Overrated gaps: Inter-speaker gaps provide limited information about the timing of turns in conversation.

Corpus analyses have shown that turn-taking in conversation is much faster than laboratory studies of speech planning would predict. To explain fast turn-taking, Levinson and Torreira (2015) proposed that speakers are highly proactive: They begin to plan a response to their interlocutor's turn as soon as they have understood its gist, and launch this planned response when the turn-end is imminent. Thus, fast turn-taking is possible because speakers use the time while their partner is talking to plan their own utterance. In the present study, we asked how much time upcoming speakers actually have to plan their utterances. Following earlier psycholinguistic work, we used transcripts of spoken conversations in Dutch, German, and English. These transcripts consisted of segments, which are continuous stretches of speech by one speaker. In the psycholinguistic and phonetic literature, such segments have often been used as proxies for turns. We found that in all three corpora, large proportions of the segments comprised of only one or two words, which on our estimate does not give the next speaker enough time to fully plan a response. Further analyses showed that speakers indeed often did not respond to the immediately preceding segment of their partner, but continued an earlier segment of their own. More generally, our findings suggest that speech segments derived from transcribed corpora do not necessarily correspond to turns, and the gaps between speech segments therefore only provide limited information about the planning and timing of turns.

Forgotten Little Words: How Backchannels and Particles May Facilitate Speech Planning in Conversation?

In everyday conversation, turns often follow each other immediately or overlap in time. It has been proposed that speakers achieve this tight temporal coordination between their turns by engaging in linguistic dual-tasking, i.e., by beginning to plan their utterance during the preceding turn. This raises the question of how speakers manage to co-ordinate speech planning and listening with each other. Experimental work addressing this issue has mostly concerned the capacity demands and interference arising when speakers retrieve some content words while listening to others. However, many contributions to conversations are not content words, but backchannels, such as "hm". Backchannels do not provide much conceptual content and are therefore easy to plan and respond to. To estimate how much they might facilitate speech planning in conversation, we determined their frequency in a Dutch and a German corpus of conversational speech. We found that 19% of the contributions in the Dutch corpus, and 16% of contributions in the German corpus were backchannels. In addition, many turns began with fillers or particles, most often translation equivalents of "yes" or "no," which are likewise easy to plan. We proposed that to generate comprehensive models of using language in conversation psycholinguists should study not only the generation and processing of content words, as is commonly done, but also consider backchannels, fillers, and particles.

Working Together: Contributions of Corpus Analyses and Experimental Psycholinguistics to Understanding Conversation.

As conversation is the most important way of using language, linguists and psychologists should combine forces to investigate how interlocutors deal with the cognitive demands arising during conversation. Linguistic analyses of corpora of conversation are needed to understand the structure of conversations, and experimental work is indispensable for understanding the underlying cognitive processes. We argue that joint consideration of corpus and experimental data is most informative when the utterances elicited in a lab experiment match those extracted from a corpus in relevant ways. This requirement to compare like with like seems obvious but is not trivial to achieve. To illustrate this approach, we report two experiments where responses to polar (yes/no) questions were elicited in the lab and the response latencies were compared to gaps between polar questions and answers in a corpus of conversational speech. We found, as expected, that responses were given faster when they were easy to plan and planning could be initiated earlier than when they were harder to plan and planning was initiated later. Overall, in all but one condition, the latencies were longer than one would expect based on the analyses of corpus data. We discuss the implication of this partial match between the data sets and more generally how corpus and experimental data can best be combined in studies of conversation.

Development of spatial preferences for counting and picture naming.

The direction of object enumeration reflects children's enculturation but previous work on the development of such spatial preferences has been inconsistent. Therefore, we documented directional preferences in finger counting, object counting, and picture naming for children (4 groups from 3 to 6 years, N = 104) and adults (N = 56). We found a right-side preference for finger counting in 3- to 6-year-olds and a left-side preference for counting objects and naming pictures by 6 years of age. Children were consistent in their special preferences when comparing object counting and picture naming, but not in other task pairings. Finally, spatial preferences were not related to cardinality comprehension. These results, together with other recent work, suggest a gradual development of spatial-numerical associations from early non-directional mappings into culturally constrained directional mappings.

Benefit of physiotherapeutic treatment in children with torticollis.

