Investigating the roles of phonological and semantic memory in sentence recall

The mechanisms underlying short-term sentence recall have been the subject of recent investigations. While both semantic and phonological information have been found to play a role in sentence recall, this has been established using different paradigms in previous research. As a result, it is not clear whether the contributions of semantic and phonological information are equivalent subject only to specific experimental conditions. The present study used a common paradigm with equally plausible lures to systematically compare the roles of semantic and phonological information in short-term sentence recall. The lure intrusion paradigm was used with three different lures that were all equally plausible in the context of the sentence: semantic, onset, and rhyme. Further, no contextual cues were provided in the sentence to bias the participant. The findings indicate that there were significantly more semantic and onset intrusions compared to rhyme intrusions. This is interpreted in light of models incorporating lexical information during sentence production.     

Presentation duration and false recall for semantic and phonological associates

Two experiments examined false recall for lists of semantically and phonologically associated words as a function of presentation duration. Veridical recall increased with long exposure durations for all lists. For semantically associated lists, false recall increased from 20-250 ms, then decreased. There was a high level of false recall with 20 ms durations for phonologically associated lists (47 and 44% for Experiments 1 and 2, respectively), which declined as duration increased. In Experiment 2, for lists presented at 20 and 50 ms rates, false recall given zero correct recall was observed frequently, suggesting that conscious recollection of studied words was not necessary for phonological false memory. Differences between phonologically and semantically associated lists were consistent with a feature integration model based on automatic initial processing of phonetic features of words.     

Imagery effects and semantic similarity in sentence recognition memory

The idea that subjects often use imagery to discriminate semantically similar sentences was tested in three experiments. In the first experiment, subjects heard subject-verb-object sentences in the context of either a comprehension task or an image-generation task. Their memory for the sentences was tested using a two-alternative forced-choice recognition test in which different types of distractor sentence were used. A sentence semantically similar to the target sentence was one type; a sentence with the same subject and object nouns as the target sentence, but dissimilar in meaning, was another type; and a sentence similar in meaning to one of the stimulus sentences, but not to the target sentence, was a third type. The results showed that the image-generation instructions enhanced later recognition performance, but only for semantically similar test items. A second experiment showed that this finding only holds for high-imagery sentences containing concrete noun concepts. A third experiment demonstrated that the enhanced recognition performance could not be accounted for in terms of a semantic model of test-item discrimination. Collectively, the results were interpreted as providing evidence for the notion that subjects discriminate the semantically similar test items by elaborating the sentence encoding through image processing.     

Investigating the interplay between semantic and phonological distractor effects in picture naming

In this paper, we investigate the interplay between phonological facilitation and semantic interference effects in picture naming. We use a double distractor variant of the classic picture-word interference paradigm to investigate whether the reported interaction between these effects is dependent on the two types of related information being presented by the same distractor word or not. While prior studies using single mixed distractors such as pigeon for the target PIG have reported an interaction between phonological facilitation and semantic interference, we find additivity when the two types of related information come from two different distractor words. Possible implications of this result for how activation is transmitted within the speech production system are discussed.     

The role of perceptual and semantic elaboration in high- and low-imagery sentence recall

Sentence imagery effects in recall are predicted by both perceptual and semantic elaboration models. The former attributes superior recall of high-imagery sentences to the addition of perceptual network components to an existing semantic network; the latter claims that additions of semantic components are involved. In order to identify the responsible components, free associates were generated to otherwise similar high- and low-imagery sentences in a short-term memory task. In accordance with the perceptual elaboration model, associates differed in rated imagery, but not in number. In a second study, the causal role of perceptual elaboration in recall was investigated by using high- and low-imagery sentence associates as recall cues. Differential effects of cue imagery were found for high-imagery sentences, indicating that perceptual codes are in part responsible for superior high-imagery sentence recall. Evidence is presented that perceptual and semantic network components are involved in a processing trade-off, and the adequacy of present network models to explain it is discussed.     

