Publications

Abstract

In languages in which nouns have a grammatical gender, word recognition can be estimated by gender decision response times. Although gender decision has yet to be used extensively, it has proved sensitive to several factors that have been shown to affect lexical access. The task is not restricted to spoken language but can be used with linguistic information from other sensory modalities.

Abstract

P. A. Starreveld and W. La Heij (1995) tested the seriality view of lexical access in speech production, according to which lexical selection and the encoding of a word's form proceed in serial order without feedback. In 2 experiments, they looked at the combined effect of semantic and orthographic relatedness of written distracter words in tasks that required conceptually driven naming. They found an interaction between semantic relatedness and orthographic relatedness and argued that the observed interaction refutes the seriality view of lexical access. In this comment, the authors argue that Starreveld and La Heij's rejection of serial access was based on an oversimplified conception of the seriality view and that interaction, rather than additivity, is predicted by existing conceptions of serial access.

Abstract

The structure of relative clauses has attracted considerable attention in recent years, and a number of authors have carried out analyses of the syntax of relativization. In our investigation of syntactic structure and change in New Guinea Tok Pisin, we find that the basic processes involved in relativization have much broader discourse functions, and that relativization is only a special instance of the application of general ‘bracketing’ devices used in the organization of information. Syntactic structure, in this case, can be understood as a component of, and derivative from, discourse structure.

Abstract

The CELEX lexical database includes a list of Dutch syllables and their frequencies, based on syllabification of isolated word forms. In connected speech, however, sentence-level phonological rules can modify the syllables and their token frequencies. In order to estimate the changes syllables may undergo in connected speech, an empirical investigation was carried out. A large Dutch text corpus (TROUW) was transcribed, processed by word level rules, and syllabified. The resulting lexeme syllables were evaluated by comparing them to the CELEX lexical database for Dutch. Then additional phonological sentence-level rules were applied to the TROUW corpus, and the frequencies of the resulting connected speech syllables were compared with those of the lexeme syllables from TROUW. The overall correlation between lexeme and speech syllables was very high. However, speech syllables generally had more complex CV structures than lexeme syllables. Implications of the results for research involving syllables are discussed. With respect to the notion of a mental syllabary (a store for precompiled articulatory programs for syllables, see Levelt & Wheeldon, 1994) this study revealed an interesting statistical result. The calculation of the cumulative syllable frequencies showed that 85% of the syllable tokens in Dutch can be covered by the 500 most frequent syllable types, which makes the idea of a syllabary very attractive.

Abstract

According to certain theories of language production, lexical access to a content word consists of two independent and serially ordered stages. In the first, semantically driven stage, so-called lemmas are retrieved, i.e., lexical items that are specified with respect to syntactic and semantic properties, but not with respect to phonological characteristics. In the second stage, the corresponding wordforms, the so-called lexemes, are retrieved. This implies that the access to a content word involves an early stage of exclusively semantic activation and a later stage of exclusively phonological activation. This seriality assumption was tested experimentally, using a picture-word interference paradigm in which the interfering words were presented auditorily. The results show an interference effect of semantically related words on picture naming latencies at an early SOA (− 150 ms), and a facilitatory effect of phonologically related words at later SOAs (0 ms, + 150 ms). On the basis of these results it can be concluded that there is indeed a stage of lexical access to a content word where only its meaning is activated, followed by a stage where only its form is activated. These findings can be seen as empirical support for a two-stage model of lexical access, or, alternatively, as putting constraints on the parameters in a network model of lexical access, such as the model proposed by Dell and Reich.

Abstract

Recent research in speech production has shown that syntactic structure is reflected in segmental phonology--the application of certain phonological rules of English (e.g., palatalization and alveolar flapping) is inhibited across phrase boundaries. We examined whether such segmental effects can be used in speech perception as cues to syntactic structure, and the relation between the use of these segmental features as syntactic markers in production and perception. Speakers of American English (a dialect in which the above segmental effects occur) could indeed use the segmental cues in syntax perception; speakers of British English (in which the effects do not occur) were unable to make use of them, while speakers of British English who were long-term residents of the United States showed intermediate performance.

Abstract

In his paper ‘On Horn's dilemma: presupposition and negation’ Burton-Roberts (1989a) presents an ambitious programme, formulated right at the outset. He seeks to establish three points: (i) Under the ‘standard logical definition of presupposition’ a pre-suppositional semantics is INCOMPATIBLE with a SEMANTICALLY AMBIGUOUS NEGATION operator (SAN), on pain of the theory being rendered ‘empirically empty and theoretically trivial’,. (ii) From this it follows that the one unambiguous negation is presupposition preserving. Cases that have been identified as presupposition-cancelling negation should be re-analysed as ‘instances of a pragmatic phenomenon’, not unlike what has been proposed in Horn (1985), that is as METALINGUISTIC NEGATION (MN). (iii) This pragmatic analysis of MN ‘itself implies a presuppositional semantics’, that is to say ‘a presuppositional theory of truth-value gaps’.

