Evidence against a short-term-store account of long-term recency effects

When subjects perform a distractor task before and after every item on a list, recall of the last itemis much higher than recall of items from the middle of the list. Koppenaal and Glanzer (1990) have shown that this long-term recency effect can be eliminated by using, after the last item, a distractor task different from that used elsewhere on the list. They interpreted this finding as evidence in favor of a short-term-store account of long-term recency effects. This account is challenged by the results reported here. Practice either on the task or on time-sharing between the task and list items had little impact on the recency effect. Also, substantial recency effects were found when a different distractor task occurred after every list position. Thus, it is not true that long-term recency effects are found only when subjects have an opportunity to adapt to the distractor task. Our results are not consistent with a short-term-store account of recency effects.     

The Ranschburg effect: Stimulus variables and scoring criterion*

The influence of stimulus variables on recall of intraserially repeated items was investigated with a parametric manipulation of the rate of presentation (.4, .8, or 1.6 sec/item), modality of presentation (auditory or visual), and sequence length (7 or 10 items long). The results indicated that the Ranschburg effect, poorer recall of repeated items than of corresponding control items, is relatively insensitive to stimulus manipulations. The Ranschburg effect was found to be localized primarily at the position of the second occurrence of the repeated item. The influence of the repeated items did not generalize to the other (nonrepeated) items of the sequence. Differences in the Ranschburg effect as a function of the scoring criterion were discussed. The results were interpreted as being consistent with a guessing bias interpretation of the Ranschburg effect.     

Interresponse times in serial recall: effects of intraserial repetition

The authors examined the effects of intraserial repetition on multitrial serial learning of random consonant lists, analyzing both learning rates and perfect trial interresponse times (IRTs). Lists varied along 3 dimensions: list length, presence or absence of a repeated element, and lag between repeated elements. After achieving a forward-recall criterion on a given list, participants (N = 20) attempted backward recall. At small lags, IRTs between the repeated elements were very short (compared with IRTs from identical positions in nonrepetition lists). At larger lags, the IRT to recall the second repeated item was substantially longer than in control lists. These results reveal a latency analogue of the Ranschburg pattern seen in accuracy data. A Ranschburg pattern was also found in participants' learning rates. These results both generalize the Ranschburg phenomenon and present further challenges to theories of serial order memory.     

The Effects of Vocalisation on Situational Frequency Estimation

Two experiments are reported that studied the effects of vocalisation on situational frequency judgment. Subjects saw lists of words and were later asked to judge frequency of occurrence on the list. In Experiment 1, the word list was learned incidentally, and frequency estimates were higher for words that subjects had read aloud during study than for those that had been read silently. In Experiment 2, an intentional-learning procedure was used; higher estimates for words read aloud than for those read silently were found when pronunciation was manipulated within subjects but not when it was manipulated between subjects. In all cases, pronunciation had no effect on estimates for words that had only been presented once on the study list. These results suggest that multiple processes may underlie frequency estimation.     

The effect of prior recall on multiple response recognition

Certain investigators have found that recognition is impaired when a recall test is interpolated during the retention interval. One possible explanation of this finding is that interpolated recall leads subjects to employ a more stringent recognition criterion. In the two experiments reported here, the influence of the recognition criterion was eliminated by using a multiple-response test requiring subjects to rank a recognition list consisting of old and new items. Nevertheless recall impaired subsequent recognition in both experiments, the effect being most marked for lowly ranked items. The recognition test in the first experiment was carried out in two stages. This made possible a direct examination of whether recall has an effect on the recognition criterion. No evidence for such an effect was obtained. Other ways in which recall may affect the recognition criterion are discussed.     

Feelings of knowing in the Ranschburg effect

In two experiments, we assessed feelings of knowing (FOKs) for the Ranschburg effect to examine the types of retrieval ease that affect FOKs. In the Ranschburg effect, retrieval performance for repeated items differs from nonrepeated items in supramemory span tasks. We found that FOKs are affected by memory manipulations that affect recall processes, but not by manipulations that affect recognition. This suggests that processes that affect recognition, such as target familiarity, do not affect FOKs, whereas processes that affect recall, such as response suppression and guessing factors, affect FOKs. We propose that an integrated theory of FOKs must include mechanisms responsive to both encoding and retrieval factors (such as retrieval accessibility and cue familiarity), which are highly susceptible to output interference.     

The effects of noise on recall of lists of associated words

An experiment investigated the effect of noise on recall of lists consisting of pairs of strong and weak associates. Noise improved recall (both number recalled and organization of recall) and did so with both types of list. The subjects who were initially tested in noise continued to show better recall and organization of recall even when they were transferred to the quiet condition. This finding shows that noise may reinforce the use of the dominant strategy and that this strategy may be used more in noise when experimental conditions are changed and even when the subject is transferred from the noise to the quiet. This research was supported by a grant from the Social Science Research Council.     

