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This historical chapter examines the fundamental relation between memory and attention. Information that is temporarily in or near conscious awareness is in the focus of attention, so attention and memory can be viewed as two sides of the same coin. The emerging information processing field led to the model proposed in a 1988 Psychological Bulletin article by the author, upon which the book is based. The model distinguishes between two sources of short-term memory: the currently, temporarily activated elements from long-term memory and the subset of activated elements that are in the focus of attention. Presumably, although relatively unprocessed elements of long-term memory can be automatically activated, new associations between items, and between each item and its context, may be set up only in the focus of attention. Attention is controlled partly by volition (central executive processes) and partly by changes in stimulation that recruit attention.

This chapter reviews the evidence supporting the view that representations are retained and combined across eye movements and over extended time. In particular, it considers representations that are generated over three time periods: across fixations (transsaccadic memory), over multiple fixation-saccade cycles (active online scene memory), and over the longer term (long-term scene memory). It highlights recent experiments on saccadic eye movements and visual memory. It argues that a composite scene representation that includes relatively detailed (although not sensory or iconic) visual information is generated and retained in memory across eye movements and over time as a natural consequence of active, dynamic scene perception.

In computer jargon, virtual memory is the use of a specially-designated portion of long-term memory to hold information that needs to be retrieved quickly. This chapter considers that the same type of function may occur in the human mind; long-term memory representations can be marked as relevant to the current context and thereby retrieved quickly, from a “virtual short-term store” that expands the capabilities of short-term memory. Evidence for this possibility is amassed from the short-term recall literature. The notion of virtual short-term memory was conceived contemporaneously with Ericsson and Kintsch's “long-term working memory”, which consequently was not cited. A different empirical base was used, so this chapter complements Ericsson and Kintsch. The chapter provides evidence against a “monistic view” in which the only type of working memory is long-term working memory; it provides evidence that true short-term memory also exists.

There have been wide-spread disagreements about the nature of short-term memory. What distinguishes it from long-term memory? Is the information in short-term memory forgotten as a function of time (memory decay)? Is it susceptible to a limit in capacity, the number of items that can be held at once? This chapter proposes that there are two mechanisms of short-term memory: the activated portion of long-term memory, and the subset of activated elements that are in the focus of attention. It is suggested that the activated portion has a time limit (as well as being susceptible to interference) whereas the focus of attention has a capacity limit. Some unresolved issues with that approach are discussed, along with the neurophysiology of short-term memory. The commonly-used term “working memory” is conceived as a combination of both short-term memory mechanisms, along with direction from central executive processes.

This chapter reviews over thirty years of findings from behavioral neurophysiological recordings in the monkey hippocampus. It shows that consistent with the memory space hypothesis, hippocampal neurons provide a rich array of responses that signal all aspects of the ongoing memory trial. It also discuss more recent studies showing strong associative learning signals as well as long-term memory signals in the monkey hippocampus that provide further insight into the plastic and mnemonic properties of hippocampal neurons.

This chapter reviews research examining visual memory for complex, natural environments. It is divided into two main sections. The first concerns the use of visual memory to construct online representations of natural scenes (i.e., the representation produced as one is actively viewing a scene). The second concerns longer-term scene memory stored after a scene is no longer in view.

This chapter discusses neuropsychological disorders of visual short-term memory (VSTM) and the importance of these disorders for theories of VSTM. It emphasizes the role of VSTM not only in “bottom-up” processes (forming a memory for new material from the environment) but also in “top-down” processing, as when visual images are formed from material from long-term memory (LTM). It is argued that just as VSTM is involved when we need to remember new visual input, so visual imagery recruits VSTM, which then serves as a medium for retrieving stored visual memories. Thus, the same processes (and brain regions) that play a part in typical laboratory studies of VSTM using relatively simple visual displays may also be involved when people make judgments about the visual characteristics of objects retrieved from LTM.

This chapter summarizes the various visual memory systems that are discussed in this book, focusing on the nature of the representations used by these systems, their temporal dynamics, their neutral substrates, and their functional role in visually guided behavior. It discusses the definition of visual memory. It then describes the three main subsystems of visual memory: visual sensory memory, visual short-term memory (VSTM), and long-term memory (LTM).