Investigating semantic memory impairments: The contribution of semantic priming

Abstract

The semantic priming task is a valuable tool in the investigation of semantic memory impairments in patients with acquired disorders of language. This is because priming performance reflects automatic or implicit access to semantic information, unlike most other tests of semantic knowledge, which rely on explicit, voluntary access. Priming results are important for two main reasons: First, normal priming results may be observed in patients who perform poorly on other semantic memory tests, enabling us to distinguish between loss of, or damage to, information in semantic memory, and voluntary access to that information. Second, we can investigate the detailed pattern of loss and preservation of different types of semantic information, by charting the priming effects for different kinds of words, and different kinds of semantic relations between primes and targets.

We discuss the use of the priming task in this context, and address some of the theoretical and methodological criticisms that have been raised in connection with use of the priming task to address these issues. We then describe two recent studies in which we have employed semantic priming tasks, along with other more traditional methods, to investigate specific questions about the semantic memory deficits of three patients.     

Serial and free recall in children can be improved by training: evidence for the importance of phonological and semantic representations in immediate memory tasks

Children were assigned to three groups given training on unfamiliar words--phoneme-awareness training, rhyme training, and vocabulary training--and an untrained control group. Before and after training, we assessed the children's performance on serial- and free-recall tasks with these words, as well as their ability to define the words, manipulate phonemes in them, and generate rhymes for them. We found that phoneme-awareness training improved serial recall substantially and improved free recall to a lesser extent. In contrast, vocabulary training produced a substantial increase in free recall and a lesser increase in serial recall. These effects on recall were specific and did not generalize to untrained words. Rhyme training produced increases in rhyming skills but no increase in either serial or free recall. We argue that serial and free recall depend on common memory mechanisms, but serial recall relies more on phonological codes and free recall relies more on semantic codes.     

Two modality effects in verbal short-term memory: Evidence from sentence recall

This paper investigates the mechanisms underlying the standard modality effect (i.e., better recall performance for auditorily presented than for visually presented materials), and the modality congruency effect (i.e., better memory performance if the mode of recall and presentation are congruent rather than incongruent). We tested the assumption that the standard modality effect is restricted to the most recent word(s) of the sentences but occurs in both verbatim and gist recall (Experiments 1 and 2), whereas the modality congruency effect should be evident for the rest of the sentence when using verbatim recall (Experiment 3) but not when using gist recall (Experiment 4). All experiments used the Potter-Lombardi intrusion paradigm. When the target word was the most recent word of the sentence, a standard modality effect was found with both verbatim recall and gist recall. When the target word was included in the middle of the sentences, a modality congruency effect was found with verbatim recall but not with gist recall.     

Interactive effects of noise and neuroticism on recall from semantic memory

Subjects recalled names of countries during 8 or 5 min. (Experiments 1 and 2) or performed a set of brief (40 sec) tasks recalling items from semantic or factual memory (Experiment 3), either in silence or in intermittent white noise (95 dB (A)). Noise interfered consistently with the performance of "neurotic" subjects (i.e., subjects scoring above the median on the EPI scale of neuroticism) but had little effect on that of "stable" ones. Performance was not significantly related to extraversion, nor to self-rated activation, and it was uncorrelated with neuroticism in the no-noise condition. An interpretation of the results emphasizing the distracting effects of noise is discussed.     

Retention functions for syntactic and lexical vs semantic information in sentence recognition memory

In a continuous recognition memory design, Ss judged whether each sentence was identical in form and meaning to some previously presented sentence, then judged whether the sentence was identical in meaning irrespective of form, and, finally, rated the likelihood of recognizing the sentence ff it was presented an hour later (memorability). The Ss were given sentences that were new, identical to, or paraphrased from some previously presented sentence, at delays ranging from 0 sec to 2 h. Long-term memory for both semantic information and syntactic-lexical information decayed according to the same exponential-power retention function previously found to be characteristic of the decay of simpler verbal materials (nonsense items, letters, digits, words, and word pairs). Semantic memory primarily differed from syntactic-lexical memory in that the semantic information had a far higher degree of learning, but the decay rate for syntactic-lexical information was also approximately 5 0% greater than the decay rate for semantic information.     

