Presentations

Abstract

Prominent theories of predictive language processing assume that language production processes are used to anticipate upcoming linguistic input during comprehension (Dell & Chang, 2014; Pickering & Garrod, 2013). Here, we explored the converse case: Does a task set including production in addition to comprehension encourage prediction, compared to a task only including comprehension? To test this hypothesis, participants carried out a cross-modal naming task (Exp 1a), a self-paced reading task (Exp1 b) that did not include overt production, and a task (Exp 1c) in which naming and reading trials were evenly interleaved. We used the same predictable (N = 40) and non-predictable (N = 40) sentences in all three tasks. The sentences consisted of a fixed agent, a transitive verb and a predictable or non-predictable target word (The man breaks a glass vs. The man borrows a glass). The mean cloze probability in the predictable sentences was .39 (ranging from .06 to .8; zero in the non-predictable sentences). A total of 162 volunteers took part in the experiment which was run in a between-participants design. In Exp 1a, fifty-four participants listened to recordings of the sentences which ended right before the spoken target word. Coinciding with the end of the playback, a picture of the target word was shown which the participants were asked to name as fast as possible. Analyses of their naming latencies revealed a statistically significant naming advantage of 108 ms on predictable over non-predictable trials. Moreover, we found that the objects’ naming advantage was predicted by the target words’ cloze probability in the sentences (r = .347, p = .038). In Exp 1b, 54 participants were asked to read the same sentences in a self-paced fashion. To allow for testing of potential spillover effects, we added a neutral prepositional phrase (breaks a glass from the collection/borrows a glass from the neighbor) to each sentence. The sentences were read word-by-word, advancing by pushing the space bar. On 30% of the trials, comprehension questions were used to keep up participants' focus on comprehending the sentences. Analyses of their spillover region reading times revealed a numerical advantage (8 ms; tspillover = -1.1, n.s.) in the predictable as compared to the non-predictable condition. Importantly, the analysis of participants' responses to the comprehension questions, showed that they understood the sentences (mean accuracy = 93%). In Exp 1c, the task comprised 50% naming trials and 50% reading trials which appeared in random order. Fifty-four participants named and read the same objects and sentences as in the previous versions. The results showed a naming advantage on predictable over non-predictable items (99 ms) and a positive correlation between the items’ cloze probability and their naming advantage (r = .322, p = .055). Crucially, the post-target reading time analysis showed that with naming trials and reading trials interleaved, there was also a statistically reliable prediction effect on reading trials. Participants were 19 ms faster at reading the spillover region on predictable relative to non-predictable items (tspillover = -2.624). To summarize, although we used the same sentences in all sub-experiments, we observed effects of prediction only when the task set involved production. In the reading only experiment (Exp 1b), no evidence for anticipation was obtained although participants clearly understood the sentences and the same sentences yielded reading facilitation when interleaved with naming trials (Exp 1c). This suggests that predictive language processing can be modulated by the comprehenders’ task set. When the task set involves language production, as is often the case in natural conversation, comprehenders appear to engage in prediction to a stronger degree than in pure comprehension tasks. In our discussion, we will discuss the notion that language production may engage prediction, because being able to predict words another person is about to say might optimize the comprehension process and enable smooth turn-taking.

