Publications

Abstract

In this article, we present the spatial logistics task (SLOT) platform for investigating multimodal communication between 2 human participants. Presented are the SLOT communication task and the software and hardware that has been developed to run SLOT experiments and record the participants’ multimodal behavior. SLOT offers a high level of flexibility in varying the context of the communication and is particularly useful in studies of the relationship between pen gestures and speech. We illustrate the use of the SLOT platform by discussing the results of some early experiments. The first is an experiment on negotiation with a one-way mirror between the participants, and the second is an exploratory study of automatic recognition of spontaneous pen gestures. The results of these studies demonstrate the usefulness of the SLOT platform for conducting multimodal communication research in both human– human and human–computer interactions.

Abstract

Participants' eye movements were monitored as they heard sentences and saw four pictured objects on a computer screen. Participants were instructed to click on the object mentioned in the sentence. There were more transitory fixations to pictures representing monosyllabic words (e.g. ham) when the first syllable of the target word (e.g. hamster) had been replaced by a recording of the monosyllabic word than when it came from a different recording of the target word. This demonstrates that a phonemically identical sequence can contain cues that modulate its lexical interpretation. This effect was governed by the duration of the sequence, rather than by its origin (i.e. which type of word it came from). The longer the sequence, the more monosyllabic-word interpretations it generated. We argue that cues to lexical-embedding disambiguation, such as segmental lengthening, result from the realization of a prosodic boundary that often but not always follows monosyllabic words, and that lexical candidates whose word boundaries are aligned with prosodic boundaries are favored in the word-recognition process.

Abstract

This letter evaluates potential benefits of combining human speech recognition ~HSR! and automatic speech recognition by building a joint model of an automatic phone recognizer ~APR! and a computational model of HSR, viz., Shortlist @Norris, Cognition 52, 189–234 ~1994!#. Experiments based on ‘‘real-life’’ speech highlight critical limitations posed by some of the simplifying assumptions made in models of human speech recognition. These limitations could be overcome by avoiding hard phone decisions at the output side of the APR, and by using a match between the input and the internal lexicon that flexibly copes with deviations from canonical phonemic representations.

Abstract

In this paper, we present an automatic speech recognition (ASR) system based on the combination of an automatic phone recogniser and a computational model of human speech recognition – SpeM – that is capable of computing ‘word activations’ during the recognition process, in addition to doing normal speech recognition, a task in which conventional ASR architectures only provide output after the end of an utterance. We explain the notion of word activation and show that it can be used for ‘early recognition’, i.e. recognising a word before the end of the word is available. Our ASR system was tested on 992 continuous speech utterances, each containing at least one target word: a city name of at least two syllables. The results show that early recognition was obtained for 72.8% of the target words that were recognised correctly. Also, it is shown that word activation can be used as an effective confidence measure.

Abstract

We have recently developed a new model of human speech recognition, based on automatic speech recognition techniques [1]. The present paper has two goals. First, we show that the new model performs well in the recognition of lexically ambiguous input. These demonstrations suggest that the model is able to operate in the same optimal way as human listeners. Second, we discuss how to relate the behaviour of a recogniser, designed to discover the optimum path through a word lattice, to data from human listening experiments. We argue that this requires a metric that combines both path-based and word-based measures of recognition performance. The combined metric varies continuously as the input speech signal unfolds over time.

Abstract

In this paper, we present a novel computational model of human speech recognition – called SpeM – based on the theory underlying Shortlist. We will show that SpeM, in combination with an automatic phone recogniser (APR), is able to simulate the human speech recognition process from the acoustic signal to the ultimate recognition of words. This joint model takes an acoustic speech file as input and calculates the activation flows of candidate words on the basis of the degree of fit of the candidate words with the input. Experiments showed that SpeM outperforms Shortlist on the recognition of ‘real-life’ input. Furthermore, SpeM performs only slightly worse than an off-the-shelf full-blown automatic speech recogniser in which all words are equally probable, while it provides a transparent computationally elegant paradigm for modelling word activations in human word recognition.

Abstract

During language production and comprehension, information about a word's syntactic properties is sometimes needed. While the decision about the grammatical gender of a word requires access to syntactic knowledge, it has also been hypothesized that semantic (i.e., biological gender) or phonological information (i.e., sound regularities) may influence this decision. Event-related potentials (ERPs) were measured while native speakers of German processed written words that were or were not semantically and/or phonologically marked for gender. Behavioral and ERP results showed that participants were faster in making a gender decision when words were semantically and/or phonologically gender marked than when this was not the case, although the phonological effects were less clear. In conclusion, our data provide evidence that even though participants performed a grammatical gender decision, this task can be influenced by semantic and phonological factors.

