Citation

The posterior pallial amygdala (PoA) is located on the basolateral caudal telencephalon, including the
basal division of PoA (PoAb) and the compact division of PoA (PoAc). PoA plays a vital role in emotion
regulation and is considered a part of the amygdala in birds. However, the regulatory functions
responsible for motor behaviors and emotions between PoAb and PoAc are poorly understood. Therefore,
we studied the structure and function of PoA by tract-tracing methods, constant current electrical
stimulation, and different dopamine receptor drug injections in pigeons (Columba livia domestica). PoAb
connects reciprocally with two nuclear groups in the cerebrum: 1) a continuum comprising the temporo–
parieto–occipitalis, corticoidea dorsolateralis, hippocampus, and parahippocampalis areas and 2) rostral
areas of the hemisphere, including the nucleus septalis lateralis and nucleus taeniae amygdalae.
Extratelencephalic projections of PoAb terminate in the lateral hypothalamic nucleus and are scattered in
many limbic midbrain regions. PoAb and PoAc mainly mediated the turning movement. D1 agonist and
D2 antagonist could significantly reduce the latency period for entering into the central area and increase
the stay time in the central area, whereas D1 antagonist and D2 agonist had the opposite effect. These
findings indicate that PoAb may participate in interhemispheric exchange and that PoAc affects motor
behaviors by regulating emotions. Hence, PoAb and PoAc are important brain areas that mediate turning
behavior.