Confirms that infants, like older children, are capable of responding categorically to stimuli of different shapes if these are similar in hue. (PCB)

This study examined relationships among lens color, visual grating, visual detection task performance, and peripheral retinal brightness thresholds among four adults and four children with reading disabilities and age-matched controls. Subjects with reading disabilities displayed significantly lower contrast sensitivity when tested with sine-wave…

In Experiment 1, 10 pigeons were exposed to a successive symbolic matching-to-sample procedure in which the sample was generated by the pigeons' own behavior. Each trial began with both response keys illuminated white, one being the "correct" key and the other the "incorrect" key. The pigeons had no way of discriminating which key was correct and…

In Experiment 1, we trained four pigeons to concurrently discriminate displays of 16 same icons (16S) from displays of 16 different icons (16D) as well as between displays of same icons (16S) from displays that contained 15 same icons and one different icon (15S:1D). The birds rapidly learned to discriminate 16S vs. 16D displays, but they failed…

In 7 experiments, the authors explored whether visual attention (the ability to select relevant visual information) and visual working memory (the ability to retain relevant visual information) share the same content representations. The presence of singleton distractors interfered more strongly with a visual search task when it was accompanied by…

A brief target that is visible when displayed alone can be rendered invisible by a trailing stimulus (metacontrast masking). It has been difficult to determine the temporal dynamics of masking to date because increments in stimulus duration have been invariably confounded with apparent brightness (Bloch's law). In the research reported here,…

In this study the authors address the issue of how the perceptual usefulness of nonliteral imagery should be evaluated. Perceptual performance with nonliteral imagery of natural scenes obtained at night from infrared and image-intensified sensors and from multisensor fusion methods was assessed to relate performance on 2 basic perceptual tasks to…

Six experiments investigated 7-month-old infants' capacity to learn about the self-propelled motion of an object. After observing 1 wind-up toy animal move on its own and a second wind-up toy animal move passively by an experimenter's hand, infants looked reliably longer at the former object during a subsequent stationary test, providing evidence…

Human neonates selectively fixated patterns with curved rather than straight contours when the outermost contours differed in this form variable and when quantitative variables were controlled. Data indicated the presence from birth of a discrimination ability basic to later form perception. (Author/ED)

The ability of 40 children four and five years of age to discriminate reflections and rotations of visual stimuli was examined in a kinetic imagery task. Results revealed that prediction accuracy was associated with the existence of orientation markers on the stimuli, as well as age, sex, type of discrimination, and several interactions among the…

Based on the author's master's thesis, University of Kansas, Kansas City, 1968. (JJ)

Investigates infants' scanning of two compound stimuli by presenting features (either squares or faces) inside a frame, the frame alone, and features alone. The apparent disappearance of external bias at about 21 months appears to apply to the scanning of only some compound figures. For schematic face figures, no external bias was found.…

Presents results of two experiments which measured contrast sensitivity function in infants. Information concerning development of visual acuity, low frequency attenuation, and sensitivity to contrast were collected. Results provide an approximate picture of and means for detection of infants' pattern information. (Author/DB)

In Experiment I, 24 preschoolers were tested on left-right, vertical-horizontal, and mirror-image oblique discriminations under essentially context-free conditions. Experiment II contrasted children's performance under context-free conditions with their ability to discriminate orientation in the presence of external visual cues. (RH)