Imprinting, learning and development: from behaviour to brain and back.

Neural and behavioural analyses have shown that the formation of filial preferences in young, precocial birds involves at least two separate processes. One process is an emerging predisposition to approach stimuli with the characteristics of the natural mother. The other (learning) process of filial imprinting results in chicks preferentially-approaching a stimulus to which they have been exposed and involves forming links between the components of the exposed stimulus. The neural substrate for the predisposition is different from that underlying imprinting, and different regions of the chick brain are involved in distinct aspects of learning about imprinting stimuli.