Aggressive Behavior of Pigeons: Suppression by Archistriatal Lesions

The agonistic responses of pigeons to the introduction of a stick and the experimenter’s hand into their home cages is described. The effects of lesions of the archistriatum, a presumed homologue of the mammalian amygdala, of lesions of the overlying neostriatum and of control sham operations on this behavior in selected aggressive pigeons are reported. Only archistriatal lesions lead to a persistent depression of the aggressive and a converse increment of the avoidance components of the pigeon’s response to both test stimuli. The results are discussed in relation to other evidence on the role of the avian archistriatum and this structure’s correspondence with the amygdala.