Abstract: Immediate memory for visually presented verbal material is disrupted by concurrent speech, even when the speech is unattended and in a foreign language Unattended noise does not produce a reliable decrement These results have been interpreted in terms of a phonological short-term store that excludes non-speechlike sounds The characteristics of this exclusion process were explored by studying the effects of music on the serial recall of sequences of nine digits presented visually Experiment 1 compared the effects of unattended vocal or instrumental music with quiet and showed that both types of music disrupted STM performance, with vocal music being more disruptive than instrumental music Experiment 2 attempted to replicate this result using more highly trained subjects Vocal music caused significantly more disruption than instrumental music, which was not significantly worse than the silent control condition Experiment 3 compared instrumental music with unattended speech and with noise modulated in

Abstract: Three predictions were derived from the hypothesis that adult age differences in certain measures of cognitive functioning are attributable to age-related reductions in a processing resource such as working-memory capacity. Each prediction received at least some degree of empirical support in a study involving 120 males ranging between 20 and 79 years of age. First, older adults exhibited greater impairments of performance than did young adults when task complexity increased and more demands were placed on the limited processing resources; second, the magnitudes of these complexity effects were highly correlated across verbal (reasoning) and spatial (paper folding) tasks. Finally, statistical control of an index of a working-memory processing resource attenuated the effects of age on the measures of cognitive performance. It was concluded that further progress in understanding the mechanisms of the relation between age and cognitive functioning will require improved conceptualizations of the nature of working memory or other hypothesized mediating constructs.

Abstract: • The concentration of Δ-9-tetrahydrocannabinol in marijuana available in the United States has increased by 250% since investigations of the effects of marijuana on short-term memory first appeared in scientific journals. Moreover, previous investigations of short-term memory in long-term marijuana smokers involved adults only. We evaluated the auditory/verbal and visual/spatial memory of 10 cannabis-dependent adolescents and compared the results with performance of 17 subjects in two control groups. The control groups included 8 adolescent drug abusers who had not been long-term users of cannabis and another 9 adolescents who had never abused any drug. All three groups were matched on age, IQ, and absence of previous learning disabilities. Adolescents with a history of frequent alcohol or phencyclidine abuse were excluded from entering the study. A battery of seven neuropsychological tests was administered initially to all subjects and a parallel test battery was administered 6 weeks thereafter. Significant differences between the cannabis-dependent group and the two control groups were obtained initially on the Benton visual Retention Test (F[2,24] = 6.07) and the Wechsler Memory Scale Prose Passages (F[2,23] = 7.04). After 6 weeks of supervised abstention from intoxicants, subjects in the cannabis-dependent group showed some significant improvement on the Wechsler Memory Prose Passages score and on the Benton Visual Retention Test; however, the improvement failed to achieve statistical significance. We concluded that cannabis-dependent adolescents have selective short-term memory deficits that continue for at least 6 weeks after the last use of marijuana. (AJDC. 1989;143:1214-1219)

Abstract: Several theories assume that practice (a) results in restructuring of component processes and (b) reduces demand on working memory. Eight subjects practiced judgments about digital logic gates for over 8,000 trials. At two practice levels, subjects made judgments while retaining short-term memory loads irrelevant to the judgments, relevant but not accessed, or accessed to make the judgments. Four phenomena together provide constraints for theory: First, performance declined in moving from blocked practice to randomized practice. Second, gate and judgment type strongly affected latency. Third, these effects declined but did not disappear with practice. Fourth, the cost of accessing information in working memory remained substantial. These results are interpreted as reflecting a serial pro-cess with constant structure, while component processes become faster. The results challenge theories assuming that all learning results from restructuring or that restructuring is an automatic consequence of practice, and they support a distributed view of working memory. Several current theories of skill acquisition (e.g., Anderson, 1982, 1983, 1987; Rosenbloom & Newell, 1987) share the assumptions that (a) practice results in the reorganization or r£rtrwc/un/7# of component processes, and (b) practice reduces the load on a working memory that serves as a single workspace for carrying out cognitive processes. In the study reported here, we observed the acquisition of procedural skill for judgments about causal rules over the course of approximately 20 hr (over 8,000 trials) of practice. The results challenge the above assumptions and suggest an alternative view in which the organization of component processes and use of working memory remain constant while the speed of component processes increases (and attentional load decreases) with extended practice (see Schneider, 1985).

