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Humans and other animals are able to perceive and represent a number of objects present in a scene, a core cognitive ability thought to underlie the development of mathematics. However, the perceptual mechanisms that underpin this capacity remain poorly understood. Here, we show that our visual sense of number derives from a visual system designed to efficiently encode the location of objects in scenes. Using a mathematical model, we demonstrate that an efficient but information-limited encoding of objects' locations can explain many key aspects of number psychophysics, including subitizing, Weber's law, underestimation, and effects of exposure time. In two experiments (N = 100 each), we find that this model of visual encoding captures human performance in both a change-localization task and a number estimation task. In a third experiment (N = 100), we find that individual differences in change-localization performance are highly predictive of differences in number estimation, both in terms of overall performance and inferred model parameters, with participants having numerically indistinguishable inferred information capacities across tasks. Our results therefore indicate that key psychophysical features of numerical cognition do not arise from separate modules or capacities specific to number, but rather as by-products of lower level constraints on perception. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: We assessed associations between child stunting, recovery, and faltering with schooling and human capital skills in a native Amazonian society of horticulturalists‐foragers (Tsimane'). Methods: We used cross‐sectional data (2008) from 1262 children aged 6 to 16 years in 53 villages to assess contemporaneous associations between three height categories: stunted (height‐for‐age Z score, HAZ<–2), moderately stunted (–2 ≤ HAZ≤–1), and nonstunted (HAZ>–1), and three categories of human capital: completed grades of schooling, test‐based academic skills (math, reading, writing), and local plant knowledge. We used annual longitudinal data (2002–2010) from all children (n = 853) in 13 villages to estimate the association between changes in height categories between the first and last years of measure and schooling and academic skills. Results: Stunting was associated with 0.4 fewer completed grades of schooling (∼24% less) and with 13–15% lower probability of showing any writing or math skills. Moderate stunting was associated with ∼20% lower scores in local plant knowledge and 9% lower probability of showing writing skills, but was not associated with schooling or math and writing skills. Compared with nonstunted children, children who became stunted had 18–21% and 15–21% lower probabilities of showing math and writing skills, and stunted children had 0.4 fewer completed grades of schooling. Stunted children who recovered showed human capital outcomes that were indistinguishable from nonstunted children. Conclusions: The results confirm adverse associations between child stunting and human capital skills. Predictors of growth recovery and faltering can affect human capital outcomes, even in a remote, economically self‐sufficient society. [ABSTRACT FROM AUTHOR]

Although the mapping between form and meaning is often regarded as arbitrary, there are in fact well-known constraints on words which are the result of functional pressures associated with language use and its acquisition. In particular, languages have been shown to encode meaning distinctions in their sound properties, which may be important for language learning. Here, we investigate the relationship between semantic distance and phonological distance in the large-scale structure of the lexicon. We show evidence in 100 languages from a diverse array of language families that more semantically similar word pairs are also more phonologically similar. This suggests that there is an important statistical trend for lexicons to have semantically similar words be phonologically similar as well, possibly for functional reasons associated with language learning. [ABSTRACT FROM AUTHOR]

Hackl, Koster-Hale & Varvoutis (2012; HKV) provide data that suggest that in a null context, antecedent-contained-deletion (ACD) relative clause structures modifying a quantified object noun phrase (NP; such as every doctor) are easier to process than those modifying a definite object NP (such as the doctor). HKV argue that this pattern of results supports a 'quantifier-raising' (QR) analysis of both ACD structures and quantified NPs in object position: under the account they advocate, both ACD resolution and quantified NPs in object position require movement of the object NP to a higher syntactic position. The processing advantage for quantified object NPs in ACD is hypothesized to derive from the fact that--at the point where ACD resolution must take place--the quantified NP has already undergone QR whereas this is not the case for definite NPs. Although in other work it is shown that HKV's reading time analyses are flawed, such that the critical effects are not significant (Gibson et al. submitted), the effect in HKV's acceptability rating is robust. But HKV's interpretation is problematic. We present five experiments that provide evidence for an alternative, pragmatic, explanation for HKV's observation. In particular, we argue that the low acceptability of the the / ACD condition is largely due to a strong pressure in the null context to use a competing form, by adding also or same. This pressure does not exist with quantified NPs either because the competing form is absent (*every same) or because the addition of also actually degrades the sentence. In support of this interpretation, we show that the difference between the the / ACD and every / ACD conditions (a) persists even when the relative clause contains no ellipsis and thus nothing is forcing QR; (b) disappears when either also or same is added; and (c) disappears in supportive contexts. Together, these findings show that HKV's QR hypothesis should be rejected in favor of a pragmatic account. [ABSTRACT FROM AUTHOR]

