Functional characteristics of auditory temporal—spatial short-term memory: Evidence from serial order errors.

The functional characteristics of auditory temporal-spatial short-term memory were explored in 8 experiments in which the to-be-remembered stimuli were sequences of bursts of white noise presented in spatial locations separated in azimuth. Primacy and recency effects were observed in all experiments. A 10-s delay impaired recall for primacy and middle list items but not recency. This effect was shown not to depend on the response modality or on the incidence of omissions or repetitions. Verbal and nonverbal secondary tasks did not affect memory for auditory spatial sounds. Temporal errors rather than spatial errors predominated, suggesting that participants were engaged in a process of maintaining order. This pattern of results may reflect characteristics that serial recall has in common with verbal and spatial recall, but some are unique to the representation of memory for temporal-spatial auditory events. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evolution on a volcanic conveyor belt: using phylogeographic reconstructions and K-Ar-based ages of the Hawaiian Islands to estimate molecular evolutionary rates

This article reports dissociations between verbal span and the recency portion of the serial position curve in immediate free recall, in 2 neuropsychological case studies and in 3 experiments with normal participants. Patient A. N. presented with an impaired serial verbal span while showing an intact recency effect. The opposite pattern was observed in patient G. C., who despite a poor recency showed normal span in verbal serial recall tasks. Experiments 1 and 2 showed a recency effect with visually and auditory presented lists and written recall was resistant to the effects of articulatory suppression and of irrelevant speech, but was disrupted by the suffix effect. Experiment 3 showed that in contrast with recency, memory span was affected by articulatory suppression and irrelevant speech during presentation but not by a suffix. These findings are not consistent with the idea that span and recency measure aspects of the same memory system. Moreover, in clinical practice, they should not be used as equivalent alternatives.     

Dissociation between recency and span: Neuropsychological and experimental evidence.

This article reports dissociations between verbal span and the recency portion of the serial position curve in immediate free recall, in 2 neuropsychological case studies and in 3 experiments with normal participants. Patient A. N. presented with an impaired serial verbal span while showing an intact recency effect. The opposite pattern was observed in patient G. C., who despite a poor recency showed normal span in verbal serial recall tasks. Experiments 1 and 2 showed a recency effect with visually and auditory presented lists and written recall was resistant to the effects of articulatory suppression and of irrelevant speech, but was disrupted by the suffix effect. Experiment 3 showed that in contrast with recency, memory span was affected by articulatory suppression and irrelevant speech during presentation but not by a suffix. These findings are not consistent with the idea that span and recency measure aspects of the same memory system. Moreover, in clinical practice, they should not be used as equivalent alternatives. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sources of recency effects in free recall.

Discusses evidence casting doubt on the primary-memory account of the recency effect in recall and reviews an alternate account that attributes recency to the use of temporal or contextual cues. The discussion is presented in the paradigm of free recall. The recency effect refers to the fact that when people memorize a list of words, they tend to recall items at the end of the list more often than those in the middle. Recency effects have often been attributed to output from primary memory, a short-term memory buffer system. Evidence that recency effects can be found in the absence of primary memory (in conditions of concurrent distraction, multicategory lists, interactions of other independent variables with serial position, negative recency effects, and auditory recency) is reviewed. It is concluded that primary-memory theories are no longer adequate accounts for the recency effect. A temporal-contextual theory of the recency effect is discussed as a plausible alternative account, although these accounts are not fully developed or tested. (108 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effect of presentation rate on serial memory in young children with specific language impairment

The study examined the serial memory ability of a group of preschool children with specific language impairment (SLI) who were compared to age and language control groups. The children were asked to recognize serial patterns under short and long presentation durations. The subjects were presented with images of common objects (that appeared to be easily recoded into a phonological form) and iconic images of scribble drawings and unfamiliar faces (that did not appear to invite recoding). Under long presentation conditions, the performance of children with SLI resembled that of their age-matched peers on all 3 types of tasks. However, under short presentation conditions, children with SLI performed worse than their age-matched peers on all 3 tasks (and similarly to their language-matched peers). The performance of the children with SLI declined dramatically in all conditions when the items were presented for a brief period. If the serial memory deficits of young children with SLI were specific to phonological processing, their performance on recognizing the pattern of common objects should have been impaired, but not their performance with other visual tasks that are less likely to be recoded. Instead, serial memory in children with SLI was affected by presentation duration across tasks. The findings suggest that recognizing serial patterns is dependent, in part, on the speed of processing serial information. The findings are discussed in relation to models of limited capacity processing.     

