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The current study sought to determine the age at which children first engage in Level 1 visual perspective-taking, in which they understand that the content of what another person sees in a situation may sometimes differ from what they see. An adult entered the room searching for an object. One candidate object was out in the open, whereas another was visible for the child but behind an occluder from the adult's perspective. When asked to help the adult find the sought-for object, 24-month-old children, but not 18-month-old children, handed him the occluded object (whereas in a control condition they showed no preference for the occluded toy). We argue that the performance of the 24-month-olds requires Level 1 visual perspective-taking skills and that this is the youngest age at which these skills have been demonstrated. [ABSTRACT FROM AUTHOR]

The present work investigated the development of an explicit understanding of pretend play actions. Study 1 revealed a long décalage between earlier implicit understanding of pretence as an intentional activity and a later more explicit understanding. Study 2 was a training study. It tested for two factors - systematic pretence experience and explicit pretence discourse - that may be important in development from early implicit to later explicit pretence understanding. Two training groups of 3.5-year-old children received the same pretence experiences involving systematic contrasts between pretending, really performing and trying to perform actions. In the `explicit' group, these experiences were talked about with explicit `pretend to' and `pretend that' language. In the `implicit' group no such discourse was used, but only implicit discourse in talking about pretence versus real actions. The two training groups were compared with a control group that received functional play experience. After training, only the explicit group showed improvement in their explicit pretence understanding. In none of the groups was there any transfer to tasks tapping mental state understanding, false belief (FB) and appearance-reality, (A-R). The findings are discussed in the context of current theories about the developmental relations between pretence, discourse, and mental state understanding. [ABSTRACT FROM AUTHOR]

Purpose: This study explored the effect of frequency (number of presentations), and spacing (period between presentations) on verb learning in children with specific language impairment (SLI). Children learn words more efficiently when presentations are frequent and appropriately spaced, and this study investigated whether children with SLI likewise benefit. Given that these children demonstrate greater frequency dependence and rapid forgetting of recently acquired words, an investigation of frequency and spacing in this population is especially warranted. Method: Twenty-four children with SLI (mean age 5;6 [years;months]) and 24 language-matched control children (mean age 3;4) were taught novel verbs during play sessions. In a repeated measures design, 4 experimental conditions combined frequency (12 or 18 presentations) and spacing (all presentations in 1 session, or spread over 4 days). Comprehension and production probes were administered after the final session and 1 week later. Results: Although the children with SLI benefited significantly from frequent and widely spaced presentations, there were no significant effect in the control group. The language-impaired children showed rapid forgetting. Conclusions: The frequency and spacing of presentations crucially affect the verb learning of children with SLI. A training regimen characterized by appropriately spaced intervals and moderate repetition will optimally benefit lexical learning. [ABSTRACT FROM AUTHOR]

It is widely believed that what distinguishes the social cognition of humans from that of other animals is the belief–desire psychology of four–year–old children and adults (so–called theory of mind). We argue here that this is actually the second ontogenetic step in uniquely human social cognition. The first step is one year old children’s understanding of persons as intentional agents, which enables skills of cultural learning and shared intentionality. This initial step is ‘the real thing’ in the sense that it enables young children to participate in cultural activities using shared, perspectival symbols with a conventional/normative/reflective dimension—for example, linguistic communication and pretend play—thus inaugurating children’s understanding of things mental. Understanding beliefs and participating in collective intentionality at four years of age—enabling the comprehension of such things as money and marriage—results from several years of engagement with other persons in perspective–shifting and reflective discourse containing propositional attitude constructions. [ABSTRACT FROM AUTHOR]

In this work we studied the As redistribution in SiO2(70 nm)/Si(30 nm)/SiO2(70 nm) multilayer during postimplantation annealing. By Rutherford backscattering spectrometry and Z-contrast transmission electron microscopy we found an As accumulation at the Si/SiO2 interfaces and at the Si grain boundaries with no segregation of the As in the Si layer. Such an effect could be qualitatively in agreement with a model that assumes a traps distribution into the Si in the first 2–3 nm above the SiO2/Si interfaces and along the Si grain boundaries. In particular, the traps concentration at the Si/SiO2 interfaces was estimated in 1014 traps/cm2. [ABSTRACT FROM AUTHOR]