Abstract

The roles which word class (open/closed) and sentential stress play in the sentence comprehension processes of both agrammatic (Broca's) aphasics and normal listeners were examined with a word monitoring task. Overall, normal listeners responded more quickly to stressed than to unstressed items, but showed no effect of word class. Aphasics also responded more quickly to stressed than to unstressed materials, but, unlike the normals, responded faster to open than to closed class words regardless of their stress. The results are interpreted as support for the theory that Broca's aphasics lack the functional underlying open/closed class word distinction used in word recognition by normal listeners.

Abstract

Two experiments examined the nature of access, storage, and comprehension of idiomatic phrases. In both studies a Phrase Classification Task was utilized. In this, reaction times to determine whether or not word strings constituted acceptable English phrases were measured. Classification times were significantly faster to idiom than to matched control phrases. This effect held under conditions involving different categories of idioms, different transitional probabilities among words in the phrases, and different levels of awareness of the presence of idioms in the materials. The data support a Lexical Representation Hypothesis for the processing of idioms.

Abstract

An introductory study of the perception of stochastically specified events is reported. The initial problem was to determine whether the perceiver can split visual input data of this kind into random and determined components. The inability of subjects to do so with the stimulus material used (a filmlike sequence of dot patterns), led to the more general question of how subjects code this kind of visual material. To meet the difficulty of defining the subjects' responses, two experiments were designed. In both, patterns were presented as a rapid sequence of dots on a screen. The patterns were more or less disturbed by “noise,” i.e. the dots did not appear exactly at their proper places. In the first experiment the response was a rating on a semantic scale, in the second an identification from among a set of alternative patterns. The results of these experiments give some insight in the coding systems adopted by the subjects. First, noise appears to be detrimental to pattern recognition, especially to patterns with little spread. Second, this shows connections with the factors obtained from analysis of the semantic ratings, e.g. easily disturbed patterns show a large drop in the semantic regularity factor, when only a little noise is added.

Abstract

Computer simulations in an instructional context can be characterized according to four aspects (themes): simulation models, learning goals, learning processes and learner activity. The present paper provides an outline of these four themes. The main classification criterion for simulation models is quantitative vs. qualitative models. For quantitative models a further subdivision can be made by classifying the independent and dependent variables as continuous or discrete. A second criterion is whether one of the independent variables is time, thus distinguishing dynamic and static models. Qualitative models on the other hand use propositions about non-quantitative properties of a system or they describe quantitative aspects in a qualitative way. Related to the underlying model is the interaction with it. When this interaction has a normative counterpart in the real world we call it a procedure. The second theme of learning with computer simulation concerns learning goals. A learning goal is principally classified along three dimensions, which specify different aspects of the knowledge involved. The first dimension, knowledge category, indicates that a learning goal can address principles, concepts and/or facts (conceptual knowledge) or procedures (performance sequences). The second dimension, knowledge representation, captures the fact that knowledge can be represented in a more declarative (articulate, explicit), or in a more compiled (implicit) format, each one having its own advantages and drawbacks. The third dimension, knowledge scope, involves the learning goal's relation with the simulation domain; knowledge can be specific to a particular domain, or generalizable over classes of domains (generic). A more or less separate type of learning goal refers to knowledge acquisition skills that are pertinent to learning in an exploratory environment. Learning processes constitute the third theme. Learning processes are defined as cognitive actions of the learner. Learning processes can be classified using a multilevel scheme. The first (highest) of these levels gives four main categories: orientation, hypothesis generation, testing and evaluation. Examples of more specific processes are model exploration and output interpretation. The fourth theme of learning with computer simulations is learner activity. Learner activity is defined as the ‘physical’ interaction of the learner with the simulations (as opposed to the mental interaction that was described in the learning processes). Five main categories of learner activity are distinguished: defining experimental settings (variables, parameters etc.), interaction process choices (deciding a next step), collecting data, choice of data presentation and metacontrol over the simulation.

