A developmental study of categorical organization in short-term memory.

Studied 3rd and 4th graders and college undergraduates to investigate the development of the ability to use taxonomic, phonemic, and sense impression categories as dimensions. Results indicate that the more sophisticated the level of encoding needed to discriminate between 2 opposing classes of information, the older the child must be before he can accomplish the task. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Exploring developmental differences in visual short-term memory and working memory.

Although visuospatial short-term memory tasks have been found to engage more executive resources than do their phonological counterparts, it remains unclear whether this is due to intrinsic differences between the tasks or differences in participants’ experience with them. The authors found 11-year-olds’ performances on both visual short-term and working memory tasks to be more greatly impaired by an executive suppression task (random number generation) than were those of 8-year-olds. Similar findings with adults (e.g., Kane & Engle, 2000) suggest that the imposition of a suppression task may have overloaded the older children’s executive resources, which would otherwise be used for deploying strategies for performing the primary tasks. Conversely, the younger children, who probably never had the capacity or know-how to engage these facilitative strategies in the first place, performed more poorly in the single task condition but were less affected in the dual task condition. These findings suggest that differences in the children’s ability to deploy task-relevant strategy are likely to account for at least part of the executive resource requirements of visual memory tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Searching for metamemory–memory connections: A developmental study.

To determine the nature and strength of metamemory–memory connections, 178 children from kindergarten, 1st, 3rd, and 5th grades participated in 2 sessions. Metamemory was assessed during Session 1 by an extensive introspective interview. Memory strategies and performance were independently measured during Session 2 on 3 tasks: free sort, cognitive cuing, and alphabet search. Metamemory–memory correlations were significant when data were combined across grades. Most within-grade correlations were not significant and did not generalize across memory tasks. Amount of knowledge about strategies failed to distinguish between individuals who used vs did not use relevant knowledge; that is, irrelevant aspects of memory correlated as highly and frequently with memory in comparison with task-specific or general knowledge about strategies. Finally, contingency analyses failed to support the contention that metamemory is a necessary prerequisite for successful memory. (21 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Visual short-term memory: A methodological caveat.

Reports that estimates of decay time for nonverbal short-term visual memory varied from less than 3 sec to beyond 30 sec in a same-different matching task with 10 male right-handed undergraduates, depending on the physical similarity between target and comparison stimuli. The more dissimilar the stimuli, the higher the memory score at all delays and the slower the decline in performance over time. Findings draw attention to the obvious but commonly neglected point that generalizations concerning the duration of visual short-term memory, particularly as measured by recognition tests, should be routinely based on a psychophysical approach in which various task conditions are systematically varied along with retention interval. Incidental to the main point, results also suggest that decay functions may reflect a decline in accessibility rather than a complete loss of availability of memory traces. (French summary) (27 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A note on repeated measures in the study of short-term memory.

Keppel's (1965) objection to averaging over repeated measures is discussed. Several possibilities for minimizing proactive interference are suggested, including increasing time between tests. Consideration is given to acceptance of a constant amount of proactive interference over conditions in which other variables are studied. The advantages of using repeated measures in regard to efficiency as well as interpretation are noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Schizophrenic short-term memory: A deficit in subjective organization.

24 schizophrenic and 24 normal Ss received 3 trials on each of 2 lists of trigrams, 1 being for recognition and the other for recall. 1/2 of the Ss received special instructions for alphabetical ordering of the recall terms, while the other 1/2 was asked to do their best. Special instructions facilitated recall of normal Ss, but not of schizophrenics. Instructions had no significant effect upon the recognition scores. The effect of trials was to increase schizophrenic recall, but not recognition, while normals showed gains both in recall and recognition. It is concluded that the schizophrenic recall deficit results, in part, from an inability to subjectively organize memory store. (French summary) (28 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Problems of method in the study of short-term memory.

Considerations of design which have been problems in the study of long-term memory are discussed in the context of short-term memory research. These problems include the type of experimental design (independent versus repeated measures), the measurement of immediate retention, and the means by which the retention interval is filled. This review indicates that these methodological problems are also present in the investigation of short-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A visual short-term memory advantage for objects of expertise.

