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Language models based on artificial neural networks increasingly capture key aspects of how humans process sentences. Most notably, model-based surprisals predict event-related potentials such as N400 amplitudes during parsing. Assuming that these models represent realistic estimates of human linguistic experience, their success in modelling language processing raises the possibility that the human processing system relies on no other principles than the general architecture of language models and on sufficient linguistic input. Here, we test this hypothesis on N400 effects observed during the processing of verb-final sentences in German, Basque, and Hindi. By stacking Bayesian generalised additive models, we show that, in each language, N400 amplitudes and topographies in the region of the verb are best predicted when model-based surprisals are complemented by an Agent Preference principle that transiently interprets initial role-ambiguous NPs as agents, leading to reanalysis when this interpretation fails. Our findings demonstrate the need for this principle independently of usage frequencies and structural differences between languages. The principle has an unequal force, however. Compared to surprisal, its effect is weakest in German, stronger in Hindi, and still stronger in Basque. This gradient is correlated with the extent to which grammars allow unmarked NPs to be patients, a structural feature that boosts reanalysis effects. We conclude that language models gain more neurobiological plausibility by incorporating an Agent Preference. Conversely, theories of human processing profit from incorporating surprisal estimates in addition to principles like the Agent Preference, which arguably have distinct evolutionary roots.

Comprehenders across languages tend to interpret role-ambiguous arguments as the subject or the agent of a sentence during parsing. However, the evidence for such a subject/agent preference rests on the comprehension of transitive, active-voice sentences where agents/subjects canonically precede patients/objects. The evidence is thus potentially confounded by the canonical order of arguments. Transitive sentence stimuli additionally conflate the semantic agent role and the syntactic subject function. We resolve these two confounds in an experiment on the comprehension of intransitive sentences in Basque. When exposed to sentence-initial role-ambiguous arguments, comprehenders preferentially interpreted these as agents and had to revise their interpretation when the verb disambiguated to patient-initial readings. The revision was reflected in an N400 component in ERPs and a decrease in power in the alpha and lower beta bands. This finding suggests that sentence processing is guided by a top-down heuristic to interpret ambiguous arguments as agents, independently of word order and independently of transitivity.

In recent years, the field of psycholinguistics has seen an increased focus on the study of typologically diverse languages. Expanding cross-linguistic coverage is critical to tease apart those aspects of language processing that are general to the architecture of the human language processing system compared to those that are fine-tuned to the properties of the specific language one speaks. In this chapter, we present an overview of research in this area and describe in detail the kinds of experimental methods that are employed, with a particular focus on methods and procedures that have been developed for undertaking research on language processing outside of more familiar lab-based settings.

The language comprehension system preferentially assumes that agents come first during incremental processing. While this might reflect a biologically fixed bias, shared with other domains and other species, the evidence is limited to languages that place agents first, and so the bias could also be learned from usage frequency. Here, we probe the bias with electroencephalograph (EEG)y in Äiwoo, a language that by default places patients first, but where sentence-initial nouns are still locally ambiguous between patient or agent roles. Comprehenders transiently interpreted non-human nouns as patients, eliciting a negativity when disambiguation was toward the less common agent-initial order. By contrast and against frequencies, human nouns were transiently interpreted as agents, eliciting a N400-like negativity when disambiguation was toward patient-initial order. Consistent with the notion of a fixed property, the agent bias is robust against usage frequency for human referents. However, this bias can be reversed by frequency experience for non-human referents.

A central aspect of human experience and communication is understanding events in terms of agent (“doer”) and patient (“undergoer” of action) roles. These event roles are rooted in general cognition and prominently encoded in language, with agents appearing as more salient and preferred over patients. An unresolved question is whether this preference for agents already operates during apprehension, that is, the earliest stage of event processing, and if so, whether the effect persists across different animacy configurations and task demands. Here we contrast event apprehension in two tasks and two languages that encode agents differently; Basque, a language that explicitly case-marks agents (‘ergative’), and Spanish, which does not mark agents. In two brief exposure experiments, native Basqueand Spanish speakers saw pictures for only 300 ms, and subsequently described them or answered probe questions about them. We compared eye fixations and behavioral correlates of event role extraction with Bayesian regression. Agents received more attention and were recognized better across languages and tasks. At the same time, language and task demands affected the attention to agents. Our findings show that a general preference for agents exists in event apprehension, but it can be modulated by task and language demands.