Accessing short-term memory with semantic and phonological information: A time-course analysis

The time course for accessing short-term memory representations on the basis of item, phonological, and semantic information was measured with a speed-accuracy tradeoff (SAT) variant of a recognition probe task. Subjects studied 5-word lists and then judged whether a test word (1) was in the study list (item judgment); (2) rhymed with a word in the study list (rhyme judgment); or (3) was a synonym of a word in the study list (synonym judgment). Analysis of the SAT retrieval functions demonstrated that judgments based on phonological and semantic information were slower and less accurate than judgments based on composite item representations. The slower retrieval dynamics for rhyme and synonym judgments suggest that judgments based on component properties of the memory trace are mediated by either a generate or recall process distinct from the parallel or direct-access mechanism used in item judgments.     

A semantic memory sentence verification model based on relative judgment theory

A subjective referent model of sentence verification in semantic memory tasks based on the relative judgment theory of Link and Heath (1975), together with the derivation of a discriminability index, are presented in this paper. An attractive feature of the model is its consideration of both error rates and response times (RTs) in the calculation of the discriminability index. The model is also able to account for the frequent finding in semantic memory tasks that error RTs are longer than correct RTs. A partial replication of Experiment 2 of McCloskey and Glucksberg's (1979) sentence verification context effect studies, in which we employed 44 subjects and 28 categories, and controlled for item familiarity, revealed that error RTs were consistently longer than correct RTs--a finding inconsistent with the McCloskey and Glucksberg property comparison model, but in accord with the subjective referent model. An important fortuitous result was the detection of a context effect by the discriminability measure, an effect not detected by the RT data alone. The discriminability measures yielded a near perfect correlation with estimates of the mean step size of the random walk obtained by application of the parameter estimation program FITTRW (Heath, 1983).     

Investigating the predictive roles of working memory and IQ in academic attainment

There is growing evidence for the relationship between working memory and academic attainment. The aim of the current study was to investigate whether working memory is simply a proxy for IQ or whether there is a unique contribution to learning outcomes. The findings indicate that children’s working memory skills at 5 years of age were the best predictor of literacy and numeracy 6 years later. IQ, in contrast, accounted for a smaller portion of unique variance to these learning outcomes. The results demonstrate that working memory is not a proxy for IQ but rather represents a dissociable cognitive skill with unique links to academic attainment. Critically, we find that working memory at the start of formal education is a more powerful predictor of subsequent academic success than IQ. This result has important implications for education, particularly with respect to intervention.     

Reexamining the phonological similarity effect in immediate serial recall: The roles of type of similarity,category cuing,and item recall

Study of the phonological similarity effect (PSE) in immediate serial recall (ISR) has produced a conflicting body of results. Five experiments tested various theoretical ideas that together may help integrate these results. Experiments 1 and 2 tested alternative accounts that explain the effect of phonological similarity on item recall in terms of feature overlap, linguistic structure, or serial order. In each experiment, the participants' ISR was assessed for rhyming, alliterative, and similar nonrhyming/nonalliterative lists. The results were consistent with the predictions of the serial order account, with item recall being higher for rhyming than for alliterative lists and higher for alliterative than for similar nonrhyming/nonalliterative lists. Experiments 3 and 4 showed that these item recall differences are reduced when list items repeat across lists. Experiment 5 employed rhyming and dissimilar one-syllable and two-syllable lists to demonstrate that recall for similar (rhyming) lists can be better than that for dissimilar lists even in a typical ISR task in which words are used, providing a direct reversal of the classic PSE. These and other previously published results are interpreted and integrated within a proposed theoretical framework that offers an account of the PSE.     

Separate roles for executive and phonological components of working memory in mental arithmetic

A dual-task methodology was used to investigate the roles played by executive and phonological aspects of working memory in mental arithmetic. Experiment 1 showed that suppression of articulation impaired the ability to add a pair of briefly presented three-digit numbers. Suppression had no effect when the need to store temporarily was minimized by making the numbers visible throughout calculation. Experiment 2 showed that disrupting executive processes by requiring concurrent performance of a Trails task impaired the ability to add numbers that remained permanently visible. Performance on the Trails task deteriorated as the number of carry operations in the addition increased. Experiment 3 showed that this decline in Trails performance was not simply due to the extra time taken by carrying. These and other features of the results suggest that the carrying component of mental arithmetic places substantial demands on executive processes, whereas the need to retain problem information is met by the phonological loop. The results are consistent with an interpretation of executive processes according to which there is a limit on the capacity to inhibit strongly primed routine operations.     

