The role of associative strength in the semantic relatedness effect on immediate serial recall

Semantic partitioning facilitates memory for object location through category-partition cueing

In our lived environments, objects are often semantically organised (e.g., cookware and cutlery are placed close together in the kitchen). Across four experiments, we examined how semantic partitions (that group same-category objects in space) influenced memory for object locations. Participants learned the locations of items in a semantically partitioned display (where each partition contained objects from a single category) as well as a purely visually partitioned display (where each partition contained a scrambled assortment of objects from different categories). Semantic partitions significantly improved location memory accuracy compared to the scrambled display. However, when the correct partition was cued (highlighted) to participants during recall, performance on the semantically partitioned display was similar to the scrambled display. These results suggest that semantic partitions largely benefit memory for location by enhancing the ability to use the given category as a cue for a visually partitioned area (e.g., toys - top left). Our results demonstrate that semantically structured spaces help location memory across partitions, but not items within a partition, providing new insights into the interaction between meaning and memory.

Semantic relatedness can impair memory for item locations

While memory for semantically related items is improved over unrelated items in many cases, relatedness can also lead to memory costs. Here we examined how the semantic relatedness of words within a display influenced memory for their locations. Participants learned the locations of words inside grid displays; the words in a given display were either from a single category or were from different assorted categories. When a display containing words from a single category was compared to a scrambled display containing words from multiple categories, location memory performance was rendered worse, while word recall performance was significantly improved. Our results suggest that semantically structured spaces can both help and harm memory within the context of a location memory task. We hypothesize that relatedness can improve memory performance by increasing the likelihood that matching candidates will be retrieved, yet might worsen performance that requires distinguishing between similar target representations.

Semantic partitioning facilitates memory for object location through category-partition cueing

In our lived environments, objects are often semantically organised (e.g., cookware and cutlery are placed close together in the kitchen). Across four experiments, we examined how semantic partitions (that group same-category objects in space) influenced memory for object locations. Participants learned the locations of items in a semantically partitioned display (where each partition contained objects from a single category) as well as a purely visually partitioned display (where each partition contained a scrambled assortment of objects from different categories). Semantic partitions significantly improved location memory accuracy compared to the scrambled display. However, when the correct partition was cued (highlighted) to participants during recall, performance on the semantically partitioned display was similar to the scrambled display. These results suggest that semantic partitions largely benefit memory for location by enhancing the ability to use the given category as a cue for a visually partitioned area (e.g., toys - top left). Our results demonstrate that semantically structured spaces help location memory across partitions, but not items within a partition, providing new insights into the interaction between meaning and memory.

The Semantic Similarity Effect on Short-Term Memory: Null Effects of Affectively Defined Semantic Similarity

Studies on short-term memory have repeatedly demonstrated the beneficial effect of semantic similarity. Although the effect seems robust, the aspects of semantics targeted by these studies (e.g., categorical structure, associative relationship, or dimension of meaning) should be clarified. A recent meta-regression study inspired by Osgood's view, which highlights affective dimensions in semantics, introduced a novel index for quantifying semantic similarity using affective values. Building on the results of the meta-regression of past studies' data with that index, this study predicts that semantic similarity is deleterious to short-term memory if it is manipulated by affective dimensions, after controlling for other confounding factors. This prediction was directly tested. The experimental results of the immediate serial recall task (Study 1) and immediate serial reconstruction of order task (Study 2) indicated null effects of semantic similarity by affective dimensions and thus falsified the prediction. These results suggest that semantic similarity based on affective dimensions is negligible.

Semantic Relatedness Effects in Serial Recall But Not in Serial Reconstruction of Order

Lists of semantically related words are better recalled than lists of unrelated words on immediate serial recall tests. Prominent explanations for this beneficial effect of semantic relatedness, such as the item/order hypothesis, invoke differential contributions of item and order information and predict that on tests that de-emphasize item information, the effect of semantic relatedness will be abolished. The prediction is hard to assess because previous studies using reconstruction of order tests show conflicting and equivocal results. Three experiments are reported that were designed to minimize problems associated with extant studies and that will allow reassessment of the prediction that semantic relatedness will have no effect on reconstruction of order tests. The experiments replicated the usual beneficial effect of semantic relatedness on memory when the test was serial recall but found no effect when the test was reconstruction of order. These results were observed regardless of whether semantic relatedness was defined by category membership (Experiment 1), association (Experiment 2), or meaning (Experiment 3). These results clarify earlier results in the literature and confirm a strong prediction of the item/order hypothesis.

