Frontal forebrain lesions: effects on the foraging and apomorphine pecking of pigeons.

The role of the nucleus basalis prosencephali (Bas), a frontal forebrain structure peculiar to birds, in the control of forage pecking and apomorphine-induced pecking was investigated. In a quasi-natural grit-grain selection task bilateral coagulations of the Bas and the associated neostratum frontolaterale (Nfl) caused a marked fall in grain per peck uptake and a simultaneous increase in grit per peck uptake. Bas lesions also had a reducing effect on the compulsive pecking elicited by systemic injections of apomorphine. This confirms that the Bas is involved in the control of forage pecking and dopaminergic pecking of birds.