The fate of originally presented surface information following recall errors in sentence memory tasks

Pictures are remembered better than their names. This picture superiority effect in episodic memory has been attributed either to the greater sensory distinctiveness of pictures or to their greater conceptual distinctiveness. Weldon and Coyote (1996) tested the conceptual distinctiveness hypothesis by comparing how well pictures as opposed to words primed in two conceptual implicit memory tasks (category production and word association). They found no picture superiority in priming and concluded that the basis of the picture superiority effect must then be pictures' greater sensory distinctiveness. Using the same logic, we compared how well pictures as opposed to words primed in a perceptual implicit memory task (picture and word fragment identification). The sensory distinctiveness theory would predict that pictures should prime picture fragment identification better than words prime word fragment identification, a result we call the picture superiority in within-form priming. Across three experiments which manipulated the encoding task at study, only one showed picture superiority in within-form priming. In contrast, in all three experiments there was robust picture superiority in recall, and exposure to pictures and words at study and test produced independent effects in which both study and test exposure to pictures was more effective for recall than exposure to words. We consider how these results might be reconciled by differences in retrieval demands between recall and fragment identification.     

Opposing effects of phonological similarity on item and order memory of words and nonwords in the serial recall task

This study shows that the classical phonological similarity effect (PSE) in immediate serial recall is critically affected by the lexicality of list items, the type of phonological similarity involved, and the scoring procedure. PSE was present in the serial recall score when phonologically distinct words were compared to words that share the middle vowel and end consonant (rhyming lists). PSE was absent in the serial recall score when phonologically distinct words were compared to words that share the initial and final consonants (consonant frame lists). There was a reversal of PSE in serial recall of nonwords when comparing distinct lists to both types of similar lists. Recall accuracy on the other hand was higher for distinct lists regardless of lexicality. Item errors dominated in relation to order errors in the case of nonwords, whereas order errors dominated in relation to item errors in the case of words. Furthermore, order errors were more common for phonologically similar lists, whereas item errors were more common for phonologically distinct lists. This may be the result of intra‐list and inter‐list interference, respectively. The dominance of the former error type may cause a classical PSE, whereas the dominance of the latter error type may cause a reversal of PSE. Finally, an item identification task yielded no evidence of an association between intra‐list interference and discriminability of items in a list.     

The roles of sequencing and verbal working memory in sentence comprehension deficits in Parkinson's disease

Studies of sentence comprehension deficits in Parkinson's disease (PD) patients suggest that language processing involves circuits connecting subcortical and cortical regions. Anatomically segregated neural circuits appear to support different cognitive and motor functions. To investigate which functions are implicated in PD comprehension deficits, we tested comprehension, verbal working memory span, and cognitive set-switching in a non-linguistic task in 41 PD patients; we also obtained speech measurements reflecting motor sequencing processes that may be involved in articulatory rehearsal within working memory. Comprehension of sentences with center-embedded or final relative clauses was impaired when they could not be understood from lexical semantic content alone. Overall comprehension error rates correlated strongly with impaired set-switching and significantly with reduced working memory span and speech motor sequencing deficits. Correlations with comprehension of different sentence structures indicate that these impairments do not represent a single deficit; rather, PD comprehension deficits appear to arise from several independent mechanisms. Deficits in cognitive set-switching or underlying inhibitory processes may compromise the ability to process relative clauses. Deficits in verbal working memory appear to impair comprehension of long-distance dependencies. Speech sequencing correlated with neither set-switching nor verbal working memory span, consistent with their being supported by independent, segregated cortico-subcortical circuits.     

Phonological information in immediate and delayed sentence recall

Potter and Lombardi (1990) state in their conceptual regeneration hypothesis that immediate sentence recall is only based on conceptual and lexical information; phonological information does not contribute. As experimental evidence for this hypothesis, they reported that if a sentence is followed by a word list that included a lure word similar to one of the content words of the sentence (target word), the lure word frequently intrudes into sentence recall. We demonstrated that Potter and Lombardi did not observe any influence of phonological information because list presentation followed sentence presentation, and phonological information was discarded. We observed that phonological information influenced the intrusion rate if recall was not delayed by the subsequent presentation of a word list. With immediate recall, the lure intrusion effect disappeared in auditorily presented sentences. This shows that, if available, phonological information contributes to sentence recall.