We report here a detailed study about the formation and self-organization of nanoscale structures during ion beam implantation at room temperature of 300 keV Ge+ in Ge as a function of the ion fluence in the range between 1×1014 to 4×1016 cm-2. “Microexplosions” characterize the morphology of the swelled material; a random cellular structure consisting of cells surrounded by amorphous Ge ripples has been observed and studied in details by combining atomic force microscopy, scanning electron microscopy, and transmission electron microscopy. [ABSTRACT FROM AUTHOR]

The article presents the abstract of the paper "Understanding of Communicative Gestures in Cooperative and Competitive Situations in Great Apes and Human Children," by E. Herrmann and M. Tomasello, to be presented at the 21st Congress of the International Primatological Society in Entebbe, Uganda from June 25-30, 2006.

This set of studies examined the ability of 3-year-olds to conceptualize multiple pretend identities with objects. Rather than relying on verbal response measures, as has been done in the past, children's creative and inferential pretend actions were used as indicators of their understanding. The common structure to all four studies was that children were confronted with one pretend scenario, moved to a second pretend scenario and then back again to the first. Children proficiently tailored their pretence to an object whose pretend identity changed between scenarios despite being less able to name each identity. Thus, using an inferential action methodology, these studies provide early and particularly convincing evidence that children can track the multiple pretend identities of objects. [ABSTRACT FROM AUTHOR]

The goal of the current study was to examine the contribution of three early social skills that may provide a foundation for cooperative performance in autism: (1) imitation, (2) joint attention, and (3) understanding of other people's intentions regarding actions on objects. Fourteen children with autistic disorder (AD) and 15 children with other developmental disabilities (DDs) matched on non-verbal developmental age (AD, mean 27.7, SD 9.8; DD, mean 33.4, SD 11.1) and verbal developmental age (AD, mean 21.5, SD 12.3; DD, mean 28.4, SD 11.0) participated in the study. Children with autism showed poorer performance on imitation and joint attention measures, but not on the intentionality task. Multiple regression analyses showed that imitation skills and joint attention contributed independently to cooperation, above and beyond the understanding of intentions of actions on objects. [ABSTRACT FROM AUTHOR]

Many mammalian species are highly social, creating intra-group competition for such things as food and mates. Recent research with nonhuman primates indicates that in competitive situations individuals know what other individuals can and cannot see, and they use this knowledge to their advantage in various ways. In the current study, we extended these findings to a non-primate species, the domestic goat, using the conspecific competition paradigm developed by Hare et al. (2000). Like chimpanzees and some other nonhuman primates, goats live in fission-fusion societies, form coalitions and alliances, and are known to reconcile after fights. In the current study, a dominant and a subordinate individual competed for food, but in some cases the subordinate could see things that the dominant could not. In the condition where dominants could only see one piece of food but subordinates could see both, subordinates' preferences depended on whether they received aggression from the dominant animal during the experiment. Subjects who received aggression preferred the hidden over the visible piece of food, whereas subjects who never received aggression significantly preferred the visible piece. By using this strategy, goats who had not received aggression got significantly more food than the other goats. Such complex social interactions may be supported by cognitive mechanisms similar to those of chimpanzees. We discuss these results in the context of current issues in mammalian cognition and socio-ecology. [ABSTRACT FROM AUTHOR]

Children's understanding of the grammatical categories of 'determiner' and 'adjective' was examined using 2 different methodologies. In Experiment 1, children heard novel nouns combined with either a or the. Few 2-year-olds, but nearly all 3- and 4-year-olds, subsequently produced the novel nouns with a different determiner from the modeled combination. Experiment 2 used a priming methodology. Children age 2, 3, 4, and 6 years repeated descriptions of pictures, before describing target pictures themselves. When the primes consisted of a varied determiner + noun, all age groups produced more determiner + noun descriptions. When the primes consisted of a determiner + adjective + noun, 2-year-olds showed no priming. Three- to 6-year-olds showed item-specific priming, but only 6-year-olds (and to a limited extent 4-year-olds) showed both item-specific and structural priming. These results suggest that children build an understanding of determiners and adjectives gradually, perhaps from individual lexical items, over a number of years, and that pragmatic correctness may be attained particularly late. [ABSTRACT FROM AUTHOR]

