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Concept: Serial position effect

150

In two studies, we examined Chinese students' memory for the names of the leaders of China. In Study 1, subjects were cued with the names of periods from China’s history. Subjects listed as many leaders as possible from each period and put them in the correct ordinal position when they could (see Roediger and DeSoto, 2014). Results showed that within each period, a primacy effect and sometimes a recency effect emerged. Moreover, the average recall probability for leaders within a specific period was a function of the ordinal position of the period. In Study 2, we asked another group of subjects to identify the sources through which they were able to recall each leader. We found that most subjects remembered leaders due to class and coursework. We also found a relation between a leader’s recall probability and the amount of information available on that leader on the Internet. Our findings further imply that the serial position function captures the form of collective memory.

Concepts: Internet, Period, Leadership, Learning, Sociology, Serial position effect

137

We examined how well typical adult listeners remember the speech of a person with a voice disorder (relative to that of a person without a voice disorder). Participants (n = 40) listened to two lists of words (one list uttered in a disordered voice and the other list uttered in a normal voice). After each list, participants completed a free recall test, in which they tried to remember as many words as they could. While the total number of words recalled did not differ between the disordered voice condition and the normal voice condition, an investigation of the serial-position curve revealed a difference. In the normal voice condition, a parabolic (i.e., u-shaped) serial-position curve was observed, with a significant primacy effect (i.e., the beginning of the list was remembered better than the middle) and a significant recency effect (i.e., the end of the list was remembered better than the middle). In contrast, in the disordered voice condition, while there was a significant recency effect, no primacy effect was present. Thus, the increased ability to remember the first words uttered by a speaker (relative to subsequent words) may disappear when the speaker has a voice disorder. Explanations and implications of this finding are discussed.

Concepts: The Normal, Oral communication, English-language films, Memory processes, Lists, List, Free recall, Serial position effect

28

There are innumerable demonstrations of serial position functions-with characteristic primacy and recency effects-in episodic tasks, but there are only a handful of such demonstrations in semantic memory tasks, and those demonstrations have used only two types of stimuli. Here, we provide three more examples of serial position functions when recalling from semantic memory. Participants were asked to reconstruct the order of (1) two cartoon theme song lyrics, (2) the seven Harry Potter books, and (3) two sets of movies, and all three demonstrations yielded conventional-looking serial position functions with primacy and recency effects. The data were well-fit by SIMPLE, a local distinctiveness model of memory that was originally designed to account for serial position effects in short- and long-term episodic memory. According to SIMPLE, serial position functions in both episodic and semantic memory tasks arise from the same type of processing: Items that are more separated from their close neighbors in psychological space at the time of recall will be better remembered. We argue that currently available evidence suggests that serial position functions observed when recalling items that are presumably in semantic memory arise because of the same processes as those observed when recalling items that are presumably in episodic memory.

Concepts: Procedural memory, Serial position effect, Declarative memory, Hippocampus, Episodic memory, Memory, Semantic memory, Harry Potter

2

The dynamic nature of human working memory, the general-purpose system for processing continuous input, while keeping no longer externally available information active in the background, is well captured in immediate free recall of supraspan word-lists. Free recall tasks produce several benchmark memory phenomena, like the U-shaped serial position curve, reflecting enhanced memory for early and late list items. To account for empirical data, including primacy and recency as well as contiguity effects, we propose here a neurobiologically based neural network model that unifies short- and long-term forms of memory and challenges both the standard view of working memory as persistent activity and dual-store accounts of free recall. Rapidly expressed and volatile synaptic plasticity, modulated intrinsic excitability, and spike-frequency adaptation are suggested as key cellular mechanisms underlying working memory encoding, reactivation and recall. Recent findings on the synaptic and molecular mechanisms behind early LTP and on spiking activity during delayed-match-to-sample tasks support this view.

Concepts: Working memory, Science, Synaptic plasticity, Storage, Serial position effect, Neuroscience, Memory, Memory processes

0

The well-known recency effect in immediate free recall reverses when subjects attempt to recall items studied and tested on a series of prior lists, as in the final-free-recall procedure (Craik, 1970). In this case, the last few items on each list are actually remembered less well than are the midlist items. Because dual-store theories of recall naturally predict negative recency, this phenomenon has long been cited as evidence favoring these models. In a final-free-recall study, we replicate the negative-recency effect for the within-list serial position curve and the positive-recency effect for the between-list serial position curve. Whereas we find prominent negative recency for items recalled early in the initial recall period, this effect is markedly reduced for items recalled later in the recall period. When considering initial recall as a second presentation of studied items, we find that the probability of final free recall increases as the number of items between initial presentation and initial recall increases. These results suggest that negative recency may reflect the beneficial effects of spaced practice, in which end-of-list items recalled early constitute massed repetitions and end-of-list items recalled late are spaced repetitions. To help distinguish between the spacing account and the prevailing dual-store, rehearsal-based account, we examined negative recency in continual-distractor free recall. Contrary to the dual-store account, but in accord with the spacing account, we find robust negative recency in continual-distractor free recall, which is greater for those items recalled early in output. (PsycINFO Database Record

Concepts: Space, Recall election, Memory processes, Free recall, Serial position effect

0

Three experiments examined whether or not benchmark findings observed in the immediate retrieval from episodic memory are similarly observed over much greater time-scales. Participants were presented with experimentally-controlled lists of words at the very slow rate of one word every hour using an iPhone recall application, RECAPP, which was also used to recall the words in either any order (free recall: Experiments 1 to 3) or the same order as presented (serial recall: Experiment 3). We found strong temporal contiguity effects, weak serial position effects with very limited recency, and clear list length effects in free recall; clear primacy effects and classic error gradients in serial recall; and recency effects in a final two-alternative forced choice recognition task (Experiments 2 and 3). Our findings extend the timescales over which temporal contiguity effects have been observed, but failed to find consistent evidence for strong long-term recency effects with experimenter-controlled stimuli.