Absolute linguistic universals are often justified by cross-linguistic analysis: If all observed languages exhibit a property, the property is taken to be a likely universal, perhaps specified in the cognitive or linguistic systems of language learners and users. In many cases, these patterns are then taken to motivate linguistic theory. Here, we show that cross-linguistic analysis will very rarely be able to statistically justify absolute, inviolable patterns in language. We formalize two statistical methods-frequentist and Bayesian-and show that in both it is possible to find strict linguistic universals, but that the numbers of independent languages necessary to do so is generally unachievable. This suggests that methods other than typological statistics are necessary to establish absolute properties of human language, and thus that many of the purported universals in linguistics have not received sufficient empirical justification. [ABSTRACT FROM AUTHOR]

The scope of human learning and development poses a radical challenge for cognitive science. We propose that developmental theories can address this challenge by adopting perspectives from computer science. Many of our best models treat learning as analogous to computer programming because symbolic programs provide the most compelling account of sophisticated mental representations. We specifically propose that children's learning is analogous to a particular style of programming called hacking, making code better along many dimensions through an open-ended set of goals and activities. By contrast to existing theories, which depend primarily on local search and simple metrics, this view highlights the many features of good mental representations and the multiple complementary processes children use to create them. • Programs provide our best general-purpose representations for human knowledge, inference, and planning; human learning is thus increasingly modeled as program induction, learning programs from data. • Many formal models of learning as program induction reduce to a stochastic search for concise descriptions of data. Actual human programmers and learners are significantly more complex, using many processes to optimize complex and frequently changing objectives. • The goals and activities of hacking, making code better along many dimensions through an open-ended and internally motivated set of goals and activities, are helping to inspire better models of human learning and cognitive development. [ABSTRACT FROM AUTHOR]

It is now a common practice to compare models of human language processing by comparing how well they predict behavioral and neural measures of processing difficulty, such as reading times, on corpora of rich naturalistic linguistic materials. However, many of these corpora, which are based on naturally-occurring text, do not contain many of the low-frequency syntactic constructions that are often required to distinguish between processing theories. Here we describe a new corpus consisting of English texts edited to contain many low-frequency syntactic constructions while still sounding fluent to native speakers. The corpus is annotated with hand-corrected Penn Treebank-style parse trees and includes self-paced reading time data and aligned audio recordings. We give an overview of the content of the corpus, review recent work using the corpus, and release the data. [ABSTRACT FROM AUTHOR]

Background: Seasons affect many social, economic, and biological outcomes, particularly in low-resource settings, and some studies suggest that birth season affects child growth. Aim: To study a predictor of stunting that has received limited attention: birth season. Subjects and methods: This study uses cross-sectional data collected during 2008 in a low-resource society of horticulturists-foragers in the Bolivian Amazon, Tsimane’. It estimates the associations between birth months and height-for-age Z-scores (HAZ) for 562 girls and 546 boys separately, from birth until age 11 years or pre-puberty, which in this society occurs ∼13-14 years. Results: Children born during the rainy season (February-May) were shorter, while children born during the end of the dry season and the start of the rainy season (August-November) were taller, both compared with their age-sex peers born during the rest of the year. The correlations of birth season with HAZ were stronger for boys than for girls. Controlling for birth season, there is some evidence of eventual partial catch-up growth, with the HAZ of girls or boys worsening until ∼ age 4-5 years, but improving thereafter. By age 6 years, many girls and boys had ceased to be stunted, irrespective of birth season. Conclusion: The results suggest that redressing stunting will require attention to conditions in utero, infancy and late childhood. [ABSTRACT FROM AUTHOR]

Recent evidence suggests that cognitive pressures associated with language acquisition and use could affect the organization of the lexicon. On one hand, consistent with noisy channel models of language (e.g., Levy, 2008), the phonological distance between wordforms should be maximized to avoid perceptual confusability (a pressure for dispersion). On the other hand, a lexicon with high phonological regularity would be simpler to learn, remember and produce (e.g., Monaghan et al., 2011) (a pressure for clumpiness). Here we investigate wordform similarity in the lexicon, using measures of word distance (e.g., phonological neighborhood density) to ask whether there is evidence for dispersion or clumpiness of wordforms in the lexicon. We develop a novel method to compare lexicons to phonotactically-controlled baselines that provide a null hypothesis for how clumpy or sparse wordforms would be as the result of only phonotactics. Results for four languages, Dutch, English, German and French, show that the space of monomorphemic wordforms is clumpier than what would be expected by the best chance model according to a wide variety of measures: minimal pairs, average Levenshtein distance and several network properties. This suggests a fundamental drive for regularity in the lexicon that conflicts with the pressure for words to be as phonologically distinct as possible. [ABSTRACT FROM AUTHOR]