Behavioural Brain Research 177 (2007) 22–29
Spatial learning in Long-Evans Hooded rats and C57BL/6J mice:
Different strategies for different performance
, Morgane Besson
, Sandra Suarez
, Sylvie Granon
Laboratoire de Physiologie de la Perception et de l’Action, UMR CNRS 7124, Coll`ege de France, Paris, France
Unit´eR´ecepteurs & Cognition, D´epartement de Neuroscience, Institut Pasteur, CNRS 2182, 25 rue du Dr. Roux, 75015 Paris, France
Received 6 June 2006; received in revised form 6 November 2006; accepted 9 November 2006
Available online 8 December 2006
Spatial learning abilities of rodents have been extensively used to explore the management of a wide range of cognitive and emotional processes
such as learning, memory, attention and anxiety. Knowledge about the organization and processing of spatial learning has mainly been obtained
in rats. Due to increasing generation of genetically modiﬁed mice, cognitive abilities of mice are now extensively tested. The present paper aimed
at comparing spatial representation, learning and strategies in C57BL/6J mice and Long-Evans Hooded rats when subjected to the same spatial
learning paradigm, i.e. learning a food location in a crossmaze. We also analyzed the inﬂuence of environmental richness on learning modalities
in both species. Our results showed that rats and mice could exhibit similar spatial learning abilities in some circumstances. However, Long-Evans
rats and C57BL/6J mice may set up different strategies depending on the availability of visual information within the environment. Rats’ learning
strategies mainly relied on distant visual cues and seemed more efﬁcient than those used by mice as they needed less time than mice to solve the
task. We emphasize that the strategies of mice are less robust and ﬂexible than the ones set up by rats. Finally, the richness of the environment was
shown to affect speed and quality of spatial learning in both species.
© 2006 Published by Elsevier B.V.
Keywords: Behavior; Rat; Mice; Spatial learning; Exploration; Crossmaze; Food reward
Spatial tasks have long been studied in rodents because they
involve the management of a wide range of cognitive and emo-
tional processes such as learning, memory, attention and anxiety
that can be thus modelled in animals for which spatial orienta-
tion is naturally a signiﬁcant behavior. Moreover, spatial tests
involving the building up and the use of mental representa-
tion constitute useful methods to investigate structure–function
relationships, pharmacology, development and aging .
Knowledge about the organization and processing of spatial
learning has been mainly obtained in rats and afterwards has
been extended to other rodents, i.e. hamsters [23,26], gerbils
 and recently mice [7,17,22,32]. Indeed, for nearly two
decades now, genetically modiﬁed mice, either knock-out or
Corresponding author. Tel.: +33 1 40613777; fax: +33 1 45688836.
E-mail address: email@example.com (S. Granon).
knock-in strains, have been developed to assess the role of
particular genes , recently allowing access to their role within
a particular brain circuit . Cognitive abilities of those mice
are now extensively being tested ([4,8,17] for review), and mice
can help to study human psychiatric disorders (e.g. [2,19]).
However, strict comparison of spatial abilities between rats and
mice has rarely been performed [28,30,31]. In order to optimize
the use of mice as animal models of cognitive functions, we
investigated here whether mice and rats exhibited similar perfor-
mance when subjected to the same spatial learning paradigm.
Moreover, we asked whether their spatial strategies were
We compared performance of Long-Evans Hooded rats and
C57BL/6J mice submitted to the same paradigm, previously
designed to evaluate spatial learning ability and strategies [6,15].
We further explored the inﬂuence of environmental richness on
learning modalities in both species in order to manipulate infor-
mation processing. Long-Evans rats and C57BL/6 mice were
chosen among other strains of rodents because they are both the
0166-4328/$ – see front matter © 2006 Published by Elsevier B.V.