Causal inference: relating language to event representations and events in the world.

Events are not isolated but rather linked to one another in various dimensions. In language processing, various sources of information-including real-world knowledge, (representations of) current linguistic input and non-linguistic visual context-help establish causal connections between events. In this review, we discuss causal inference in relation to events and event knowledge as one aspect of world knowledge, and their representations in language comprehension. To evaluate the mechanism and time course of causal inference, we gather insights from studies on (1) implicit causality/consequentiality as a specific form of causal inference regarding the protagonists of cause/consequence events, and (2) the processing of causal relations. We highlight the importance of methodology in measuring causal inference, compare the results from different research methods, and emphasize the contribution of the visual-world paradigm to achieve a better understanding of causal inference. We recommend that further investigations of causal inference consider temporally sensitive measures and more detailed contexts.

Analysing data from the psycholinguistic visual-world paradigm: Comparison of different analysis methods.

In this paper, we discuss key characteristics and typical experimental designs of the visual-world paradigm and compare different methods of analysing eye-movement data. We discuss the nature of the eye-movement data from a visual-world study and provide data analysis tutorials on ANOVA, t-tests, linear mixed-effects model, growth curve analysis, cluster-based permutation analysis, bootstrapped differences of timeseries, generalised additive modelling, and divergence point analysis to enable psycholinguists to apply each analytical method to their own data. We discuss advantages and disadvantages of each method and offer recommendations about how to select an appropriate method depending on the research question and the experimental design.

Situating language register across the ages, languages, modalities, and cultural aspects: Evidence from complementary methods.

In the present review paper by members of the collaborative research center "Register: Language Users' Knowledge of Situational-Functional Variation" (CRC 1412), we assess the pervasiveness of register phenomena across different time periods, languages, modalities, and cultures. We define "register" as recurring variation in language use depending on the function of language and on the social situation. Informed by rich data, we aim to better understand and model the knowledge involved in situation- and function-based use of language register. In order to achieve this goal, we are using complementary methods and measures. In the review, we start by clarifying the concept of "register", by reviewing the state of the art, and by setting out our methods and modeling goals. Against this background, we discuss three key challenges, two at the methodological level and one at the theoretical level: (1) To better uncover registers in text and spoken corpora, we propose changes to established analytical approaches. (2) To tease apart between-subject variability from the linguistic variability at issue (intra-individual situation-based register variability), we use within-subject designs and the modeling of individuals' social, language, and educational background. (3) We highlight a gap in cognitive modeling, viz. modeling the mental representations of register (processing), and present our first attempts at filling this gap. We argue that the targeted use of multiple complementary methods and measures supports investigating the pervasiveness of register phenomena and yields comprehensive insights into the cross-methodological robustness of register-related language variability. These comprehensive insights in turn provide a solid foundation for associated cognitive modeling.

Influence of Actor's Congruent and Incongruent Gaze on Language Processing.

In interpreting spoken sentences in event contexts, comprehenders both integrate their current interpretation of language with the recent past (e.g., events they have witnessed) and develop expectations about future event possibilities. Tense cues can disambiguate this linking but temporary ambiguity in their interpretation may lead comprehenders to also rely on further, situation-specific cues (e.g., an actor's gaze as a cue to his future actions). How comprehenders reconcile these different cues in real time is an open issue that we must address to accommodate comprehension. It has been suggested that relating a referential expression (e.g., a verb) to a referent (e.g., a recent event) is preferred over relying on other cues that refer to the future and are not yet referentially grounded ("recent-event preference"). Two visual-world eye-tracking experiments compared this recent-event preference with effects of an actor's gaze and of tense/temporal adverbs as cues to a future action event. The results revealed that people overall preferred to focus on the recent (vs. future) event target in their interpretation, suggesting that while a congruent and incongruent actor gaze can jointly with futuric linguistic cues neutralize the recent-event preference late in the sentence, the latter still plays a key role in shaping participants' initial verb-based event interpretation. Additional post-experimental memory tests provided insight into the longevity of the gaze effects.