Calculating semantic relatedness of lists of nouns using WordNet path length

Lists of semantically related words are better recalled on immediate memory tests than otherwise equivalent lists of unrelated words. However, measuring the degree of relatedness is not straightforward. We report three experiments that assess the ability of various measures of semantic relatedness-including latent semantic analysis (LSA), GloVe, fastText, and a number of measures based on WordNet-to predict whether two lists of words will be differentially recalled. In Experiment 1, all measures except LSA correctly predicted the observed better recall of the related than the unrelated list. In Experiment 2, all measures except JCN predicted that abstract words would be recalled equally as well as concrete words because of their enhanced semantic relatedness. In Experiment 3, LSA, GLoVe, and fastText predicted an enhanced concreteness effect because the concrete words were more related; three WordNet measures predicted a small concreteness effect because the abstract and concrete words did not differ in semantic relatedness; and three other WordNet measures predicted no concreteness effect because the abstract words were more related than the concrete words. A small concreteness effect was observed. Over the three experiments, only two measures, both based on simple WordNet path length, predicted all three results. We suggest that the results are not unexpected because semantic processing in episodic memory experiments differs from that in reading, similarity judgment, and analogy tasks which are the most common way of assessing such measures.

Re-assessing age of acquisition effects in recognition, free recall, and serial recall

Age of acquisition (AoA) refers to the age at which a person learns a word. Research has converged on the conclusion that early AoA words are processed more efficiently than late AoA words on a number of perceptual and reading tasks. However, only a few studies have investigated whether AoA affects memory on recognition, serial recall, and free recall tests, and the results are equivocal. We took advantage of the recent increase in the number of high-quality norms and databases to construct a pool of early and late AoA words that were equated on numerous other dimensions. There was a late AoA advantage in recognition using both pure (Experiment 1) and mixed (Experiment 2) lists, no effect of AoA on serial recall of either pure (Experiment 3) or mixed (Experiment 4) lists, and no effect of AoA on free recall of either pure (Experiment 5) or mixed lists (Experiment 6). We conclude that AoA does reliably affect memory on some memory tasks (recognition), but not others (serial recall, free recall), and that no current account of AoA can explain the findings.

The detrimental effect of semantic similarity in short-term memory tasks: A meta-regression approach

The literature suggests that semantic similarity has a weak or null effect for immediate serial reconstruction and a facilitative effect for immediate serial recall. These observed semantic similarity effects are inconsistent with the assumptions of short-term memory (STM) models on the detrimental effect of similarity (e.g., confusion) and with observations of a robust detrimental effect of phonological similarity. Our review indicates that the experimental results are likely dependent on the manipulation strength for semantic similarity and that manipulations used in previous studies might have affected semantic assvociation as well as semantic similarity. To address these possible issues, two indices are proposed: (a) strength of manipulation on semantic similarity, gained by quantifying semantic similarity based on Osgood and associates' dimensional view of semantics, and (b) inter-item associative strength, a possible confounding factor. Our review and the results of a meta-regression analysis using these two indices suggest that semantic similarity has a detrimental effect on both serial reconstruction and serial recall, while semantic association, which is correlated with semantic similarity, contributes to an apparent facilitative effect. An effect that is not attributable to similarity or association was also implied. Review on item and order memory further suggests the facilitative effect of semantic association on item memory and the detrimental effect of the semantic similarity on order memory. Based on our findings, we propose a unified explanation of observations of semantic similarity effects for both serial reconstruction and serial recall that is in good accord with STM models.

Explaining short-term memory phenomena with an integrated episodic/semantic framework of long-term memory

Current thinking about human memory is dominated by distinctions between episodic and semantic memory and between short-term memory (STM) and long-term memory (LTM). However, many memory phenomena seem to cut across these distinctions. This article attempts to set the groundwork for the issues that need to be resolved in generating an integrated model of long-term memory that incorporates semantic, episodic, and short-term memory. We contrast Nairne's (2002, Annual Review of Psychology) consensus account of short-term memory with a relatively generic theory of an integrated episodic-semantic memory. The later consists primarily of a list of principles which we and others argue are necessary to include in any theory of long-term memory. We then add some more specific assumptions to outline a modern theory of forgetting. We then turn to the issue of much of the phenomena thought to necessitate a dedicated short-term memory can be explained by an integrated theory of episodic and semantic memory. Our conclusion is that an integrated theory of long-term memory must be augmented to explain a small number of outstanding memory phenomena. Finally, we ask whether the augmentation needs to involve a dedicated mnemonic system, or sensory or language-based systems, which also have mnemonic capabilities.