Abstract: The purpose of this study was to investigate the hypothesis that the manner in which a reading disability is defined will influence the conclusions that are made about the characteristics of the disability. To test this hypothesis, learning disabled and normally achieving children, aged 6 to 14, were administered tasks measuring grammatical, shortterm memory, phonological, reading, and visual-spatial skills. The poor readers were divided into groups of poor readers with 1. inadequate phonics skills, 2. inadequate word recognition skills, 3. adequate word recognition skills but low reading comprehension scores, and 4. adequate word recognition scores but a slow reading speed.

Abstract: Phonological processing abilities were studied in a patient who, following focal brain damage, showed selective impairment in non-word reading, writing, and repetition and also a severe short-term memory (STM) deficit specific for auditorily presented verbal material. The patient could execute tasks involving phonemic manipulation and awareness perfectly. Our data, in contrast with earlier observations in a case of developmental phonological dyslexia, show that acquired impairment in non-word reading, writing, repetition, and immediate memory may occur despite good phonological processing abilities. The role of STM in processing meaningless verbal material is discussed.

Abstract: Twelve students from classrooms for children with severe language disorders and 12 age-matched controls were evaluated for short-term memory scanning speed using the Sternberg task. Sets of two, th...

Abstract: Effects of stimulus movement on learning, transfer, matching, and short-term memory performance were assessed with 2 monkeys using a video-task paradigm in which the animals responded to computer-generated images by manipulating a joystick. Performance on tests of learning set, transfer index, matching to sample, and delayed matching to sample in the video-task paradigm was comparable to that obtained in previous investigations using the Wisconsin General Testing Apparatus. Additionally, learning, transfer, and matching were reliably and significantly better when the stimuli or discriminanda moved than when the stimuli were stationary. External manipulations such as stimulus movement may increase attention to the demands of a task, which in turn should increase the efficiency of learning. These findings have implications for the investigation of learning in other populations, as well as for the application of the video-task paradigm to comparative study.

Abstract: Two experiments were conducted to determine whether adult age differences in working memory should be attributed to less efficient processing, a smaller working memory storage capacity, or both. In Experiment 1, young, middle-age, and older adults solved three addition problems before giving the answers to any. Older adults added as well as young and middle-age adults but showed a more pronounced serial position curve across the three problem positions. In Experiment 2, young and older adults constructed linear orderings (e.g., ABCD) from pairwise information presented in sentences (e.g., BC). Manipulations involving processing (e.g., type of sentence) did not interact with age differences, but those involving storage capacity (e.g., ordering length) did. All main effects and interactions support the hypothesis of a smaller storage capacity but do not rule out some processing deficit in older adults.

Abstract: In this study, we investigated bases for encoding linguistic stimuli in short-term memory. Past research has provided evidence for both phonological (sound-based) and cherological (sign-based) encoding, the former typically found with hearing subjects and the latter with deaf users of sign language. In the present experiment, encoding capabilities were delineated from encoding preferences, using 58 subjects comprising six groups differing in hearing ability and linguistic experience. Phonologically related, cherologically related, and control lists were presented orally, manually, or through both modalities simultaneously. Recall performance indicated that individuals encode flexibly, the code actually used being biased by incoming stimulus characteristics. Subjects with both sign and speech experience recalled simultaneous presentations better than ones presented orally or manually alone, which reveals the occurrence of enhanced encoding as a function of linguistic experience. Total linguistic experience appeared to determine recall accuracy following different types of encoding, rather than determining the encoding basis used.