Abstract

This study investigated the time course of phonological encoding during speech production planning. Previous research has shown that conceptual/semantic information precedes syntactic information in the planning of speech production and that syntactic information is available earlier than phonological information. Here, we studied the relative time courses of the two different processes within phonological encoding, i.e. metrical encoding and syllabification. According to one prominent theory of language production, metrical encoding involves the retrieval of the stress pattern of a word, while syllabification is carried out to construct the syllabic structure of a word. However, the relative timing of these two processes is underspecified in the theory. We employed an implicit picture naming task and recorded event-related brain potentials to obtain fine-grained temporal information about metrical encoding and syllabification. Results revealed that both tasks generated effects that fall within the time window of phonological encoding. However, there was no timing difference between the two effects, suggesting that they occur approximately at the same time.

Abstract

In this study, we investigated grammatical feature selection during noun phrase production in German and Dutch. More specifically, we studied the conditions under which different grammatical genders select either the same or different determiners or suffixes. Pictures of one or two objects paired with a gender-congruent or a gender-incongruent distractor word were presented. Participants named the pictures using a singular or plural noun phrase with the appropriate determiner and/or adjective in German or Dutch. Significant effects of gender congruency were only obtained in the singular condition where the selection of determiners is governed by the target’s gender, but not in the plural condition where the determiner is identical for all genders. When different suffixes were to be selected in the gender-incongruent condition, no gender congruency effect was obtained. The results suggest that the so-called gender congruency effect is really a determiner congruency effect. The overall pattern of results is interpreted as indicating that grammatical feature selection is an automatic consequence of lexical node selection and therefore not subject to interference from other grammatical features. This implies that lexical node and grammatical feature selection operate with distinct principles.

Abstract

This study investigated the encoding of metrical information during speech production in Dutch. In Experiment 1, participants were asked to judge whether bisyllabic picture names had initial or final stress. Results showed significantly faster decision times for initially stressed targets (e.g., LEpel 'spoon') than for targets with final stress (e.g., liBEL 'dragon fly'; capital letters indicate stressed syllables) and revealed that the monitoring latencies are not a function of the picture naming or object recognition latencies to the same pictures. Experiments 2 and 3 replicated the outcome of the first experiment with bi- and trisyllabic picture names. These results demonstrate that metrical information of words is encoded rightward incrementally during phonological encoding in speech production. The results of these experiments are in line with Levelt's model of phonological encoding.

Abstract

A series of experiments was carried out to investigate the syllable affiliation of intervocalic consonants following short vowels, long vowels, and schwa in Dutch. Special interest was paid to words such as letter ['leter] ''id.,'' where a short vowel is followed by a single consonant. On phonological grounds one may predict that the first syllable should always be closed, but earlier psycholinguistic research had shown that speakers tend to leave these syllables open. In our experiments, bisyllabic word forms were presented aurally, and participants produced their syllables in reversed order (Experiments 1 through 5), or repeated the words inserting a pause between the syllables (Experiment 6). The results showed that participants generally closed syllables with a short vowel. However, in a significant number of the cases they produced open short vowel syllables. Syllables containing schwa, like syllables with a long vowel, were hardly ever closed. Word stress, the phonetic quality of the vowel in the first syllable, and the experimental context influenced syllabification. Taken together, the experiments show that native speakers syllabify bisyllabic Dutch nouns in accordance with a small set of prosodic output constraints. To account for the variability of the results, we propose that these constraints differ in their probabilities of being applied.

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

The basic idea behind this task is to find out how languages encode basic shape distinctions such as dimensionality, axial geometry, relative size, etc. More specifically, we want to find out (i) which formal means are used cross linguistically to encode basic shape distinctions, and (ii) which are the semantic distinctions that are made in this domain. In languages with many shape-classifiers, these distinctions are encoded (at least partially) in classifiers. In other languages, positional verbs, descriptive modifiers, such as “flat”, “round”, or nouns such as “cube”, “ball”, etc. might be the preferred means. In this context, we also want to investigate what other “grammatical work” shapeencoding expressions possibly do in a given language, e.g. unitization of mass nouns, or anaphoric uses of shape-encoding classifiers, etc. This task further seeks to determine the role of shape-related parameters which underlie the design of objects in the semantics of the system under investigation.