Semantic cuing and the scale insensitivity of recency and contiguity.

In recalling a set of previously experienced events, people exhibit striking effects of recency, contiguity, and similarity: Recent items tend to be recalled best and first, and items that were studied in neighboring positions or that are similar to one another in some other way tend to evoke one another during recall. Effects of recency and contiguity have most often been investigated in tasks that require people to recall random word lists. Similarity effects have most often been studied in tasks that require people to recall categorized word lists. Here we examine recency and contiguity effects in lists composed of items drawn from 3 distinct taxonomic categories and in which items from a given category are temporally separated from one another by items from other categories, all of which are tested for recall. We find evidence for long-term recency and for long-range contiguity, bolstering support for temporally sensitive models of memory and highlighting the importance of understanding the interaction between temporal and semantic information during memory search. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Recency and suffix effects in serial recall of musical stimuli.

Previous research indicates that auditory presentation of verbal items leads to larger recency effects in recall than visual presentation. This enhanced recency can be eliminated if a stimulus suffix (an irrelevant sound) follows the last item. Four experiments, with 126 university students as Ss, tested the hypothesis that recency and suffix effects in serial recall result from a speech-specific process. It was demonstrated that serial recall of musical notes played on a piano exhibited substantial recency effects. These recency effects were reduced when the list items were followed by either a piano chord or the word start. However, a white-noise suffix had no effect on recency. It is concluded that this pattern of data is consistent with current work on auditory perception and places constraints on theories of recency and suffix effects. (55 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Short-term memory processes in children with reading and arithmetic learning disabilities.

Examined the role of phonemic coding in short-term memory in 45 children with a reading disability, 38 children with a specific arithmetic disability, and 89 normal children, as measured by the Wide Range Achievement Test. Ss, aged 7–13 yrs, were administered a series of tasks that involved the visual or auditory presentation of rhyming and nonrhyming letters and either an oral or a written response. Younger Ss (7–8 yrs) with a reading disability did not show any difference between the recall of nonrhyming and rhyming letters, whereas normal Ss of the same age did. Older reading-disabled Ss (aged 9–23 yrs), like their normal counterparts, had significantly poorer recall of rhyming as opposed to nonrhyming letters. However, their overall levels of performance were significantly lower than normals. The same pattern was found with Ss with arithmetic disabilities for the visual presentation of stimuli. For the auditory presentation of stimuli, the performance of Ss with arithmetic disabilities resembled that of normals, except at the youngest ages. Whereas a deficiency in phonological coding may characterize younger children with learning disabilities, older children with learning disabilities appear to use a phonemic code but have a more general deficit in short-term memory. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Auditory lexical decisions of children with specific language impairment

To determine whether children with specific language impairment (SLI) take longer than age peers to recognize sequences of sounds that represent words in their lexicon, we compared auditory lexical decision times of children with SLI to those of typically developing age peers. Children with SLI were significantly slower than peers, but speed of word recognition was not correlated with measures of language comprehension for children with SLI. Furthermore, time to detect an auditory signal and initiate a vocal response did not account for the differences between groups. Possible interpretations of the results are discussed with two explanations-differences between groups in task-related factors that stressed processing capacity or in the nature of phonetic/phonological representations-seeming more likely than others.     

Serial recall versus recall by categories in short-term memory.