Abstract: Publisher Summary This chapter discusses short-term memory for associations The experiments described in the chapter test the recognition of associative information over retention intervals filled with the presentation and testing of other paired associates The recognition is used rather than recall because the recognition provides a less complex view of associative information than the recall A decision process occurs in recognition that may be absent in recall Signal-detection methods applied to memory allows to separate strength effects from criterion effects in recognition memory These experiments are designed to trace out the retention curve for the recognition of associative information using a continuous paired-associates paradigm The convolution–correlation model is a distributed-memory model that assumes that all information is stored in a common memory Items are represented by random vectors and the numerical value of N is one of the parameters of the model Convolution is the associative operation and correlation is the retrieval operation

Abstract: One hundred thirty-three children with school problems referred to a hospital-based multi-disciplinary clinic were screened audiologically to determine the frequency of auditory problems, and to determine whether one could predict auditory problems from clinical data. Ninety-three (69.9%) failed one or more parts of the screening procedure. Twenty-two children (7.9% of the total group) had abnormal hearing acuity, 33 (30.6%) abnormal speech discrimination in noise, and 73 (62.4%) abnormal short term auditory memory. These figures are significantly higher than those found in a representative sample of school children. Not one of 16 items from parent and teacher questionnaires and neurodevelopmental findings predicted auditory acuity or speech in noise problems; there were correlations between short term auditory memory items and parental and teacher rating of a language problem, teacher rating of reading and sequencing problem, and neurodevelopmental finding of auditory sequencing problem. In view of this inability to clinically predict auditory processing deficits, the authors suggest that a full audiological assessment, including short term memory and speech in noise testing, is warranted as part of the evaluation of children with learning difficulties.

Abstract: What role does a phonological short-term memory store (P.S.T.S.) play in the comprehension of spoken and written sentences? One way to approach this question is to characterise the sentence comprehension performance of subjects who have a P.S.T.S. whose capacity has been reduced or even eliminated by some pathological process. When patients with reduced P.S.T.S. show comprehension deficits, it is tempting to see these as a consequence of the memory problem; and a glance at the literature on such subjects shows that a variety of authors have argued that their patients' comprehension problems are secondary to the memory deficit.The problem with these accounts is simple: when the data are examined in any detail the characteristics of the sentence comprehension deficits show great variation across patients (see, e.g. Butterworth, Campbell, & Howard, 1986). The obvious possibility is that some or all of these patients have other non-mnestic problems in sentence comprehension, which happen to cooccur with their S.T.M. deficit. We would suggest that a sentence comprehension problem can only be attributed to a P.S.T.S. deficit where:

Abstract: A paired-trial operant delayed response task has been developed to assess short-term memory function in rats. Aged rats manifest delay-dependent deficits in memory performance, whereas nucleus basalis lesions induce relatively less specific learning impairments. Both classes of deficit have been significantly ameliorated by cholinergic-rich transplants implanted in the neocortex.

Abstract: The purpose of the present experiment was to investigate the demands placed on the short term memory system by synthetic speech. We compared performance in a typical auditory short term memory task as a function of whether the items were presented by a human voice or by a text-to-speech computer voice generator. Immediate serial recall of digit strings was significantly poorer when presented by synthetic speech than when presented by natural speech. The results are consistent with the idea that comprehension of synthetic speech imposes increased resource demands on the short term memory system.

Abstract: The strategies chosen by two subgroups of second-grade LD children with short-term memory problems, but with differences in naming facility, were compared to the strategies chosen by same-age and younger nondisabled children in a real-life memory situation. The LD subjects with poor naming abilities demonstrated selected strategy failures; their strategies were interpreted to reflect a compensatory approach to the task. The LD subjects with good naming abilities demonstrated more generalized strategy failures, resembling those evidenced by younger nondisabled learners. Both groups of LD subjects were more proficient in spontaneous production of memory strategies that made minimal demands on verbal coding processes than strategies that made heavy demands on verbal representation and control. The results indicate that the LD children were not inactive; however, the strategies they favored tended to be less effective than those used by same-age, normal-learning children.

