Beyond resources - formal models for complexity effects and age differences in working memory. Primary data of the memory updating experiment.

Research Questions/Hypotheses:

With increasing loads on working memory and old age the asymptotic accuracy in the time-accuracy functions and the rate of approach to the asymptote decrease.

Research Design:

Experimental Design, Quasi-experimental Design, Mixed Design, Laboratory Experiment; repeated measurements

Measurement Instruments/Apparatus:

A computer monitor displayed single digits that were presented on a circularly arranged frame and which varied depending on memory load, (Experiment 1: n = 1-4, Experiment 2: n = 4-6). After the first few digits disappeared, arithmetic operations were presented in the same context (for n = 1, the performance of arithmetic operations was also presented in 2 frames). The arithmetic operations were applied to the number of the corresponding frame. After 8 arithmetic operations, the frames were tagged in random order by question marks. The subjects then had to enter the corresponding result on the keyboard.
Subjects were informed that all the results and all intermediate values would be between 1-9. After 3,000 msec for the young and 5,000 msec was for the old subjects the words “too slow” instead of “right” or “wrong” were shown to avoid drawn out calculations. Subjects were also told that only trials with correct responses in all the frames would count in order to discourage focusing on one frame too long. Complexity (number of digits to be remembered) was varied and balanced across blocks of 13 attempts. For each condition, 234 runs were performed. The presentation times for the arithmetic operations were adaptively varied from passage to passage so that they measured the area between random asymptotic accuracy of per condition. After 10 blocks, this adaptive algorithm was replaced by a “filler” algorithm in order to obtain at least 10 data points for each category. The individual tasks were generated randomly.

Data Collection Method:

Data collection in the presence of an experimenter

• Individual administration
• Computer-supported

Population:

Young vs. old adults

Survey Time Period:

1996, Experiment 2 was conducted approx. 6 months after experiment 1

Sample:

Convenience sample

Gender Distribution:

52,8% female subjects (n=19)
47,2% male subjects (n=17)

Age Distribution: 18-21; 65-80 years

Spatial Coverage (Country/Region/City): Germany/Brandenburg/Potsdam

Subject Recruitment:

The young subjects, all secondary school students, were recruited from the Potsdam participant pool. The old subjects were recruited through newspaper advertisements or were friends or relatives of other participants. Participants received 15 DM for a 1-hour session.

Sample Size:

36 individuals

Return/Drop Out:

3 subjects from Experiment 1 could not be re-recruited for Experiment 2.