Serial-Position Curve of Verbal Learning after Prolonged Practice

Abstract

This study investigated the effect of prolonged practice on the serial-position curve of learning. Thirteen Ss learned to a criterion of two perfect recitations by the anticipation method 12 different serial lists of 10 nonsense syllables, one list being learned each day. The hypothesis was that the skewness of the serial-position curve is produced by S's span of immediate memory. The prediction was that an increase in the memory span due to practice would cause an increase in the skewness of the serial-position curve. The skewness of the serial-position curve did increase with practice as predicted, but internal relations in the data implied a causal mechanism which was unrelated to memory span. Instead, Ss improved in the use of a strategy which employed the first serial item as an anchor item for directing learning.

Memory skill.

“…After 15 sessions, the study times for a list of 12 nonsense syllables were reduced by over 50% on the average and by over 85% for some individuals (Reed, 1917). For 10 nonsense syllable lists, Harcum and Coppage (1965) observed over 75% reduction of the number of errors prior to memorization during a 12-session period. Greater reduction was observed for two subjects given 30-40 practice sessions.…”

“…In accord with the studies of memory discussed earlier, skill improvements in memory through practice reflect storage in LTM. The improvements in learning rate are greater for the first half of the list (primacy effects) than for the second half of the list (recency effects) (Harcum & Coppage, 1965;Jensen & Roden, 1963;Lepley, 1934;Ward, 1937). Waugh (1960) found that the improved performance of well-practiced subjects occurred in the primacy portion of the serial position curve and that the recency portion was unaltered.…”

Explanation of serial learning errors within Deese-Kresse categories.

“…The second line of evidence against a span interpretation of the asymmetry follows a previous argument by Harcum and Coppage (1965), who used a method suggested by Jensen (1962a) to examine a diiierent aspect of serial learning data. Jensen plotted a so-called "order of learning" function based on the number of errors for each item, averaged across 6"s, but with items previously ranked for each .…”

“…The third question is whether the analysis of errors under paced and unpaced conditions supports the hypothesis that the serial position curve results from .SV strategies of acquiring items in consistent sequences (Coppage & Harcum, 1967;Harcum & Coppage, 1965;Jensen, 1962a). METHOD Deese and Kresse's (1952) conditions were closely duplicated, using CVC trigrams with associative values from 13% to 40% on Glaze's (1928) list.…”

“…The first question to be considered was whether the skewness in the FTR curve, and hence in the total distribution of errors, was imposed by a memory span for items at the beginning of the list. Although the argument for such an effect of memory span has received support (e.g., Feigenbaum & Simon, 1962;Jensen, 1962a), other data (e.g., Harcum & Coppage, 1965) has suggested a different ex-planation of asymmetry. Evidence on memory spans for various lengths of list should aid in answering this question.…”