Abstract

This project aims to investigate how speakers of various languages in indigenous cultures verbally reason about moral issues. The ways in which a solution for a moral problem is found, phrased and justified will be taken as the basis for researching reasoning processes that manifest themselves verbally in the speakers’ arguments put forward to solve a number of moral problems which will be presented to them in the form of unfinished story plots or scenarios that ask for a solution. The plots chosen attempt to present common problems in human society and human behaviour. They should function to elicit moral discussion and/or moral arguments in groups of consultants of at least three persons.

Abstract

Three experiments examined whether infants recognise functors in phrases, and whether their representations of functors are phonetically well specified. Eight- and 13- month-old English infants heard monosyllabic lexical words preceded by real functors (e.g., the, his) versus nonsense functors (e.g., kuh); the latter were minimally modified segmentally (but not prosodically) from real functors. Lexical words were constant across conditions; thus recognition of functors would appear as longer listening time to sequences with real functors. Eightmonth- olds' listening times to sequences with real versus nonsense functors did not significantly differ, suggesting that they did not recognise real functors, or functor representations lacked phonetic specification. However, 13-month-olds listened significantly longer to sequences with real functors. Thus, somewhere between 8 and 13 months of age infants learn familiar functors and represent them with segmental detail. We propose that accumulated frequency of functors in input in general passes a critical threshold during this time.

Abstract

Aboriginal languages threatened by speakers poor economic and social conditions; some may survive through support for community development, language maintenance, bilingual education and training of Aboriginal teachers and linguists, and nonAboriginal teachers of Aboriginal and Islander students.

Abstract

Incremental sentence generation imposes special constraints on the representation of the grammar and the design of the formulator (the module which is responsible for constructing the syntactic and morphological structure). In the model of natural speech production presented here, a formalism called Segment Grammar is used for the representation of linguistic knowledge. We give a definition of this formalism and present a formulator design which relies on it. Next, we present an object- oriented implementation of Segment Grammar. Finally, we compare Segment Grammar with other formalisms.

Abstract

We present the results of a large-scale study on speech perception, assessing the number and type of perceptual hypotheses which listeners entertain about possible phoneme sequences in their language. Dutch listeners were asked to identify gated fragments of all 1179 diphones of Dutch, providing a total of 488 520 phoneme categorizations. The results manifest orderly uptake of acoustic information in the signal. Differences across phonemes in the rate at which fully correct recognition was achieved arose as a result of whether or not potential confusions could occur with other phonemes of the language ~long with short vowels, affricates with their initial components, etc.!. These data can be used to improve models of how acoustic phonetic information is mapped onto the mental lexicon during speech comprehension.

Abstract

Finnish vowel harmony rules require that if the vowel in the first syllable of a word belongs to one of two vowel sets, then all subsequent vowels in that word must belong either to the same set or to a neutral set. A harmony mismatch between two syllables containing vowels from the opposing sets thus signals a likely word boundary. We report five experiments showing that Finnish listeners can exploit this information in an on-line speech segmentation task. Listeners found it easier to detect words likehymyat the end of the nonsense stringpuhymy(where there is a harmony mismatch between the first two syllables) than in the stringpyhymy(where there is no mismatch). There was no such effect, however, when the target words appeared at the beginning of the nonsense string (e.g.,hymypuvshymypy). Stronger harmony effects were found for targets containing front harmony vowels (e.g.,hymy) than for targets containing back harmony vowels (e.g.,paloinkypaloandkupalo). The same pattern of results appeared whether target position within the string was predictable or unpredictable. Harmony mismatch thus appears to provide a useful segmentation cue for the detection of word onsets in Finnish speech.

Abstract

Spoken language comprehension requires rapid integration of information from multiple linguistic sources. In the present study we addressed the temporal aspects of this integration process by focusing on the time course of the selection of the appropriate meaning of lexical ambiguities (“bank”) in sentence contexts. Successful selection of the contextually appropriate meaning of the ambiguous word is dependent upon the rapid binding of the contextual information in the sentence to the appropriate meaning of the ambiguity. We used the N400 to identify the time course of this binding process. The N400 was measured to target words that followed three types of context sentences. In the concordant context, the sentence biased the meaning of the sentence-final ambiguous word so that it was related to the target. In the discordant context, the sentence context biased the meaning so that it was not related to the target. In the unrelated control condition, the sentences ended in an unambiguous noun that was unrelated to the target. Half of the concordant sentences biased the dominant meaning, and the other half biased the subordinate meaning of the sentence-final ambiguous words. The ISI between onset of the target word and offset of the sentence-final word of the context sentence was 100 ms in one version of the experiment, and 1250 ms in the second version. We found that (i) the lexically dominant meaning is always partly activated, independent of context, (ii) initially both dominant and subordinate meaning are (partly) activated, which suggests that contextual and lexical factors both contribute to sentence interpretation without context completely overriding lexical information, and (iii) strong lexical influences remain present for a relatively long period of time.