Concepts: Amnesia, Hypothesis, Semantic memory, Procedural memory, Episodic memory, Memory, Hippocampus, Serial position effect

0

Recent theoretical accounts of verbal and visuo-spatial short-term memory (STM) have proposed the existence of domain-general mechanisms for the maintenance of serial order information. These accounts are based on the observation of similar behavioural effects across several modalities, such as temporal grouping effects. Across two experiments, the present study aimed at extending these findings, by exploring a STM modality that has received little interest so far, STM for musical information. Given its inherent rhythmic, temporal and serial organisation, the musical domain is of interest for investigating serial order STM processes such as temporal grouping. In Experiment 1, the data did not allow to determine the presence or the absence of temporal grouping effects. In Experiment 2, we observed that temporal grouping of tone sequences during encoding improves short-term recognition for serially presented probe tones. Furthermore, the serial position curves included micro-primacy and micro-recency effects, which are the hallmark characteristic of temporal grouping. Our results suggest that the encoding of serial order information in musical STM may be supported by temporal positional coding mechanisms similar to those reported in the verbal domain.

Concepts: Economics, Logic, Theory, Experiment, Scientific method, Serial position effect, Memory, Hypothesis

0

Three experiments examined the immediate free recall (IFR) of auditory-verbal and visuospatial materials from single-modality and dual-modality lists. In Experiment 1, we presented participants with between 1 and 16 spoken words, with between 1 and 16 visuospatial dot locations, or with between 1 and 16 words and dots with synchronized onsets. We found that for dual-modality lists (a) overall performance, initial recalls, and serial position curves were largely determined by the within-modality list lengths, (b) there was only a small degree of dual-task trade-off (that was limited to the visuospatial items), and © there were strongly constrained output orders: participants tended to alternate between words and dots from equivalent or neighboring serial positions. In Experiments 2 and 3, we compared lists of 6 single-modality items with dual-modality lists of 6 words and 6 dots with synchronous or alternating onsets (Experiment 2), or random but asynchronous onsets (Experiment 3). In all 3 dual-modality conditions, we again found only a small trade-off in visuospatial (but not verbal) IFR performance. There were similarly highly constrained output orders with the synchronous and alternating onsets, and these patterns were present but attenuated with the randomized onsets. We propose that both auditory-verbal and visuospatial list items are associated with a common temporal episodic context that is used to guide cross-modal retrieval, and we speculate that the limited, asymmetric interference could arise because the less variable representations of the dots share only a relatively small subset of features with the more variable representations of the words. (PsycINFO Database Record

Concepts: Dots, Experiment, Randomness, Economics, Serial position effect

0

This study investigated the effects of serial position and temporal distinctiveness on serial recall of simple visual stimuli. Participants observed lists of five colors presented at varying, unpredictably ordered interitem intervals, and their task was to reproduce the colors in their order of presentation by selecting colors on a continuous-response scale. To control for the possibility of verbal labeling, articulatory suppression was required in one of two experimental sessions. The predictions were derived through simulation from two computational models of serial recall: SIMPLE represents the class of temporal-distinctiveness models, whereas SOB-CS represents event-based models. According to temporal-distinctiveness models, items that are temporally isolated within a list are recalled more accurately than items that are temporally crowded. In contrast, event-based models assume that the time intervals between items do not affect recall performance per se, although free time following an item can improve memory for that item because of extended time for the encoding. The experimental and the simulated data were fit to an interference measurement model to measure the tendency to confuse items with other items nearby on the list-the locality constraint-in people as well as in the models. The continuous-reproduction performance showed a pronounced primacy effect with no recency, as well as some evidence for transpositions obeying the locality constraint. Though not entirely conclusive, this evidence favors event-based models over a role for temporal distinctiveness. There was also a strong detrimental effect of articulatory suppression, suggesting that verbal codes can be used to support serial-order memory of simple visual stimuli.

Concepts: Visual perception, Memory, Simulation, Photoreceptor cell, Effect, Recall election, Affect, Serial position effect

0

In 2 experiments, participants were presented with lists of between 2 and 12 words for either immediate free recall (IFR) or immediate serial recall (ISR). Auditory recall advantages at the end of the list (modality effects) and visual recall advantages early in the list (inverse modality effects) were observed in both tasks and the extent and magnitude of these effects were dependent upon list length. Both tasks displayed modality effects with short lists that were large in magnitude but limited to the final serial position, consistent with those observed in the typically short lists used in ISR, and both tasks displayed modality effects with longer lists that were small in magnitude and more extended across multiple end-of-list positions, consistent with those observed in the typically longer lists used in IFR. Inverse modality effects were also observed in both tasks at early list positions on longer lengths. Presentation modality did not affect where recall was initiated, but modality effects were greatest on trials where participants initiated recall with the first item. We argue for a unified account of IFR and ISR. We also assume that the presentation modality affects the encoding of all list items, and that modality effects emerge due to the greater resistance of auditory items to output interference. (PsycINFO Database Record

Concepts: Free group, Serial position effect, The Final, Length, Effect, Lists, Affect, List