Figure 6.

Insular cortex inhibition does not affect social novelty preference. A, Experimental overview. Rats were housed in groups to establish familiarity. After 2 weeks, experimental rats were habituated to the test arena and social interaction then given a 5 min novelty preference test with one of the experimental rat's cage mates (f, familiar) and an unfamiliar (u) rat. B, Mean (individual replicates) time spent in social interaction with the familiar and novel conspecifics. Experimental rats spent significantly more time investigating the unfamiliar target. **p = 0.005. C, To test the role of IC in social novelty preference, rats received pAAV5-hSyn-hM4D(Gi)-mCherry virus injections to IC and then housed in groups for at least 2 weeks. Social novelty preference tests were given 45 min after pretreatment with either vehicle or CNO (3 mg/kg, i.p.) on days 3 and 4. Experimental rats preferred interaction with the unfamiliar conspecific under both injection conditions (**main effect of familiarity, p = 0.005). D, Summary of mCherry expression indicating spread of hM4D(Gi) in the IC.