Individual differences and a spatial learning factor in two strains of mice (Mus musculus).

Abstract

Current theoretical approaches to animal intelligence either in the form of adaptive specializations or general processes make no explicit predictions nor do they provide substantial evidence concerning individual differences in problem solving. Two strains of mice (Mus musculus) were run through a battery of water escape tasks consisting of 4 spatial learning tasks, a visual discrimination task, and an activity control. The 2 strains were the second filial generation (F 2) from a cross between C57BL/6 and DBA/2Js inbred strains and a CD-I outbred strain. Results indicated positive correlations across all learning tasks in both strains for latency and error measures. Factor analysis revealed a significant first factor for these measures in both strains. These results suggest that at least some spatial and visual tasks in mice under this motivational condition share common properties.

The structure of individual differences in Heterogeneous Stock mice across problem types and motivational systems

“…It should be added that the components identified in this study, as well as in our prior work, do not appear to be dependent to any significant degree upon activity or stress, at least given how these constructs were operationalized in this study (see Locurto & Scanlon 1998;Galsworthy et al 2002, for a similar finding). While more precise delineation of the structure of mouse problem-solving awaits further work, it appears that this work is not hindered by these potential artifacts.…”

“…These average correlations and levels of variance accounted for, not including the control components, are appreciably more powerful than the batteries reported by either Anderson (1993), Galsworthy et al (2002), or our earlier battery composed of water escape tasks (Locurto & Scanlon 1998). The variance explained by the first principal component in the three-task Anderson battery, which included no control procedures, averaged approximately 29%, and the average correlation was 0.33 (n 22).…”

“…In this study, as in Locurto & Scanlon (1998), Hebb-Williams and place learning marked a common component. This component has emerged despite the presence of a varying number and type of other tasks in these two batteries.…”

“…The water escape tasks were run as has been described in Locurto & Scanlon (1998). Briefly, water temperature was maintained at 26 AE 1 C. In each task subjects were started with their head facing the back wall of the arena/maze.…”

“…Other research programs that developed batteries of cognitive tasks have at times used predominantly latencies (e.g. Galsworthy et al 2002), a combination of errors and latencies (Anderson 1995) or have reported each measure separately (Locurto & Scanlon 1998). It is not possible based on prior evidence to decide whether one dependent measure or another serves as the best index of cognitive performance.…”