Presentations

Abstract

Individual differences in language processing are prevalent in our daily lives. However, for decades, psycholinguistic research has largely ignored variation in the normal range of abilities. Recently, scientists have begun to acknowledge the importance of inter-individual variability for a comprehensive characterization of the language system. In spite of this change of attitude, empirical research on individual differences is still sparse, which is in part due to the lack of a suitable research tool. Here, we present a novel battery of behavioral tests for assessing individual differences in language skills in younger adults. The Dutch prototype comprises 29 subtests and assesses many aspects of language knowledge (grammar and vocabulary), linguistic processing skills (word and sentence level) and general cognitive abilities involved in using language (e.g., WM, IQ). Using the battery, researchers can determine performance profiles for individuals and link them to neurobiological or genetic data.

Abstract

It is evident that speakers can freely vary stylistic features of their speech, such as speech rate, but how they accomplish this has hardly been studied, let alone implemented in a formal model of speech production. Much as in walking and running, where qualitatively different gaits are required cover the gamut of different speeds, we might predict there to be multiple qualitatively distinct configurations, or ‘gaits’, in the speech planning system that speakers must switch between to alter their speaking rate or style. Alternatively, control might involve continuous modulation of a single ‘gait’. We investigate these possibilities by simulation of a connectionist computational model which mimics the temporal characteristics of observed speech. Different ‘regimes’ (combinations of parameter settings) can be engaged to achieve different speaking rates.

The model was trained separately for each speaking rate, by an evolutionary optimisation algorithm. The training identified parameter values that resulted in the model to best approximate syllable duration distributions characteristic of each speaking rate.

In one gait system, the regimes used to achieve fast and slow speech are qualitatively similar, but quantitatively different. In parameter space, they would be arranged along a straight line. Different points along this axis correspond to different speaking rates. In a multiple gait system, this linearity would be missing. Instead, the arrangement of the regimes would be triangular, with no obvious relationship between the regions associated with each gait, and an abrupt shift in parameter values to move from speeds associated with ‘walk-speaking’ to ‘run-speaking’.

Our model achieved good fits in all three speaking rates. In parameter space, the arrangement of the parameter settings selected for the different speaking rates is non-axial, suggesting that ‘gaits’ are present in the speech planning system.

Abstract

It is unknown whether modality affects the efficiency with which we learn novel word forms and their meanings. In this study, 60 participants were trained on 24 pseudowords, each paired with a pictorial meaning (novel object). Following a 20 minute filler task participants were tested on their ability to identify the picture-word form pairs on which they were trained when presented amongst foils. Word forms were presented in either their written or spoken form, with exposure to the written form equal to the speech duration of the spoken form. The between subjects design generated four participant groups 1) written training, written test; 2) written training, spoken test; 3) spoken training, written test; 4) spoken training, spoken test. Our results show a written training advantage: participants trained on written words were more accurate on the matching task. An ongoing follow-up experiment tests whether the written advantage is caused by additional time with the full word form, given that words can be read faster than the time taken for the spoken form to unfold. To test this, in training, written words were presented with sufficient time for participants to read, yet maximally half the duration of the spoken form in experiment 1.

Abstract

It is unknown whether modality affects the efficiency with which humans learn novel word forms and their meanings, with previous studies reporting both written and auditory advantages. The current study implements controls whose absence in previous work likely offers explanation for such contradictory findings. In two novel word learning experiments, participants were trained and tested on pseudoword - novel object pairs, with controls on: modality of test, modality of meaning, duration of exposure and transparency of word form. In both experiments word forms were presented in either their written or spoken form, each paired with a pictorial meaning (novel object). Following a 20-minute filler task, participants were tested on their ability to identify the picture-word form pairs on which they were trained. A between subjects design generated four participant groups per experiment 1) written training, written test; 2) written training, spoken test; 3) spoken training, written test; 4) spoken training, spoken test. In Experiment 1 the written stimulus was presented for a time period equal to the duration of the spoken form. Results showed that when the duration of exposure was equal, participants displayed a written training benefit. Given words can be read faster than the time taken for the spoken form to unfold, in Experiment 2 the written form was presented for 300 ms, sufficient time to read the word yet 65% shorter than the duration of the spoken form. No modality effect was observed under these conditions, when exposure to the word form was equivalent. These results demonstrate, at least for proficient readers, that when exposure to the word form is controlled across modalities the efficiency with which word form-meaning associations are learnt does not differ. Our results therefore suggest that, although we typically begin as aural-only word learners, we ultimately converge on developing learning mechanisms that learn equally efficiently from both written and spoken materials.

