detection thresholds were determined. Strabismic and/or anisometropic amblyopes showed reduced sensitivity for movement/flicker and pattern detection in the amblyopic eyes, which were dependent on both the spatial and temporal frequencies of the stimulus and the detection criterion. At medium and high spatial frequencies, substantial reductions in movement/flicker detection were present, which were generally more marked for low temporal modulation frequencies. Reductions in pattern sensitivity were greater at the higher spatial frequencies, although some amblyopes showed losses in sensitivity at low spatial frequencies as well. The losses observed in the spatiotemporal transfer function of the amblyopic eyes were greater than those found with unstructured stimuli (uniform field flicker) and were not eliminated under reduced luminance. In subjects with amblyopia caused by stimulus deprivation, losses in spatiotemporal contrast sensitivity were either invariant across temporal frequencies or increased at higher rates of temporal modulations.

Amblyopia↗
PubMed1982

Infants' sensitivity to familiar size as information for distance.

2 experiments tested the effectiveness of familiar size as information for perceived distance. In Experiment 1, under monocular viewing conditions, adults judged the distances to large and small (34.2 cm and 16.9 cm high) photographs of faces and to large and small checkerboard ovals equal to the faces in size. Familiar size influenced subjects' distance estimates. The small faces were judged to be more than twice the distance of the large faces. No significant difference was found between the judged distances to large and small checkerboards. In Experiment 2, the same displays were presented to 5- and 7-month-old infants. Faces were viewed either monocularly or binocularly; checkerboards were viewed monocularly. Duration of reaching was observed as a measure of perceived distance. 7-month-olds gave clear evidence of sensitivity to familiar size. In the monocular-face condition, the difference in duration of reaching to the large and small faces was significantly larger than in either the binocular-face condition or the monocular-checkerboard condition. This indicates that infants were not simply reaching to large faces or large objects without regard to spatial information. Rather, these results indicate that they perceived the large faces to be within reach and the small faces to be beyond reach in the monocular condition. 5-month-olds failed to provide evidence of sensitivity to familiar size.

Age Factors↗
PubMed1982

[The effects of familiar-size cue on children's judgments of size and distance].

The present study is concerned with the effects of familiar-size cue on the judgments of size and distance for the children of an elementary school. Thirty-two 1 st-, 3rd-, and 6 th-grade children served as subjects. The experiment consisted of repeating alternations of the two steps: A judgmental step in which the subject judged the size and distance of transparencies of familiar objects, and an informational step in which the subject was acquainted visually or haptically with the real sizes of a toy car and a toy dog from which the transparencies were made. The results revealed that: (1) The younger children tended to make judgments resulted from the normal sizes of the familiar objects that they encounter in their daily life, while the older children based their judgments on the size information given by looking on or touching the real toys. (2) Visual size information was superior to haptic size information both in size and distance judgments. (3) Familiar-size cue may be effective in relative rather than absolute size and distance judgments.

Child↗
PubMed1981

The effect of barriers on spatial representations.

48 first graders and 48 fifth graders learned the arrangement of 6 objects in a novel environment containing 2 large barriers. 3 nonoverlapping paths, each connecting all locations, were devised. Children were assigned to 4 experimental conditions representing the factorial combination of number of trials of walking (2 vs. 3) and path experience (same vs. different). Those in the same path-experience group walked the same path over trials, while those in the different path-experience group walked a different path on each trial. Following these walking experiences, the children used markers to reconstruct the environmental configuration from memory. Based on the interpoint distances calculated from these placements, the presence of barriers led to overestimations of distance only for those children who received less experience, which was distributed across a variety of paths (different path experience/2-trials group). These overestimations occurred primarily for barrier-present interpoint distances viewed but not directly walked. These results are discussed in terms of the opportunities for coordinating and integrating spatial perspectives provided by these environmental experiences.

Child↗