Integration of Social Context vs. Linguistic Reference During Situated Language Processing.

Research findings on language comprehension suggest that many kinds of non-linguistic cues can rapidly affect language processing. Extant processing accounts of situated language comprehension model these rapid effects and are only beginning to accommodate the role of non-linguistic emotional, cues. To begin with a detailed characterization of distinct cues and their relative effects, three visual-world eye-tracking experiments assessed the relative importance of two cue types (action depictions vs. emotional facial expressions) as well as the effects of the degree of naturalness of social (facial) cues (smileys vs. natural faces). We predicted to replicate previously reported rapid effects of referentially mediated actions. In addition, we assessed distinct world-language relations. If how a cue is conveyed matters for its effect, then a verb referencing an action depiction should elicit a stronger immediate effect on visual attention and language comprehension than a speaker's emotional facial expression. The latter is mediated non-referentially via the emotional connotations of an adverb. The results replicated a pronounced facilitatory effect of action depiction (relative to no action depiction). By contrast, the facilitatory effect of a preceding speaker's emotional face was less pronounced. How the facial emotion was rendered mattered in that the emotional face effect was present with natural faces (Experiment 2) but not with smileys (Experiment 1). Experiment 3 suggests that contrast, i.e., strongly opposing emotional valence information vs. non-opposing valence information, might matter for the directionality of this effect. These results are the first step toward a more principled account of how distinct visual (social) cues modulate language processing, whereby the visual cues that are referenced by language (the depicted action), copresent (the depicted action), and more natural (the natural emotional prime face) tend to exert more pronounced effects.

Grounding Language Processing: The Added Value of Specifying Linguistic/Compositional Representations and Processes.

Abundant empirical evidence suggests that visual perception and motor responses are involved in language comprehension ('grounding'). However, when modeling the grounding of sentence comprehension on a word-by-word basis, linguistic representations and cognitive processes are rarely made fully explicit. This article reviews representational formalisms and associated (computational) models with a view to accommodating incremental and compositional grounding effects. Are different representation formats equally suitable and what mechanisms and representations do models assume to accommodate grounding effects? I argue that we must minimally specify compositional semantic representations, a set of incremental processes/mechanisms, and an explicit link from the assumed processes to measured behavior. Different representational formats can be contrasted in psycholinguistic modeling by holding the set of processes/mechanisms constant; contrasting different processes/mechanisms is possible by holding representations constant. Such psycholinguistic modeling could be applied across a wide range of experimental investigations and complement computational modeling.

Referential vs. Non-referential World-Language Relations: How Do They Modulate Language Comprehension in 4 to 5-Year-Olds, Younger, and Older Adults?

Age has been shown to influence language comprehension, with delays, for instance, in older adults' expectations about upcoming information. We examined to what extent expectations about upcoming event information (who-does-what-to-whom) change across the lifespan (in 4- to 5-year-old children, younger, and older adults) and as a function of different world-language relations. In a visual-world paradigm, participants in all three age groups inspected a speaker whose facial expression was either smiling or sad. Next they inspected two clipart agents (e.g., a smiling cat and a grumpy rat) depicted as acting upon a patient (e.g., a ladybug tickled by the cat and arrested by the rat). Control scenes featured the same three characters without the action depictions. While inspecting the depictions, comprehenders listened to a German sentence [e.g., Den Marienkäfer kitzelt vergnügt der Kater; literally: "The ladybug (object/patient) tickles happily the cat (subject/agent)"]. Referential verb-action relations (i.e., when the actions were present) could, in principle, cue the cat-agent and so could non-referential relations via links from the speaker's smile to "happily" and the cat's smile. We examined variation in participants' visual anticipation of the agent (the cat) before it was mentioned depending on (a) participant age and (b) whether the referentially mediated action depiction or the non-referentially associated speaker smile cued the agent. The action depictions rapidly boosted participants' visual anticipation of the agent, facilitating thematic role assignment in all age groups. By contrast, effects of the non-referentially cued speaker smile emerged in the younger adults only. We outline implications of these findings for processing accounts of the temporally coordinated interplay between listeners' age-dependent language comprehension, their interrogation of the visual context, and visual context influences.

