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D Diener

Publications and source records attributed to D Diener.

7 recordsLinked to original sources
PubMed1994

Effects of same-category and different-category extraneous memory sets on item recognition.

In a study designed to distinguish between parallel and serial models of performance on Sternberg's item recognition task, Krueger (1975) presented subjects with a memory set (the "added" set) followed by a second ("core") set, a probe to the core set, and finally a probe to the added set. Response latency (RT) to both the core- and added-set probes initially increased with the size of the extraneous set. Over successive blocks of trials, the effect of the size of the extraneous set diminished. In Experiment 1 of the present study, Krueger's basic procedures were replicated with results similar to those he reported for early trials. Experiment 2 was a variation on the added-set procedure. Rather than the memory sets' being drawn from different categories (letters and digits), both sets consisted of digits. On half of the negative trials for both the core and the added tasks, the probe was drawn from the extraneous set, forcing the subjects to separate the two sets. Although RT on the core task did not increase with the size of the added set, there was an increase in RT to the added set with increases in core-set size, a finding inconsistent with the serial search model.

Adolescent↗
PubMed1992

Cyclical variation in digit-span and visual-search performance in women differing in the severity of their premenstrual symptoms.

Groups of women differing in the severity of reported premenstrual symptoms were compared over two menstrual cycles on a digit-span task, a visual-search task, and a combination of the two. Neither group exhibited large performance changes during the premenstrual phase of the cycle. High-symptom women differed somewhat from low-symptom women in the effect of menstrual phase on digit-span performance, recalling slightly fewer series correctly during the premenstrual phase. The response latency of high-symptom women on the visual-search task was substantially longer than that of the low-symptom women regardless of menstrual phase. These results suggest that there may be stable differences between high-symptom and low-symptom subjects that are greater than the cyclical fluctuation within either group.

Adult↗
PubMed1990

Role of the preprobe delay in memory-scanning tasks.

In a variation of Sternberg's (1966, 1969) memory-scanning task not requiring an explicit negative response, Diener (1988) found that a preprobe delay was necessary to produce the usual set-size effect. In Experiment 1 of the present study, the effect of the preprobe delay was investigated in the typical two-response task. In the absence of a preprobe delay, the function relating response latency to set size was virtually flat for negative responses, but was described by a slope of about 18 msec/item for positive responses. Further research suggested that the reduced set-size effect in the absence of a preprobe delay is the result of expectancy effects usually controlled by the preprobe delay. Informing the subject of the size of the memory set before it was presented (Experiment 2) produced a set-size effect of the usual magnitude in the absence of a preprobe delay. Experiment 3 was designed to assess the effects of expectancy in the absence of a memory search. A task similar in stimulus arrangement to the memory-scanning task but requiring the subject to indicate whether the last digit in the set was odd or even produced a decrease in response latency with set size of 29 msec/item in the absence of a preprobe delay.

Adolescent↗
PubMed1990

The P&p illusion.

Identical letters can appear to differ in size and shape depending on whether they are interpreted as uppercase or lowercase. The effect is most-dramatic with the letter p. Examination of subjects' estimates of the magnitude of the effect for different stimuli suggests that two factors are involved in the illusion. One factor depends only on whether a letter is interpreted as uppercase or lowercase. This factor can be manipulated by changes in the size or case of the surrounding letters. The second factor, which depends on the possibility of interpreting a vertical line alternatively as an ascender or a descender (as in p or y), seems to involve a change in the perceived size of the letters' loops.

Adult↗