Abstract

It is unknown whether modality affects the efficiency with which humans learn novel word forms and their meanings, with previous studies reporting both written and auditory advantages. The current study implements controls whose absence in previous work likely offers explanation for such contradictory findings. In two novel word learning experiments, participants were trained and tested on pseudoword - novel object pairs, with controls on: modality of test, modality of meaning, duration of exposure and transparency of word form. In both experiments word forms were presented in either their written or spoken form, each paired with a pictorial meaning (novel object). Following a 20-minute filler task, participants were tested on their ability to identify the picture-word form pairs on which they were trained. A between subjects design generated four participant groups per experiment 1) written training, written test; 2) written training, spoken test; 3) spoken training, written test; 4) spoken training, spoken test. In Experiment 1 the written stimulus was presented for a time period equal to the duration of the spoken form. Results showed that when the duration of exposure was equal, participants displayed a written training benefit. Given words can be read faster than the time taken for the spoken form to unfold, in Experiment 2 the written form was presented for 300 ms, sufficient time to read the word yet 65% shorter than the duration of the spoken form. No modality effect was observed under these conditions, when exposure to the word form was equivalent. These results demonstrate, at least for proficient readers, that when exposure to the word form is controlled across modalities the efficiency with which word form-meaning associations are learnt does not differ. Our results therefore suggest that, although we typically begin as aural-only word learners, we ultimately converge on developing learning mechanisms that learn equally efficiently from both written and spoken materials.

Abstract

Studies on the generation effect have found that coming up with words, compared to reading them, improves memory. However, because these studies used words at both study and test, it is unclear whether generation affects visual or conceptual/lexical representations. Here, participants named pictures after hearing the picture name (no-generation condition), backward speech, or an unrelated word (easy and harder generation conditions). We ruled out effects at the visual level by testing participants’ recognition memory on the written names of the pictures that were named earlier. We also assessed the effect of processing time during generation on memory. In the recognition memory test, participants were more accurate in the generation conditions than in the no-generation condition. They were also more accurate for words that took longer to be retrieved, but only when generation was required. This work shows that generation affects conceptual/lexical representations and informs the relationship between language and memory.

Abstract

If message and sentence planning are closely linked processes, planning scope may vary depending on what speakers want to say and how they say it. We compared speakers’ gaze pattern to pictures in displays eliciting sentences like “The lion and the tiger are above the basket” when speakers were a) more familiar or less familiar with the spatial layout of these displays, and b) more familiar or less familiar with the phrasal structures used in these sentences. Familiarity with spatial layout was induced by presenting prime trials with a similar or dissimilar layout of pictures (“The bell and the nail are above/below the crutch”) before the target trial, and familiarity with sentence structure was manipulated via structural priming (prime trials elicited sentences like “The bell and the nail are above the crutch” or “The bell is above the nail and the crutch”). When describing pictures on target trials, speakers looked earlier at the second object (tiger) when they were familiar with both the spatial layout and sentence structure, but speech onsets were reduced (structural priming) only when both spatial layout and sentence structure were repeated. The results show that linguistic planning is facilitated by congruence between message-level and sentence-level structure.

Abstract

Studies of lexical access in speech planning often use priming or interference paradigms, where a target picture is combined with a written prime or distracter word. A difficulty in interpreting the results of studies using interference paradigms with clearly visible distracters is that effects arising during lexical access cannot be distinguished from effects arising during self-monitoring. A difficulty with using masked priming paradigms is that the effects tend to be small and fragile. We report a series of picture naming experiments using both the conventional masked priming procedure and the sandwich priming procedure first used in lexical decision experiments by Lupker and masked prime the participants are briefly (i.e., 33 ms) presented the name of the target picture. Although neither categorically nor phonologically related primes significantly affected picture naming in the traditional masked priming experiments, in the sandwich priming experiments: (a) categorically related primes (e.g. “dog-cat”) interfered more than unrelated distracters with picture naming and (b) phonologically related primes (“mat-cat”) facilitated picture naming. The theoretical implications of these findings will be discussed. Lupker, S.J., & Davis, C.J. (2009). Sandwich priming: A method for overcoming the limitations of masked priming by reducing lexical competition effects. Journal of Experimental Psychology: Learning, Memory, & Cognition, 35, 618-639.