The Role of Literal Features During Processing of Novel Verbal Metaphors.

When a word is used metaphorically (for example "walrus" in the sentence "The president is a walrus"), some features of that word's meaning ("very fat," "slow-moving") are carried across to the metaphoric interpretation while other features ("has large tusks," "lives near the north pole") are not. What happens to these features that relate only to the literal meaning during processing of novel metaphors? In four experiments, the present study examined the role of the feature of physical containment during processing of verbs of physical containment. That feature is used metaphorically to signify difficulty, such as "fenced in" in the sentence "the journalist's opinion was fenced in after the change in regime." Results of a lexical decision task showed that video clips displaying a ball being trapped by a box facilitated comprehension of verbs of physical containment when the words were presented in isolation. However, when the verbs were embedded in sentences that rendered their interpretation metaphorical in a novel way, no such facilitation was found, as evidenced by two eye-tracking reading studies. We interpret this as suggesting that features that are critical for understanding the encoded meaning of verbs but are not part of the novel metaphoric interpretation are ignored during the construction of metaphorical meaning. Results and limitations of the paradigm are discussed in relation to previous findings in the literature both on metaphor comprehension and on the interaction between language comprehension and the visual world.

Anticipating a future versus integrating a recent event? Evidence from eye-tracking.

When comprehending a spoken sentence that refers to a visually-presented event, comprehenders both integrate their current interpretation of language with the recent event and develop expectations about future event possibilities. Tense cues can disambiguate this linking, but temporary ambiguity in these cues may lead comprehenders to also rely on further, experience-based (e.g., frequency or an actor's gaze) cues. How comprehenders reconcile these different cues in real time is an open issue. Extant results suggest that comprehenders preferentially relate their unfolding interpretation to a recent event by inspecting its target object. We investigated to what extent this recent-event preference could be overridden by short-term experiential and situation-specific cues. In Experiments 1-2 participants saw substantially more future than recent events and listened to more sentences about future-events (75% in Experiment 1 and 88% in Experiment 2). Experiment 3 cued future target objects and event possibilities via an actor's gaze. The event frequency increase yielded a reduction in the recent event inspection preference early during sentence processing in Experiments 1-2 compared with Experiment 3 (where event frequency and utterance tense were balanced) but did not eliminate the overall recent-event preference. Actor gaze also modulated the recent-event preference, and jointly with future tense led to its reversal in Experiment 3. However, our results showed that people overall preferred to focus on recent (vs. future) events in their interpretation, suggesting that while two cues (actor gaze and short-term event frequency) can partially override the recent-event preference, the latter still plays a key role in shaping participants' interpretation.

Does direction matter? Linguistic asymmetries reflected in visual attention.

Language and vision interact in non-trivial ways. Linguistically, spatial utterances are often asymmetrical as they relate more stable objects (reference objects) to less stable objects (located objects). Researchers have claimed that such linguistic asymmetry should also be reflected in the allocation of visual attention when people process a depicted spatial relation described by spatial language. More specifically, it was assumed that people move their attention from the reference object to the located object. However, recent theoretical and empirical findings challenge the directionality of this attentional shift. In this article, we present the results of an empirical study based on predictions generated by computational cognitive models implementing different directionalities of attention. Moreover, we thoroughly analyze the computational models. While our results do not favor any of the implemented directionalities of attention, we found that two unknown sources of geometric information affect spatial language understanding. We provide modifications to the computational models that substantially improve their performance on empirical data.

Eye Tracking During Visually Situated Language Comprehension: Flexibility and Limitations in Uncovering Visual Context Effects.

