Preparing words in speech production is normally a fast and accurate process. We generate them two or three per second in fluent conversation; and overtly naming a clear picture of an object can easily be initiated within 600 msec after picture onset. The underlying process, however, is exceedingly complex. The theory reviewed in this target article analyzes this process as staged and feedforward. After a first stage of conceptual preparation, word generation proceeds through lexical selection, morphological and phonological encoding, phonetic (...) encoding, and articulation itself. In addition, the speaker exerts some degree of output control, by monitoring of self-produced internal and overt speech. The core of the theory, ranging from lexical selection to the initiation of phonetic encoding, is captured in a computational model, called WEAVER++. Both the theory and the computational model have been developed in interaction with reaction time experiments, particularly in picture naming or related word production paradigms, with the aim of accounting for the real-time processing in normal word production. A comprehensive review of theory, model, and experiments is presented. The model can handle some of the main observations in the domain of speech errors (the major empirical domain for most other theories of lexical access), and the theory opens new ways of approaching the cerebral organization of speech production by way of high-temporal-resolution imaging. (shrink)

Levelt, reviewing the AGL field from a psycholinguistic perspective, identifies various gaps and makes a number of concrete suggestions for improving several currently used experimental designs. He raises the question whether artificial (and natural) grammar learning is about detecting ‘rules’, as is commonly assumed, or rather the detection of a set of ‘constraints’. He cautions the community to not ignore ‘semantics’, and recommends to consider less artificial tasks, that may be needed for learning more complex rules by human or (...) nonhuman animals. (shrink)

In his paper, MacKay reviews his Node Structure theory of error detection, but precedes it with a critical discussion of the Perceptual Loop theory of self-monitoring proposed in Levelt . The present commentary is concerned with this latter critique and shows that there are more than casual problems with MacKay's argumentation.

The commentaries provide a multitude of perspectives on the theory of lexical access presented in our target article. We respond, on the one hand, to criticisms that concern the embeddings of our model in the larger theoretical frameworks of human performance and of a speaker's multiword sentence and discourse generation. These embeddings, we argue, are either already there or naturally forgeable. On the other hand, we reply to a host of theory-internal issues concerning the abstract properties of our feedforward spreading (...) activation model, which functions without the usual cascading, feedback, and inhibitory connections. These issues also concern the concrete stratification in terms of lexical concepts, syntactic lemmas, and morphophonology. Our response stresses the parsimony of our modeling in the light of its substantial empirical coverage. We elaborate its usefulness for neuroimaging and aphasiology and suggest further cross-linguistic extensions of the model. (shrink)

How can one conceive of the neuronal implementation of the processing model we proposed in our target article? In his commentary (Pulvermüller 1999, reprinted here in this issue), Pulvermüller makes various proposals concerning the underlying neural mechanisms and their potential localizations in the brain. These proposals demonstrate the compatibility of our processing model and current neuroscience. We add further evidence on details of localization based on a recent meta-analysis of neuroimaging studies of word production (Indefrey & Levelt 2000). We (...) also express some minor disagreements with respect to Pulvermüller's interpretation of the “lemma” notion, and concerning his neural modeling of phonological code retrieval. Branigan & Pickering discuss important aspects of syntactic encoding, which was not the topic of the target article. We discuss their well-taken proposal that multiple syntactic frames for a single verb lemma are represented as independent nodes, which can be shared with other verbs, such as accounting for syntactic priming in speech production. We also discuss how, in principle, the alternative multiple-frame-multiple-lemma account can be tested empirically. The available evidence does not seem to support that account. Footnotes1 BBS Note: The original manuscript of this Response article was received on January 14, 2000. (shrink)

This commentary discusses whether abstract metrical frames are stored. For stress-assigning languages (e.g., Dutch and English), which have a dominant stress pattern, metrical frames are stored only for words that deviate from the default stress pattern. The majority of the words in these languages are produced without retrieving any independent syllabic or metrical frame.

It is a major move from the claim that the core linguistic problem in Broca's aphasia is the inability to deal with traces, to the claim that this is the syntactic operation only and that it is exclusively supported by Broca's region. Three arguments plead against this move. First, many Broca patients have no damage to Broca's area. Second, it is not only passive, but also active jabberwocky sentences that activate the frontal operculum in a judgment task. Third, the same (...) area is involved in a phrase-building production task that does not require tense processing. (shrink)

A comparison of Merge, a model of comprehension, and WEAVER, a model of production, raises five issues: merging models of comprehension and production necessarily creates feedback; neither model is a comprehensive account of word processing; the models are incomplete in different ways; the models differ in their handling of competition; as opposed to WEAVER, Merge is a model of metalinguistic behavior.

Artificial grammar learning (AGL) is used to study how human adults, infants, animals or machines learn various sorts of rules defined over sounds or visual items. Ten Cate et al. introduce the topic and provide a critical synthesis of this important interdisciplinary area of research. They identify the questions that remain open and the challenges that lie ahead, and argue that the limits of human, animal and machine learning abilities have yet to be found.

A concise yet rigorous introduction to logic and discrete mathematics. This book features a unique combination of comprehensive coverage of logic with a solid exposition of the most important fields of discrete mathematics, presenting material that has been tested and refined by the authors in university courses taught over more than a decade. The chapters on logic - propositional and first-order - provide a robust toolkit for logical reasoning, emphasizing the conceptual understanding of the language and the semantics of classical (...) logic as well as practical applications through the easy to understand and use deductive systems of Semantic Tableaux and Resolution. The chapters on set theory, number theory, combinatorics and graph theory combine the necessary minimum of theory with numerous examples and selected applications. Written in a clear and reader-friendly style, each section ends with an extensive set of exercises, most of them provided with complete solutions which are available in the accompanying solutions manual. Key Features: Suitable for a variety of courses for students in both Mathematics and Computer Science. Extensive, in-depth coverage of classical logic, combined with a solid exposition of a selection of the most important fields of discrete mathematics Concise, clear and uncluttered presentation with numerous examples. Covers some applications including cryptographic systems, discrete probability and network algorithms. Logic and Discrete Mathematics: A Concise Introduction is aimed mainly at undergraduate courses for students in mathematics and computer science, but the book will also be a valuable resource for graduate modules and for self-study. (shrink)

Experientialist accounts of wellbeing are those accounts of wellbeing that subscribe to the experience requirement. Typically, these accounts are hedonistic. In this article I present the claim that hedonism is not the most plausible experientialist account of wellbeing. The value of experience should not be understood as being limited to pleasure, and as such, the most plausible experientialist account of wellbeing is pluralistic, not hedonistic. In support of this claim, I argue first that pleasure should not be understood as a (...) broad term to describe valuable experiences generally. I then analyze responses to the main argument against a monistic view on the value of experience: the philosophy of swine objection. I argue that such responses deviate from the central hedonistic view that only pleasure and pain matter for wellbeing. I then argue that the argument can be avoided on a pluralistic account, and formulate a plausible candidate for an account of pluralistic experientialism, in which, besides pleasure, non-hedonic aspects of experience like novelty, compassion, and aesthetic value also contribute to wellbeing. (shrink)