Abstract

A substantial body of literature has shown that readers and listeners often anticipate information. An open question concerns the mechanisms underlying predictive language processing. Multiple mechanisms have been suggested. One proposal is that comprehenders use event knowledge to predict upcoming words. Other theoretical frameworks propose that predictions are made based on simple word associations. In a recent EEG study, Metusalem and colleagues reported evidence for the modulating influence of event knowledge on prediction. They examined the degree to which event knowledge is activated during sentence comprehension. Their participants read two sentences, establishing an event scenario, which were followed by a final sentence containing one of three target words: a highly expected word, a semantically unexpected word that was related to the described event, or a semantically unexpected and event-unrelated word (see Figure, for an example). Analyses of participants’ ERPs elicited by the target words revealed a three-way split with regard to the amplitude of the N400 elicited by the different types of target: the expected targets elicited the smallest N400, the unexpected and event-unrelated targets elicited the largest N400. Importantly, the amplitude of the N400 elicited by the unexpected but event-related targets was significantly attenuated relative to the amplitude of the N400 elicited by the unexpected and event-unrelated targets. Metusalem et al. concluded that event knowledge is immediately available to constrain on-line language processing. Based on a post-hoc analysis, the authors rejected the possibility that the results could be explained by simple word associations. In the present study, we addressed the role of simple word associations in discourse comprehension more directly. Specifically, we explored the contribution of associative priming to the graded N400 pattern seen in Metusalem et al’s study. We conducted two EEG experiments. In Experiment 1, we reran Metusalem and colleagues’ context manipulation and closely replicated their results. In Experiment 2, we selected two words from the event-establishing sentences which were most strongly associated with the unexpected but event-related targets in the final sentences. Each of the two associates was then placed in a neutral carrier sentence. We controlled that none of the other words in these carrier sentences was associatively related to the target words. Importantly, the two carrier sentences did not build up a coherent event. We recorded EEG while participants read the carrier sentences followed by the same final sentences as in Experiment 1. The results showed that as in Experiment 1 the amplitude of the N400 elicited by both types of unexpected target words was larger than the N400 elicited by the highly expected target. Moreover, we found a global tendency towards the critical difference between event-related and event-unrelated unexpected targets which reached statistical significance only at parietal electrodes over the right hemisphere. Because the difference between event-related and event-unrelated conditions was larger when the sentences formed a coherent event compared to when they did not, our results suggest that associative priming alone cannot account for the N400 pattern observed in our Experiment 1 (and in the study by Metusalem et al.). However, because part of the effect remained, probably due to associative facilitation, the findings demonstrate that during discourse reading both event knowledge activation and simple word associations jointly contribute to the prediction process. The results highlight that multiple mechanisms underlie predictive language processing.

Abstract

Janssen and Barber (2012) reported two studies on the production of complex noun phrases (Spanish and French noun-adjective and noun-noun phrases). They found that production latencies depended only on the frequencies of the phrases, but not on the frequencies of the individual words. This pattern may be seen as evidence for lexical storage of phrases and against the traditional “words & rules” view of the representation of linguistic knowledge. We will discuss a series of experiments on the production of Dutch adjective-noun phrases. We replicated the phrase frequency effect seen by Janssen and Barber, but also found a robust effect of the frequency of the first word of the phrase. We argue that the phrase frequency effect arises during the conceptual preparation of the utterance and that the results are consistent with the view that phrases are composed by combining individual words, in line with the “words & rules” view.

Abstract

Frequent and predictable words are generally pronounced with less effort and are therefore acoustically more reduced than less frequent or unpredictable words. Local predictability can be operationalised by Transitional Probability (TP), which indicates how likely a word is to occur given its immediate context. We investigated whether and how probabilistic reduction effects on word durations change with adult age when reading aloud content words embedded in sentences.
The results showed equally large frequency effects on verb and noun durations for both younger (Mage = 20 years) and older (Mage = 68 years) adults. Backward TP also affected word duration for younger and older adults alike. ForwardTP, however, had no significant effect on word duration in either age group.
Our results resemble earlier findings of more robust BackwardTP effects compared to ForwardTP effects. Furthermore, unlike often reported decline in predictive processing with aging, probabilistic reduction effects remain stable across adulthood.

Abstract

A recurring criticism in the field of psycholinguistics and is the lack of ecological validity of experimental designs. For example, many experiments on sentence comprehension are conducted enclosed booths, where sentences are presented word by word on a computer screen. In addition, very often participants are instructed to make judgments that relate directly to the experimental manipulation. Thus, the contexts in which these processes are studied is quite restricted, which calls into question the generalizability of the results to more naturalistic environments. A possible solution to this problem is the use of virtual reality (VR) in psycholinguistic experiments. By immersing participants into a virtual environment, ecological validity can be increased while experimental control is maintained.
In the current experiment we combine electroencephalography (EEG) and VR to look at semantic processing in a more naturalistic setting. During the experiment, participants move through a visually rich virtual restaurant. Tables and avatars are placed in the restaurant and participants are instructed to stop at each table and look at the object (e.g. a plate with a steak) in front of the avatar. Then, the avatar will produce an utterance to accompany the object (e.g. “I think this steak is very nice”), in which the noun will either match (e.g. steak) or mismatch (e.g. mandarin) with the item on the table. Based on previous research, we predict a modulation of the N400, which should be larger in the mismatch than the match condition. Implications of the use of virtual reality for experimental research will be discussed.

