The two-process theory of detection, search, and attention presented by Schneider and Shiffrin is tested and extended in a series of experiments. The studies demonstrate the qualitative difference between two modes of information processing: automatic detection and controlled search. They trace the course of the learning of automatic detection, of categories, and of automaticattention responses. They show the dependence of automatic detection on attending responses and demonstrate how such responses interrupt controlled processing and interfere with the focusing of attention. The learning of categories is shown to improve controlled search performance. A general framework for human information processing is proposed; the framework emphasizes the roles of automatic and controlled processing. The theory is compared to and contrasted with extant models of search and attention.

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Early and late selection models of attention disagree about whether visual objects are identified before or after selection, with recent evidence of interference from to-be-ignored stimuli favoring late selection over early selection accounts. However, these tests may not have permitted optimal attentional focusing. In 4 experiments subjects identified an attentionally cued target letter embedded among distractors. Only minimal effects of information appearing in to-be-ignored locations were observed. This striking efficiency of selection provides support for early selection theories and calls into question some late selection theories holding that stimuli throughout the display are immediately and fully identified prior to attentional selection. In order to explain the larger pattern of results across a variety of focused- and divided-attention paradigms, a hybrid model is advanced with a flexible locus for visual selection. Among the most fundamental questions about the func-tional architecture of the human visual information-process-ing system is the locus of selective attention. Of particular importance is whether attentional limitations occur before stimulus identification (as assumed in early selection theories)

In the single-store model of memory, the enhanced recall for the last items in a free-recall task (i.e., the recency effect) is understood to reflect a general property of memory rather than a separate short-term store. This interpretation is supported by the finding of a long-term recency effect under conditions that eliminate the contribution from the short-term store. In this article, evidence is reviewed showing that recency effects in the short and long terms have different properties, and it is suggested that 2 memory components are needed to account for the recency effects: an episodic contextual system with changing context and an activation-based short-term memory buffer that drives the encoding of item–context associations. A neurocomputational model based on these 2 components is shown to account for previously observed dissociations and to make novel predictions, which are confirmed in a set of experiments.

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We explore the role of negative relationships in the context of social networks in work organizations. Though network researchers have emphasized the benefits and opportunities derived from positive interpersonal relationships, we examine the social liabilities that can result from negative relationships in order to flesh out the entire “social ledger. ” We define a negative relationship as an enduring, recurring set of negative judgments, feelings, and behavioral intentions towards another person – one person dislikes another. We identify the factors that lead to negative relationships in the workplace as well as factors that may moderate the relationship between negative relationships and individuals ’ task and socioemotional outcomes. We argue that these negative relationships may have greater power than positive relationships to explain workplace outcomes. We derive our argument from theory and research on negative asymmetry. Negative Relationships in Networks 3 “A man’s stature is determined by his enemies, not his friends. ”-- Al Pacino, City Hall Employees in organizations are embedded in social networks that can provide opportunities and benefits such as job attainment, job satisfaction, performance, salary, power, and promotions

Spelke, Hirst, and Neisser trained two subjects to copy unrelated words at dictation as they read and understood stories. The subjects ' success was interpreted as evidence against the hypothesis of a fixed attentional capacity or limited cognitive resources; instead, it was hypothesized, attention is a skill that improves with practice. However, other explanations of these results can be proposed. The present research addressed two such counterhypotheses: that capacity may be alternated between reading and writing and that the writing task may become "automatic," and require no capacity at all. Experiment 1 was designed to see whether subjects take intermittent advantage of the redundancy of the stories to switch to the writing task. Some subjects were trained to copy words while reading highly redundant material (short stories); others were trained with less redundant encyclopedia articles. On reaching criterion, each subject was switched to the other type of reading material. Three of the four subjects trained with stories transferred their skill immediately to the encyclopedia, suggesting that they had not been using the redundancy of the stories to accomplish

The model of a single central bottleneck for human information processing is critically examined. Most evidence cited in support of the model has been observed within the overlapping tasks paradigm. It is shown here that most findings obtained within that paradigm and that were used to support the model are also consistent with a simple resource model. The most prominent findings are the millisecondfor-millisecond slope at the left of the RT2–SOA curve, the high RT1–RT2 correlation, the additivity of the effects on RT2 of SOA and of the difficulty of selecting R2, and the washout of the effect of S2 discriminability on RT2 in a dual-task condition. In addition, the asymmetry of the effects of the dual-task requirement on RT1 and RT2 can be accounted for by the resource model provided that it assumes uneven allocation of resources, which is quite reasonable in view of the task asymmetry inherent in the demand characteristics of the paradigm. The same is true for two other findings that appear to support the single-bottleneck model—that in the dual-task condition, the demand of the first task affects equally RT1 and RT2 and that its effect on RT1 is the same as the corresponding effect in the singletask

This paper reviews the key issues in hypermedia systems as an overture to the proposal of a new semiotic paradigm for hypermedia data and coding models. The hypertext concept permits users to interact with and manage data as high-level conceptual objects rather than as symbol streams. Current hypermedia systems can best be defined as an amalgamation of hypertext and multimedia. While the hypertext data model enables this goal, that is not true for the data models of other media forms. A new semiotic paradigm that addresses these deficiencies and supports object-oriented interaction with compressed multimedia streams is proposed. This paper initially presents an overview of the hypertext data model, contrasting it with existing multimedia data and coding models. The framework for the new paradigm is then presented in a brief review of cognitive, psychological, and semiotic principles. This analysis culminates in the proposal of semiotically based data models and representations predisposed to the hypermedia paradigm. Keywords—Audio coding, data models, hypermedia, hypertext systems, image coding, information retrieval, multimedia information systems, psychology, semiotics, signal representations, source coding. I.