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We present a visual world eye-tracking study on Tseltal (a Mayan language) and investigate whether verbal information can be used to anticipate an upcoming referent. Basic word order in transitive sentences in Tseltal is Verb--Object--Subject (VOS). The verb is usually encountered first, making argument structure and syntactic information available at the outset, which should facilitate anticipation of the post-verbal arguments. Tseltal speakers listened to verb-initial sentences with either an object-predictive verb (e.g., "eat") or a general verb (e.g., "look for") (e.g., "Ya slo'/sle ta stukel on te kereme," "Is eating/is looking (for) by himself the avocado the boy/" "The boy is eating/is looking (for) an avocado by himself") while seeing a visual display showing one potential referent (e.g., avocado) and three distractors (e.g., bag, toy car, coffee grinder). We manipulated verb type (predictive vs. general) and recorded participants' eye movements while they listened and inspected the visual scene. Participants' fixations to the target referent were analyzed using multilevel logistic regression models. Shortly after hearing the predictive verb, participants fixated the target object before it was mentioned. In contrast, when the verb was general, fixations to the target only started to increase once the object was heard. Our results suggest that Tseltal hearers pre-activate semantic features of the grammatical object prior to its linguistic expression. This provides evidence from a verb-initial language for online incremental semantic interpretation and anticipatory processing during language comprehension. These processes are comparable to the ones identified in subject-initial languages, which is consistent with the notion that different languages follow similar universal processing principles.

The rate at which young children are directly spoken to varies due to many factors, including (a) caregiver ideas about children as conversational partners and (b) the organization of everyday life. Prior work suggests cross-cultural variation in rates of child-directed speech is due to the former factor, but has been fraught with confounds in comparing postindustrial and subsistence farming communities. We investigate the daylong language environments of children (0;0-3;0) on Rossel Island, Papua New Guinea, a small-scale traditional community where prior ethnographic study demonstrated contingency-seeking child interaction styles. In fact, children were infrequently directly addressed and linguistic input rate was primarily affected by situational factors, though children's vocalization maturity showed no developmental delay. We compare the input characteristics between this community and a Tseltal Mayan one in which near-parallel methods produced comparable results, then briefly discuss the models and mechanisms for learning best supported by our findings.

Daylong at-home audio recordings from 10 Tseltal Mayan children (0;2-3;0; Southern Mexico) were analyzed for how often children engaged in verbal interaction with others and whether their speech environment changed with age, time of day, household size, and number of speakers present. Children were infrequently directly spoken to, with most directed speech coming from adults, and no increase with age. Most directed speech came in the mornings, and interactional peaks contained nearly four times the baseline rate of directed speech. Coarse indicators of children's language development (babbling, first words, first word combinations) suggest that Tseltal children manage to extract the linguistic information they need despite minimal directed speech. Multiple proposals for how they might do so are discussed.

Speaker transitions in conversation are often brief, with minimalvocal overlap. Signed languages appear to defy this patternwith frequent, long spans of simultaneous signing. But recentevidence suggests that turn boundaries in signed languagemay only include the content-bearing parts of the turn (fromthe first stroke to the last), and not all turn-related movement(from first preparation to final retraction). We tested whethersigners were able to anticipate “stroke-to-stroke” turn boundarieswith only minimal conversational context. We found that,indeed, signers anticipated turn boundaries at the ends of turnfinalstrokes. Signers often responded early, especially whenthe turn was long or contained multiple possible end points.Early responses for long turns were especially apparent forinterrogatives—long interrogative turns showed much greateranticipation compared to short ones.

Studies of mother-infant interaction indicate that sensitivity to interactional timing begins developing around 3–4months, but there is currently no evidence bearing on when children start to understand conversational timing rules; how totransition from one speaker to the next. We showed twelve- and thirty-month-old children videos of conversation featuringpuppets using typical (200ms inter-turn silence) and atypical (1200ms silence and 3+ syllables vocal overlap) turn-timing. Weassessed children’s timing preferences by then showing them the two puppets (typical and atypical) for a sustained period andthen by asking them to choose one puppet to hold. Preliminary results suggest that, overall, children were more likely todiscriminate between typical and atypical timing for vocal overlap than long silent gaps. This maps nicely onto findings aboutchildren’s spontaneous turn-taking: they learn to minimize overlaps before gaps.