Research supported by a Public Health Fellowship and by grant MR-11803-01 from the National Institute of Mental Health.

Research supported in part by National Institute of Mental Health Grant PN-8086, and presented in part at the 1967 American Psychological Association Convention.

Paper presented at the Merrill-Palmer Institute on Research and Training of Infant Development (Detroit, Mich., Feb. 15-17, 1968).

Eight autistic children and young adolescents (mean age 12.9 years) were compared to normal chronological age controls. Ss were required to discriminate briefly presented visual stimuli when they were preceded or followed by a visual noise mask and when they were not. The minimum stimulus exposure duration for criterion identification of unmasked…

This study examined the hypothesis that the effective visual field of 5-year-old children is smaller than that of 8-year-old children and adults. In addition, an effort was made to determine whether task demands affect the size of the effective visual field and if so, whether the effects on performance are different for children and adults. A…

Featured in this report is a summary of an extensive and unique study of color combinations and lighting. The summary presents the highlights of a report by Xr. Harry Helson which brings to fulfillment the complex work of this distinguished psychologist who began his inquiries in the late 50's. The report provides a method of forecasting whether a…

Experiments within the microgenetic paradigm provide an assessment of the role of stimulus structure and, inferentially, of cognitive structure on perception. Two experiments investigating the effect of redundancy (structure) in written language on visual perception are reported. Seven-letter arrays differing in percentage of redundancy were…

Eight sentences with high associative connections between their major elements (hi-m sentences) were generated from the Michigan Restricted Association Norms (Riegel, 1965a, b). Eight additional sentences with no or low association connections (lo-m sentences) were derived from the hi-m sentences by a scrambling procedure. All sentences were of…

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…

This study tested the hypothesis that newborns selectively orient toward angular elements in their visual field. Subjects were 36 awake and alert infants under 6 days of age. For each newborn, the study compared visual attention to three separately presented stimulus patterns: a complete outline triangle, only the sides of this triangle, and only…

Three procedures of the free-sort methodology which are usually standardized were varied in an attempt to discover the effects of such variation upon the number and nature of manifest categorizations. The conditions investigated were effectiveness of the sorting cue, the effects of the order of stimulus presentation and the effect of re-sorting.…