Transmitting pro‐environmental behaviours to the next generation: A comparison between Germany and Japan

The present study examined the processes by which children acquire pro‐environmental behaviours in different cultures. Our focus was on parental influence. Several studies have been conducted on adults' environmental behaviours; however, we know little about how children's environmental attitudes and behaviours are formed. We conducted a questionnaire survey with elementary school children and one of their parents in Germany and Japan. Two hundred and twenty‐one pairs participated in Germany and 365 in Japan. The results of structural equation modelling showed that parents' behaviours affected children's environmental behaviours directly and also via the subjective norm (the children's experienced expectations of their parents). A comparison of the two countries revealed that hypothesized cultural differences between the impact of personal norms and subjective norms were clearer for adults. The results also showed that the effects of subjective norms were stronger for children, indicating that children are more likely to be influenced by expectations of others. The results of the study suggest that for promoting children's environmental behaviours, showing the behaviours in daily life would be most effective.     

Mental representations of magnitude and order: A dissociation by sensorimotor learning

Numbers and spatially directed actions share cognitive representations. This assertion is derived from studies that have demonstrated that the processing of small- and large-magnitude numbers facilitates motor behaviors that are directed to the left and right, respectively. However, little is known about the role of sensorimotor learning for such number–action associations. In this study, we show that sensorimotor learning in a serial reaction-time task can modify the associations between number magnitudes and spatially directed movements. Experiments 1 and 3 revealed that this effect is present only for the learned sequence and does not transfer to a novel unpracticed sequence. Experiments 2 and 4 showed that the modification of stimulus–action associations by sensorimotor learning does not occur for other sets of ordered stimuli such as letters of the alphabet. These results strongly suggest that numbers and actions share a common magnitude representation that differs from the common order representation shared by letters and spatially directed actions. Only the magnitude representation, but not the order representation, can be modified episodically by sensorimotor learning.     

Reasoning about knowledge: Children’s evaluations of generality and verifiability

In a series of experiments, we examined 3- to 8-year-old children’s (N = 223) and adults’ (N = 32) use of two properties of testimony to estimate a speaker’s knowledge: generality and verifiability. Participants were presented with a “Generic speaker” who made a series of 4 general claims about “pangolins” (a novel animal kind), and a “Specific speaker” who made a series of 4 specific claims about “this pangolin” as an individual. To investigate the role of verifiability, we systematically varied whether the claim referred to a perceptually-obvious feature visible in a picture (e.g., “has a pointy nose”) or a non-evident feature that was not visible (e.g., “sleeps in a hollow tree”). Three main findings emerged: (1) young children showed a pronounced reliance on verifiability that decreased with age. Three-year-old children were especially prone to credit knowledge to speakers who made verifiable claims, whereas 7- to 8-year-olds and adults credited knowledge to generic speakers regardless of whether the claims were verifiable; (2) children’s attributions of knowledge to generic speakers was not detectable until age 5, and only when those claims were also verifiable; (3) children often generalized speakers’ knowledge outside of the pangolin domain, indicating a belief that a person’s knowledge about pangolins likely extends to new facts. Findings indicate that young children may be inclined to doubt speakers who make claims they cannot verify themselves, as well as a developmentally increasing appreciation for speakers who make general claims.     

Why is number word learning hard? Evidence from bilingual learners

Young children typically take between 18 months and 2 years to learn the meanings of number words. In the present study, we investigated this developmental trajectory in bilingual preschoolers to examine the relative contributions of two factors in number word learning: (1) the construction of numerical concepts, and (2) the mapping of language specific words onto these concepts. We found that children learn the meanings of small number words (i.e., one, two, and three) independently in each language, indicating that observed delays in learning these words are attributable to difficulties in mapping words to concepts. In contrast, children generally learned to accurately count larger sets (i.e., five or greater) simultaneously in their two languages, suggesting that the difficulty in learning to count is not tied to a specific language. We also replicated previous studies that found that children learn the counting procedure before they learn its logic – i.e., that for any natural number, n, the successor of n in the count list denotes the cardinality n + 1. Consistent with past studies, we found that children’s knowledge of successors is first acquired incrementally. In bilinguals, we found that this knowledge exhibits item-specific transfer between languages, suggesting that the logic of the positive integers may not be stored in a language-specific format. We conclude that delays in learning the meanings of small number words are mainly due to language-specific processes of mapping words to concepts, whereas the logic and procedures of counting appear to be learned in a format that is independent of a particular language and thus transfers rapidly from one language to the other in development.     