Domain-Generality of Timing-Based Serial Order Processes in Short-Term Memory: New Insights from Musical and Verbal Domains

Several models in the verbal domain of short-term memory (STM) consider a dissociation between item and order processing. This view is supported by data demonstrating that different types of time-based interference have a greater effect on memory for the order of to-be-remembered items than on memory for the items themselves. The present study investigated the domain-generality of the item versus serial order dissociation by comparing the differential effects of time-based interfering tasks, such as rhythmic interference and articulatory suppression, on item and order processing in verbal and musical STM domains. In Experiment 1, participants had to maintain sequences of verbal or musical information in STM, followed by a probe sequence, this under different conditions of interference (no-interference, rhythmic interference, articulatory suppression). They were required to decide whether all items of the probe list matched those of the memory list (item condition) or whether the order of the items in the probe sequence matched the order in the memory list (order condition). In Experiment 2, participants performed a serial order probe recognition task for verbal and musical sequences ensuring sequential maintenance processes, under no-interference or rhythmic interference conditions. For Experiment 1, serial order recognition was not significantly more impacted by interfering tasks than was item recognition, this for both verbal and musical domains. For Experiment 2, we observed selective interference of the rhythmic interference condition on both musical and verbal order STM tasks. Overall, the results suggest a similar and selective sensitivity to time-based interference for serial order STM in verbal and musical domains, but only when the STM tasks ensure sequential maintenance processes.

Novel word acquisition in aphasia: Facing the word-referent ambiguity of natural language learning contexts

Recent research suggests that some people with aphasia preserve some ability to learn novel words and to retain them in the long-term. However, this novel word learning ability has been studied only in the context of single word-picture pairings. We examined the ability of people with chronic aphasia to learn novel words using a paradigm that presents new word forms together with a limited set of different possible visual referents and requires the identification of the correct word-object associations on the basis of online feedback. We also studied the relationship between word learning ability and aphasia severity, word processing abilities, and verbal short-term memory (STM). We further examined the influence of gross lesion location on new word learning. The word learning task was first validated with a group of forty-five young adults. Fourteen participants with chronic aphasia were administered the task and underwent tests of immediate and long-term recognition memory at 1 week. Their performance was compared to that of a group of fourteen matched controls using growth curve analysis. The learning curve and recognition performance of the aphasia group was significantly below the matched control group, although above-chance recognition performance and case-by-case analyses indicated that some participants with aphasia had learned the correct word-referent mappings. Verbal STM but not word processing abilities predicted word learning ability after controlling for aphasia severity. Importantly, participants with lesions in the left frontal cortex performed significantly worse than participants with lesions that spared the left frontal region both during word learning and on the recognition tests. Our findings indicate that some people with aphasia can preserve the ability to learn a small novel lexicon in an ambiguous word-referent context. This learning and recognition memory ability was associated with verbal STM capacity, aphasia severity and the integrity of the left inferior frontal region.

Item-properties may influence item-item associations in serial recall

Attributes of words, such as frequency and imageability, can influence memory for order. In serial recall, Hulme, Stuart, Brown, and Morin (Journal of Memory and Language, 49(4), 500-518, 2003) found that high-frequency words were recalled worse, and low-frequency words better, when embedded in alternating lists than pure lists. This is predicted by associative chaining, wherein each recalled list-item becomes a recall-cue for the next item. However, Hulme, Stuart, Brown, and Morin (Journal of Memory and Language, 49(4), 500-518, 2003) argued their findings supported positional-coding models, wherein items are linked to a representation of position, with no direct associations between items. They suggested their serial-position effects were due to pre-experimental semantic similarity between pairs of items, which depended on frequency, or a complex tradeoff between item- and order-coding (Morin, Poirier, Fortin, & Hulme, Psychonomic Bulletin Review, 13(4), 724-729, 2006). We replicated the smooth serial-position effects, but accounts based on pre-existing similarity or item-order tradeoffs were untenable. Alternative accounts based, on imageability, phonological and lexical neighbourhood sizes were also ruled out. The standard chaining account predicts that if accuracy is conditionalized on whether the prior item was correct, the word-frequency effect should reappear in alternating lists; however, this prediction was not borne out, challenging this retrieval-based chaining account. We describe a new account, whereby frequency influences the strengths of item-item associations, symmetrically, during study. A manipulation of word-imageability also produced a pattern consistent with item-item cueing at study, but left room for effects of imageability at the final stage of recall. These findings provide further support for the contribution of associative chaining to serial-recall behaviour and show that item-properties may influence serial-recall in multiple ways.