Languages differ in how they mark the dependencies between verbs and arguments, e.g., by case. An eye tracking and EEG picture description study examined the influence of case marking on the time course of sentence planning in Basque and Swiss German. While German assigns an unmarked (nominative) case to subjects, Basque specifically marks agent arguments through ergative case. Fixations to agents and event-related synchronization (ERS) in the theta and alpha frequency bands, as well as desynchronization (ERD) in the alpha and beta bands revealed multiple effects of case marking on the time course of early sentence planning. Speakers decided on case marking under planning early when preparing sentences with ergative-marked agents in Basque, whereas sentences with unmarked agents allowed delaying structural commitment across languages. These findings support hierarchically incremental accounts of sentence planning and highlight how cross-linguistic differences shape the neural dynamics underpinning language use.

Languages differ in how they mark the dependencies between verbs and arguments, e.g., by case. An eye tracking and EEG picture description study examined the influence of case marking on the time course of sentence planning in Basque and Swiss German. While German assigns an unmarked (nominative) case to subjects, Basque specifically marks agent arguments through ergative case. Fixations to agents and event-related synchronization (ERS) in the theta and alpha frequency bands, as well as desynchronization (ERD) in the alpha and beta bands revealed multiple effects of case marking on the time course of early sentence planning. Speakers decided on case marking under planning early when preparing sentences with ergative-marked agents in Basque, whereas sentences with unmarked agents allowed delaying structural commitment across languages. These findings support hierarchically incremental accounts of sentence planning and highlight how cross-linguistic differences shape the neural dynamics underpinning language use.

Planning to speak is a challenge for the brain, and the challenge varies between and within languages. Yet, little is known about how neural processes react to these variable challenges beyond the planning of individual words. Here, we examine how fundamental differences in syntax shape the time course of sentence planning. Most languages treat alike (i.e., align with each other) the 2 uses of a word like “gardener” in “the gardener crouched” and in “the gardener planted trees.” A minority keeps these formally distinct by adding special marking in 1 case, and some languages display both aligned and nonaligned expressions. Exploiting such a contrast in Hindi, we used electroencephalography (EEG) and eye tracking to suggest that this difference is associated with distinct patterns of neural processing and gaze behavior during early planning stages, preceding phonological word form preparation. Planning sentences with aligned expressions induces larger synchronization in the theta frequency band, suggesting higher working memory engagement, and more visual attention to agents than planning nonaligned sentences, suggesting delayed commitment to the relational details of the event. Furthermore, plain, unmarked expressions are associated with larger desynchronization in the alpha band than expressions with special markers, suggesting more engagement in information processing to keep overlapping structures distinct during planning. Our findings contrast with the observation that the form of aligned expressions is simpler, and they suggest that the global preference for alignment is driven not by its neurophysiological effect on sentence planning but by other sources, possibly by aspects of production flexibility and fluency or by sentence comprehension. This challenges current theories on how production and comprehension may affect the evolution and distribution of syntactic variants in the world’s languages.

Human experience and communication are centred on events, and event apprehension is a rapid process that draws on the visual perception and immediate categorization of event roles (“who does what to whom”). We demonstrate a role for syntactic structure in visual information uptake for event apprehension. An event structure foregrounding either the agent or patient was activated during speaking, transiently modulating the apprehension of subsequently viewed unrelated events. Speakers of Dutch described pictures with actives and passives (agent and patient foregrounding, respectively). First fixations on pictures of unrelated events that were briefly presented (for 300 ms) next were influenced by the active or passive structure of the previously produced sentence. Going beyond the study of how single words cue object perception, we show that sentence structure guides the viewpoint taken during rapid event apprehension.

