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Psychological Bulletin Sep 2017A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive... (Review)
Review
A commonly expressed view is that short-term memory (STM) is nothing more than activated long-term memory. If true, this would overturn a central tenet of cognitive psychology-the idea that there are functionally and neurobiologically distinct short- and long-term stores. Here I present an updated case for a separation between short- and long-term stores, focusing on the computational demands placed on any STM system. STM must support memory for previously unencountered information, the storage of multiple tokens of the same type, and variable binding. None of these can be achieved simply by activating long-term memory. For example, even a simple sequence of digits such as "1, 3, 1" where there are 2 tokens of the digit "1" cannot be stored in the correct order simply by activating the representations of the digits "1" and "3" in LTM. I also review recent neuroimaging data that has been presented as evidence that STM is activated LTM and show that these data are exactly what one would expect to see based on a conventional 2-store view. (PsycINFO Database Record
Topics: Brain; Humans; Memory, Long-Term; Memory, Short-Term; Psychological Theory
PubMed: 28530428
DOI: 10.1037/bul0000108 -
Annual Review of Psychology 2008The past 10 years have brought near-revolutionary changes in psychological theories about short-term memory, with similarly great advances in the neurosciences. Here, we... (Review)
Review
The past 10 years have brought near-revolutionary changes in psychological theories about short-term memory, with similarly great advances in the neurosciences. Here, we critically examine the major psychological theories (the "mind") of short-term memory and how they relate to evidence about underlying brain mechanisms. We focus on three features that must be addressed by any satisfactory theory of short-term memory. First, we examine the evidence for the architecture of short-term memory, with special attention to questions of capacity and how--or whether--short-term memory can be separated from long-term memory. Second, we ask how the components of that architecture enact processes of encoding, maintenance, and retrieval. Third, we describe the debate over the reason about forgetting from short-term memory, whether interference or decay is the cause. We close with a conceptual model tracing the representation of a single item through a short-term memory task, describing the biological mechanisms that might support psychological processes on a moment-by-moment basis as an item is encoded, maintained over a delay with some forgetting, and ultimately retrieved.
Topics: Attention; Brain; Cognition; Humans; Memory, Short-Term; Neural Pathways; Psychological Theory; Psychophysiology; Retention, Psychology; Time Factors
PubMed: 17854286
DOI: 10.1146/annurev.psych.59.103006.093615 -
Annual Review of Psychology Jan 2015For more than 50 years, psychologists and neuroscientists have recognized the importance of a working memory to coordinate processing when multiple goals are active and... (Review)
Review
For more than 50 years, psychologists and neuroscientists have recognized the importance of a working memory to coordinate processing when multiple goals are active and to guide behavior with information that is not present in the immediate environment. In recent years, psychological theory and cognitive neuroscience data have converged on the idea that information is encoded into working memory by allocating attention to internal representations, whether semantic long-term memory (e.g., letters, digits, words), sensory, or motoric. Thus, information-based multivariate analyses of human functional MRI data typically find evidence for the temporary representation of stimuli in regions that also process this information in nonworking memory contexts. The prefrontal cortex (PFC), on the other hand, exerts control over behavior by biasing the salience of mnemonic representations and adjudicating among competing, context-dependent rules. The "control of the controller" emerges from a complex interplay between PFC and striatal circuits and ascending dopaminergic neuromodulatory signals.
Topics: Brain; Functional Neuroimaging; Humans; Memory, Short-Term
PubMed: 25251486
DOI: 10.1146/annurev-psych-010814-015031 -
Journal of Visualized Experiments : JoVE Aug 2017The object recognition test (ORT) is a commonly used behavioral assay for the investigation of various aspects of learning and memory in mice. The ORT is fairly simple...
The object recognition test (ORT) is a commonly used behavioral assay for the investigation of various aspects of learning and memory in mice. The ORT is fairly simple and can be completed over 3 days: habituation day, training day, and testing day. During training, the mouse is allowed to explore 2 identical objects. On test day, one of the training objects is replaced with a novel object. Because mice have an innate preference for novelty, if the mouse recognizes the familiar object, it will spend most of its time at the novel object. Due to this innate preference, there is no need for positive or negative reinforcement or long training schedules. Additionally, the ORT can also be modified for numerous applications. The retention interval can be shortened to examine short-term memory, or lengthened to probe long-term memory. Pharmacological intervention can be used at various times prior to training, after training, or prior to recall to investigate different phases of learning (i.e., acquisition, early or late consolidation, or recall). Overall, the ORT is a relatively low-stress, efficient test for memory in mice, and is appropriate for the detection of neuropsychological changes following pharmacological, biological, or genetic manipulations.
Topics: Animals; Humans; Learning; Male; Memory, Short-Term; Mice; Mice, Transgenic; Recognition, Psychology; Visual Perception
PubMed: 28892027
DOI: 10.3791/55718 -
PloS One 2021Amoeboid cells constantly change shape and extend protrusions. The direction of movement is not random, but is correlated with the direction of movement in the preceding...
