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P A Frensch

Publications and source records attributed to P A Frensch.

7 recordsLinked to original sources
PubMed1994

Composition during serial learning: a serial position effect.

Composition is a computational learning mechanism that merges serially performed elementary processes into hierarchically organized knowledge structures. The main goals of this research were to explore (a) the role of serial position in composition and (b) the relation between degree of composition and explicit serial recall in serial learning. In 3 experiments, Ss performed a rule-based serial reaction time task in which they had to categorize a sequence of 12 stimuli shown simultaneously on a video monitor. A procedure based on the comparison of reaction times to random sequences and a repeating sequence identified a serial position effect of composition that was, however, moderated by Ss' explicit, postexperimental recall of the repeating sequence. A production-system-based computational model of composition is described that qualitatively reproduces the empirical findings. Implications for the mechanisms governing serial learning are discussed.

Adolescent↗
PubMed1994

Effects of presentation rate and individual differences in short-term memory capacity on an indirect measure of serial learning.

In three experiments, we studied the relation between degree of implicit learning and two aspects of short-term memory: (1) the activation level of the to-be-learned information, and (2) individual differences in short-term memory capacity. In all the experiments, we used the Nissen and Bullemer (1987) serial reaction time paradigm or a modification thereof. The effects of activation level were assessed by experimentally manipulating the rate of presentation. Individual differences in short-term memory capacity were assessed via traditional span measures. The experiments demonstrated that the rate of presentation reliably affected an indirect measure of learning (i.e., response time) under both incidental and intentional task instructions and under both single-task and dual-task conditions. Short-term memory span was reliably related to the indirect measure of learning only in some experimental conditions. The findings represent important constraints for models of implicit serial learning and are discussed within a general framework for understanding implicit learning and memory.

Adolescent↗
PubMed1993

Effects of practice on component processes in complex mental addition.

Two experiments examined the effects of task practice on the speed of executing the component processes underlying the mental solution of complex addition problems. Componential analyses of Ss' response times in Experiment 1 demonstrated that the component process of carrying was reliably affected by amount of task practice. In contrast, the component processes of encoding single digits and of retrieving correct columnar answers from long-term memory appeared not to have been affected by amount of task practice. Computational feasibility checks indicated that the specificity of the practice effects could be explained by 2 distinct learning mechanisms: strengthening and composition. Results of Experiments 2A and 2B favor a composition explanation. We conclude that the differential practice effects in Experiment 1 are probably due to differential composition of component processes underlying complex mental addition.

Adolescent↗
PubMed1993

Simple and complex mental subtraction: strategy choice and speed-of-processing differences in younger and older adults.

Thirty-six younger adults (10 male, 26 female; ages 18 to 38 years) and 36 older adults (14 male, 22 female; ages 61 to 80 years) completed simple and complex paper-and-pencil subtraction tests and solved a series of simple and complex computer-presented subtraction problems. For the computer task, strategies and solution times were recorded on a trial-by-trial basis. Older Ss used a developmentally more mature mix of problem-solving strategies to solve both simple and complex subtraction problems. Analyses of component scores derived from the solution times suggest that the older Ss are slower at number encoding and number production but faster at executing the borrow procedure. In contrast, groups did not appear to differ in the speed of subtraction fact retrieval. Results from a computational simulation are consistent with the interpretation that older adults' advantage for strategy choices and for the speed of executing the borrow procedure might result from more practice solving subtraction problems.

Adult↗