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D F Halpern

Publications and source records attributed to D F Halpern.

22 records · Page 2Linked to original sources
PubMed1983

Can age-related deficits in spatial memory be attenuated through the use of verbal coding?

In a sequential mental rotation task, women of three age groups (18-28, 50-60, and 70-80) viewed semi-abstract figures which were rotated in the picture plane. To investigate the effects of verbal mediation, each figure was presented under one of four labeling conditions. Errors increased as a function of age. Meaningful labels were beneficial in decreasing errors for the older subjects. Reaction time results generally replicated earlier studies, but there were indications that some women in the oldest group might have used strategies other than mental rotation. Results suggest that possible age related deficiencies in spatial abilities may be compensated for by greater use of verbal mediation.

Adolescent↗
PubMed1982

Subjective towers: depth relationships in multilevel subjective contours.

The perceived depth associated with subjective contours was studied with a three-level subjective contour configuration. An analysis of subjects' size judgments showed significant size-constancy scaling consistent with the prediction that subjects would perceive the various subjective surfaces as superimposed upon one another in depth. Direct depth estimations, however, showed only weak depth effects, easily reversed by conflicting depth cues, and observed with real, as well as subjective contours. The discrepant results point to the possibility of different functional depth cues for the two tasks. The order of tasks, indicative of priming, further suggested that depth processing may be secondary to pattern recognition rather than being causal in the formation of subjective contours.

Adult↗
PubMed1981

The determinants of illusory-contour perception.

The term 'illusory contours' refers to contours perceived where none physically exist. Three hypotheses that have been successful in their ability to account for this phenomenon invoke: (i) apparent depth; (ii) brightness contrast; and (iii) use of figural cues. An experiment has been designed to determine the extent to which each hypothesis accounts for the overall variation in subjects' responses to illusory contours when all three hypotheses are considered simultaneously. Experimental results suggest that different processes may assume a primary role in the perception of illusory contours depending upon the type of inducing area and the configuration. The results highlight the multifaceted nature of the processes involved, and indicate that no single theory can explain the perception of illusory contours.

Adolescent↗