INTRODUCTION: The incidence of torticollis, which is often accompanied by some degree of plagiocephaly in infants, has remained increased since the introduction of the supine sleeping position to prevent sudden infant death. Recently, instruments allowing quantitative measurement of torticollis and related pathology have been developed and validated. The aim of the present study was to monitor a cohort of children with torticollis using a standardised protocol including valid and reliable measurements. METHODS: A total of 136 infants diagnosed with torticollis and referred to physiotherapeutic treatment in four paediatric departments were included (October 2009-April 2011). Trained and calibrated physiotherapists assessed their cervical range of motion (ROM), cervical muscle function and severity of plagiocephaly prior to and after the treatment period. RESULTS: The infants' median age was three months at inclusion and seven months at the end of the treatment period that comprised a median of five treatment sessions. Initially, 52% and 54% presented with ROM deficits in rotation and lateral flexion, respectively. After treatment, these parts were reduced to 6% and 14%, and the magnitudes of the remaining ROM deficits were substantially reduced. Plagiocephaly improved in 82, remained unchanged in 18 and deteriorated in five of 105 infants with complete follow-up. Symmetrical or almost symmetrical muscle function was achieved in 93% (n = 101). CONCLUSION: A successful outcome was achieved in the majority (90%) of children with torticollis with less than ten physiotherapeutic treatment sessions. FUNDING: not relevant. TRIAL REGISTRATION: not relevant.

The end-state comfort effect in 3- to 8-year-old children in two object manipulation tasks.

The aim of the study was to compare 3- to 8-year-old children's propensity to anticipate a comfortable hand posture at the end of a grasping movement (end-state comfort effect) between two different object manipulation tasks, the bar-transport task, and the overturned-glass task. In the bar-transport task, participants were asked to insert a vertically positioned bar into a small opening of a box. In the overturned-glass task, participants were asked to put an overturned-glass right-side-up on a coaster. Half of the participants experienced action effects (lights) as a consequence of their movements (AE groups), while the other half of the participants did not (No-AE groups). While there was no difference between the AE and No-AE groups, end-state comfort performance differed across age as well as between tasks. Results revealed a significant increase in end-state comfort performance in the bar-transport task from 13% in the 3-year-olds to 94% in the 8-year-olds. Interestingly, the number of children grasping the bar according to end-state comfort doubled from 3 to 4 years and from 4 to 5 years of age. In the overturned-glass task an increase in end-state comfort performance from already 63% in the 3-year-olds to 100% in the 8-year-olds was significant as well. When comparing end-state comfort performance across tasks, results showed that 3- and 4-year-old children were better at manipulating the glass as compared to manipulating the bar, most probably, because children are more familiar with manipulating glasses. Together, these results suggest that preschool years are an important period for the development of motor planning in which the familiarity with the object involved in the task plays a significant role in children's ability to plan their movements according to end-state comfort.

Eighteen- and 24-month-old infants correct others in anticipation of action mistakes.

Much of human communication and collaboration is predicated on making predictions about others' actions. Humans frequently use predictions about others' action mistakes to correct others and spare them mistakes. Such anticipatory correcting reveals a social motivation for unsolicited helping. Cognitively, it requires forward inferences about others' actions through mental attributions of goal and reality representations. The current study shows that infants spontaneously intervene when an adult is mistaken about the location of an object she is about to retrieve. Infants pointed out a correct location for an adult before she was about to commit a mistake. Infants did not intervene in control conditions when the adult had witnessed the misplacement, or when she did not intend to retrieve the misplaced object. Results suggest that preverbal infants anticipate a person's mistaken action through mental attributions of both her goal and reality representations, and correct her proactively by spontaneously providing unsolicited information.

18-Month-Olds Predict Specific Action Mistakes Through Attribution of False Belief, Not Ignorance, and Intervene Accordingly.

This study employed a new "anticipatory intervening" paradigm to tease apart false belief and ignorance-based interpretations of 18-month-olds' helpful informing. We investigated in three experiments whether 18-month-old infants inform an adult selectively about one of the two locations depending on the adult's belief about which of the two locations held her toy. In experiments 1 and 2, the adult falsely believed that one of the locations held her toy. In experiment 3, the adult was ignorant about which of the two locations held her toy. In all cases, however, the toy had been removed from the locations and the locations contained instead materials which the adult wanted to avoid. In experiments 1 and 2, infants spontaneously and selectively informed the adult about the aversive material in the location the adult falsely believed to hold her toy. In contrast, in experiment 3, infants informed the ignorant adult about both locations equally. Results reveal that infants expected the adult to commit a specific action mistake when she held a false belief, but not when she was ignorant. Further, infants were motivated to intervene proactively. Findings reveal a predictive action-based usage of "theory-of-mind" skills at 18 months of age.

[Positional plagiocephaly in infants can be prevented]. / Lejringsbetingede skæve hoveder hos spædbørn kan forebygges.

The prevalence of positional plagiocephaly is increasing. A systematic database search (Cochrane, MEDLINE, Embase, Cinahl and PEDro), critical appraisal and systematic evaluation of the quality of 14 selected studies show that the following are certain risk factors for the development of positional plagiocephaly: supine sleeping position, positional preference, one-sided handling of the child, male sex, delayed motor development, reduced neck mobility, too little "tummy time", firstborn, multiple births and premature children. Recommendations for prevention are provided.