Abstract

In this study the N400 component of the event-related potential was used to investigate spoken sentence understanding in Broca's and Wernicke's aphasics. The aim of the study was to determine whether spoken sentence comprehension problems in these patients might result from a deficit in the on-line integration of lexical information. Subjects listened to sentences spoken at a normal rate. In half of these sentences, the meaning of the final word of the sentence matched the semantic specifications of the preceding sentence context. In the other half of the sentences, the sentence-final word was anomalous with respect to the preceding sentence context. The N400 was measured to the sentence-final words in both conditions. The results for the aphasic patients (n = 14) were analyzed according to the severity of their comprehension deficit and compared to a group of 12 neurologically unimpaired age-matched controls, as well as a group of 6 nonaphasic patients with a lesion in the right hemisphere. The nonaphasic brain damaged patients and the aphasic patients with a light comprehension deficit (high comprehenders, n = 7) showed an N400 effect that was comparable to that of the neurologically unimpaired subjects. In the aphasic patients with a moderate to severe comprehension deficit (low comprehenders, n = 7), a reduction and delay of the N400 effect was obtained. In addition, the P300 component was measured in a classical oddball paradigm, in which subjects were asked to count infrequent low tones in a random series of high and low tones. No correlation was found between the occurrence of N400 and P300 effects, indicating that changes in the N400 results were related to the patients' language deficit. Overall, the pattern of results was compatible with the idea that aphasic patients with moderate to severe comprehension problems are impaired in the integration of lexical information into a higher order representation of the preceding sentence context.

Abstract

Although infants show remarkable sensitivity to linguistically relevant phonetic variation in speech, young children sometimes appear not to make use of this sensitivity. Here, children's knowledge of the sound-forms of familiar words was assessed using a visual fixation task. Dutch 19-month-olds were shown pairs of pictures and heard correct pronunciations and mispronunciations of familiar words naming one of the pictures. Mispronunciations were word-initial in Experiment 1 and word-medial in Experiment 2, and in both experiments involved substituting one segment with [d] (a common sound in Dutch) or [g] (a rare sound). In both experiments, word recognition performance was better for correct pronunciations than for mispronunciations involving either substituted consonant. These effects did not depend upon children's knowledge of lexical or nonlexical phonological neighbors of the tested words. The results indicate the encoding of phonetic detail in words at 19 months.

Abstract

This paper discusses the development of an orthography for the Touo language (Solomon Islands). Various orthographies have been proposed for this language in the past, and the paper discusses why they are perceived by the community to have failed. Current opinion about orthography development within the Touo-speaking community is divided along religious, political, and geographical grounds; and the development of a successful orthography must take into account a variety of opinions. The paper examines the social, historical, and linguistic obstacles that have hitherto prevented the development of an accepted Touo orthography, and presents a new proposal which has thus far gained acceptance with community leaders. The fundamental issue is that creating an orthography for a language takes place in a social, political, and historical context; and for an orthography to be acceptable for the speakers of a language, all these factors must be taken into account.

Abstract

The extent to which linguistic borrowing can be used to shed light on the existence and nature of early contact between Papuan and Oceanic speakers is examined. The question is addressed by taking one Papuan language, Lavukaleve, spoken in the Russell Islands, central Solomon Islands and examining lexical borrowings between it and nearby Oceanic languages, and with reconstructed forms of Proto Oceanic. Evidence from ethnography, culture history and archaeology, when added to the linguistic evidence provided in this study, indicates long-standing cultural links between other (non-Russell) islands. The composite picture is one of a high degree of cultural contact with little linguistic mixing, i.e., little or no changes affecting the structure of the languages and actually very little borrowed vocabulary.