Abstract

Fluctuations in pupil size have been shown to reflect variations in processing demands during language
comprehension. Increases in pupil diameter have been observed as a consequence of syntactic anomalies
(Schluroff 1982), increased syntactic complexity (Just & Carpenter 1993) and lexical ambiguity (Ben-
Nun 1986). An issue that has not received attention is whether pupil size also varies due to pragmatic
manipulations. In a pupillometry experiment, we investigated whether pupil diameter is sensitive to
increased processing demands as a result of comprehending an indirect request versus a statement. During
natural conversation, communication is often indirect. For example, in an appropriate context, ''It'' cold in
here'' is a request to shut the window, rather than a statement about room temperature (Holtgraves 1994).
We tested 49 Dutch participants (mean age = 20.8). They were presented with 120 picture-sentence
combinations that could either be interpreted as an indirect request (a picture of a window with the
sentence ''it's hot here'') or as a statement (a picture of a window with the sentence ''it's nice here''). The
indirect requests were non-conventional, i.e. they did not contain directive propositional content and were
not directly related to the underlying felicity conditions (Holtgraves 2002). In order to verify that the
indirect requests were recognized, participants were asked to decide after each combination whether or
not they heard a request. Based on the hypothesis that understanding this type of indirect utterances
requires additional inferences to be made on the part of the listener (e.g., Holtgraves 2002; Searle 1975;
Van Ackeren et al. 2012), we predicted a larger pupil diameter for indirect requests than statements. The
data were analyzed using linear mixed-effects models in R, which allow for simultaneous inclusion of
participants and items as random factors (Baayen, Davidson, & Bates 2008). The results revealed a larger
mean pupil size and a larger peak pupil size for indirect requests as compared to statements. In line with
previous studies on pupil size and language comprehension (e.g., Just & Carpenter 1993), this difference
was observed within a 1.5 second window after critical word onset. We suggest that the increase in pupil
size reflects additional on-line processing demands for the comprehension of non-conventional indirect
requests as compared to statements. This supports the idea that comprehending this type of indirect
request requires capacity demanding inferencing on the part of the listener. In addition, this study
demonstrates the usefulness of pupillometry as a tool for experimental research in pragmatics.

Abstract

Fluctuations in pupil size have been shown to reflect variations in processing demands during language
comprehension. Increases in pupil diameter have been observed as a consequence of syntactic anomalies
(Schluroff 1982), increased syntactic complexity (Just & Carpenter 1993) and lexical ambiguity (Ben-
Nun 1986). An issue that has not received attention is whether pupil size also varies due to pragmatic
manipulations. In a pupillometry experiment, we investigated whether pupil diameter is sensitive to
increased processing demands as a result of comprehending an indirect request versus a statement. During
natural conversation, communication is often indirect. For example, in an appropriate context, ''It'' cold in
here'' is a request to shut the window, rather than a statement about room temperature (Holtgraves 1994).
We tested 49 Dutch participants (mean age = 20.8). They were presented with 120 picture-sentence
combinations that could either be interpreted as an indirect request (a picture of a window with the
sentence ''it's hot here'') or as a statement (a picture of a window with the sentence ''it's nice here''). The
indirect requests were non-conventional, i.e. they did not contain directive propositional content and were
not directly related to the underlying felicity conditions (Holtgraves 2002). In order to verify that the
indirect requests were recognized, participants were asked to decide after each combination whether or
not they heard a request. Based on the hypothesis that understanding this type of indirect utterances
requires additional inferences to be made on the part of the listener (e.g., Holtgraves 2002; Searle 1975;
Van Ackeren et al. 2012), we predicted a larger pupil diameter for indirect requests than statements. The
data were analyzed using linear mixed-effects models in R, which allow for simultaneous inclusion of
participants and items as random factors (Baayen, Davidson, & Bates 2008). The results revealed a larger
mean pupil size and a larger peak pupil size for indirect requests as compared to statements. In line with
previous studies on pupil size and language comprehension (e.g., Just & Carpenter 1993), this difference
was observed within a 1.5 second window after critical word onset. We suggest that the increase in pupil
size reflects additional on-line processing demands for the comprehension of non-conventional indirect
requests as compared to statements. This supports the idea that comprehending this type of indirect
request requires capacity demanding inferencing on the part of the listener. In addition, this study
demonstrates the usefulness of pupillometry as a tool for experimental research in pragmatics.

