Presentations

Abstract

Serial naming deficits have been identified as core symptoms of developmental dyslexia. A prominent hypothesis is that naming delays are due to inefficient phonological encoding, yet the exact nature of this underlying impairment remains largely underspecified. Here we used recordings of eye movements and word onset latencies to examine at what processing level the dyslexic naming deficit emerges: localized at an early stage of lexical encoding or rather later at the level of phonetic or motor planning. 23 dyslexic and 25 control adult readers were tested on a serial object naming task for 30 items and an analogous reading task, where phonological neighborhood density and word-frequency were manipulated. Results showed that both word properties influenced early stages of phonological activation (first fixation and first-pass duration) equally in both groups of participants. Moreover, in the control group any difficulty appeared to be resolved early in the reading process, while for dyslexic readers a processing disadvantage for low-frequency words and for words with sparse neighborhood also emerged in a measure that included late stages of output planning (eye-voice span). Thus, our findings suggest suboptimal phonetic and/or articulatory planning in dyslexia.

Abstract

Speech segmentation requires flexible mechanisms to remain robust to features such as speech rate and pronunciation. Recent hypotheses suggest that low-frequency neural oscillations entrain to ongoing syllabic and phrasal rates, and that neural entrainment provides a speech-rate invariant means to discretize linguistic tokens from the acoustic signal. How this mechanism functionally operates remains unclear. Here, we test the hypothesis that neural entrainment reflects temporal predictive mechanisms. It implies that neural entrainment is built on the dynamics of past speech information: the brain would internalize the rhythm of preceding speech to parse the ongoing acoustic signal at optimal time points. A direct prediction is that ongoing neural oscillatory activity should match the rate of preceding speech even if the stimulation changes, for instance when the speech rate suddenly increases or decreases. Crucially, the persistence of neural entrainment to past speech rate should modulate speech perception. We performed an MEG experiment in which native Dutch speakers listened to sentences with varying speech rates. The beginning of the sentence (carrier window) was either presented at a fast or a slow speech rate, while the last three words (target window) were displayed at an intermediate rate across trials. Participants had to report the perception of the last word of the sentence, which was ambiguous with regards to its vowel duration (short vowel /ɑ/ – long vowel /aː/ contrast). MEG data was analyzed in source space using beamformer methods. Consistent with previous behavioral reports, the perception of the ambiguous target word was influenced by the past speech rate; participants reported more /aː/ percepts after a fast speech rate, and more /ɑ/ after a slow speech rate. During the carrier window, neural oscillations efficiently tracked the dynamics of the speech envelope. During the target window, we observed oscillatory activity that corresponded in frequency to the preceding speech rate. Traces of neural entrainment to the past speech rate were significantly observed in medial prefrontal areas. Right superior temporal cortex also showed persisting oscillatory activity which correlated with the observed perceptual biases: participants whose perception was more influenced by the manipulation in speech rate also showed stronger remaining neural oscillatory patterns. The results show that neural entrainment lasts after rhythmic stimulation. The findings further provide empirical support for oscillatory models of speech processing, suggesting that neural oscillations actively encode temporal predictions for speech comprehension.

Abstract

Previous research indicates that general cognitive abilities, such as attention or executive control, contribute to language processing (Hartsuiker & Barkhuysen, 2006; Jongman et al., 2014; Shao et al., 2013). Potential effects of language-specific abilities, such as vocabulary, on language processing in adult native speakers have been examined less extensively. Goals: a) develop and assess measures of vocabulary size in Dutch native speakers, and b) investigate the relationship between individual differences in vocabulary and language processing.

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. It has been suggested that this process of speech rate normalization occurs across talker changes. This would predict that the speech rate of talker A influences perception of the rate of another talker B. We assessed this hypothesis by testing effects of speech rate on the perception on the Dutch vowel continuum /A/-/a:/. One participant group was exposed to 'neutral' speech from talker A intermixed with fast speech from talker B. Another group listened to the same speech from talker A, but to slow speech from talker B. We observed a difference in perception of talker A depending on the speech rate of talker B: A's 'neutral' speech was perceived as slow when B spoke faster. These findings corroborate the idea that speech rate normalization occurs across talkers, but they challenge the assumption that listeners average over speech rates from multiple talkers. Instead, they suggest that listeners contrast talker-specific rates.