Abstract

Repeated exposure to objects improves our ability to identify and name them, even after a long delay. Previous brain imaging studies have demonstrated that this experience-related facilitation of object naming is associated with neural changes in distinct brain regions. We used event-related functional magnetic resonance imaging (fMRI) to examine the modulation of neural activity in the object naming system as a function of experience and time. Pictures of common objects were presented repeatedly for naming at different time intervals (1 h, 6 h and 3 days) before scanning, or at 30 s intervals during scanning. The results revealed that as objects became more familiar with experience, activity in occipitotemporal and left inferior frontal regions decreased while activity in the left insula and basal ganglia increased. In posterior regions, reductions in activity as a result of multiple repetitions did not interact with time, whereas in left inferior frontal cortex larger decreases were observed when repetitions were spaced out over time. This differential modulation of activity in distinct brain regions provides support for the idea that long-lasting object priming is mediated by two neural mechanisms. The first mechanism may involve changes in object-specific representations in occipitotemporal cortices, the second may be a form of procedural learning involving a reorganization in brain circuitry that leads to more efficient name retrieval.

Abstract

In two ERP experiments, we assessed the impact of discourse-level information on the processing of an unfolding spoken sentence. Subjects listened to sentences like Jane told her brother that he was exceptionally quick/slow, designed such that the alternative critical words were equally acceptable within the local sentence context. In Experiment 1, these sentences were embedded in a discourse that rendered one of the critical words anomalous (e.g. because Jane’s brother had in fact done something very quickly). Relative to the coherent alternative, these discourse-anomalous words elicited a standard N400 effect that started at 150–200 ms after acoustic word onset. Furthermore, when the same sentences were heard in isolation in Experiment 2, the N400 effect disappeared. The results demonstrate that our listeners related the unfolding spoken words to the wider discourse extremely rapidly, after having heard the first two or three phonemes only, and in many cases well before the end of the word. In addition, the identical nature of discourse- and sentence-dependent N400 effects suggests that from the perspective of the word-elicited comprehension process indexed by the N400, the interpretive context delineated by a single unfolding sentence and a larger discourse is functionally identical.

Abstract

This Field Manual entry has been superceded by the published version: Van Staden, M., & Majid, A. (2006). Body colouring task. Language Sciences, 28(2-3), 158-161. doi:10.1016/j.langsci.2005.11.004.

Abstract

The temporal properties of semantic and phonological processes in speech production were investigated in a new experimental paradigm using movement-related brain potentials. The main experimental task was picture naming. In addition, a 2-choice reaction go/no-go procedure was included, involving a semantic and a phonological categorization of the picture name. Lateralized readiness potentials (LRPs) were derived to test whether semantic and phonological information activated motor processes at separate moments in time. An LRP was only observed on no-go trials when the semantic (not the phonological) decision determined the response hand. Varying the position of the critical phoneme in the picture name did not affect the onset of the LRP but rather influenced when the LRP began to differ on go and no-go trials and allowed the duration of phonological encoding of a word to be estimated. These results provide electrophysiological evidence for early semantic activation and later phonological encoding.

Abstract

This paper reports two experiments with vowels and consonants as phoneme detection targets in real words. In the first experiment, two relatively distinct vowels were compared with two confusible stop consonants. Response times to the vowels were longer than to the consonants. Response times correlated negatively with target phoneme length. In the second, two relatively distinct vowels were compared with their corresponding semivowels. This time, the vowels were detected faster than the semivowels. We conclude that response time differences between vowels and stop consonants in this task may reflect differences between phoneme categories in the variability of tokens, both in the acoustic realisation of targets and in the' representation of targets by subjects.

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

In two experiments, we explored the use of event-related brain potentials to selectively track the processes that establish reference during spoken language comprehension. Subjects listened to stories in which a particular noun phrase like "the girl" either uniquely referred to a single referent mentioned in the earlier discourse, or ambiguously referred to two equally suitable referents. Referentially ambiguous nouns ("the girl" with two girls introduced in the discourse context) elicited a frontally dominant and sustained negative shift in brain potentials, emerging within 300–400 ms after acoustic noun onset. The early onset of this effect reveals that reference to a discourse entity can be established very rapidly. Its morphology and distribution suggest that at least some of the processing consequences of referential ambiguity may involve an increased demand on memory resources. Furthermore, because this referentially induced ERP effect is very different from that of well-known ERP effects associated with the semantic (N400) and syntactic (e.g., P600/SPS) aspects of language comprehension, it suggests that ERPs can be used to selectively keep track of three major processes involved in the comprehension of an unfolding piece of discourse.

Abstract

An eye-movement reading experiment investigated whether the ease with which pronouns are processed is affected by the lexical frequency of their antecedent. Reading times following pronouns with infrequent antecedents were faster than following pronouns with frequent antecedents. We argue that this is consistent with a saliency account, according to which infrequent antecedents are more salient than frequent antecedents. The results are not predicted by accounts which claim that readers access all or part of the lexical properties of the antecedent during the processing of pronouns.

