How do representations of space inform our perception of time? In language, spatial vocabulary is frequently used to describe temporal concepts, and spatial information biases temporal perception even in non-verbal tasks. In contrast, temporal information typically exerts little, if any, influence on the perception of spatial extent. Here, we used spatial and temporal reproduction tasks, both with and without verbal and spatial dual tasks, to investigate the mechanism underlying the asymmetric relation between space and time. Specifically, we tested whether the asymmetric interference between spatial and temporal stimulus attributes arises from interference in verbal or visuospatial working memory. We found that loading visuospatial working memory, but not verbal working memory, eliminated the asymmetric pattern of interference. This suggests that the interference between spatial and temporal representations arises due to processing constraints in visuospatial working memory. These findings are discussed in terms of the load theory of attention and the relative automaticity with which spatial and temporal information is processed.

Prior work demonstrates that humans represent the approximate number of items across multiple sets simultaneously. Here we investigated whether adults can approximately divide multiple distinct overlapping sets simultaneously. Participants viewed arrays with dots of one to four colors (potential dividends) and a non-symbolic divisor of 2-4. Participants then estimated the quotient of the division operation. On each trial a cue indicated whether to divide over the superset of all dots or a color subset. The cue was presented before or after the brief presentation of the dividend array. We found that the capacity to divide over a pre-selected subset was not affected by set size. By comparing the estimation error between the cue-before and cue-after conditions, we determined that a substantial proportion of participants can approximately divide three ensembles simultaneously (two subsets plus the superset). These findings demonstrate the computational efficiency and possible utility of ensemble representations.

Visual number adaption is a widely accepted phenomenon. This paper advances an alternative explanation for putative cases of the phenomenon. We propose that such cases may simply reflect observers adapting to the items in perceived displays, rather than their numerical quantity. Three experiments motivate consideration of this novel proposal and call into question the evidential basis for received formulations of the number adaptation hypothesis.

The approximate number system (ANS) is frequentlyconsidered to be a foundation for the acquisition of uniquelyhuman symbolic numerical capabilities. However, themechanism by which the ANS influences symbolic numberrepresentations and mathematical thought remains poorlyunderstood. Here, we tested the relation between ANS acuity,cardinal number knowledge, approximate arithmetic, andsymbolic math achievement in a one-year longitudinalinvestigation of preschoolers’ early math abilities. Our resultssuggest that cardinal number knowledge is an intermediaryfactor in the relation between ANS acuity and symbolic mathachievement. Furthermore, approximate arithmeticperformance contributes unique variance to math achievementthat is not accounted for by ANS acuity. These findingssuggest that there are multiple routes by which the ANSinfluences math achievement. Therefore, interventionstargeting both the precision and manipulability of the ANSmay prove to be more beneficial for improving mathematicalreasoning compared to interventions targeting only one ofthese factors.

Cognition presents evolutionary research with one of its greatest challenges. Cognitive evolution has been explained at the proximate level by shifts in absolute and relative brain volume and at the ultimate level by differences in social and dietary complexity. However, no study has integrated the experimental and phylogenetic approach at the scale required to rigorously test these explanations. Instead, previous research has largely relied on various measures of brain size as proxies for cognitive abilities. We experimentally evaluated these major evolutionary explanations by quantitatively comparing the cognitive performance of 567 individuals representing 36 species on two problem-solving tasks measuring self-control. Phylogenetic analysis revealed that absolute brain volume best predicted performance across species and accounted for considerably more variance than brain volume controlling for body mass. This result corroborates recent advances in evolutionary neurobiology and illustrates the cognitive consequences of cortical reorganization through increases in brain volume. Within primates, dietary breadth but not social group size was a strong predictor of species differences in self-control. Our results implicate robust evolutionary relationships between dietary breadth, absolute brain volume, and self-control. These findings provide a significant first step toward quantifying the primate cognitive phenome and explaining the process of cognitive evolution.