Brown Institute for Brain Science

Resident-Intruder Aggression Assay

Rationale of Test

Often genetic manipulations or pharmacological interventions can increase aggression through a variety of mechanisms (altered sensory function, increased pain, direct effects on emotional brain centers). To test for alterations in general aggression, the resident intruder paradigm is a commonly used and robust assay.



For isolation-induced aggression, male mice are singly housed for ten days. Aggressive behaviors in mice are monitored during 5-min exposures to WT C57Bl6 male intruder mice that are been group-housed (five per cage) and matched with resident mice for approximate age and body weight. Five test sessions are conducted (one trial per day). The latency to first biting attack and the total number of biting attacks are recorded from digital recordings of each test session.


Relevant Controls

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