Abstract

Natural conversations are characterized by smooth transitions of turns between interlocutors. For instance, speakers often respond to questions or requests within half a second. As planning the first word of an utterance can easily take a second or more, this suggests that utterance planning often overlaps with listening to the preceding speaker's utterance. A specific proposal concerning the temporal coordination of listening and speech planning has recently been made by Levinson and Torreira (2016, Frontiers in Psychology; Levinson, 2016, Trends in Cognitive Sciences). They propose that speakers initiate their speech planning as soon as they have understood the speech act and gist of the preceding utterance. However, direct evidence for simultaneous listening and speech planning is scarce. I will first review studies demonstrating that both comprehending spoken utterances and planning them require processing capacity and that these processes can substantially interfere with each other. These data suggest that concurrent speech planning and listening should be cognitively quite challenging. In the second part of the talk I will turn to studies examining directly when utterance planning in dialogue begins. These studies indicate that (regrettably) there are probably no hard-and-fast rules for the temporal coordination of listening and speech planning. I will argue that (regrettably again) we need models that are far more complex than Levinson and Torreira's proposal to understand how listening and speech planning are coordinated in conversation

Abstract

We show that language users readily learn the probabilities of novel lexical cues to syntactic information (verbs biasing towards a prepositional object dative vs. double-object dative and words biasing towards a verb vs. noun reading) and use these biases in a subsequent production task. In a one-hour exposure phase participants read 12 novel lexical items, embedded in 30 sentence contexts each, in their native language. The items were either strongly (100%) biased towards one grammatical frame or syntactic category assignment or unbiased (50%). The next day participants produced sentences with the newly learned lexical items. They were given the sentence beginning up to the novel lexical item. Their output showed that they were highly sensitive to the biases introduced in the exposure phase.
Given this rapid learning and use of novel lexical cues, this paradigm opens up new avenues to test sentence processing theories. Thus, with close control on the biases participants are acquiring, competition between different frames or category assignments can be investigated using reaction times or neuroimaging methods.
Generally, these results show that language users adapt to the statistics of the linguistic input, even to subtle lexically-driven cues to syntactic information.

Abstract

The name-picture verification task is often used to assess the difficulty of prelexical processes (object recognition and semantic access) during picture naming. However, whether to use responses from word-picture match or from mismatch trials to index the difficulty of pre-lexical processes is debated. Levelt (2002) argued for the use of mismatch trials because on match trials the printed object name might facilitate picture recognition. However, in a study with speakers of Spanish Stadthagen-Gonzalez et al. (2009) showed that visual and conceptual properties of objects only correlated with the latencies of match responses but not with those of mismatch responses and therefore advocated the use of match responses. The present study aimed to replicate Stadthagen- Gonzalez et al. (2009) findings using native British English speakers and English norms for non-lexical and lexical variables. We replicated the finding that non-lexical variables affected the speed of match, but not mismatch responses. However, in addition, we found that lexical variables also affected the speed of match responses, which means that these latencies need to be interpreted with caution. In other words, neither match nor mismatch responses seem ideally suited to assess the difficulty of pre-lexical processes in picture naming. Levelt, W. J. M. (2002). Picture naming and word frequency. Language and Cognitive Processes, 17, 663–671. Stadthagen-Gonzalez, H., Damian, M. F., Pérez, M. A., Bowers, J. S., & Marín, J. (2009). Name-picture verification as a control measure for object naming: A task analysis and norms for a

Abstract

As the popularity of sending messages electronically increased, so did the necessity of conveying messages more efficiently. A popular way of increasing efficiency is to use shortcuts such as gr8 “great” or cu “see you”. The aim of the study was to investigate whether such abbreviations have their own lexical representations or whether they are recorded into the words they stand for. We used associative masked and overt priming in lexical decision tasks. Primes were text shortcuts and their corresponding words. Targets were words that were associatively related to the prime (e.g., cu/see you – GOODBYE), associatively related to a part of the prime (e.g., cu/see you – LOOK) or unrelated to the prime and any part of the prime (e.g., 4u/for you – GOODBYE; 4u/for you – LOOK). In both tasks, responses were faster to targets preceded by related compared to unrelated primes (shortcuts and words). In the overt priming task, we in addition found faster responses when the target was related to a part of the prime. However, this effect was present only for word but not for shortcut primes. These results indicate that shortcuts have their own lexical representations that are independent of the representations of the individual words they replace.

