When animals explore an unfamiliar environment, they gather information that enables them to form a cognitive representation of that environment and to use it subsequently in traveling there. In the present study, rats were tested in a large arena as singles, then in dyads, and finally, again as singles, in order to examine the effect of the social environment on exploration. Traveling in dyads facilitated exploration compared to the behavior of the same rats when they explored alone. Specifically, each rat in a dyad traveled a greater distance with higher velocity and took wider turns compared to its lone traveling. Moreover, rats in dyads spent a long time together, shared a home base, and when traveling in the same direction, one rat was leading the other. In addition to exploring the same locations, leaders explored more “private” locations, not visited by the other rat. Features of the dyad behavior were carried over to the behavior of the same rats when tested as individuals, after the dyad trial. Compared to singles, dyads represent the first step toward grouping, and it is suggested that the conspicuous change between the behavior of a rat as single compared to its behavior when in a dyad should be greater than any further changes that may occur in spatial cognitive behavior of triads, quartets, or larger groups. In other words, while the present changes in spatial cognition observed in dyads represent a small step toward grouping, they are a giant leap for the individual.
Spatial representation Exploration Social environment Social cognition
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This study was supported by the Israel Science Foundation Grant 230/13 to DE. We are grateful to Naomi Paz for language editing, and to Shahaf Weiss and Pazit Zadicario for their support in experimentation and analysis. D.E. is a Visiting Professor at the Department of OTANES, University of South Africa.
This study and the maintenance conditions for the rats were carried out under the regulations and approval of the Institutional Committee for Animal Experimentation at Tel-Aviv University (permit # L-14-026).
Conflict of interest
The authors declare that they have no conflict of interest.
Spatial behavior in rat dyad. This videoclip illustrates how a rat dyad explores an unfamiliar environment, with attention primarily directed to the partner. In traveling rats take wide turns while following one another. Note that arena size is 6 × 5.6 m and therefore the rats move far from one another, but always turn to re-approach their partner (MPG 15386 kb)
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