Presentations

Abstract

Conversation often involves simultaneous production and comprehension, yet little research has investigated whether these two processes interfere with one another. We tested participants’ ability to dual-task with production and comprehension tasks. Task one (production task) was picture naming. Task two (comprehension task) was either syllable identification (linguistic condition) or tone identification (non-linguistic condition). The two identification tasks were matched for difficulty. Three SOAs (50ms, 300ms, and 1800ms) resulted in different amounts of overlap between the production and comprehension tasks. We hypothesized that as production and comprehension use similar resources there would be greater interference with concurrent linguistic than non-linguistic tasks.
At the 50ms SOA, picture naming latencies were slower in the linguistic compared to the non-linguistic condition, suggesting that the resources required for production and comprehension overlap more in the linguistic condition. As the syllables were non-words without lexical representations, this interference likely occurs primarily at the phonological level. Across all SOAs, identification RTs were longer in the linguistic condition, showing that such phonological interference percolates through to the comprehension task, regardless of SOA. In sum, these results demonstrate that concurrent access to the phonological level in production and comprehension results in measurable interference in both speaking and comprehending.

Abstract

Listeners are continuously exposed to a broad range of speech rates. Earlier work has shown that listeners perceive phonetic category boundaries relative to contextual speech rate. This process of rate-dependent speech perception has been suggested to occur across talker changes, with the speech rate of talker A influencing perception of talker B. This study tested whether a ‘global’ speech rate calculated over multiple talkers and over a longer period of time affected perception of the temporal Dutch vowel contrast /ɑ/-/a:/. First, Experiment 1 demonstrated that listeners more often reported hearing long /a:/ in fast contexts than in ‘neutral rate’ contexts, replicating earlier findings. Then, in Experiment 2, one participant group was exposed to ‘neutral’ speech from talker A intermixed with slow speech from talker B. Another group listened to the same ‘neutral’ speech from talker A, but to fast speech from talker B. Between-group comparison in the ‘neutral’ condition revealed that Group 1 reported more long /a:/ than Group 2, indicating that A’s ‘neutral’ speech sounded faster when B was slower. Finally, Experiment 3 tested whether talking at slow or fast rates oneself elicits the same ‘global’ rate effects. However, no evidence was found that self-produced speech modulated perception of talker A. This study corroborates the idea that ‘global’ rate-dependent effects occur across talkers, but are insensitive to one’s own speech rate. Results are interpreted in light of the general auditory mechanisms thought to underlie rate normalization, with implications for our understanding of dialogue.

Abstract

Speech rate is known to modulate perception of temporally ambiguous speech sounds. For instance, a vowel may be perceived as short when the immediate speech context is slow, but as long when the context is fast. Yet, effects of long-term tracking of speech rate are largely unexplored. Two experiments tested whether long-term tracking of rate influences perception of the temporal Dutch vowel contrast /A/-/a:/. In Experiment 1, one low-rate group listened to ‘neutral’ rate speech from talker A and to slow speech from talker B. Another high-rate group was exposed to the same neutral speech from A, but to fast speech from B. Between-group comparison of the ‘neutral’ trials revealed that the low-rate group reported a higher proportion of /a:/ in A’s ‘neutral’ speech, indicating that A sounded faster when B was slow. Experiment 2 tested whether one’s own speech rate also contributes to effects of long-term tracking of rate. Here, talker B’s speech was replaced by playback of participants’ own fast or slow speech. No evidence was found that one’s own voice affected perception of talker A in larger speech contexts. These results carry implications for our understanding of the mechanisms involved in rate-dependent speech perception and of dialogue.

Abstract

Speech rate is known to modulate perception of temporally ambiguous speech sounds. For instance, a vowel may be perceived as short when the immediate speech context is slow, but as long when the context is fast. Yet, effects of long-term tracking of speech rate are largely unexplored. Two experiments tested whether long-term tracking of rate influences perception of the temporal Dutch vowel contrast /ɑ/-/a:/. In Experiment 1, one low-rate group listened to 'neutral' rate speech from talker A and to slow speech from talker B. Another high-rate group was exposed to the same neutral speech from A, but to fast speech from B. Between-group comparison of the 'neutral' trials revealed that the low-rate group reported a higher proportion of /a:/ in A's 'neutral' speech, indicating that A sounded faster when B was slow. Experiment 2 tested whether one's own speech rate also contributes to effects of long-term tracking of rate. Here, talker B's speech was replaced by playback of participants' own fast or slow speech. No evidence was found that one's own voice affected perception of talker A in larger speech contexts. These results carry implications for our understanding of the mechanisms involved in rate-dependent speech perception and of dialogue.

Abstract

Speech can be produced at different rates. The ability to produce faster or slower speech may be thought to result from executive control processes enlisted to modulate lexical selection and phonological encoding stages of speech planning.

This study used simulations of the model of serial order in language by Dell, Burger and Svec (1997, DBS) to characterise the strategies adopted by speakers when naming pictures at fast, medium and slow prescribed rates. Our new implementation of DBS was able to produce activation patterns that correlated strongly with observed syllable-level timing of disyllabic words from this task.

For each participant, different speaking rates were associated with different regions of the DBS parameter space. The precise placement of the speaking rates in the parameter space differed markedly between participants. Participants applied broadly the same parameter manipulation to accelerate their speech. This was however not the case for deceleration. Hierarchical clustering revealed two distinct patterns of parameter adjustment employed to decelerate speech, suggesting that deceleration is not necessarily achieved by the inverse process of acceleration. In addition, potential refinements to the DBS model are discussed.

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.