Abstract

Ik laat zien dat het gebruik van sms- en msn-afkortingen geen schadelijke gevolgen heeft op het begrip van geschreven taal zoals blijkt uit een reeks van experimenten. Sterker nog, afkortingen hebben een eigen representatie in ons mentale woordenboek (bijvoorbeeld ‘iig’) en worden niet vertaald naar woorden waaruit ze bestaan (bijvoorbeeld ‘in ieder geval’). Het gebruik van korte tekstberichten via mobiele telefoons en e-mail neemt steeds meer toe en daardoor worden steeds meer afkortingen en acroniemen in de taal gebruikt. Momenteel worden er wereldwijd naar schatting 2000 miljard sms-jes per jaar verstuurd. In Nederland en België sms’t ongeveer 80% van de jongeren regelmatig, en ongeveer 70% van hen gebruikt sms-taal (Daniels, 2009). Het gebruik van afkortingen heeft de schuld gekregen van de verloedering van de Nederlandse taal, iets dat men terug zou zien in de kwaliteit van het Nederlands in e-mails en brieven. Verder gebruik van afkortingen zou de communicatie verslechteren tussen de gebruikers van afkortingen en niet gebruikers, bijvoorbeeld tussen studenten en docenten. De vraag is of dat echt zo is. Uit mijn onderzoek blijkt dat het begrijpen van een tekst niet leidt onder het gebruik van afkortingen in de zinnen

Abstract

Earlier research has shown that speakers naming object pairs can retrieve their names in parallel, but often fail to do so. The conditions for the occurrence of parallel object processing are largely unknown. We examined how associations between objects affected the speakers’ processing strategies. In Experiment 1, participants named object triplets in a left-right-bottom order. During the saccade towards the right object (interloper), it was replaced by a new object (target). We varied the relationship between interloper and target (conceptually related or unrelated) and between interloper and left object (categorically related, associated, unrelated). Target gaze durations were shorter after related than unrelated interlopers. However, this preview effect was independent of the interloper-left object relationship, suggesting that the left and right object were processed sequentially. In Experiments 2 and 3, participants named pairs of associated or unrelated objects. The left objects were repeated several times in each test block to facilitate their processing. Gaze durations for the left objects were longer in associated than unrelated pairs, consistent with parallel processing of the associated objects and interference among them. We will discuss how the difficulty of processing the objects and the relationship between them jointly determine speakers’ processing strategy.

Abstract

Individuals differ greatly on how efficiently they can retrieve words from the mental lexicon in spoken word production. Little is known about how this individual difference might be related to individual difference in other cognitive abilities. The present study investigated the relationship between individuals’ working memory capacity and their efficiency of lexical access. Speeded naming of drawings of actions and objects was used to measure the efficiency of lexical access. To assess working memory capacity, we used the Operation Span (OSPAN) task (Turner & Engle, 1989), in which participants memorize unrelated words while making judgments on simple mathematic operations. We found that action naming response time (RT) was significantly longer than object naming RT. More importantly, there was a significant negative correlation between the action naming RT and the OSPAN score. There was no correlation between object naming RT and the OSPAN score. Ex-Gaussian analyses of the RT distributions revealed that the negative relationship between OSPAN and RT was evident throughout the distributions (i.e., reflected in the Gaussian part of the distribution). These results suggest that when words are difficult to select (our verbcondition) people with larger working memory capacity outperform people with lower working memory capacity. Turner, M. L., & Engle. R. W. (1989). Is working memory capacity task dependent? Journal of Memory and Language, 28, 127-154.