Amoeboid cells constantly change shape and extend protrusions. The direction of movement is not random, but is correlated with the direction of movement in the preceding minutes. The basis of this correlation is an underlying memory of direction. The presence of memory in movement is known for many decades, but its molecular mechanism is still largely unknown. This study reports in detail on the information content of directional memory, the kinetics of learning and forgetting this information, and the molecular basis for memory using Dictyostelium mutants. Two types of memory were characterized. A short-term memory stores for ~20 seconds the position of the last pseudopod using a local modification of the branched F-actin inducer SCAR/WAVE, which enhances one new pseudopod to be formed at the position of the previous pseudopod. A long term memory stores for ~2 minutes the activity of the last ~10 pseudopods using a cGMP-binding protein that induces myosin filaments in the rear of the cell; this inhibits pseudopods in the rear and thereby enhances pseudopods in the global front. Similar types of memory were identified in human neutrophils and mesenchymal stem cells, the protist Dictyostelium and the fungus B.d. chytrid. The synergy of short- and long-term memory explains their role in persistent movement for enhanced cell dispersal, food seeking and chemotaxis.
Topics: Cell Movement; Cell Polarity; Dictyostelium; Memory, Long-Term; Memory, Short-Term; Mutation; Pseudopodia
PubMed: 33571271
DOI: 10.1371/journal.pone.0246345 -
Cognition Mar 2021Short-term verbal memory is improved when words can be chunked into larger units. Miller (1956) suggested that the capacity of verbal short-term memory is determined by... (Review)
Review
Short-term verbal memory is improved when words can be chunked into larger units. Miller (1956) suggested that the capacity of verbal short-term memory is determined by the number of chunks that can be stored in memory, rather than by the number of items or the amount of information. But how does the improvement due to chunking come about, and is memory really determined by the number of chunks? One possibility is that chunking is a form of data compression. It allows more information to be stored in the available capacity. An alternative is that chunking operates primarily by redintegration. Chunks exist only in long-term memory, and enable the corresponding items in short-term memory to be reconstructed more reliably from a degraded trace. We review the data favoring each of these views and discuss the implications of treating chunking as data compression. Contrary to Miller, we suggest that memory capacity is primarily determined both by the amount of information that can be stored but also by the underlying representational vocabulary of the memory system. Given the limitations on the representations that can be stored in verbal short-term memory, chunking can sometimes allow the information capacity of short-term memory to be exploited more efficiently. (202 words).
Topics: Data Compression; Humans; Memory, Long-Term; Memory, Short-Term; Mental Recall; Vocabulary
PubMed: 33360054
DOI: 10.1016/j.cognition.2020.104534 -
Current Biology : CB Feb 2010
Review
Topics: Humans; Memory, Short-Term; Models, Neurological; Models, Psychological; Task Performance and Analysis
PubMed: 20178752
DOI: 10.1016/j.cub.2009.12.014 -
Computational Intelligence and... 2022Recently, long short-term memory (LSTM) networks are extensively utilized for text classification. Compared to feed-forward neural networks, it has feedback connections,...
Recently, long short-term memory (LSTM) networks are extensively utilized for text classification. Compared to feed-forward neural networks, it has feedback connections, and thus, it has the ability to learn long-term dependencies. However, the LSTM networks suffer from the parameter tuning problem. Generally, initial and control parameters of LSTM are selected on a trial and error basis. Therefore, in this paper, an evolving LSTM (ELSTM) network is proposed. A multiobjective genetic algorithm (MOGA) is used to optimize the architecture and weights of LSTM. The proposed model is tested on a well-known factory reports dataset. Extensive analyses are performed to evaluate the performance of the proposed ELSTM network. From the comparative analysis, it is found that the LSTM network outperforms the competitive models.
Topics: Learning; Memory, Long-Term; Memory, Short-Term; Neural Networks, Computer
PubMed: 35237308
DOI: 10.1155/2022/4725639 -
American Journal of Speech-language... Feb 2021Purpose This study was undertaken to explore whether measures of verbal short-term memory and working memory are sensitive to impairments in people with latent aphasia,...
Purpose This study was undertaken to explore whether measures of verbal short-term memory and working memory are sensitive to impairments in people with latent aphasia, who score within normal limits on typical aphasia test batteries. Method Seven individuals with latent aphasia and 24 neurotypical control participants completed 40 tasks from the Temple Assessment of Language and Short-term Memory in Aphasia (TALSA) that assess various aspects of verbal short-term memory, working memory, and language processing. Subtests were identified that differentiated between the two groups of participants. Results Twenty-one TALSA tasks were identified on which the participants with latent aphasia had significantly different performance than the typical control participants. All of these subtests engaged verbal short-term memory, and some involved working memory as well. Furthermore, the TALSA detected individual differences in linguistic profiles among participants with latent aphasia. Conclusions People with latent aphasia may be identified by tests that tap verbal short-term memory and working memory. In addition, the TALSA was found to be sensitive to the heterogeneity of this population. Further development of these measures will improve identification and treatment of this challenging population.
Topics: Aphasia; Humans; Language; Linguistics; Memory, Short-Term; Neuropsychological Tests
PubMed: 32628508
DOI: 10.1044/2020_AJSLP-19-00105 -
Neuron Apr 2023Sensory processing, short-term memory, and decision-making often deal with multiple items, or options, simultaneously. I review evidence suggesting that the brain... (Review)
Review
Sensory processing, short-term memory, and decision-making often deal with multiple items, or options, simultaneously. I review evidence suggesting that the brain handles such multiple items by "rhythmic attentional scanning (RAS)": each item is processed in a separate cycle of the theta rhythm, involving several gamma cycles, to reach an internally consistent representation in the form of a gamma-synchronized neuronal group. Within each theta cycle, items that are extended in representational space are scanned by traveling waves. Such scanning might go across small numbers of simple items linked into a chunk.
Topics: Attention; Theta Rhythm; Cerebral Cortex; Hippocampus; Memory, Short-Term
PubMed: 37023718
DOI: 10.1016/j.neuron.2023.02.015