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A single factor (i.e., general intelligence) can account for much of an individuals' performance across a wide variety of cognitive tests. However, despite this factor's robustness, the underlying process is still a matter of debate. To address this question, we developed a novel battery of learning tasks to assess the general learning abilities (GLAs) of mice. Using this battery, we previously reported a strong relationship between GLA and a task designed to tax working memory capacity (i.e., resistance to competing demands). Here we further explored this relationship by investigating which aspects of working memory (storage or processing) best predict GLAs in mice. We found that a component of working memory, selective attention, correlated with GLA comparably to working memory capacity. However, this relationship was not found for two other components of working memory, short-term memory capacity and duration. These results provide further evidence that variations in aspects of working memory and executive functions covary with general cognitive abilities.

Summary In humans, aspects of working memory capacity (i.e., resistance to interference or selective attention) correlate strongly with measures indicative of general intelligence [1–7], and likewise, the efficacy of working memory capacity and its related process, selective attention, are each strongly predictive of the aggregate performance of individual mice in cognitive test batteries [8,9]. Since by its nature, working memory is taxed during most cognitive tasks, it has been suggested that the efficacy of working memory may have a causal influence on individuals’ performance on common tests of “intelligence” [10,11]. Despite the attention that this possibility has received, supporting evidence based on studies of humans has been largely correlational in nature (but see [12]). Here, genetically heterogeneous mice were assessed on a battery of five learning tasks. Animals’ aggregate performance across the five tasks was used to estimate their general cognitive abilities, a trait that is in some respects analogous to intelligence [13,14]. In two experiments, we demonstrate that repetitive working memory training (concurrent performance in two eight-choice mazes) promoted an increase in selective attention and had a commensurately positive effect on the animals’ aggregate performance on a battery of five learning tasks. The enhancement of general cognitive performance by working memory exercise was attenuated if the nominal selective attention demands of that working memory training were reduced. In total, these results provide initial evidence that the efficacy of working memory capacity and selective attention are causally related to an animal’s general cognitive performance, and suggest behavioral strategies to promote those abilities. Furthermore, these results suggest a conservation of the processes that regulate general cognitive performance in humans and infrahuman animals.

It has been established that both domain-specific (e.g. spatial) as well as domain-general (general intelligence) factors influence human cognition. However, the separation of these processes has rarely been attempted in studies using laboratory animals. Previously, we have found that the performances of outbred mice across a wide range of learning tasks correlate in such a way that a single factor can explain 30-44% of the variance between animals. This general learning factor is in some ways qualitatively and quantitatively analogous to general intelligence in humans. The complete structure of cognition in mice, however, has not been explored due to the limited sample sizes of our previous analyses. Here we report a combined analysis from 241 CD-1 mice tested in five primary learning tasks, and a subset of mice tested in two additional learning tasks. At least two (possibly three) of the seven learning tasks placed explicit demands on spatial and/or hippocampusdependent processing abilities. Consistent with previous findings, we report a robust general factor influencing learning in mice that accounted for 38% of the variance across tasks. In addition, a domain-specific factor was found to account for performance on that subset of tasks that shared a dependence on hippocampal and/or spatial processing. These results provide further evidence for a general learning/cognitive factor in genetically heterogeneous mice. Furthermore (and similar to human cognitive performance), these results suggest a hierarchical structure to cognitive processes in this genetically heterogeneous species. KeywordsIntelligence; Working Memory; Learning; Cognitive Abilities; Hippocampus; Spatial Learning; Mice For much of the history of animal studies of learning and memory, research has focused primarily on the processes and mechanisms that regulate single domains of learning (e.g., spatial abilities or Pavlovian conditioning). While this tactic has been successful in delineating the neuroanatomical substrates of certain forms of learning (e.g., Christian & Thompson;2003;Eichenbaum, 2000;Phelps & LeDoux, 2005;White & McDonald, 2002) it has left unexplored those aspects of learning that are common across all domains. Conversely, studies of humans have focused extensively on the mechanisms that underlie general influences that impinge on all cognitive abilities (i.e., general intelligence). However, such studies are constrained by certain practical and ethical considerations that do not similarly limit studies of Corresponding Author: Louis D. Matzel, Department of Psychology, Rutgers University, Piscataway, NJ 08854, Email: Matzel@rci.rutgers.edu, Phone: 732/445-5940, Fax: 732/445-2263. Publisher's Disclaimer: This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final citable form. Please note tha...