The present work is a description and an assessment of a methodology designed to quantify different aspects of the interaction between language processing and the perception of the visual world. The recording of eye-gaze patterns has provided good evidence for the contribution of both the visual context and linguistic/world knowledge to language comprehension. Initial research assessed object-context effects to test theories of modularity in language processing. In the introduction, we describe how subsequent investigations have taken the role of the wider visual context in language processing as a research topic in its own right, asking questions such as how our visual perception of events and of speakers contributes to comprehension informed by comprehenders' experience. Among the examined aspects of the visual context are actions, events, a speaker's gaze, and emotional facial expressions, as well as spatial object configurations. Following an overview of the eye-tracking method and its different applications, we list the key steps of the methodology in the protocol, illustrating how to successfully use it to study visually-situated language comprehension. A final section presents three sets of representative results and illustrates the benefits and limitations of eye tracking for investigating the interplay between the perception of the visual world and language comprehension.

Corrigendum: Semantic Interference and Facilitation: Understanding the Integration of Spatial Distance and Conceptual Similarity During Sentence Reading.

[This corrects the article DOI: 10.3389/fpsyg.2018.00718.].

Semantic Interference and Facilitation: Understanding the Integration of Spatial Distance and Conceptual Similarity During Sentence Reading.

Existing evidence has shown a processing advantage (or facilitation) when representations derived from a non-linguistic context (spatial proximity depicted by gambling cards moving together) match the semantic content of an ensuing sentence. A match, inspired by conceptual metaphors such as 'similarity is closeness' would, for instance, involve cards moving closer together and the sentence relates similarity between abstract concepts such as war and battle. However, other studies have reported a disadvantage (or interference) for congruence between the semantic content of a sentence and representations of spatial distance derived from this sort of non-linguistic context. In the present article, we investigate the cognitive mechanisms underlying the interaction between the representations of spatial distance and sentence processing. In two eye-tracking experiments, we tested the predictions of a mechanism that considers the competition, activation, and decay of visually and linguistically derived representations as key aspects in determining the qualitative pattern and time course of that interaction. Critical trials presented two playing cards, each showing a written abstract noun; the cards turned around, obscuring the nouns, and moved either farther apart or closer together. Participants then read a sentence expressing either semantic similarity or difference between these two nouns. When instructed to attend to the nouns on the cards (Experiment 1), participants' total reading times revealed interference between spatial distance (e.g., closeness) and semantic relations (similarity) as soon as the sentence explicitly conveyed similarity. But when instructed to attend to the cards (Experiment 2), cards approaching (vs. moving apart) elicited first interference (when similarity was implicit) and then facilitation (when similarity was made explicit) during sentence reading. We discuss these findings in the context of a competition mechanism of interference and facilitation effects.

Distinct effects of different visual cues on sentence comprehension and later recall: The case of speaker gaze versus depicted actions.

Language-processing accounts are beginning to accommodate different visual context effects, but they remain underspecified regarding differences between cues, both during sentence comprehension and subsequent recall. We monitored participants' eye movements to mentioned characters while they listened to transitive sentences. We varied whether speaker gaze, a depicted action, neither, or both of these visual cues were available, as well as whether both cues were deictic (Experiment 1) or only speaker gaze (Experiment 2). Speaker gaze affected eye movements during comprehension similarly early to a single deictic action depiction, but significantly earlier than non-deictic action depictions; conversely, depicted actions but not speaker gaze positively affected later recall of sentence content. Thus, cue type and cue-language relations must be accommodated in characterising real-time situated language comprehension and subsequent recall of sentence content.

Extending Situated Language Comprehension (Accounts) with Speaker and Comprehender Characteristics: Toward Socially Situated Interpretation.

More and more findings suggest a tight temporal coupling between (non-linguistic) socially interpreted context and language processing. Still, real-time language processing accounts remain largely elusive with respect to the influence of biological (e.g., age) and experiential (e.g., world and moral knowledge) comprehender characteristics and the influence of the 'socially interpreted' context, as for instance provided by the speaker. This context could include actions, facial expressions, a speaker's voice or gaze, and gestures among others. We review findings from social psychology, sociolinguistics and psycholinguistics to highlight the relevance of (the interplay between) the socially interpreted context and comprehender characteristics for language processing. The review informs the extension of an extant real-time processing account (already featuring a coordinated interplay between language comprehension and the non-linguistic visual context) with a variable ('ProCom') that captures characteristics of the language user and with a first approximation of the comprehender's speaker representation. Extending the CIA to the sCIA (social Coordinated Interplay Account) is the first step toward a real-time language comprehension account which might eventually accommodate the socially situated communicative interplay between comprehenders and speakers.