Abstract: The goal of this thesis is to identify the underlying impairments in aphasic disorders of auditory comprehension and repetition. The findings are interpreted within a cognitive neuropsychological framework. Models of normal language processing are discussed in the light of this evidence. Information processing models of the lexicon attempt to specify the stages of processing necessary for auditory comprehension, as well as different routes by which words can be repeated. Twenty fluent aphasic patients were used in the study. It was found that the patients did show qualitative differences in auditory word comprehension. Five levels of impairment were identified: word-sound deafness, word-for deafness, word-meaning deafness, a central semantic disorder and a disorder specific to abstract words. It was concluded that abstract words are more sensitive to impairment than concrete words. Word imageability was investigated in more detail in a number of experiments with a word meaning deaf patient (DRB). It was shown that his impairment is one of access from the input lexicon to the semantic system. The impairment results in under-specification in the semantic system, and an extremely robust effect of imageability in DRB's ability to comprehend and repeat auditorily presented words. This effect is not item-specific. Intriguingly, the results also suggest that DRB has an anomia for words of low imageability. In a subsequent section, the patients' abilities in repetition are investigated. Two routes for repetition are identified, a sub-lexical and a lexical/semantic route. Phonologically related errors arising in the former route tend to be non-words, occur particularly on longer words, and the errors tend to be in the final position of the string. Phonological errors arising in the lexical/semantic route are real words, tend to be higher in frequency than the stimulus items, and occur particularly on shorter words. The relationship between repetition and auditory short term memory is considered by further experiments with DRB. It is argued that sub-lexical repetition utilises the auditory short term memory system. DRB's sub-lexical repetition and his immediate serial recall are enhanced by lip read information. A model of repetition and auditory short-term memory is presented. It is argued that the system requires different input and output phonological codes, suggesting separate input and output lexicons. With the specification of how lexical information supports immediate serial recall, it is argued that there is no requirement for a direct, lexical, non-semantic route in repetition.

Abstract: Subjects recalled items from short‐term memory by speaking into a speech recognizer. Two experiments examined effects of the type of feedback provided by the device during this data entry task. Three types of feedback were compared, varying in: modality, either auditory or visual; timing, either concurrent or terminal, and specificity, either verbal or nonverbal. Recognizer performance was better with concurrent feedback than with terminal feedback and better with nonverbal feedback than with verbal feedback. In terms of the efficiency of memory (the number of errors and the rate of data throughput), performance was more impaired by concurrent verbal feedback than by nonverbal feedback. Two main functional features of feedback in automatic speech recognition were identified: (1) the degree of similarity between the feedback and the phonologically‐coded information held in short‐term memory, which pointed to the dangers of spoken feedback and to a lesser extent the use of verbal visual feedback, and (2) th...

Abstract: The idea that memory is a modular system comprising of functionally separate subsystems has been current for many years. William James (1890) proposed a distinction between “primary memory” and “secondary memory”. Many years later, a number of authors (Broadbent, 1957; Brown, 1958; Melton, 1963; Norman, 1970) proposed different models, which appeared to share the distinction between a limited-capacity short-term store and a long-term store of much greater capacity. One of the most influential of these models, also termed the modal model was proposed by Atkinson and Shiffrin (1968).

Abstract: The structure and function of memory affect medical problem solving. The purpose of this 1982 study was to test the assertion that the number of diagnoses actively entertained by novice clinicians during a simulated case would not be greater than seven, the average maximum storage capacity of short-term memory. A total of 24 junior physician's assistant students took mock medical histories and gave mock physical examinations using simulated patients. Each of the eight cases investigated by each group included a primary problem with various numbers of secondary problems. Three successive time periods, called interludes, were provided in which each student had three minutes to list all the hypotheses he or she was actively considering concerning the diagnosis of the patient's problem. Each interlude was scheduled at a progressively more complete point in the student's knowledge of the case. The results supported the assertion that was tested.