The SNARC effect does not imply a mental number line

In this study, we directly contrast two approaches that have been proposed to explain the SNARC effect. The traditional direct mapping account suggests that a direct association exists between the position of a number on the mental number line and the location of the response. On the other hand, accounts are considered that propose an intermediate step in which numbers are categorized as either small or large between the number magnitude and the response representations. In a magnitude comparison task, we departed from the usual bimanual left/right response dimension and instead introduced the unimanual close/far dimension. A spatial-numerical association was observed: small numbers were associated with a close response, while large numbers were associated with a far response, regardless of the movement direction (left/right). We discuss why these results cannot be explained by assuming a direct mapping from the representation of numbers on a mental number line to response locations and discuss how the results can be explained by the alternative accounts.     

Evidence for a non-linguistic distinction between singular and plural sets in rhesus monkeys

Set representations are explicitly expressed in natural language. For example, many languages distinguish between sets and subsets (all vs. some), as well as between singular and plural sets (a cat vs. some cats). Three experiments explored the hypothesis that these representations are language specific, and thus absent from the conceptual resources of non-linguistic animals. We found that rhesus monkeys spontaneously discriminate sets based on a conceptual singular-plural distinction. Under conditions that do not elicit comparisons based on approximate magnitudes or one-to-one correspondence, rhesus monkeys distinguished between singular and plural sets (1 vs. 2 and 1 vs. 5), but not between two plural sets (2 vs. 3, 2 vs. 4, and 2 vs. 5). These results suggest that set-relational distinctions are not a privileged part of natural language, and may have evolved in non-linguistic species to support domain general quantitative computations.     

Mandarin learners use syntactic bootstrapping in verb acquisition

Mandarin Chinese allows pervasive ellipsis of noun arguments (NPs) in discourse, which casts doubt concerning child learners' use of syntax in verb learning. This study investigated whether Mandarin learning children would nonetheless extend verb meanings based on the number of NPs in sentences. Forty-one Mandarin-speaking two- and three-year-olds enacted sentences with familiar motion verbs. The presence of an extra postverbal NP led the toddlers to extend causative meanings to intransitive verbs, and the absence of a postverbal NP led them to extend noncausative meanings to transitive verbs. The effects of adding or subtracting an NP were statistically indistinguishable. Thus, the number of NPs in a sentence appears to play a role in verb learning in Mandarin Chinese.     

Visuospatial priming of the mental number line

It has been argued that numbers are spatially organized along a "mental number line" that facilitates left-hand responses to small numbers, and right-hand responses to large numbers. We hypothesized that whenever the representations of visual and numerical space are concurrently activated, interactions can occur between them, before response selection. A spatial prime is processed faster than a numerical target, and consistent with our hypothesis, we found that such a spatial prime affects non-spatial, verbal responses more when the prime follows a numerical target (backward priming) then when it precedes it (forward priming). This finding emerged both in a number-comparison and a parity judgment task, and cannot be ascribed to a "Spatial-Numerical Association of Response Codes" (SNARC). Contrary to some earlier claims, we therefore conclude that visuospatial-numerical interactions do occur, even before response selection.     

Anaphoric agreement violation: an ERP analysis of its interpretation

In the present study we analyzed the processing of grammatically anomalous sentences like "The famous dancer were nervously preparing herself/themselves to face the crowd.", which contains two anomalies, one early and one late. We investigated how processing of the later anomaly (at the pronoun 'herself' or 'themselves') was affected by the processing of the early anomaly (at 'were'). We considered two processing scenarios involving the first anomaly: (1) The representation of the subject-verb number agreement error at the first verb is coerced to match the verb, rendering 'herself' anomalous; (2) The representation of the subject-verb agreement error is coerced to match the subject noun, rendering 'themselves' anomalous. Our dependent measure was event-related scalp potentials (ERPs). When the pronoun disagreed with the verb (and agreed with the subject), a P600 was recorded, while the opposite condition elicited no reliable effect. Our data suggest that interpretation of reflexive pronouns involves the reactivation of multiple lexical items, verbs included.     

Children's equivalence judgments: Crossmapping effects

Preschoolers made numerical comparisons between sets with varying degrees of shared surface similarity. When surface similarity was pitted against numerical equivalence (i.e., crossmapping), children made fewer number matches than when surface similarity was neutral (i.e, all sets contained the same objects). Only children who understood the number words for the target sets performed above chance in the crossmapping condition. These findings are consistent with previous research on children's non-numerical comparisons (e.g., [Rattermann, M. J., & Gentner, D. (1998). The effect of language on similarity: The use of relational labels improves young children's performance in a mapping task. In K. Holyoak, D. Gentner, & B. Kokinov (Eds.), Advances in analogy research: Integration of theory and data from cognitive, computational, and neural sciences (pp. 274–282). Sofia: New Bulgarian University; Smith, L. B. (1993). The concept of same. In H. W. Reese (Ed.), Advances in child development and behavior, Vol. 24 (pp. 215–252). New York: Academic Press]) and suggest that the same mechanisms may underlie numerical development.     

Response patterns of young children from two contrasting SES contexts to different numerical tasks with numbers 1–5

This study contributes to a multifaceted picture of young children’s emergent number knowledge by focusing on the variety of ways in which children express and use quantitative information. The authors’ aims are to (a) explore the extent to which quantifying collections 1–5 and using that information pose different levels of difficulty to children from 33 to 47?months old, (b) identify intra- and intertask response patterns, and (c) analyze the influence of socioeconomic status and age on these response patterns. Sixty-six children from two contrasting socioeconomic status groups (very low and middle) were asked to solve tasks with 1–5 elements in the context of a game. Using quantitative information turned out to be more complex than quantification. Intra- and intertask response patterns showed that children gradually come to understand the first five numerical values according to the numerical sequence in a much less strict way than that proposed by the cardinal-knowers model that posits that children progress in an orderly way in their number knowledge. Children in different ages and socioeconomic status groups were found to be more similar to each other when the whole arc of responses provided was considered than when solely correct performance was measured.     

Language effects in magnitude comparison: small, but not irrelevant

It is assumed that number magnitude comparison is performed by assessing magnitude representation on a single analog mental number line. However, we have observed a unit-decade-compatibility effect in German which is inconsistent with this assumption (Nuerk, Weger, & Willmes, 2001). Incompatible magnitude comparisons in which decade and unit comparisons lead to different responses (e.g., 37_52 for which 3<5, but 7>2) are slower and less accurately responded to than compatible trials in which decade and unit comparisons lead to the same response (e.g., 42_57, for which 4<5 and 2<7). As overall distance was held constant, a single holistic magnitude representation could not account for this compatibility effect. However, because of the inversion property of the corresponding German two-digit number words ("einundzwanzig" ), the language-generality of the effect is questionable. We have therefore examined the compatibility effect with native English speakers. We were able to replicate the compatibility effect using Arabic notation. Thus, the compatibility effect is not language-specific. However, in cross-linguistic analyses language-specific modulations were observed not only for number words but also for Arabic numbers. The constraints imposed on current models by the verbal mediation of Arabic number comparison are discussed.     

数字表征的表象赋义效应:来自数字线估计任务的证据

已有研究中数字线估计任务几乎都使用纯数字。本研究以二到六年级儿童为被试,采用纯数字任务和赋义数字任务来探索赋义表象对数字表征形式的影响。结果表明,对0~1000的数字赋义后,对数模型的解释力上升,而线性模型的解释力下降;表象大小对于赋义数字的估计影响显著,大表象赋义提高了对数模型解释力而降低了数字估计的准确性,小表象的影响比较微弱。