This study investigated children's understanding of others' intentions in a social learning context. Specifically, it investigated whether knowing an adult's prior intention before the adult gives a demonstration influences what children learn from the demonstration. In the five main experimental conditions, ninety-six 2-year-old children watched as an experimenter (E) pulled out a pin and opened the door of a box. Children in two No Prior Intention conditions saw this demonstration alone or paired with an irrelevant action. Children in three Prior Intention conditions knew what E was trying to do before the demonstration: they first saw E either attempt unsuccessfully to open the door, or visit and open several other containers, or they first saw that the door opened. Children opened the box themselves more often in each of these three conditions than in the two No Prior Intention conditions, even though children in all five conditions saw the exact same demonstration of how to open the box. [ABSTRACT FROM AUTHOR]

This article deals with looking for the best passive samplers among eleven plants diffused in the Mediterranean basin for the determination of polycyclic aromatic hydrocarbons in the atmosphere in substitution to the particulate matter sampling. The most recent research about biological passive samplers showed a quali-quantitative difference in pollutant sampling by different plants. Evergreen trees with long-lived leaves were selected in the urban area of Catania (Italy) and both samples (leaves and particulate matter) were extracted and purified by a two stage method before the analysis was performed by a GC/MS. Leaves and particulate matter were sampled in three different seasons (winter, spring and summer). PAHs concentrations found in the particulate matter and leaves were correlated. Some plants ( Olea europaea and Quercus ilex ) showed high values (r 2 > 0.85) of linear correlation coefficient in all seasons and are characterized by profiles similar to that of the particulate matter. Further, it has been observed that during the warmer seasons the total quantity of PAH adsorbed by the plants is greater but the fitting is better during winter. No difference was found by washing leaves with distilled water: this means that PAHs aren't deposited on the surface but are adsorbed in the lipidic layer of the leaves. [ABSTRACT FROM AUTHOR]

The article presents an abstract of the paper "Chimpanzees Know When They Need Help and Who Can Provide It," by A.P. Melis, B.A. Hare and M. Tomasello, to be presented at the 21st Congress of the International Primatological Society in Entebbe, Uganda on June 25-30, 2006.

The article presents an abstract of the paper "Chimpanzees know what others have seen," by J. Kaminski, J. Call and M. Tomasello, to be presented at the 21st Congress of the International Society of Primatological Society in Entebbe, Uganda on June 25-30, 2006.

The article presents the abstract of the paper "A Battery of Social Learning Tasks for All Species of Great Apes," by C. Tennie and colleagues to be presented at the 21st Congress of the International Primatological Society in Entebbe, Uganda from June 25-30, 2006.

We investigated young children's awareness of the context-relative rule structure of simple games. Two contexts were established in the form of spatial locations. Familiar objects were used in their conventional way at location 1, but acquired specific functions in a rule game at location 2. A third party then performed the conventional act at either of the two locations, constituting a mistake at location 2 (experimental condition), but appropriate at location 1 (control condition). Three-year-olds (but not 2-year-olds) systematically distinguished the two conditions, spontaneously intervening with normative protest against the third party act in the experimental, but not in the control condition. Young children thus understand context-specific rules even when the context marking is non-linguistic. These results are discussed in the broader context of the development of social cognition and cultural learning. [ABSTRACT FROM AUTHOR]