C. G. Penney (1980) reported that serial recall of a list containing both auditorily and visually presented verbal items produced a lower level of recall than did separate recall of auditory and visual items. This finding was interpreted as support for the hypothesis that auditory and visual items are processed in separate streams in short-term memory, and that it is difficult to integrate these 2 streams into 1 sequence for rehearsal. The present study tested an alternate interpretation of the earlier results, the hypothesis that retention of order information is facilitated by S's being able to organize the list into 2 short sequences rather than 1 long sequence. Three experiments (72 university students) were carried out in which spatial location or category of stimulus material (letters or digits) was used to establish 2 types of items. Total recall from a list did not differ significantly between the serial and category recall conditions. Results rule out the organizational interpretation of the bisensory experiment and, therefore, provide indirect support for the separate streams hypothesis. (French abstract) (6 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memorial and strategic determinants of tactile recency.

Across 4 experiments, recency arising from the presentation of 5-item tactile lists was assessed with immediate and delayed recall with or without a same-modality suffix. The lists were presented with or without concurrent verbalization and at rates varying from 0.5 s to 2 s per item. Delaying recall or the addition of a suffix impaired recency both in the absence of concurrent verbalization during list presentation and at the 1-s presentation rate. In contrast, both concurrent verbalization during list presentation and a 0.5-s presentation rate restored recency for both the delayed recall and suffix conditions. This pattern of data is problematic for sensory memory and for trace discriminability accounts of modality and suffix effects. It is suggested that a sensory memory account together with an attention-biasing strategy by which limited encoding resources are diverted toward the terminal list item can better accommodate the data. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Progression of renal failure after subtotal nephrectomy in transgenic rats carrying an additional renin gene [TGR(mREN2)27]

Monkey auditory memory was tested with increasing list lengths of 4, 6, 8, and 10 sounds. Five-hundred and twenty environmental sounds of 3-s duration were used. In Experiment 1, the monkeys initiated each list by touching the center speaker. They touched 1 of 2 side speakers to indicate whether a single test sound (presented from both side speakers simultaneously) was or was not in the list. The serial-position functions showed prominent primacy effects (good first-item memory) and recency effects (good last-item memory). Experiment 2 repeated the procedure without the list-initiation response and with a variable intertrial interval. The results of both experiments were similar and are discussed in relation to theories and hypotheses of serial-position effects.     

Examining the relationship between free recall and immediate serial recall: The effects of list length and output order.

In 4 experiments, participants were presented with lists of between 1 and 15 words for tests of immediate memory. For all tasks, participants tended to initiate recall with the first word on the list for short lists. As the list length was increased, so there was a decreased tendency to start with the first list item; and, when free to do so, participants showed an increased tendency to start with one of the last 4 list items. In all tasks, the start position strongly influenced the shape of the resultant serial position curves: When recall started at Serial Position 1, elevated recall of early list items was observed; when recall started toward the end of the list, there were extended recency effects. These results occurred under immediate free recall (IFR) and different variants of immediate serial recall (ISR) and reconstruction of order (RoO) tasks. We argue that these findings have implications for the relationship between IFR and ISR and between rehearsal and recall. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Risk factors and prevention of vascular complications in polycythemia vera

Two experiments investigated long-term verbal memory performance in groups of 20-year-old heavy (HSDs) and light social drinkers (LSDs), in the presence and absence of a pharmacological challenge (lorazepam 2 mg). In Experiment 1 (n = 13), a verbal learning task was presented visually and it was found that lorazepam significantly impaired delayed verbal recall performance in both groups. Experiment 2 (n = 14) assessed the effect of presenting the verbal learning task in the auditory compared to the visual modality. Both groups' performance on the delayed trials of the visually presented task was reduced in the lorazepam treatment. However, in the auditory presented task, lorazepam reduced 30-min delayed recall performance in the HSDs but not in the LSDs. The differential effect of lorazepam on HSDs compared to LSDs on delayed recall performance when material is presented in the auditory modality may suggest that frequent heavy social drinking results in changes in CNS functioning.     

Multiple resources in divided attention: A cross-modal test of the independence of hemispheric resources.

