Neural correlates of species-typical behavior in the Syrian golden hamster.

Abstract

The behavior of Syrian golden hamsters with lesions to the medial frontal cortex (MF), orbital frontal cortex (OF), cingulate cortex (CING), posterior cortex (POST), hippocampus (HPC), septum (SEPT) or amygdala (AMYG) was compared with that of control hamsters in a variety of situations, including weight regulation, food hoarding, nest building, neophobia, bait shyness, sex preference, territorial aggression and shock-induced aggression. The behavior of hamsters with OF or AMYG lesions was doubly dissociable from the behavior of the hamsters with MF, HPC or SEPT lesions. The OF and AMYG lesions produced severe weight losses, and all OF hamsters were aphagic and adipsic, and subsequently died. The HPC, MF and SEPT lesions severely disrupted hoarding and nest building; the other lesions affected neither. None of the lesions impaired the development of bait shyness when a sucrose solution was paired with sickness, but AMYG and SEPT lesions may have produced a mild impairment when an NaCl solution was paired with sickness. Only amygdala lesions produced consistent behavioral changes on the social tests. Neither cingulate nor posterior cortical lesions significantly altered behavior on any of the tests. The results support the idea that different forebrain regions can be functionally dissociated by using behavorial tests that are biologically significant.