Abstract

When processing visual objects, we integrate visual, linguistic and spatial information to form an episodic trace. Re-activating one aspect of the episodic trace of an object re-activates the entire bundle making all integrated information available. Using the blank screen paradigm [1], researchers observed that upon processing spoken linguistic input, participants tended to make eye movements on a blank screen, fixating locations that were previously occupied by objects mentioned in the linguistic utterance or were related. Ferreira and colleagues [2] suggested that 'looking at nothing' facilitated memory retrieval. However, this claim lacks convincing empirical support. In Experiment 1, Dutch participants looked at four-object-displays. Three objects were related to a spoken target word. Given the target word 'beker' (beaker), the display featured a phonological (a bear), a shape (a bobbin), a semantic (a fork) competitor, and an unrelated distractor (an umbrella). Participants were asked to name the objects as fast as possible. Subsequently, the objects disappeared. Participants fixated the center of the screen and listened to the target word. They had to carry out a semantic judgment task (indicating in which position an object had appeared that was semantically related to the objects) or a visual shape similarity judgment (indicating the position of the object similar in shape to the target). In both conditions, we observed that participants re-fixated the empty target location before responding. The set-up of Experiment 2 was identical except that we asked participants to maintain fixating the center of the screen while listening to the spoken word and responding. Performance accuracy was significantly lower in Experiment 2 than in Experiment 1. The results indicate that memory retrieval for objects is impaired when participants are not allowed to look at relevant, though empty locations. [1] Altmann, G. (2004). Language-mediated eye movements in the absence of a visual world: the 'blank screen paradigm'. Cognition, 93(2), B79-B87. [2] Ferreira, F., Apel, J., & Henderson, J. M. (2008). Taking a new look at looking at nothing. Trends Cogn Sci, 12(11), 405-410.

Abstract

Sentence formulation requires mapping pre-verbal messages onto linguistic structures. This message-to-language
mapping is often evaluated in eye-tracking tasks where speakers describe pictured events (The dog chased the mailman).
Speakers can begin sentence formulation by quickly selecting the first-fixated character as the sentential starting point
(lexical incrementality), or generating a rudimentary sentence plan based on their construal of the event gist before
selecting a starting point (hierarchical incrementality; Kuchinsky & Bock, 2010). Lexical incrementality predicts fast
divergence of fixations while hierarchical incrementality predicts slower divergence of fixations to the two characters
within 200ms of picture onset.