Visual short-term memory (VSTM) is limited, especially for complex objects. Its capacity, however, is greater for faces than for other objects; this advantage may stem from the holistic nature of face processing. If the holistic processing explains this advantage, object expertise--which also relies on holistic processing--should endow experts with a VSTM advantage. The authors compared VSTM for cars among car experts and car novices. Car experts, but not car novices, demonstrated a VSTM advantage similar to that for faces; this advantage was orientation specific and was correlated with an individual's level of car expertise. Control experiments ruled out accounts based solely on verbal- or long-term memory representations. These findings suggest that the processing advantages afforded by visual expertise result in domain-specific increases in VSTM capacity, perhaps by allowing experts to maximize the use of an inherently limited VSTM system. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of word co-occurance on short-term memory: Associative links in long-term memory affect short-term memory performance.

In immediate serial recall tasks, high-frequency words are recalled better than low-frequency words. This has been attributed to high-frequency words' being better represented and providing more effective support to a redintegration process at retrieval (C. Hulme et al., 1997). In studies of free recall, there is evidence that frequency of word co-occurrence, rather than word frequency per se, may explain the recall advantage enjoyed by high-frequency words (J. Deese, 1960). The authors present evidence that preexposing pairs of low-frequency words, so as to create associative links between them, has substantial beneficial effects on immediate serial recall performance. These benefits, which are not attributable to simple familiarization with the words per se, do not occur for high-frequency words. These findings indicate that associative links between items in long-term memory have important effects on short-term memory performance and suggest that the effects of word frequency in short-term memory tasks are related to differences in interitern associations in long-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Working memory, short-term memory, and speech rate as predictors of children's reading performance at different ages.

This study explored the contribution of 2 working memory (WM) systems (the phonological loop and the central executive) to reading performance in younger (9-year-old) and older (14-year-old) children. The results showed that (a) significant age-related differences in verbal and visual-spatial WM performance were maintained when articulation speed and short-term memory (the phonological system) were partialed from the analysis and (b) WM predicted age-related differences in word recognition and comprehension performance independent of the contribution of a short-term memory and articulatory rate. The results were interpreted as support for the notion that both the phonological and the executive systems are important predictors of age-related changes in reading but that these processes operate independent of each other in predicting fluent reading. Several implications of the results are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Binomial variability in short-term memory.

Experiments in short-term memory usually collect binary data, e.g., an item is either correctly recalled or not. If the probability of recall is constant for Ss and/or items under a given condition, the proportion based on n observations can be transformed to angles by the arcsin transformation and will have variance 1/n. Violations of the assumptions are discussed and different strategies for pooling are assessed by conventional analysis of variance. Illustrative experiments with distractor and probe techniques, paired-associates and serial presentation, and single-trial free recall are briefly presented. The correspondence between observed and expected results seems good; apparently considerable latitude is possible in pooling Ss or items in data analyses of experiments in short-term memory. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Binding in short-term visual memory.

The integration of complex information in working memory, and its effect on capacity, shape the limits of conscious cognition. The literature conflicts on whether short-term visual memory represents information as integrated objects. A change-detection paradigm using objects defined by color with location or shape was used to investigate binding in short-term visual memory. Results showed that features from the same dimension compete for capacity, whereas features from different dimensions can be stored in parallel. Binding between these features can occur, but focused attention is required to create and maintain the binding over time, and this integrated format is vulnerable to interference. In the proposed model, working memory capacity is limited both by the independent capacity of simple feature stores and by demands on attention networks that integrate this distributed information into complex but unified thought objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Slope analysis in short-term memory.

Presents procedures for transforming dichotomously scored data from short-term memory experiments into slope measures for evaluation by analysis of variance techniques. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Working memory, short-term memory, and general fluid intelligence: A latent-variable approach.