Abstract

The use of computer simulations in education and training can have substantial advantages over other approaches. In comparison with alternatives such as textbooks, lectures, and tutorial courseware, a simulation-based approach offers the opportunity to learn in a relatively realistic problem-solving context, to practise task performance without stress, to systematically explore both realistic and hypothetical situations, to change the time-scale of events, and to interact with simplified versions of the process or system being simulated. However, learners are often unable to cope with the freedom offered by, and the complexity of, a simulation. As a result many of them resort to an unsystematic, unproductive mode of exploration. There is evidence that simulation-based learning can be improved if the learner is supported while working with the simulation. Constructing such an instructional environment around simulations seems to run counter to the freedom the learner is allowed to in ‘stand alone’ simulations. The present article explores instructional measures that allow for an optimal freedom for the learner. An extensive discussion of learning goals brings two main types of learning goals to the fore: conceptual knowledge and operational knowledge. A third type of learning goal refers to the knowledge acquisition (exploratory learning) process. Cognitive theory has implications for the design of instructional environments around simulations. Most of these implications are quite general, but they can also be related to the three types of learning goals. For conceptual knowledge the sequence and choice of models and problems is important, as is providing the learner with explanations and minimization of error. For operational knowledge cognitive theory recommends learning to take place in a problem solving context, the explicit tracing of the behaviour of the learner, providing immediate feedback and minimization of working memory load. For knowledge acquisition goals, it is recommended that the tutor takes the role of a model and coach, and that learning takes place together with a companion. A second source of inspiration for designing instructional environments can be found in Instructional Design Theories. Reviewing these shows that interacting with a simulation can be a part of a more comprehensive instructional strategy, in which for example also prerequisite knowledge is taught. Moreover, information present in a simulation can also be represented in a more structural or static way and these two forms of presentation provoked to perform specific learning processes and learner activities by tutor controlled variations in the simulation, and by tutor initiated prodding techniques. And finally, instructional design theories showed that complex models and procedures can be taught by starting with central and simple elements of these models and procedures and subsequently presenting more complex models and procedures. Most of the recent simulation-based intelligent tutoring systems involve troubleshooting of complex technical systems. Learners are supposed to acquire knowledge of particular system principles, of troubleshooting procedures, or of both. Commonly encountered instructional features include (a) the sequencing of increasingly complex problems to be solved, (b) the availability of a range of help information on request, (c) the presence of an expert troubleshooting module which can step in to provide criticism on learner performance, hints on the problem nature, or suggestions on how to proceed, (d) the option of having the expert module demonstrate optimal performance afterwards, and (e) the use of different ways of depicting the simulated system. A selection of findings is summarized by placing them under the four themes we think to be characteristic of learning with computer simulations (see de Jong, this volume).

Abstract

As a preliminary to further research on musical consonance an explanatory investigation was made on the different modes of judgment of musical intervals. This was done by way of a semantic differential. Subjects rated 23 intervals against 10 scales. In a factor analysis three factors appeared: pitch, evaluation and fusion. The relation between these factors and some physical characteristics has been investigated. The scale consonant-dissonant showed to be purely evaluative (in opposition to Stumpf's theory). This evaluative connotation is not in accordance with the musicological meaning of consonance. Suggestions to account for this difference have been given.

Abstract

Dichoptic mixtures of equiluminous components of different wavelengths were matched with a binocularly presented "monocular" mixture of appropriate chosen amounts of the same colour components. Stimuli were chosen from the region of 490-630 nm. Although satisfactory colour matches could be obtained, dichoptic mixtures differed from normal mixtures to a considerable extent. Midspectral stimuli tended to be more dominant in the dichoptic mixtures than either short or long wavelength stimuli. An attempt was made to describe the relation between monocular and dichoptic mixtures with one function containing a wavelength variable and an eye dominance parameter.

Abstract

A combination of Southern blot analysis on a panel of tumor-derived somatic cell hybrids and fluorescence in situ hybridization techniques was used to map YACs, cosmids and DNA markers from the Xp11.2 region relative to the X chromosome breakpoint of the renal cell carcinoma-associated t(X;1)(p11;q21). The position of the breakpoint could be determined as follows: Xcen-OATL2-DXS146-DXS255-SYP-t(X;1)-TFE 3-OATL1-Xpter. Fluorescence in situ hybridization experiments using TFE3-containing YACs and cosmids revealed split signals indicating that the corresponding DNA inserts span the breakpoint region. Subsequent Southern blot analysis showed that a 2.3-kb EcoRI fragment which is present in all TFE3 cosmids identified, hybridizes to aberrant restriction fragments in three independent t(X;1)-positive renal cell carcinoma DNAs. The breakpoints in these tumors are not the same, but map within a region of approximately 6.5 kb. Through preparative gel electrophoresis an (X;1) chimaeric 4.4-kb EcoRI fragment could be isolated which encompasses the breakpoint region present on der(X). Preliminary characterization of this fragment revealed the presence of a 150-bp region with a strong homology to the 5' end of the mouse TFE3 cDNA in the X-chromosome part, and a 48-bp segment in the chromosome 1-derived part identical to the 5' end of a known EST (accession number R93849). These observations suggest that a fusion gene is formed between the two corresponding genes in t(X;1)(p11;q21)-positive papillary renal cell carcinomas.