Modeling reciprocal social interactions, and communication, in mice

Background: Autism is defined in terms of three symptom groupings; deficiencies in reciprocal social interactions, deficiencies in communication, and the presence of restricted or ritualized behaviors. These three are not well correlated, nor do they necessarily respond similarly to treatment, suggesting that they may be under the control of different genetic and environmental mechanisms. Objectives: These factors indicate the desirability of selection and analysis of animal models that provide independent measures of the behaviors involved in these groupings. This abstract reflects a program of development of models of social interaction and communication. Methods: An ethological model of reciprocal social interaction involves C57BL/6J mice housed in stable groups in Visible Burrow Systems. Major measures include huddling during both active and inactive diurnal cycles, and approaches of mice, analyzed in terms of specific trajectory. An additional program on scent marking analyzes this major communication system in mice and protocol variations within the scent marking paradigm enable assessment of multiple aspects of commication in this species. Results: (VBS) Approaches from the rear elicit flight in the recipient suggesting that this is a nonamicable form of approach, whereas approaches from the front do not result in flight. Further, the response of the recipient to frontal approach provides further information about the reciprocity of the interaction. (Scent marking) Communication in mice can be precisely and selectively measured by scent marking, and the behavioral response to urinary scent marks. We provide data assessing social communication; responsivity to social signals; social recognition; social and nonsocial learning. Conclusions: These results suggest that behaviors directly relevant to the major symptom-groupings of autism can be characterized in mice. Mice showing variation in these behaviors are not autistic, but such behaviors can provide a highly relevant approach to analysis of genetic and experimental factors modulating these behaviors in autistic individuals.