Abstract

Models of the mental representation of morphologically complex words traditionally fall into one of two categories, Single-Route or Dual-Route models. The former further distinguish between Full-Listing (e.g. Butterworth, 1983) and Decomposition (e.g. Taft & Forster, 1976), while the latter assume different systems governing the access of mono- vs. polymorphemic words (e.g. Pinker & Prince, 1994; Pinker & Ullman, 2002). One of the main arguments against decomposition and continuous online computations is the cognitive resources this process would require. Turning this reasoning around, taxing someone's working memory capacities should then uniquely affect the computation of bimorphemic verb forms. We tested this hypothesis on 48 Dutch native speakers with a lexical decision task, comparing reaction times for Dutch regular past tense forms to frequency-matched irregular past tense forms, both under low and under high cognitive load. We found that frequency influenced reactions to monomorphemic but not to bimorphemic forms (F(1, 47) = 4.734, p = .035), favoring a listing account for the former but a computational procedure for the latter forms. This interaction, however, was present only for a certain group of people (F(1, 23) = 6.279, p = .02), namely those whose reaction times were hardly affected by the load manipulation and who thus may be thought of as having larger working memory capacities. On the other hand, participants who showed a strong load effect had no interaction between number of morphemes and frequency (F(1, 23) = .575, ns), indicating that they process monomorphemic and bimorphemic forms in a similar manner. It seems that cognitive capacities influence the storage of and access to polymorphemic verb forms. While people with greater working memory skills use these resources to compute morphologically complex inflections on-line, people with smaller cognitive capacities seem to rely on a list-like storage for bimorphemic forms as well.

Abstract

Speakers clearly differ in how quickly they can retrieve words from the mental lexicon, but little is known about the sources of this variability. The present study investigated the relationship between speakers’ executive control abilities and their speed of picture naming. In two experiments, adult speakers of British English named line drawings of objects and actions. Three main components of executive control - updating, shifting of attention, and inhibiting - were assessed using the operation-span, number-letter shifting, and stop-signal task, respectively (see Myake et al.,2000 ). Reaction times (RT) to action and object pictures were highly correlated. Ex-Gaussian analyses of the RT distributions showed that the speakers’ updating scores correlated with the tau parameter of the RT distributions, i.e. predicted the proportions of slow responses in action and object naming. The inhibiting scores correlated with the mean RTs, whereas the scores obtained in the number-letter shifting task were uncorrelated to the RTs. These results indicate that the executive control abilities of updating and inhibiting contribute to the speed of naming objects and actions. Theories of word production may require modification to take account of these findings.

Abstract

a bitter rain – two silences beneath the one umbrella Is the connotative meaning of texts readily available or is it gleaned at an extra cognitive cost? The eye-movements of 31 English native speakers (10 male, mean age 21 years) were recorded while reading 24 haiku, 12 in the original/symbolic version, and 12 in a modified version where the most symbolic word (the keyword ‘bitter’ in the example) was replaced by a more literal word (‘loud’) reducing the text’s symbolic purport. The effects of keyword substitutions were measured globally, comparing total reading times for the two haiku types, and locally, examining the first pass gaze durations and dwell times on a word closely connected to the keyword, the referent ‘silences’, and on the last word, ‘umbrella’, to examine wrap-up processes. First pass duration showed no effects of the substitution. However, dwell time on referents and last-word regions, and total reading time were significantly longer for the original than for the altered haiku, suggesting that the connotative meaning of the texts was not available immediately but only through re-reading of the texts. The implications of these findings are discussed in relation to the literature on the processing of inferences in symbolic texts.

Abstract

a bitter rain – two silences beneath the one umbrella Is the connotative meaning of a text readily available or is it accessed only after re-examining a text? Thirtyone English native speakers (10 male, mean age 21) read 24 haiku, 12 in their original/symbolic version and 12 in a version in which the most symbolic word (the keyword "bitter" in the example above) was replaced by a more literal word ("loud"), reducing the text’s symbolic purport. Participants' eye movements were recorded using the eye-tracker EyeLink 1000. The effect of the word substitution was measured globally, by comparing the total reading times for the two haiku types, and locally, by examining first pass duration and dwell time on a word closely connected to the keyword (the referent, "silences") and on the last word ("umbrella"), as this might show wrap-up processes. First pass durations showed no effects of the substitution. However, total reading time and dwell time on both the referent and the last-word regions were significantly longer for haiku with the original keyword than for haiku with the altered keyword. These findings suggest that the texts’ connotative meaning was not available immediately but only through re-reading of the texts.

Abstract

When children learn their native language, they have to deal with a confusing array of dependencies between various elements in an utterance. Some of these dependencies may be adjacent to one another whereas others can be separated by considerable intervening material. In this study, we investigate whether both types of dependencies can be learned together, similarly to the task facing young children. Statistical learning of adjacent dependencies (probability = .17) and non-adjacent dependencies (probability = 1.0) was assessed in two experiments using a modified serial-reaction-time task. The results showed (i) increasing online sensitivity to both dependency types during training, (ii) better nonadjacency than adjacency learning, and (iii) nonadjacency learning being highly correlated with adjacency learning, suggesting that adjacency and non-adjacency learning can occur in parallel and might be subserved by a common statistical learning mechanism. An overnight break between two training sessions helped the online learning performance of slower learners to approach that of faster learners, but the same amount of training without such a break (a 15-min interval) did not, suggesting that memory consolidation may play a role in statistical learning of complex statistical patterns, especially for slower learners.