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C T Scialfa

Publications and source records attributed to C T Scialfa.

25 records · Page 2Linked to original sources
PubMed1986

Age differences in the commonality of free associations.

Commonality of associative response provides an index of the organization of semantic memory. The present study investigated age differences in semantic organization by comparing commonality of associative response. Thirty young (M = 20 yrs) and 30 old (M = 72 yrs) adults gave free associations to single stimulus words of high or low linguistic frequency. Controlling statistically for education and verbal skills, it was determined that there were no age differences in the commonality or variability of associates. Results are discussed in reference to developmental trends in the organization of semantic memory.

Adolescent↗
PubMed1984

Age differences in Wechsler Memory Scale performance.

Calculated mean scores for older persons utilizing data from previous studies that measured Wechsler Memory Scale performance in healthy samples and compared with those of younger adults and a sample of neurologically impaired aged (N = 384). Statistical analysis indicated that in total raw scores, as well as in all subtest scores but Digit Span, there are significant differences in the performance of different age groups. The degree to which age is associated with subtest performance varies depending on the particular subtest involved. Results are discussed in terms of their clinical implications and current theories of aging and memory.

Adult↗
PubMedDate not supplied

Aging, texture segmentation, and exposure duration: evidence for a deficit is preattentive processing.

Younger and older observers were asked to detect the presence and identify the orientation of an orientation-based texture target presented at durations ranging from 15 to 75 ms. In Experiment 1a, an age by duration interaction indicated that older adults were less able to process the displays at short durations. In Experiment 1b, a group of younger adults was given the task under conditions designed to simulate age-related changes in retinal illuminance. Their performance was independent of luminance, and was still superior to that of older adults in Experiment 1a. Several mechanisms are potential contributors to these age deficits in lower-level processing that can influence higher-level visual perception.

Adolescent↗
PubMedDate not supplied

Age differences in feature search as a function of exposure duration.

Older and younger observers searched for two targets embedded in response-compatible or -incompatible distractors. Display duration was varied across trial blocks from 26 to 1,664 ms. For both age groups, response-incompatible displays led to relatively poorer accuracy, particularly at brief durations. Age differences in accuracy were larger for response-incompatible displays and diminished at longer durations, an effect that was also revealed in the latency data. Results are interpreted within a continuous-flow conceptualization of visual processing and are consistent with the hypothesis that older adults are slowed in the feature extraction process that underlies visual search.

Adolescent↗
PubMedDate not supplied

Age, target-distractor similarity, and visual search.

Younger and older adults were asked to find a single target in both feature- and conjunction- search conditions. Display size varied between 2 and 8 items, and target-distractor similarity ranged from relatively low to high levels. The accuracy data indicated that older adults had particular difficulty finding targets in high-similarity conjunction-search displays containing a large number of distractors. The reaction time (RT) analyses found larger age deficits in many of these same conditions. For both groups, predictions of conjunction search based on Treisman and Sato's additive model (Journal of Experimental Psychology: Human Perception and Performance, 1990: 16, 459-478) departed significantly from actual performance. The RT data of older observers were, in large part, predicted as a simple linear function of the young adults' data. These results are discussed with respect to age differences in selective attention, generalized slowing, and an age-related loss in search efficiency.

Adolescent↗
PubMedDate not supplied

Age differences in the temporal continuity of gratings as a function of their spatial frequency.

This study compared young and elderly observers on the continuity of sinusoidal grating-pairs as a function of interstimulus interval (ISI) and spatial frequency (.5, 1.0, 2.0, 4.0, 8.0, and 12.0 c/deg). Consistent with prior research, the maximum ISI over which pattern continuity was maintained increased with spatial frequency. In addition, among older observers, grating continuity occurred at significantly longer ISI's at the two lowest spatial frequencies; no age difference was observed at the higher spatial frequencies. These results could not be attributed to an age difference in retinal illumination associated with pupillary miosis. However, they do indicate an age-related decline in detecting visual offset and are consistent with the hypothesis of a decline in the effectiveness of the transient visual channels.

Adolescent↗