The irrelevant sound effect under articulatory suppression is a suffix effect even with five-item lists

The relationship between the suffix effect and the effect of irrelevant sound on serial recall of auditorily presented lists is investigated in this study. Contrary to the predictions of the phonological loop model, Hanley and Hayes (2012) reported that the irrelevant sound effect was abolished under articulatory suppression when a spoken suffix was added at the end of the list. The experiment reported in this paper uses a shorter list length (five items per list) than that employed by Hanley and Hayes. This is because it cannot realistically be argued that participants will abandon the use of phonological codes to retain the list items with sequences as short as this. Results replicated those of Hanley and Hayes (2012). There was a significant effect of irrelevant sound under articulatory suppression when the list items were followed by an auditory tone. Crucially, however, the effect of irrelevant sound under articulatory suppression was abolished when the list items were followed by a spoken suffix.     

The irrelevant sound effect under articulatory suppression is a suffix effect even with five-item lists

The relationship between the suffix effect and the effect of irrelevant sound on serial recall of auditorily presented lists is investigated in this study. Contrary to the predictions of the phonological loop model, Hanley and Hayes (2012) reported that the irrelevant sound effect was abolished under articulatory suppression when a spoken suffix was added at the end of the list. The experiment reported in this paper uses a shorter list length (five items per list) than that employed by Hanley and Hayes. This is because it cannot realistically be argued that participants will abandon the use of phonological codes to retain the list items with sequences as short as this. Results replicated those of Hanley and Hayes (2012). There was a significant effect of irrelevant sound under articulatory suppression when the list items were followed by an auditory tone. Crucially, however, the effect of irrelevant sound under articulatory suppression was abolished when the list items were followed by a spoken suffix.     

Echoic memory and voice quality: Recency recall is not enhanced by varying presentation voice

Three experiments explored the effects on immediate recall of varying voice of presentation. Experiment 1 showed that the free-recall recency effect was not enhanced by presenting list words alternately in a male and a female voice. Experiment 2 replicated this result and also showed that recall of a given recency item from such a list was no more probable when the subjects were informed immediately following presentation that they need not recall the words presented in the other voice. Experiment 3 replicated previous findings of a reduction in the “suffix effect” when presentation voice is changed for the suffix item. The relation of this result to those of Experiments 1 and 2 is discussed.     

Creating False Memories of Words with or without Recognition of List Items: Evidence for Nonconscious Processes

Subjects exposed to lists of semantically related words falsely remember nonstudied words that are associated with the list items (e.g., Deese, 1959; Roediger & McDermott, 1995). To determine if subjects would demonstrate this false memory effect if they were unable to recognize the list items, we presented lists of semantically related words with or without a concurrent memory load at rates of 2 s, 250 ms, or 20 ms per word (Experiment 1, between-subjects design) and 2 s or 20 ms per word (Experiment 2, within-subjects design). We found that the subjects falsely recognized semantically related nonstudied words in all conditions, even when they were unable to discriminate studied words from unrelated nonstudied words. Recognition of list items was unnecessary for the occurrence of the false memory effect. This finding suggests that this memory illusion can be based on the nonconscious activation of semantic concepts during list presentation.     

Interrupting recognition memory: Tests of familiarity-based accounts of the revelation effect

The revelation effect is a puzzling phenomenon in which items on a recognition test are more likely to be judged as "old" when they are immediately preceded by a problem-solving task, such as anagram solution. The present experiments were designed to evaluate Westerman and Greene's (1998) and Hicks and Marsh's (1998) familiarity-based accounts of this effect. We found comparable revelation effects when probes were preceded by an anagram or a numerical addition task and when subjects performed either one or two of these tasks. Taken together, the results do not support familiarity-based accounts of the revelation effect but are consistent with a proposed decision-based interpretation (i.e., criterion flux), in which it is assumed that the revelation task displaces the study list context in working memory, leading subjects to adopt a more liberal recognition decision criterion, thereby increasing the hit and false alarm rates.     

Serial rote-learning: Incremental or all-or-none?

If the associative connections in a serial list are acquired in an all-or-none fashion, rather than gradually with every trial adding an increment of associative strength, then changing the serial order of the middle items in the list during the course of practice should have no effect on the rate of learning the list as a whole or even of the particular items that have been interchanged. Thirty subjects learned a serial list by the anticipation method. The middle items of the list were reversed in serial order approximately half-way through the number of trials required for mastery. The subjects took no longer to learn the list and made no more errors than did 30 control subjects for whom there was no change in serial order. The serial-position curves of the two groups were almost identical. It was also shown that the learning “curves” of single items in the series, when plotted for individual subjects do not reveal a gradually increasing probability of the correct response, but show instead a sudden jump on one trial from the chance guessing level to a level close to 100 per cent, correct responses. The results are consistent with a non-incremental theory of serial learning.     