The effects of mindfulness-based cognitive therapy on affective memory recall dynamics in depression: a mechanistic model of rumination

OBJECTIVES

converging research suggests that mindfulness training exerts its therapeutic effects on depression by reducing rumination. Theoretically, rumination is a multifaceted construct that aggregates multiple neurocognitive aspects of depression, including poor executive control, negative and overgeneral memory bias, and persistence or stickiness of negative mind states. Current measures of rumination, most-often self-reports, do not capture these different aspects of ruminative tendencies, and therefore are limited in providing detailed information about the mechanisms of mindfulness.

METHODS

we developed new insight into the potential mechanisms of rumination, based on three model-based metrics of free recall dynamics. These three measures reflect the patterns of memory retrieval of valenced information: the probability of first recall (Pstart) which represents initial affective bias, the probability of staying with the same valence category rather than switching, which indicates strength of positive or negative association networks (Pstay), and probability of stopping (Pstop) or ending recall within a given valence, which indicates persistence or stickiness of a mind state. We investigated the effects of Mindfulness-Based Cognitive Therapy (MBCT; N = 29) vs. wait-list control (N = 23) on these recall dynamics in a randomized controlled trial in individuals with recurrent depression. Participants completed a standard laboratory stressor, the Trier Social Stress Test, to induce negative mood and activate ruminative tendencies. Following that, participants completed a free recall task consisting of three word lists. This assessment was conducted both before and after treatment or wait-list.

RESULTS

while MBCT participant's Pstart remained relatively stable, controls showed multiple indications of depression-related deterioration toward more negative and less positive bias. Following the intervention, MBCT participants decreased in their tendency to sustain trains of negative words and increased their tendency to sustain trains of positive words. Conversely, controls showed the opposite tendency: controls stayed in trains of negative words for longer, and stayed in trains of positive words for less time relative to pre-intervention scores. MBCT participants tended to stop recall less often with negative words, which indicates less persistence or stickiness of negatively valenced mental context.

CONCLUSION

MBCT participants showed a decrease in patterns that may perpetuate rumination on all three types of recall dynamics (Pstart, Pstay, and Pstop), compared to controls. MBCT may weaken the strength of self-perpetuating negative associations networks that are responsible for the persistent and "sticky" negative mind states observed in depression, and increase the positive associations that are lacking in depression. This study also offers a novel, objective method of measuring several indices of ruminative tendencies indicative of the underlying mechanisms of rumination.

Revisiting backward recall and benchmark memory effects: a reply to Bireta et al. (2010)

When participants are asked to recall lists of items in the reverse order, known as backward recall, several benchmark memory phenomena, such as the word length effect, are abolished (Bireta et al. Memory & Cognition 38:279-291, 2010). Bireta et al. (Memory & Cognition 38:279-291, 2010) suggested that in backward recall, reliance on order retention is increased at the expense of item retention, leading to the abolition of item-based phenomena. In a subsequent study, however, Guérard and Saint-Aubin (in press) showed that four lexical factors known to modulate item retention were unaffected by recall direction. In a series of five experiments, we examined the source of the discrepancy between the two studies. We revisited the effects of phonological similarity, word length, articulatory suppression, and irrelevant speech, using open and closed pools of words in backward and forward recall. The results are unequivocal in showing that none of these effects are influenced by recall direction, suggesting that Bireta et al.'s (Memory & Cognition 38:279-291, 2010) results are the consequence of their particular stimuli.

The effect of semantic relatedness on immediate serial recall and serial recognition

The present study examined the effects of semantic relatedness on immediate serial recall and serial recognition. Each participant received either blocked or randomly intermixed serial recall or serial recognition trials. Replicating the findings of previous studies (e.g., Saint-Aubin, Ouellette, & Poirier, 2005), semantic relatedness boosted percentage serial recall but also increased order errors, after taking into account the proportion of correctly recalled items, regardless of their orders, in serial recall trials. In serial recognition trials, participants' responses were slower and less accurate for related lists than for unrelated lists. There were intraindividual correlations among order memory measures in serial recall versus serial recognition trials. The implications of these findings for item redintegration theories are discussed.