A study was conducted in which 133 participants performed 11 memory tasks (some thought to reflect working memory and some thought to reflect short-term memory), 2 tests of general fluid intelligence, and the Verbal and Quantitative Scholastic Aptitude Tests. Structural equation modeling suggested that short-term and working memories reflect separate but highly related constructs and that many of the tasks used in the literature as working memory tasks reflect a common construct. Working memory shows a strong connection to fluid intelligence, but short-term memory does not. A theory of working memory capacity and general fluid intelligence is proposed: The authors argue that working memory capacity and fluid intelligence reflect the ability to keep a representation active, particularly in the face of interference and distraction. The authors also discuss the relationship of this capability to controlled attention, and the functions of the prefrontal cortex. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Serial-order short-term memory predicts vocabulary development: Evidence from a longitudinal study.

Serial-order short-term memory (STM), as opposed to item STM, has been shown to be very consistently associated with lexical learning abilities in cross-sectional study designs. This study investigated longitudinal predictions between serial-order STM and vocabulary development. Tasks maximizing the temporary retention of either serial-order or item information were administered to kindergarten children aged 4 and 5. At age 4, age 5, and from age 4 to age 5, serial-order STM capacities, but not item STM capacities, were specifically associated with vocabulary development. Moreover, the increase of serial-order STM capacity from age 4 to age 5 predicted the increase of vocabulary knowledge over the same time period. These results support a theoretical position that assumes an important role for serial-order STM capacities in vocabulary acquisition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preparation for grasping an object: A developmental study.

An optoelectronic technique (SELSPOT) was used to monitor the opening and closing of the hand during reaching actions by measuring the change in the distance between thumb and index finger. Exp 1 established an adult criterion for the development. Adults started closing the hand around the target well before touch, and the timing was dependent on the size of the target. The hand started to close earlier when grasping a small rather than a large target. In addition, the degree of hand opening was also less for a small than for a large target. In Exp 2, infants who were 5–6, 9, and 13 months of age also controlled their grasping actions visually and started closing the hand around the target in anticipation of the encounter rather than as a reaction to the encounter. The strategy of the two younger age groups was different from that of adults. They started closing the hand closer to the time of contact with the target than did the 13-month-olds, who were comparable to adults in this respect. In all age groups, reaching and grasping were most commonly organized in a continuous way; the hand started to close without any interruption in the approach. The opening of the hand was adjusted to target size in the 9- and 13-month-olds but not in the 5–6 month olds. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Enhanced visual short-term memory for angry faces.

Although some views of face perception posit independent processing of face identity and expression, recent studies suggest interactive processing of these 2 domains. The authors examined expression–identity interactions in visual short-term memory (VSTM) by assessing recognition performance in a VSTM task in which face identity was relevant and expression was irrelevant. Using study arrays of between 1 and 4 faces and a 1,000-ms retention interval, the authors measured recognition accuracy for just-seen faces. Results indicated that significantly more angry face identities can be stored in VSTM than happy or neutral face identities. Furthermore, the study provides evidence to exclude accounts for this angry face benefit based on physiological arousal, opportunity to encode, face discriminability, low-level feature recognition, expression intensity, or specific face sets. Perhaps processes activated by the presence of specifically angry expressions enhance VSTM because memory for the identities of angry people has particular behavioral relevance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adult age differences in short-term memory and subsequent long-term memory for actions.

Short-term memory for actions was investigated for young adult and elderly adult Ss with the Brown-Peterson procedure at retention intervals of 0 and 15 sec. The short-term memory trials were followed by the long-term recall of the prior to-be-remembered actions. The 15-sec retention interval was filled either with no activity or with 1 of 3 different interfering activities. Verbal interference had little effect on short-term memory at either age level. Actions performed in the interval either by the Ss or by the experimenter produced significantly lower recall scores at each age level, with the decrement being more pronounced for the elderly than for the young Ss. The long-term memory results indicated that successful short-term recall enhanced later long-term recall, regardless of age level. (PsycINFO Database Record (c) 2010 APA, all rights reserved)