List Members Research Articles

Recall as a Function of Input Clustering, Delay and Intentions to Learn

48 adults judged the similarity of word-pairs with (Intentional) and without (Incidental) knowledge that recall would follow. Pairs were typed next to each other (Simultaneous), or S turned a card to see the second member (Delayed). The list was composed of synonyms paired together (Synonymity), paired with themselves (Repeated), or paired with Unrelated list members. Recall for the Intentional Group was better clustered but not higher than for the Incidental Group. The Delayed Group recalled fewer words than the Simultaneous Group. Repeated and Unrelated pairings did not differ, and they produced lower recall than Synonymity pairings.

Cued and uncued free recall of unrelated words following interpolated learning.

.1 The 5s were given free-recall training to criterion with a list of 30 unrelated words, original learning (OL), were given seven trials with a second list, and were then tested for OL retention. Half of the 5s were cued with list members taken from alternate positions of the final recall of OL, half were not cued. Cued 5s retained significantly more critical items than did control 5s. Although similar results have been offered in support of the trace-dependent storage view, it was argued that such studies do not provide a differential test of independent vs. dependent storage. In two recent papers (Slamecka, 1968, 1969), it has been argued that in free-recall learning, memory traces for the words of the list are stored independently. Organization appearing in recall order is said to result from the use of an organized retrieval plan. In addition, the relative efficiency of such organized retrieval plans is assumed to produce the heightened recall usually associated with increases in recall organization. The alternative position is that organization takes place at the time of storage; i.e., that traces of list members are stored in some dependent fashion. According to this view, recall of one member of a set of relationally stored items (S unit) is assumed to cue recall of other items from the set. Thus, this trace-dependent storage hypothesis attributes both organization in recall order and concomitant increases in recall to organization in storage. Slamecka (1968, 1969) has argued that if, as indicated by the trace-dependent storage hypothesis, recall of one member of an S unit cues recall of the remaining members of that unit, then providing a member of that unit at the time of recall should have a similar effect. In a series of six experiments, Slamecka (1968) compared recall when some of the list members were provided as cues with recall when no such cues were provided. In none of these was cued recall found to be superior to uncued recall. In a subsequent series of experiments, Slamecka (1969) presented lists of unrelated words in constant serial order, cuing half of the 5s with words taken from odd-numbered serial positions in the presentation order. He again found the recall of cued 5s to be no greater than that of uncued controls. These findings were taken as evidence that item traces are not stored dependently. Subsequent investigators have pointed out that

Effect of cueing with list members in free recall as a function of number of categories, taxonomic frequency, and presentation order.

Effect of cueing with list members in free recall as a function of number of categories, taxonomic frequency, and presentation order.

Temporal Dating and Single-Trial Free Recall

The temporal dating (knowledge of an item's position in a list) of subjects who had been told they would be tested by free recall was then assessed by a reconstruction task, after they had received either one list or six. Other subjects were tested by free recall after the same amounts of practice. Free recall showed a drop in primacy with practice whereas reconstruction did not, which suggests that temporal tags per se may be relatively unimportant as retrieval cues for the recall of early list members.

Primacy effect in single-trial free recall

The primacy effect may be due to initial list members being relatively free of proactive inhibition (PI), spending longer time in a limited-capacity rehearsal buffer, or being associated with stronger retrieval cues. In three experiments using a single-trial free-recall procedure, S s were sometimes presented a forget cue during a list. The cue meant that they were not responsible for recalling any of the words which preceded it, only those which followed it. Since the primacy effect over the functional beginning of such lists was not diminished, the PI hypothesis was rejected. Tests of memory for list members which S s were under the impression they could forget showed consistently depressed retention of items immediately preceding a forget cue. This result was considered to be more in harmony with a rehearsal-buffer notion than a stronger-retrieval-cues position.

Subjective organization following constant input order in multitrial free recall

The present experiments were designed to assess the influence of consistent contiguous relations among list members on the development of subjective organization. One major source of contiguity experiences is provided by E’s arrangement of items during study trials. In the present experiments, recall following constant and varied input order was compared. Constant input order assures that the nominal input contiguity relations are consistent across trials. The results indicated that constant-input-order groups were superior to varied-input-order groups in terms of correct responses, subjective-organization scores, and input-order I output-order consistency scores.

Effect of simultaneous list presentation on paired-associate learning.

Difficulty of learning a list of 12 CVC pairs increased monotonically as a function of number of list items (1, 3, 6, and 12) grouped together for simultaneous exposure. Contrary to expectation, the difficulty was not affected by locus of grouping, i.e., whether grouping occurred on the study part, test part, or on both parts of each trial. Subsequent free recall also failed to show significant differences between conditions. The over-all grouping decrement was interpreted in terms of a strengthening of multiple associations among list members.

Proposed Plans for a Preliminary Sullivant Moss Society Check List of the Mosses of North America

There have been published two lists of the Mosses of North America, one by Rau & Hervey (188o) and the other by Cummings (1885). Both appeared many years ago and are probably now out of print. The writer is ready to help make up such a list and several members of the Society have agreed that a check list based on the arrangement of families, genera, and species as they appear in the 2nd edition of Engler and Prantl's Pflanzenfamilien, Volumes Io and ii, Musci I and Musci II, and printed as a supplement to THE BRYOLOGIST would be of great help to all the students of North American Mosses. To be worth while, this check list must be more than a compilation of the names that appear in Engler and Prantl's Pflanzenfamilien. For example, E. & P. lists many more species of Sphagnum for North America than are listed in Dr. Andrews' article on that group in the North American Flora. There are many places in the list of North American Mosses where the latest information on some groups or species does not exactly agree with the material as contained in Engler and Prantl's two volumes on Mosses, and all such differences should be adjusted before our own list is printed. Dr. Grout would be able to help on his special groups. Dr. Holzinger would know many names among the Acrocarpous groups that have perhaps been omitted from or not admitted to the pages of our standard work. Mrs. Britton would perhaps help with Fissidens and some other groups. Dr. Best would check the Thuidium group and nearby genera. Mr. Williams, Mr. Bartram, Miss Coker, Rev. H. Dupret, Dr. Nichols, and others would all be able to give valuable help on our proposed list. In fact our list must be a thoroughly American list and each species entry should be based on a known American specimen: i.e., collected within the boundaries of North America. No one should expect per fection in such a list as first printed, but after a period of years, a reprint of the list could be brought out that would approach more nearly that degree of accuracy which is essential in making a check list really valuable. Miss Haynes' recent list of Hepatics is a model for that group and if the Sullivant Moss Society members who are interested in Mosses can make the proposed moss list as attractive, useful, and accurate as the other list, we may all consider ourselves eligible to congratulations. Lists of the various groups of species are being compiled and will be sent to the several members who can check them, as rapidly as possible. In the meantime, suggestions for the successful outcome of our Society check list are asked for and will be thankfully received and carefully considered by the writer and a group of members whom we will call the Sullivant Moss Society Committee for printing The Check List of North American Mosses. NEW YORK CITY