Used a dual-task methodology to assess a multiple-resources account of information processing in which each cerebral hemisphere is assumed to have access to its own finite amount of attentional resources. A visually presented verbal memory task was paired with an auditory tone memory task, and Ss, 19 right-handed male undergraduates, were paid to emphasize one task more than the other. When Ss were trying to remember tones presented to the right ear, they could trade performance between tasks as a function of the emphasis condition, whereas on left-ear trials they could not. A control session indicated that stimuli presented to the unattended ear demanded processing resources, even when it was to the detriment of performance. Data support the 2nd author and M. C. Polson's (see record 1982-07236-001) model of independence between the hemispheres' resource supplies. (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Pop-out into memory: A retrieval mechanism that is enhanced with the recall of subject-performed tasks.

Subject-performed tasks (SPTs; i.e., carrying out the actions during study) improve free recall of action phrases without enhancing relational information. By this mechanism, items pop into a person's mind without active search, and this process especially extends the recency effect. The authors demonstrated the existence of the extended recency effect and its importance for the SPT recall advantage (Experiments 1 and 2). Carrying out the action and not semantic processing caused the effect (Experiment 3). The extended recency effect was also not a consequence of a deliberate last-in, first-out strategy (Experiment 4), and performing a difficult secondary task (an arithmetic task) during recall reduced memory performances but did not influence the extended recency effect (Experiment 5). These data support the theory that performing actions during study enhances the efficiency of an automatic pop-out mechanism in free recall. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for a grammar-specific deficit in children

BACKGROUND: Specific language impairment (SLI) is a disorder in which language acquisition is impaired in an otherwise normally developing child. SLI affects around 7% of children. The existence of a purely grammatical form of SLI has become extremely controversial because it points to the existence and innateness of a putative grammatical subsystem in the brain. Some researchers dispute the existence of a purely grammatical form of SLI. They hypothesise that SLI in children is caused by deficits in auditory and/or general cognitive processing, or social factors. There are also claims that the cognitive abilities of people with SLI have not yet been sufficiently characterised to substantiate the existence of SLI in a pure grammatical form. RESULTS: We present a case study of a boy, known as AZ, with SLI. To investigate the claim for a primary grammatical impairment, we distinguish between grammatical abilities, non-grammatical language abilities and non-verbal cognitive abilities. We investigated AZ's abilities in each of these areas. AZ performed normally on auditory and cognitive tasks, yet exhibited severe grammatical impairments. This is evidence for a developmental grammatical deficit that cannot be explained as a by-product of retardation or auditory difficulties. CONCLUSIONS: The case of AZ provides evidence supporting the existence of a genetically determined, specialised mechanism that is necessary for the normal development of human language.     

Memory of auditory lists by rhesus monkeys (Macaca mulatta).

Monkey auditory memory was tested with increasing list lengths of 4, 6, 8, and 10 sounds. Five-hundred and twenty environmental sounds of 3-s duration were used. In Experiment 1, the monkeys initiated each list by touching the center speaker. They touched 1 of 2 side speakers to indicate whether a single test sound (presented from both side speakers simultaneously) was or was not in the list. The serial-position functions showed prominent primacy effects (good first-item memory) and recency effects (good last-item memory). Experiment 2 repeated the procedure without the list-initiation response and with a variable intertrial interval. The results of both experiments were similar and are discussed in relation to theories and hypotheses of serial-position effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A temporal distinctiveness theory of recency and modality effects.

Conducted 4 experiments with 40 undergraduates and 60 Ss drawn from a university community to confirm the qualitative and quantitative predictions of a temporal distinctiveness theory of contextually cued retrieval from memory as applied to recency and modality (auditory vs visual) effects on the recall of a list of word pairs. Results of Exp I demonstrated that increasing the length of the temporal isolation of the last word pair aurally presented increased recall of the item; increase in recall of the last item was smaller or absent for the visual presentation of the pairs. Exp II indicated that as the number of word pairs isolated at the end of the list increased, the size of the modality effect decreased. Temporal distinctiveness between the 1st and 2nd pairs in Exp III revealed auditory superiority in recall of the 1st pair, an effect that was eliminated in Exp IV when isolated interval occurred between the 3rd and 4th presentation of a 6-item word pair list. A mathematical model of the quantitative predictions of the theory is appended. (46 ref) (PsycINFO Database Record (c) 2011 APA, all rights reserved)