Abstract

Much evidence demonstrates cerebellar involvement in language [1] but a theoretical framework about its precise role is lacking. In cerebellar motor control an influential model ascribes the cerebellum a predictive role [2]. It has been argued that cerebellar nonmotor regions perform similar computations as motor regions, and both are involved in online prediction [2]. We test this hypothesis by administering repetitive transcranial magnetic stimulation (rTMS) to the right cerebellum, a region implicated in language [3] during a predictive language task. Methods Visual World task [4]: Participants' eye movements were recorded while they listened to sentences and looked at a computer display of an agent and 4 objects, one of which (the target) was mentioned in the sentence. In the Prediction condition the object could be predicted on the basis of the verb; on Control trials it could not. We hypothesised that rTMS to the right cerebellum should make target fixation slower in the Prediction condition, but not in the Control condition. TMS protocol: TMS was delivered between two task blocks. In the cerebellar rTMS group (n = 22) the stimulation site was 1cm down and 3cm right of the inion. Participants received 10min of 1Hz rTMS. In addition, we tested two control groups. In the vertex rTMS group (n = 21), rTMS was applied at the same intensity, duration and frequency as in the cerebellar rTMS group, but over the vertex. In the no stimulation group (n = 22) the coil was placed over the cerebellar stimulation site but no pulses were delivered. Results As hypothesised, participants in the cerebellar rTMS group took longer to fixate the target after TMS in the Prediction condition but not in the Control condition (Block-by-Condition interaction: F(1,21) = 8.848, p = 0.007). This interaction was not found in either the vertex rTMS group (F(1,20) = 0.064, p = 0.802) or the no stimulation group (F(1,21) = 2.461, p = 0.132). Conclusions Here, we show that rTMS to the right cerebellum selectively affects linguistic prediction. These results provide additional evidence that the cerebellum plays a role in language and support theoretical accounts that the cerebellum contributes to nonmotor functions, as it does to motor functions, by online prediction. 1. Strick et al (2009). Cerebellum and nonmotor function. Annu Rev Neurosci, 32, 413-134 2. Miall et al (1993). Is the cerebellum a Smith predictor. J Mot Behav, 25, 203-216 3. Marien et al (2001). The lateralised linguistic cerebellum: a review and a new hypothesis. Brain and Language, 79, 580-600 4. Altmann & Kamide (1999). Incremental interpretation at verbs. Cognition, 73, 247-264

Abstract

In sentence comprehension, readers and listeners often anticipate upcoming information (e.g., Altmann & Kamide, 1999). We investigated two aspects of this process, namely 1) what is pre-activated when anticipating an upcoming word (the contents of predictions), and 2) which cognitive mechanisms are involved. The contents of predictions at the level of meaning could be restricted to functional semantic attributes (e.g., edibility; Altmann & Kamide, 1999). However, when words are processed other types of information can also be activated, such as object shape representations. It is unknown whether this type of information is already activated when upcoming words are predicted. Forty-five adult participants listened to predictable words in sentence contexts (e.g., "In 1969 Neil Armstrong was the first man to set foot on the moon.") while looking at visual displays of four objects. Their eye movements were recorded. There were three conditions: target present (e.g., a moon and three distractor objects that were unrelated to the predictable word in terms of semantics, shape, and phonology), shape competitor (e.g., a tomato and three unrelated distractors), and distractors only (e.g., rice and three other unrelated objects). Across lists, the same pictures and sentences were used in the different conditions. We found that participants already showed a significant bias for the target object (moon) over unrelated distractors several seconds before the target was mentioned, demonstrating that they were predicting. Importantly, there was also a smaller but significant shape competitor (tomato) preference starting at about a second before critical word onset, consistent with predictions involving the referent’s shape. The mechanisms of predictions could be specific to language tasks, or language could use processing principles that are also used in other domains of cognition. We investigated whether performance in non-linguistic prediction is related to prediction in language processing, taking an individual differences approach. In addition to the language processing task, the participants performed a simple cueing task (after Posner, Nissen, & Ogden, 1978). They pressed one of two buttons (left/right) to indicate the location of an X symbol on the screen. On half of the trials, the X was preceded by a neutral cue (+). On the other half, an arrow cue pointing left (<) or right (>) indicated the upcoming X's location with 80% validity (i.e., the arrow cue was correct 80% of the time). The SOA between cue and target was 500 ms. Prediction was quantified as the mean response latency difference between the neutral and valid condition. This measure correlated positively with individual participants' anticipatory target and shape competitor preference (r = .27; r = .45), and was a significant predictor of anticipatory looks in linear mixed-effects regression models of the data. Participants who showed more facilitation from the arrow cues predicted to a higher degree in the linguistic task. This suggests that prediction in language processing may use mechanisms that are also used in other domains of cognition. References Altmann, G. T. M., & Kamide, Y. (1999). Incremental interpretation at verbs: Restricting the domain of subsequent reference. Cognition, 73(3), 247-264. Posner, M. I., Nissen, M. J., & Ogden, W. C. (1978). Attended and unattended processing modes: The role of set for spatial location. In: H.L. Pick, & I.J. Saltzman (Eds.), Modes of perceiving and processing information. Hillsdale, N.J.: Lawrence Erlbaum Associates.