Social isolation improves the performance of rodents in a novel cognitive flexibility task

Xin-Yuan Fei,Sha Liu,Liang Cheng,Yan-Hong Sun

doi:10.1186/s12983-019-0339-4

Abstract

BackgroundSocial isolation, i.e., the deprivation of social contact, is a highly stressful circumstance that affects behavioral and functional brain development in social animals. Cognitive flexibility, one of the essential executive brain function that facilitates survival problem solving, was reported to be impaired after social isolation rearing. However, most of the previous studies have focused on the constrained aspect of flexibility and little is known about the unconstrained aspect. In the present study, the unconstrained cognitive flexibility of Kunming mice (Mus musculus, Km) reared in isolation was examined by a novel digging task. The exploratory behavior of the mice was also tested utilizing the hole-board and elevated plus maze tests to explain the differences in cognitive flexibility between the mice reared socially and in isolation.ResultsThe results demonstrated that the isolated mice had a higher success rate in solving the novel digging problem and showed a higher rate of exploratory behavior compared with the controls. Linear regression analysis revealed that the time it took the mice to solve the digging problem was negatively associated with exploratory behavior.ConclusionsThe data suggest that social isolation rearing improves unconstrained cognitive flexibility in mice, which is probably related to an increase in their exploratory behavior. Such effects may reflect the behavioral and cognitive evolutionary adaptations of rodents to survive under complex and stressful conditions.

Highlights

Social isolation, i.e., the deprivation of social contact, is a highly stressful circumstance that affects behavioral and functional brain development in social animals
To determine whether the better performance of the isolated mice in the digging task was related to changes in exploratory behavior, the exploratory behavior of the mice under different rearing conditions was examined by the hole-board (HB) and elevated plus maze (EPM) tests, and correlations between performance in the digging task and exploratory behavior were examined
Displays of the isolated mice were significantly higher than that of the social mice, illustrating that social isolation increased the exploratory behavior of the mice

Summary

Introduction

I.e., the deprivation of social contact, is a highly stressful circumstance that affects behavioral and functional brain development in social animals. One of the essential executive brain function that facilitates survival problem solving, was reported to be impaired after social isolation rearing. Social isolation (i.e., the deprivation of social contact) during rodent adolescence is a highly stressful circumstance that affects behavior and structural and functional brain development [3–7]. An essential executive brain function that contributes to changing the behavior of an organism depending on situational demands, is very important for rodent survival in complex and constantly changing surroundings. Several studies have used rodent models to investigate the influence of social isolation on cognitive flexibility and reported behavioral impairments in reversal learning tasks after isolation rearing [21, 22]. Li and colleagues [22] reported that isolation rearing impaired the reversal

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Conclusion