Multisensory brand search: How the meaning of sounds guides consumers' visual attention.

Building on models of crossmodal attention, the present research proposes that brand search is inherently multisensory, in that the consumers' visual search for a specific brand can be facilitated by semantically related stimuli that are presented in another sensory modality. A series of 5 experiments demonstrates that the presentation of spatially nonpredictive auditory stimuli associated with products (e.g., usage sounds or product-related jingles) can crossmodally facilitate consumers' visual search for, and selection of, products. Eye-tracking data (Experiment 2) revealed that the crossmodal effect of auditory cues on visual search manifested itself not only in RTs, but also in the earliest stages of visual attentional processing, thus suggesting that the semantic information embedded within sounds can modulate the perceptual saliency of the target products' visual representations. Crossmodal facilitation was even observed for newly learnt associations between unfamiliar brands and sonic logos, implicating multisensory short-term learning in establishing audiovisual semantic associations. The facilitation effect was stronger when searching complex rather than simple visual displays, thus suggesting a modulatory role of perceptual load. (PsycINFO Database Record

Visual attention during spatial language comprehension.

Spatial terms such as "above", "in front of", and "on the left of" are all essential for describing the location of one object relative to another object in everyday communication. Apprehending such spatial relations involves relating linguistic to object representations by means of attention. This requires at least one attentional shift, and models such as the Attentional Vector Sum (AVS) predict the direction of that attention shift, from the sausage to the box for spatial utterances such as "The box is above the sausage". To the extent that this prediction generalizes to overt gaze shifts, a listener's visual attention should shift from the sausage to the box. However, listeners tend to rapidly look at referents in their order of mention and even anticipate them based on linguistic cues, a behavior that predicts a converse attentional shift from the box to the sausage. Four eye-tracking experiments assessed the role of overt attention in spatial language comprehension by examining to which extent visual attention is guided by words in the utterance and to which extent it also shifts "against the grain" of the unfolding sentence. The outcome suggests that comprehenders' visual attention is predominantly guided by their interpretation of the spatial description. Visual shifts against the grain occurred only when comprehenders had some extra time, and their absence did not affect comprehension accuracy. However, the timing of this reverse gaze shift on a trial correlated with that trial's verification time. Thus, while the timing of these gaze shifts is subtly related to the verification time, their presence is not necessary for successful verification of spatial relations.

Spatial distance effects on incremental semantic interpretation of abstract sentences: evidence from eye tracking.

A large body of evidence has shown that visual context information can rapidly modulate language comprehension for concrete sentences and when it is mediated by a referential or a lexical-semantic link. What has not yet been examined is whether visual context can also modulate comprehension of abstract sentences incrementally when it is neither referenced by, nor lexically associated with, the sentence. Three eye-tracking reading experiments examined the effects of spatial distance between words (Experiment 1) and objects (Experiment 2 and 3) on participants' reading times for sentences that convey similarity or difference between two abstract nouns (e.g., 'Peace and war are certainly different...'). Before reading the sentence, participants inspected a visual context with two playing cards that moved either far apart or close together. In Experiment 1, the cards turned and showed the first two nouns of the sentence (e.g., 'peace', 'war'). In Experiments 2 and 3, they turned but remained blank. Participants' reading times at the adjective (Experiment 1: first-pass reading time; Experiment 2: total times) and at the second noun phrase (Experiment 3: first-pass times) were faster for sentences that expressed similarity when the preceding words/objects were close together (vs. far apart) and for sentences that expressed dissimilarity when the preceding words/objects were far apart (vs. close together). Thus, spatial distance between words or entirely unrelated objects can rapidly and incrementally modulate the semantic interpretation of abstract sentences.