This chapter discusses visual short-term memory (VSTM) system. It compares VSTM system with visual long-term memory system. It then discusses the measurement of VSTM, the storage capacity of VSTM, the reasons why VSTM capacity is limited, the nature of VSTM representations, VSTM processes, and the functions of the VSTM process.

This chapter discusses the executive functions of the prefrontal cortex against the background of its position in the neocortical map of cognitive representations. It attempts to place prefrontal functions within the broad framework of the cortical substrate of long-term memory, which is formed by a complex array of widely distributed, overlapping, and intersecting neuronal networks in the neocortex of association. The chapter then presents a conceptual model of the distribution of long-term memory in the neocortex. The chapter concludes with a brief discussion of microelectrode data from the lateral prefrontal cortex that not only reaffirm the anchoring of its functions in long-term memory but also provide insight into the mechanisms of temporal integration, which is cardinal among those functions.

To understand how humans use rules to determine actions, it is critical to learn more about how they select responses on the basis of associations in long‐term memory. This chapter discusses what has been learned thus far about the neural substrates of rule storage, retrieval, and maintenance. This chapter presents evidence that rule knowledge associated with environmental cues is stored in areas of the posterior temporal lobes, such as the middle temporal gyrus. It also provides evidence that ventrolateral prefrontal cortex is engaged in the effortful retrieval of rule meanings from long‐term memory. During initial rule retrieval, there is some evidence that different brain structures are recruited, depending on the type of rule retrieved. In contrast, during rule maintenance, brain activation in prefrontal cortex and other brain regions appears to be sensitive to the amount of information to be held in mind, rather than the type of rule or instructional cue.

Ivan Izquierdo and his coworkers demonstrated the main molecular steps of memory consolidation for one-trial avoidance and other tasks in the hippocampus and other brain areas, the separation of short- and long-term memory, and the main mechanisms of extinction and memory persistence. Izquierdo trained over 90 graduate students, established memory research in Brazil and Argentina, and set up several centers of excellence in Neuroscience in those countries.

Visual sensory memory lasts for the duration of the response in the retina. Visual short-term memory may comprise up to 10 objects during the first second, and drops to 4 after that. Only a few items can be remembered from the scene before a saccade and carried forward to be combined with the scene seen after a saccade. What is remembered is affected by where attention is directed. Visual long-term memory may last a lifetime, and it can be divided into declarative and nondeclarative, with further subdivisions. Traces of memory are found all over the visual system, particularly in the temporal lobe for declarative memory but also in lower areas.

This chapter shows that the frontal lobes play an important role in integrating information from many other areas of the brain, and are crucially involved in its manipulation for purposes such as learning, comprehension, and reasoning. Given that these are precisely the roles attributed to working memory, it seems likely that the functional and anatomical approaches will continue to develop synergistically, as the complex functions assigned to working memory are tackled using an increasingly sophisticated armory of new psychological and neurobiological techniques.

This chapter describes what concepts are taken to be in psychology and identifies the goals of the psychological theories of concepts. In psychology, concepts are characterized as being those bodies of knowledge that are stored in long-term memory and that are used by default in the processes underlying most, if not all, higher cognitive competences when they result in judgments about the referents of these concepts. Theories of concepts attempt to describe the knowledge stored in concepts, the format of concepts, the cognitive processes that use concepts, the acquisition of concepts, and the localization of concepts in the brain. By doing so, they can explain the properties of people's higher cognitive competences. Alternative characterizations of concepts by Prinz, Barsalou, and Dennett are criticized.

This chapter summarizes the main issues that have divided researchers in the field of working memory and provides an integrated account of what we have learned about working memory. The main issues of contention include the capacity of working memory, the gateway hypothesis, and the phonological loop. The findings of the study in this book reveal that working memory is a complex system responsible for the temporary storage and processing of information, and that it is structurally and functionally distinct from different forms of permanent or long-term memory.