The list length effect in recognition memory: an analysis of potential confounds

The list length effect in recognition memory refers to the finding that recognition performance for a short list is superior to that for a long list. The list length effect is consistent with the predictions of item noise models, but context noise models predict no effect. Recently, it has been argued that if potential confounds are controlled, the list length effect is eliminated. We report the results of two experiments in which we looked at the role of attention and the remember–know task in the detection of the list length effect. We conclude that there is no list length effect when potential confounds are controlled and that it is the design used to control for attention that is most vital.     

The effects of episodic and semantic memory on the identification of sentences masked by white noise

Two studies examine how episodic and semantic memory affect subjects’ abilities to repeat sentences masked by white noise. Subjects first hear a list of 70 sentences that are not masked. Subjects in the framework conditions are told prior to hearing the list that all sentences refer to a contextual framework concerning a deserted island. Subjects in the no-framework groups are not given this information. Subjects in the framework-after condition are given this information only after hearing the list of sentences. Subjects then perform a white-noise identification task. The results indicate that framework subjects are able to identify both old and new framework-related information better than other subjects. Subjects in the no-framework and framework-after conditions identify old information better than control subjects who do not participate in an acquisition phase. Emphasis is placed on the interdependence of episodic and semantic memory, including conditions leading to such interdependence.     

An adjacency effect in free recall

An adjacency effect was demonstrated at a high level of significance in the free recall, by 123 subjects, of a list of 40 high-frequency nouns presented in varying order on successive trials. The phenomenon referred to as the adjacency effect consists of the fact that when a subject is given repeated trials of study and free recall of a list of words (always presented in a different order), the probability of recalling a given item is greater when the item is presented temporally adjacent to an item which is already learned (as evidenced by recall on the previous trial) than when the item stands temporally between other items which are not yet learned. The enhancement of recall is greater when the item is presented between two previously learned items. The implications of the adjacency effect for verbal learning theory, particularly for the serial-position effect in serial learning and the concepts of interference and neural consolidation, are discussed.     

Effects of phonological similarity and concurrent irrelevant articulation on short-term-memory recall of repeated and novel word lists

The extent to which phonological similarity of list words impairs short-term-memory recall was investigated in two experiments. Experiment 1 showed that the phonological-similarity effect occurred both when list words were repeatedly sampled from a small set and when they were new on every trial, both when word-order information was required and when it was not. Furthermore, the adverse effect of phonological similarity on recall was apparent on the initial lists recalled, did not change over trials, and cannot be attributed to increasing levels of proactive inhibition across lists. In Experiment 2, subjects were required to count repeatedly to six during list presentation. Concurrent irrelevant articulation lowered recall and abolished the phonological similarity effect for both repeated and novel word lists.     

Position effects in comparative judgments of serial order: List structure vs. differential strength

Two experiments are reported that test the hypothesis that the serial position effect in comparative judgment of ordinal position in arbitrary serial lists results from differential memory or associative strength among list items. The serial position effect in comparative judgment is typically a pattern in which pairs that contain a term from one of the two extremes of the list are processed faster and more accurately than pairs that contain no end terms. The experiments show that a new term added to either the end or the middle of a well-practiced fourterm series behaves almost immediately like the end or central term, respectively, of a well-practiced five-term series. Furthermore, when the added term is removed, the list reverts immediately to the position effect obtained in a four-term series. Theories that explain the position effect by differential build-up of item strength or of interitem associative strength over practice cannot explain these effects. We propose instead that learning of a serial list is accomplished by assigning list members to positions in a general-purpose linear order schema and that subjects can make these assignments rapidly and flexibly.     

The stimulus suffix effect as a memory coding phenomenon

Two short-term memory experiments examined the nature of the stimulus suffix effect on auditory linguistic and nonlinguistic stimulus lists. In Experiment 1, where subjects recalled eight-item digit lists, it was found that a silently articulated digit suffix had the same effect on recall for the last list item as a spoken digit suffix. In Experiment 2, subjects recalled lists of sounds made by inanimate objects either by listing the names of the objects or by ordering a set of drawings of the objects. Auditory suffixes, either another object sound or the spoken name of an object, produced a suffix effect under both recall conditions, but a visually presented picture also produced a suffix effect when subjects recalled using pictures. The results were most adequately explained by a levels-of-processing memory coding hypothesis.     

The role of stimulus type in list length effects in recognition memory

While many studies have investigated the list length effect in recognition memory, few have done so with stimuli other than words. This article presents the results of four list length experiments that involved word pairs, faces, fractals, and photographs of scenes as the stimuli. A significant list length effect was identified when faces and fractals were the stimuli, but the effect was nonsignificant when the stimuli were word pairs or photographs of scenes. These findings suggest that the intrastimulus similarity is what dictates whether list length has a significant effect on recognition performance. As is the case with words, word pairs and photographs of scenes are not sufficiently similar to generate detectable item interference.