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

Pitch, intonation, and speech rate were analyzed in a collection of everyday speech heard by one Dutch infant between the ages of six and nine months. Components of each of these variables were measured in the speech of three adult speakers (mother, father, baby-sitter) when they addressed the infant, and when they addressed another adult. The results are in line with previously reported findings which are usually based on laboratory or prearranged settings: infant-directed speech in a natural setting exhibits more pitch variation, a larger number of simple intonation contours, and slower speech rate than does adult-directed speech.

Abstract

Dutch distinguishes at least four sentence types: statements and questions, the latter type being subdivided into wh-questions (beginning with a question word), yes/no-questions (with inversion of subject and finite), and declarative questions (lexico-syntactically identical to statement). Acoustically, each of these (sub)types was found to have clearly distinct global F0-patterns, as well as a characteristic distribution of final rises [1,2]. The present paper explores the separate contribution of parameters of global downtrend and size of accent-lending pitch movements versus aspects of the terminal rise to the human identification of the four sentence (sub)types, at various positions in the time-course of the utterance. The results show that interrogativity in Dutch can be identified at an early point in the utterance. However, wh-questions are not distinct from statements.

Abstract

Jescheniak and Levelt (Jescheniak, J.-D., Levelt, W.J.M. 1994. Journal of Experimental Psychology: Learning, Memory and Cognition 20 (4), 824–843) have suggested that the speed with which native speakers of a gender-marking language retrieve the grammatical gender of a noun from their mental lexicon may depend on the recency of earlier access to that same noun's gender, as the result of a mechanism that is dedicated to facilitate gender-marked anaphoric reference to recently introduced discourse entities. This hypothesis was tested in two picture naming experiments. Recent gender access did not facilitate the production of gender-marked adjective noun phrases (Experiment 1), nor that of gender-marked definite article noun phrases (Experiment 2), even though naming times for the latter utterances were sensitive to the gender of a written distractor word superimposed on the picture to be named. This last result replicates and extends earlier gender-specific picture-word interference results (Schriefers, H. 1993. Journal of Experimental Psychology: Learning, Memory, and Cognition 19 (4), 841–850), showing that one can selectively tap into the production of grammatical gender agreement during speaking. The findings are relevant to theories of speech production and the representation of grammatical gender for that process.

Abstract

Two experiments were carried out to explore the units of analysis is used by children to read Dutch bisyllabic pseudowords. Although Dutch orthography is highly regular, several deviations from a one-to-one correspondence occur. In polysyllabic words, the grapheme e may represent three different vowels:/∊/, /e/, or /λ/. In Experiment 1, Grade 6 elementary school children were presented lists of bisyllabic pseudowords containing the grapheme e in the initial syllable representing a content morpheme, a prefix, or a random string. On the basis of general word frequency data, we expected the interpretation of the initial syllable as a random string to elicit the pronunciation of a stressed /e/, the interpretation of the initial syllable as a content morpheme to elicit the pronunciation of a stressed /∊/, the interpretation of the initial syllable as a content morpheme to elicit the pronunciation of a stressed /∊/, and the interpretation as a prefix to elicit the pronunciation of an unstressed /&lamda;/. We found both the pronunciation and the stress assignment for pseudowords to depend on word type, which shows morpheme boundaries and prefixes to be identified. However, the identification of prefixes could also be explained by the correspondence of the prefix boundaries in the pseudowords to syllable boundaries. To exclude this alternative explanation, a follow-up experiment with the same group of children was conducted using bisyllabic pseudowords containing prefixes that did not coincide with syllable boundaries versus similar pseudowords with no prefix. The results of the first experiment were replicated. That is, the children identified prefixes and shifted their assignment of word stress accordingly. The results are discussed with reference to a parallel dual-route model of word decoding

Abstract

A common way for researchers to model or graphically portray spatial knowledge of a large environment is by applying multidimensional scaling (MDS) to a set of pairwise distance estimations. We introduce two MDS-like techniques that incorporate people’s knowledge of directions instead of (or in addition to) their knowledge of distances. Maps of a familiar environment derived from these procedures were more accurate and were rated by participants as being more accurate than those derived from nonmetric MDS. By incorporating people’s relatively accurate knowledge of directions, these methods offer spatial cognition researchers and behavioral geographers a sharper analytical tool than MDS for studying cognitive maps.