Central scotomas--areas of the nonseeing retina within the central 20 degrees of the visual field--are present in approximately 90% of vision rehabilitation patients. They vary in size and shape and can be small or large, symmetrical or asymmetrical, round or irregularly shaped. Most central scotomas border fixation on one side and can be overcome…

DB, the first blindsight case to be tested extensively (Weiskrantz, 1986) has demonstrated the ability to detect and discriminate a range of visual stimuli presented within his perimetrically blind visual field defect. In a temporal two alternative forced choice (2AFC) detection experiment we have investigated the limits of DB's detection ability…

Examined acuity thresholds for 1- and 2-month-old infants by presenting square wave gratings in a preference paradigm at four viewing distances. (Author/JMB)

J. S. Joseph, M. M. Chun, and K. Nakayama (1997) found that pop-out visual search was impaired as a function of intertarget lag in an attentional blink (AB) paradigm in which the 1st target was a letter and the 2nd target was a search display. In 4 experiments, the present authors tested the implication that search efficiency should be similarly…

This study investigated whether the acuity threshold for distant targets is elevated for infants ranging in age from 24 to 63 days. Using square wave gratings and a modified staircase procedure, acuity thresholds for each of 331 infants were determined for one or more of the distances 30 cm, 60 cm, 90 cm and 150 cm. Acuity threshold was defined as…

A study involving two college students with visual impairments which made them incapable of accommodating visually revealed that Ss improved recognition efficiency with feedback but did not generalize the efficiency from trained to untrained stimuli of similar complexity. (CL)

A rather consistent finding in studies of perceived (imagined) compared to actual movement in a reaching paradigm is the tendency to overestimate at midline. Explanations of such behavior have focused primarily on perceptions of postural constraints and the notion that individuals calibrate reachability in reference to multiple degrees of freedom,…

Describes recent experiments at Cornell University; at schools in East Cleveland, Tennessee, North Carolina, and Kentucky; and at Middle Island School in Brookhaven, New York. (MLF)

Understanding vision is not a simple task. Nevertheless, a great deal is known about vision, more than about any of our other senses. The articles collected in this volume were chosen and organized with the intention of providing a survey of a number of different areas of vision research. Three major sections focus on the general categories of…

This study explores the reason why very young infants are unable to respond differentially to faces and the cause for developmental changes in infant face perception by age 3 months. Linear systems analysis (LSA) and the contrast sensitivity function (CSF) were used to estimate the facial pattern information available to 1- and 3-month-old…

Twenty-four congenitally visually handicapped infants, aged 6-24 months, participated in a study to determine (1) those stimuli best able to elicit visual attention, (2) the stability of visual acuity over time, and (3) the effects of binaural sensory aids on both visual attention and visual acuity. Ss were dichotomized into visually handicapped…

The authors present 10 experiments that challenge some central assumptions of the dominant theories of visual search. Their results reveal that the complexity (or redundancy) of nontarget items is a crucial but overlooked determinant of search efficiency. The authors offer a new theoretical outline that emphasizes the importance of nontarget…

Examined the stability of two aspects of infant visual attention derived from the paired-comparison procedure in infants tested at 6, 7, and 8 months of age. The two aspects were novelty preference and exposure time. Suggests that both novelty and exposure-time scores reflect moderately stable but independent characteristics of infant behavior.…

Finke and Kurtzman report that fields of resolution increase with increases in the diameter of both perceived and imagined circular patterns. In contrast, we find no such increase for imagined circular patterns when the experimenter is not aware of the experimental predictions, even though our subjects received imagery training. (Author/RD)