People often express excitement to each other when encountering an object that they have shared together previously in some special way. This study investigated whether 14-month-old infants know precisely what they have and have not shared in a special way (and with whom). In the experimental condition an adult and infant shared an object (the target) excitedly because it unexpectedly reappeared in several places. They then shared 2 other objects (the distractors) in a more normal fashion. Later, the adult reacted excitedly to a tray containing all 3 objects and then made an ambiguous request for the infant to hand "it" to her. There were 2 control conditions. In 1 of them, a different adult, who knew none of the 3 objects, made the ambiguous request. In the other control condition, the adult who made the request had previously experienced the objects only alone, while the infant looked on unengaged. Infants in the experimental condition chose the target object more often than the distractors and more often than they chose it in either control condition. These results demonstrate that 14-month-old infants can identify which one of a set of objects "we" - and not just I or you alone - have had a special experience with in the past. [ABSTRACT FROM AUTHOR]

We present the results from four studies, two corpora and two experimental, which suggest that English-and German-speaking children (3;1-4;9 years) use multiple constraints to process and produce object relative clauses. Our two corpora studies show that children produce object relatives that reflect the distributional and discourse regularities of the input. Specifically, the results show that when children produce object relatives they most often do so with (a) an inanimate head noun, and (b) a pronominal relative clause subject. Our experimental findings show that children use these constraints to process and produce this construction type. Moreover, when children were required to repeat the object relatives they most often use in naturalistic speech, the subject-object asymmetry in processing of relative clauses disappeared. We also report cross-linguistic differences in children's rate of acquisition which reflect properties of the input language. Overall, our results suggest that children are sensitive to the same constraints on relative clause processing as adults. [ABSTRACT FROM AUTHOR]

The present study examined English-speaking children's tendency to make argument structure overgeneralization errors (e.g., I disappeared it). Children were exposed to several English verbs of fixed transitivity (exclusively intransitive or exclusively transitive) and then asked questions that encouraged them to overgeneralize usage of the verbs. Seventy-two children (24 in each of three age groups: 3, 4/5, and 8 years of age) experienced four actions performed by puppets. Each action had two verbs of similar meaning associated with it in the context of the experimental action: one more familiar to young children and one less familiar. Children at all ages were more likely to overgeneralize usage of verbs that were less familiar to them, supporting the hypothesis that children's usage of verbs in particular construction types becomes entrenched over time. As children solidly learn the transitivity status of particular verbs, they become more reluctant to use those verbs in other argument structure constructions. [ABSTRACT FROM AUTHOR]

A nonverbal task of false belief understanding was given to 4- and 5-year-old children (N = 28) and to two species of great ape: chimpanzees and orangutans (N = 7). The task was embedded in a series of finding games in which an adult (the hider) hid a reward in one of two identical containers, and another adult (the communicator) observed the hiding process and attempted to help the participant by placing a marker on the container that she believed to hold the reward. An initial series of control trials ensured that participants were able to use the marker to locate the reward, follow the reward in both visible and invisible displacements, and ignore the marker when they knew it to be incorrect. In the crucial false belief trials, the communicator watched the hiding process and then left the area, at which time the hider switched the locations of the containers. When the communicator returned, she marked the container at the location where she had seen the reward hidden, which was incorrect. The hider then gave the subject the opportunity to find the sticker. Successful performance required participants to reason as follows: the communicator placed the marker where she saw the reward hidden; the container that was at that location is now at the other location; so the reward is at the other location. Children were also given a verbal false belief task in the context of this same hiding game. The two main results of the study were: (1) children's performance on the verbal and nonverbal false belief tasks were highly correlated (and both fit very closely with age norms from previous studies), and (2) no ape succeeded in the nonverbal false belief task even though they succeeded in all of the control trials indicating mastery of the general task demands. [ABSTRACT FROM AUTHOR]

The article presents an abstract of the paper "Zoo living orangutans (Pongo pygmaeus) inform a human for selfish reasons but not to help altruistically," by F. Haimerl and colleagues, to be presented at the 21st Congress of the International Society of Primatological Society in Entebbe, Uganda on June 25-30, 2006.

The article presents an abstract of the paper "What's in it for me? Self-regard precludes altruism and spite in chimpanzees," by K. Jensen and colleagues, to be presented at the 21st Congress of the International Primatological Society at the Imperial Resort Beach Hotel in Entebbe, Uganda, from June 25-30, 2006.