Revise and resubmit: How real-time parsing limitations influence grammar acquisition

We present the results from a three-day artificial language learning study on adults. The study examined whether sentence-parsing limitations, in particular, difficulties revising initial syntactic/semantic commitments during comprehension, shape learners’ ability to acquire a language. Findings show that both comprehension and production of morphology pertaining to sentence argument structure are delayed when this morphology consistently appears at the end, rather than at the beginning, of sentences in otherwise identical grammatical systems. This suggests that real-time processing constraints impact acquisition; morphological cues that tend to guide linguistic analyses are easier to learn than cues that revise these analyses. Parallel performance in production and comprehension indicates that parsing constraints affect grammatical acquisition, not just real-time commitments. Properties of the linguistic system (e.g., ordering of cues within a sentence) interact with the properties of the cognitive system (cognitive control and conflict-resolution abilities) and together affect language acquisition.     

Identifying expectations about the strength of causal relationships

When we try to identify causal relationships, how strong do we expect that relationship to be? Bayesian models of causal induction rely on assumptions regarding people’s a priori beliefs about causal systems, with recent research focusing on people’s expectations about the strength of causes. These expectations are expressed in terms of prior probability distributions. While proposals about the form of such prior distributions have been made previously, many different distributions are possible, making it difficult to test such proposals exhaustively. In Experiment 1 we used iterated learning—a method in which participants make inferences about data generated based on their own responses in previous trials—to estimate participants’ prior beliefs about the strengths of causes. This method produced estimated prior distributions that were quite different from those previously proposed in the literature. Experiment 2 collected a large set of human judgments on the strength of causal relationships to be used as a benchmark for evaluating different models, using stimuli that cover a wider and more systematic set of contingencies than previous research. Using these judgments, we evaluated the predictions of various Bayesian models. The Bayesian model with priors estimated via iterated learning compared favorably against the others. Experiment 3 estimated participants’ prior beliefs concerning different causal systems, revealing key similarities in their expectations across diverse scenarios.     

The role of eye movements in motor sequence learning

An experiment that utilized a 16-element movement sequence was designed to determine the impact of eye movements on sequence learning. The participants were randomly assigned to two experimental groups: a group that was permitted to use eye movements (FREE) and a second group (FIX) that was instructed to fixate on a marker during acquisition (ACQ). A retention test (RET) was designed to provide a measure of learning, and two transfer tests were designed to determine the extent to which eye movements influenced sequence learning. The results demonstrated that both groups decreased the response time to produce the sequence, but the participants in the FREE group performed the sequence more quickly than participants of the FIX group during the ACQ, RET and the two transfer tests. Furthermore, continuous visual control of response execution was reduced over the course of learning. The results of the transfer tests indicated that oculomotor information regarding the sequence can be stored in memory and enhances response production.     

Evidence of a role for multiple memory systems in behavioral extinction

The acquisition of learned behavior involves multiple memory systems, and hippocampal system damage impairs cognitive learning while leaving stimulus-response habit learning intact. In view of evidence that extinction also involves new learning, the present experiments examined whether multiple memory systems theory may be applicable to the neural bases of extinction. Adult Long-Evans rats were trained to run in a straight-alley maze for food reward. Twenty-four hours later, rats matched for runway latencies during acquisition received extinction training. In a response extinction condition conducive to habit learning, rats performed a runway approach response to an empty food cup. In a latent extinction condition conducive to cognitive learning, rats were placed at an empty food cup without performing a runway approach response. Prior to daily extinction training, neural activity of the dorsal hippocampus was reversibly inactivated via infusion of bupivacaine (0.75%, 0.5 microl/side). Control rats receiving saline infusions displayed extinction behavior in both the response and latent training conditions. In contrast, rats receiving bupivacaine extinguished normally in the response condition, but did not display latent extinction. The findings (1) confirm that learning underlying extinction of the same overt behavior can occur with or without explicit performance of the previously acquired response, (2) indicate that extinction learning produced by response and latent training procedures can be neuroanatomically dissociated, and (3) suggest that similarly to initial task acquisition, the hippocampus may critically mediate extinction in situations requiring the use of cognitive learning, such as when performance of a previously acquired response habit is prevented.