The Comparative Analysis of Intelligence.

The study of intelligence in humans has been ongoing for over 100 years, including the underlying structure, predictive validity, related cognitive measures, and source of differences. One of the key findings in intelligence research is the uniform positive correlations among cognitive tasks. This has been replicated with every cognitive test battery in humans. Nevertheless, many other aspects of intelligence research have revealed contradictory lines of evidence. Recently, cognitive test batteries have been developed for animals to examine similarities to humans in cognitive structure. The results are inconsistent, but there is evidence for some similarities. This article reviews the way intelligence and related cognitive abilities are assessed in humans and animals and suggests a different way of devising test batteries for maximizing between-species comparisons. Public Significance Statement: This review highlights the difficulty in understanding why different cognitive abilities are related to each other in human and nonhuman animals. Cognitive abilities are related in similar ways across species, but test batteries should be refined to strengthen these findings and increase translational significance. [ABSTRACT FROM AUTHOR]