Theories of incremental sentence production make different assumptions about when speakers encode information about described events and when verbs are selected, accordingly. An eye tracking experiment on German testing the predictions from linear and hierarchical incrementality about the timing of event encoding and verb planning is reported. In the experiment, participants described depictions of two-participant events with sentences that differed in voice and word order. Verb-medial active sentences and actives and passives with sentence-final verbs were compared. Linear incrementality predicts that sentences with verbs placed early differ from verb-final sentences because verbs are assumed to only be planned shortly before they are articulated. By contrast, hierarchical incrementality assumes that speakers start planning with relational encoding of the event. A weak version of hierarchical incrementality assumes that only the action is encoded at the outset of formulation and selection of lexical verbs only occurs shortly before they are articulated, leading to the prediction of different fixation patterns for verb-medial and verb-final sentences. A strong version of hierarchical incrementality predicts no differences between verb-medial and verb-final sentences because it assumes that verbs are always lexically selected early in the formulation process. Based on growth curve analyses of fixations to agent and patient characters in the described pictures, and the influence of character humanness and the lack of an influence of the visual salience of characters on speakers' choice of active or passive voice, the current results suggest that while verb planning does not necessarily occur early during formulation, speakers of German always create an event representation early.

The voice system of Tagalog has been proposed to be symmetrical in the sense that there are no morphologically unmarked voice forms. This stands in contrast to asymmetrical voice systems, which exhibit unmarked and marked voices (e.g. active and passive in German). This article investigates the psycholinguistic processing consequences of the potential (a)symmetries in the voice systems of Tagalog and German by analyzing changes in cognitive load during sentence production. Tagalog and German native speakers’ pupil diameters were recorded while they produced sentences with different voice markings. Growth-curve analyses of the shape of task-evoked pupillary responses revealed that processing-load changes were similar for different voices in the symmetrical voice system of Tagalog. By contrast, actives and passives in the asymmetrical voice system of German exhibited different patterns of processing-load changes during sentence production. This is interpreted as supporting the notion of (relative) symmetry in the Tagalog voice system. Mental effort during sentence planning changes in different ways in the two languages because the grammatical architecture of their voice systems is different. Additionally, an anti-Patient bias in sentence production was found: linking patients to the subject function seems to be associated with greater cognitive effort. This anti-Patient bias in production adds converging evidence to ‘subject preferences’ reported in the sentence-comprehension literature.

Studies on anticipatory processes during sentence comprehension often focus on the prediction of postverbal direct objects. In subject-initial languages (the target of most studies so far), however, the position in the sentence, the syntactic function, and the semantic role of arguments are often conflated. For example, in the sentence “The frog will eat the fly” the syntactic object (“fly”) is at the same time also the last word and the patient argument of the verb. It is therefore not apparent which kind of information listeners orient to for predictive processing during sentence comprehension. A visual world eye tracking study on the verb-initial language Tagalog (Austronesian) tested what kind of information listeners use to anticipate upcoming postverbal linguistic input. The grammatical structure of Tagalog allows to test whether listeners' anticipatory gaze behavior is guided by predictions of the linear order of words, by syntactic functions (e.g., subject/object), or by semantic roles (agent/patient). Participants heard sentences of the type “Eat frog fly” or “Eat fly frog” (both meaning “The frog will eat the fly”) while looking at displays containing an agent referent (“frog”), a patient referent (“fly”) and a distractor. The verb carried morphological marking that allowed the order and syntactic function of agent and patient to be inferred. After having heard the verb, listeners fixated on the agent irrespective of its syntactic function or position in the sentence. While hearing the first-mentioned argument, listeners fixated on the corresponding referent in the display accordingly and then initiated saccades to the last-mentioned referent before it was encountered. The results indicate that listeners used verbal semantics to identify referents and their semantic roles early; information about word order or syntactic functions did not influence anticipatory gaze behavior directly after the verb was heard. In this verb-initial language, event semantics t

This paper describes a computerized alternative to glottochronology for estimating elapsed time since parent languages diverged into daughter languages. The method, developed by the Automated Similarity Judgment Program (ASJP) consortium, is different from glottochronology in four major respects: (1) it is automated and thus is more objective, (2) it applies a uniform analytical approach to a single database of worldwide languages, (3) it is based on lexical similarity as determined from Levenshtein (edit) distances rather than on cognate percentages, and (4) it provides a formula for date calculation that mathematically recognizes the lexical heterogeneity of individual languages, including parent languages just before their breakup into daughter languages. Automated judgments of lexical similarity for groups of related languages are calibrated with historical, epigraphic, and archaeological divergence dates for 52 language groups. The discrepancies between estimated and calibration dates are found to be on average 29% as large as the estimated dates themselves, a figure that does not differ significantly among language families. As a resource for further research that may require dates of known level of accuracy, we offer a list of ASJP time depths for nearly all the world’s recognized language families and for many subfamilies.